diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..57f1cb2
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1 @@
+/.idea/
\ No newline at end of file
diff --git a/config.go b/config.go
new file mode 100644
index 0000000..153460a
--- /dev/null
+++ b/config.go
@@ -0,0 +1,208 @@
+package otelchi
+
+import (
+ "net/http"
+
+ "github.com/go-chi/chi/v5"
+ otelmetric "go.opentelemetry.io/otel/metric"
+ "go.opentelemetry.io/otel/propagation"
+ oteltrace "go.opentelemetry.io/otel/trace"
+)
+
+// These defaults are used in `TraceHeaderConfig`.
+const (
+ DefaultTraceIDResponseHeaderKey = "X-Trace-Id"
+ DefaultTraceSampledResponseHeaderKey = "X-Trace-Sampled"
+)
+
+// config is used to configure the mux middleware.
+type config struct {
+ TracerProvider oteltrace.TracerProvider
+ MeterProvider otelmetric.MeterProvider
+ Propagators propagation.TextMapPropagator
+ ChiRoutes chi.Routes
+ RequestMethodInSpanName bool
+ Filters []Filter
+ TraceIDResponseHeaderKey string
+ TraceSampledResponseHeaderKey string
+ PublicEndpointFn func(r *http.Request) bool
+
+ DisableMeasureInflight bool
+ DisableMeasureSize bool
+}
+
+// Option specifies instrumentation configuration options.
+type Option interface {
+ apply(*config)
+}
+
+type optionFunc func(*config)
+
+func (o optionFunc) apply(c *config) {
+ o(c)
+}
+
+// Filter is a predicate used to determine whether a given http.Request should
+// be traced. A Filter must return true if the request should be traced.
+type Filter func(*http.Request) bool
+
+// WithPropagators specifies propagators to use for extracting
+// information from the HTTP requests. If none are specified, global
+// ones will be used.
+func WithPropagators(propagators propagation.TextMapPropagator) Option {
+ return optionFunc(func(cfg *config) {
+ cfg.Propagators = propagators
+ })
+}
+
+// WithTracerProvider specifies a tracer provider to use for creating a tracer.
+// If none is specified, the global provider is used.
+func WithTracerProvider(provider oteltrace.TracerProvider) Option {
+ return optionFunc(func(cfg *config) {
+ cfg.TracerProvider = provider
+ })
+}
+
+// WithMeterProvider specifies a meter provider to use for creating a meter.
+// If none is specified, the global provider is used.
+func WithMeterProvider(provider otelmetric.MeterProvider) Option {
+ return optionFunc(func(cfg *config) {
+ cfg.MeterProvider = provider
+ })
+}
+
+// WithMeasureInflightDisabled specifies whether to measure the number of inflight requests.
+// If this option is not set, the number of inflight requests will be measured.
+func WithMeasureInflightDisabled(isDisabled bool) Option {
+ return optionFunc(func(cfg *config) {
+ cfg.DisableMeasureInflight = isDisabled
+ })
+}
+
+// WithMeasureSizeDisabled specifies whether to measure the size of the response body.
+// If this option is not set, the size of the response body will be measured.
+func WithMeasureSizeDisabled(isDisabled bool) Option {
+ return optionFunc(func(cfg *config) {
+ cfg.DisableMeasureSize = isDisabled
+ })
+}
+
+// WithChiRoutes specified the routes that being used by application. Its main
+// purpose is to provide route pattern as span name during span creation. If this
+// option is not set, by default the span will be given name at the end of span
+// execution. For some people, this behavior is not desirable since they want
+// to override the span name on underlying handler. By setting this option, it
+// is possible for them to override the span name.
+func WithChiRoutes(routes chi.Routes) Option {
+ return optionFunc(func(cfg *config) {
+ cfg.ChiRoutes = routes
+ })
+}
+
+// WithRequestMethodInSpanName is used for adding http request method to span name.
+// While this is not necessary for vendors that properly implemented the tracing
+// specs (e.g Jaeger, AWS X-Ray, etc...), but for other vendors such as Elastic
+// and New Relic this might be helpful.
+//
+// See following threads for details:
+//
+// - https://github.com/riandyrn/otelchi/pull/3#issuecomment-1005883910
+// - https://github.com/riandyrn/otelchi/issues/6#issuecomment-1034461912
+func WithRequestMethodInSpanName(isActive bool) Option {
+ return optionFunc(func(cfg *config) {
+ cfg.RequestMethodInSpanName = isActive
+ })
+}
+
+// WithFilter adds a filter to the list of filters used by the handler.
+// If any filter indicates to exclude a request then the request will not be
+// traced. All filters must allow a request to be traced for a Span to be created.
+// If no filters are provided then all requests are traced.
+// Filters will be invoked for each processed request, it is advised to make them
+// simple and fast.
+func WithFilter(filter Filter) Option {
+ return optionFunc(func(cfg *config) {
+ cfg.Filters = append(cfg.Filters, filter)
+ })
+}
+
+// WithTraceIDResponseHeader enables adding trace id into response header.
+// It accepts a function that generates the header key name. If this parameter
+// function set to `nil` the default header key which is `X-Trace-Id` will be used.
+//
+// Deprecated: use `WithTraceResponseHeaders` instead.
+func WithTraceIDResponseHeader(headerKeyFunc func() string) Option {
+ cfg := TraceHeaderConfig{
+ TraceIDHeader: "",
+ TraceSampledHeader: "",
+ }
+ if headerKeyFunc != nil {
+ cfg.TraceIDHeader = headerKeyFunc()
+ }
+ return WithTraceResponseHeaders(cfg)
+}
+
+// TraceHeaderConfig is configuration for trace headers in the response.
+type TraceHeaderConfig struct {
+ TraceIDHeader string // if non-empty overrides the default of X-Trace-ID
+ TraceSampledHeader string // if non-empty overrides the default of X-Trace-Sampled
+}
+
+// WithTraceResponseHeaders configures the response headers for trace information.
+// It accepts a TraceHeaderConfig struct that contains the keys for the Trace ID
+// and Trace Sampled headers. If the provided keys are empty, default values will
+// be used for the respective headers.
+func WithTraceResponseHeaders(cfg TraceHeaderConfig) Option {
+ return optionFunc(func(c *config) {
+ c.TraceIDResponseHeaderKey = cfg.TraceIDHeader
+ if c.TraceIDResponseHeaderKey == "" {
+ c.TraceIDResponseHeaderKey = DefaultTraceIDResponseHeaderKey
+ }
+
+ c.TraceSampledResponseHeaderKey = cfg.TraceSampledHeader
+ if c.TraceSampledResponseHeaderKey == "" {
+ c.TraceSampledResponseHeaderKey = DefaultTraceSampledResponseHeaderKey
+ }
+ })
+}
+
+// WithPublicEndpoint is used for marking every endpoint as public endpoint.
+// This means if the incoming request has span context, it won't be used as
+// parent span by the span generated by this middleware, instead the generated
+// span will be the root span (new trace) and then linked to the span from the
+// incoming request.
+//
+// Let say we have the following scenario:
+//
+// 1. We have 2 systems: `SysA` & `SysB`.
+// 2. `SysA` has the following services: `SvcA.1` & `SvcA.2`.
+// 3. `SysB` has the following services: `SvcB.1` & `SvcB.2`.
+// 4. `SvcA.2` is used internally only by `SvcA.1`.
+// 5. `SvcB.2` is used internally only by `SvcB.1`.
+// 6. All of these services already instrumented otelchi & using the same collector (e.g Jaeger).
+// 7. In `SvcA.1` we should set `WithPublicEndpoint()` since it is the entry point (a.k.a "public endpoint") for entering `SysA`.
+// 8. In `SvcA.2` we should not set `WithPublicEndpoint()` since it is only used internally by `SvcA.1` inside `SysA`.
+// 9. Point 7 & 8 also applies to both services in `SysB`.
+//
+// Now, whenever `SvcA.1` calls `SvcA.2` there will be only a single trace generated. This trace will contain 2 spans: root span from `SvcA.1` & child span from `SvcA.2`.
+//
+// But if let say `SvcA.2` calls `SvcB.1`, then there will be 2 traces generated: trace from `SysA` & trace from `SysB`. But in trace generated in `SysB` there will be like a marking that this trace is actually related to trace in `SysA` (a.k.a linked with the trace from `SysA`).
+func WithPublicEndpoint() Option {
+ return WithPublicEndpointFn(func(r *http.Request) bool { return true })
+}
+
+// WithPublicEndpointFn runs with every request, and allows conditionally
+// configuring the Handler to link the generated span with an incoming span
+// context.
+//
+// If the function return `true` the generated span will be linked with the
+// incoming span context. Otherwise, the generated span will be set as the
+// child span of the incoming span context.
+//
+// Essentially it has the same functionality as `WithPublicEndpoint` but with
+// more flexibility.
+func WithPublicEndpointFn(fn func(r *http.Request) bool) Option {
+ return optionFunc(func(cfg *config) {
+ cfg.PublicEndpointFn = fn
+ })
+}
diff --git a/examples/basic/Dockerfile b/examples/basic/Dockerfile
new file mode 100644
index 0000000..8abd79a
--- /dev/null
+++ b/examples/basic/Dockerfile
@@ -0,0 +1,7 @@
+FROM golang:1.22-alpine3.20
+
+WORKDIR /go/src/toastielab.dev/toastie-stuff/otelchi/examples/basic
+RUN go mod download -x
+RUN go build -o server
+
+ENTRYPOINT ["./server"]
\ No newline at end of file
diff --git a/examples/basic/Makefile b/examples/basic/Makefile
new file mode 100644
index 0000000..9d8b697
--- /dev/null
+++ b/examples/basic/Makefile
@@ -0,0 +1,6 @@
+run:
+ -make down
+ docker-compose up --build
+
+down:
+ docker-compose down --remove-orphans
\ No newline at end of file
diff --git a/examples/basic/README.md b/examples/basic/README.md
new file mode 100644
index 0000000..2a1d0a1
--- /dev/null
+++ b/examples/basic/README.md
@@ -0,0 +1,25 @@
+# go-chi/chi instrumentation example
+
+An HTTP server using go-chi/chi and instrumentation. The server has a `/users/{id:[0-9]+}` endpoint. The server generates span information to `stdout`.
+
+These instructions expect you to have [docker-compose](https://docs.docker.com/compose/) installed.
+
+Bring up the `mux-server` and `mux-client` services to run the
+example:
+
+```sh
+docker-compose up --detach mux-server mux-client
+```
+
+The `mux-client` service sends just one HTTP request to the `mux-server`
+and then exits. View the span generated by the `mux-server` in the logs:
+
+```sh
+docker-compose logs mux-server
+```
+
+Shut down the services when you are finished with the example:
+
+```sh
+docker-compose down
+```
\ No newline at end of file
diff --git a/examples/basic/docker-compose.yml b/examples/basic/docker-compose.yml
new file mode 100644
index 0000000..ef28b96
--- /dev/null
+++ b/examples/basic/docker-compose.yml
@@ -0,0 +1,18 @@
+version: "2.4"
+services:
+ mux-client:
+ image: curlimages/curl:7.84.0
+ command: "curl -XGET http://mux-server:8080/users/123"
+ depends_on:
+ - mux-server
+ mux-server:
+ build:
+ # we set the build context to toastielab.dev/toastie-stuff/otelchi because we use relative
+ # path in go.mod for otelchi library
+ context: ../../
+
+ # since we are on toastielab.dev/toastie-stuff/otelchi, the dockerfile location would be
+ # in ./examples/basic/Dockerfile
+ dockerfile: ./examples/basic/Dockerfile
+ ports:
+ - "8080:8080"
\ No newline at end of file
diff --git a/examples/basic/go.mod b/examples/basic/go.mod
new file mode 100644
index 0000000..3f86248
--- /dev/null
+++ b/examples/basic/go.mod
@@ -0,0 +1,25 @@
+module toastielab.dev/toastie-stuff/otelchi/examples/basic
+
+go 1.22.0
+
+replace toastielab.dev/toastie-stuff/otelchi => ../../
+
+require (
+ github.com/go-chi/chi/v5 v5.1.0
+ toastielab.dev/toastie-stuff/otelchi v0.10.0
+ go.opentelemetry.io/otel v1.30.0
+ go.opentelemetry.io/otel/exporters/stdout/stdoutmetric v1.30.0
+ go.opentelemetry.io/otel/exporters/stdout/stdouttrace v1.30.0
+ go.opentelemetry.io/otel/sdk v1.30.0
+ go.opentelemetry.io/otel/sdk/metric v1.30.0
+ go.opentelemetry.io/otel/trace v1.30.0
+)
+
+require (
+ github.com/felixge/httpsnoop v1.0.4 // indirect
+ github.com/go-logr/logr v1.4.2 // indirect
+ github.com/go-logr/stdr v1.2.2 // indirect
+ github.com/google/uuid v1.6.0 // indirect
+ go.opentelemetry.io/otel/metric v1.30.0 // indirect
+ golang.org/x/sys v0.25.0 // indirect
+)
\ No newline at end of file
diff --git a/examples/basic/go.sum b/examples/basic/go.sum
new file mode 100644
index 0000000..48d55b1
--- /dev/null
+++ b/examples/basic/go.sum
@@ -0,0 +1,15 @@
+github.com/felixge/httpsnoop v1.0.4/go.mod h1:m8KPJKqk1gH5J9DgRY2ASl2lWCfGKXixSwevea8zH2U=
+github.com/go-chi/chi/v5 v5.1.0/go.mod h1:DslCQbL2OYiznFReuXYUmQ2hGd1aDpCnlMNITLSKoi8=
+github.com/go-logr/logr v1.2.2/go.mod h1:jdQByPbusPIv2/zmleS9BjJVeZ6kBagPoEUsqbVz/1A=
+github.com/go-logr/logr v1.4.2/go.mod h1:9T104GzyrTigFIr8wt5mBrctHMim0Nb2HLGrmQ40KvY=
+github.com/go-logr/stdr v1.2.2/go.mod h1:mMo/vtBO5dYbehREoey6XUKy/eSumjCCveDpRre4VKE=
+github.com/google/uuid v1.6.0/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
+github.com/riandyrn/otelchi v0.10.0/go.mod h1:zBaX2FavWMlsvq4GqHit+QXxF1c5wIMZZFaYyW4+7FA=
+go.opentelemetry.io/otel v1.30.0/go.mod h1:tFw4Br9b7fOS+uEao81PJjVMjW/5fvNCbpsDIXqP0pc=
+go.opentelemetry.io/otel/exporters/stdout/stdoutmetric v1.30.0/go.mod h1:bxiX8eUeKoAEQmbq/ecUT8UqZwCjZW52yJrXJUSozsk=
+go.opentelemetry.io/otel/exporters/stdout/stdouttrace v1.30.0/go.mod h1:ljkUDtAMdleoi9tIG1R6dJUpVwDcYjw3J2Q6Q/SuiC0=
+go.opentelemetry.io/otel/metric v1.30.0/go.mod h1:aXTfST94tswhWEb+5QjlSqG+cZlmyXy/u8jFpor3WqQ=
+go.opentelemetry.io/otel/sdk v1.30.0/go.mod h1:p14X4Ok8S+sygzblytT1nqG98QG2KYKv++HE0LY/mhg=
+go.opentelemetry.io/otel/sdk/metric v1.30.0/go.mod h1:waS6P3YqFNzeP01kuo/MBBYqaoBJl7efRQHOaydhy1Y=
+go.opentelemetry.io/otel/trace v1.30.0/go.mod h1:5EyKqTzzmyqB9bwtCCq6pDLktPK6fmGf/Dph+8VI02o=
+golang.org/x/sys v0.25.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
diff --git a/examples/basic/main.go b/examples/basic/main.go
new file mode 100644
index 0000000..1121bb5
--- /dev/null
+++ b/examples/basic/main.go
@@ -0,0 +1,99 @@
+package main
+
+import (
+ "context"
+ "fmt"
+ "log"
+ "net/http"
+ "time"
+
+ "github.com/go-chi/chi/v5"
+ "go.opentelemetry.io/otel"
+ "go.opentelemetry.io/otel/attribute"
+ "go.opentelemetry.io/otel/exporters/stdout/stdoutmetric"
+ "go.opentelemetry.io/otel/exporters/stdout/stdouttrace"
+ "go.opentelemetry.io/otel/propagation"
+ sdkmetric "go.opentelemetry.io/otel/sdk/metric"
+ "go.opentelemetry.io/otel/sdk/resource"
+ sdktrace "go.opentelemetry.io/otel/sdk/trace"
+ semconv "go.opentelemetry.io/otel/semconv/v1.20.0"
+ oteltrace "go.opentelemetry.io/otel/trace"
+
+ "toastielab.dev/toastie-stuff/otelchi"
+)
+
+var tracer oteltrace.Tracer
+
+func main() {
+ // initialize trace provider
+ tp, mp := initOtelProviders()
+ defer func() {
+ if err := tp.Shutdown(context.Background()); err != nil {
+ log.Printf("Error shutting down tracer provider: %v", err)
+ }
+ if err := mp.Shutdown(context.Background()); err != nil {
+ log.Printf("Error shutting down meter provider: %v", err)
+ }
+ }()
+ // set global tracer provider & text propagators
+ otel.SetTracerProvider(tp)
+ otel.SetMeterProvider(mp)
+ otel.SetTextMapPropagator(propagation.NewCompositeTextMapPropagator(propagation.TraceContext{}, propagation.Baggage{}))
+ // initialize tracer
+ tracer = otel.Tracer("mux-server")
+
+ // define router
+ r := chi.NewRouter()
+ r.Use(otelchi.Middleware("my-server", otelchi.WithChiRoutes(r)))
+ r.HandleFunc("/users/{id:[0-9]+}", func(w http.ResponseWriter, r *http.Request) {
+ id := chi.URLParam(r, "id")
+ name := getUser(r.Context(), id)
+ reply := fmt.Sprintf("user %s (id %s)\n", name, id)
+ w.Write(([]byte)(reply))
+ })
+
+ // serve router
+ _ = http.ListenAndServe(":8080", r)
+}
+
+func initOtelProviders() (*sdktrace.TracerProvider, *sdkmetric.MeterProvider) {
+ traceExporter, err := stdouttrace.New(stdouttrace.WithPrettyPrint())
+ if err != nil {
+ log.Fatal(err)
+ }
+
+ metricExporter, err := stdoutmetric.New(stdoutmetric.WithPrettyPrint())
+ if err != nil {
+ log.Fatal(err)
+ }
+
+ res, err := resource.New(
+ context.Background(),
+ resource.WithAttributes(
+ // the service name used to display traces in backends
+ semconv.ServiceNameKey.String("mux-server"),
+ ),
+ )
+ if err != nil {
+ log.Fatalf("unable to initialize resource due: %v", err)
+ }
+ return sdktrace.NewTracerProvider(
+ sdktrace.WithSampler(sdktrace.AlwaysSample()),
+ sdktrace.WithBatcher(traceExporter),
+ sdktrace.WithResource(res),
+ ), sdkmetric.NewMeterProvider(
+ sdkmetric.WithReader(sdkmetric.NewPeriodicReader(metricExporter,
+ sdkmetric.WithInterval(time.Second*30),
+ )),
+ sdkmetric.WithResource(res),
+ )
+}
+
+func getUser(ctx context.Context, id string) string {
+ _, span := tracer.Start(ctx, "getUser", oteltrace.WithAttributes(attribute.String("id", id)))
+ defer span.End()
+ if id == "123" {
+ return "otelchi tester"
+ }
+ return "unknown"
+}
diff --git a/examples/multi-services/Makefile b/examples/multi-services/Makefile
new file mode 100644
index 0000000..9d8b697
--- /dev/null
+++ b/examples/multi-services/Makefile
@@ -0,0 +1,6 @@
+run:
+ -make down
+ docker-compose up --build
+
+down:
+ docker-compose down --remove-orphans
\ No newline at end of file
diff --git a/examples/multi-services/README.md b/examples/multi-services/README.md
new file mode 100644
index 0000000..777be67
--- /dev/null
+++ b/examples/multi-services/README.md
@@ -0,0 +1,33 @@
+# Multi Services Example
+
+This is a simple example of how instrumenting multiple services.
+
+There are 2 services in this example:
+
+- `front-svc` => the front service receiving requests from the client
+- `back-svc` => the service that is being called by `front-svc` (hence named `back`)
+
+
+
+All traces will be collected in [Jaeger](https://www.jaegertracing.io/).
+
+## How to Run
+
+Make sure to have Docker & Docker Compose installed in your system. After that run this command:
+
+```
+> make run
+```
+
+If the command runs successfully (it will take a moment), you will see something like this in the terminal:
+
+```
+back-svc_1 | 2022/07/23 01:49:29 back service is listening on :8091
+front-svc_1 | 2022/07/23 01:49:26 front service is listening on :8090
+...
+multi-services_client_1 exited with code 0
+```
+
+Open your browser and access `http://localhost:16686` to access the Jaeger UI.
+
+You should see some traces available already in the UI.
\ No newline at end of file
diff --git a/examples/multi-services/architecture.svg b/examples/multi-services/architecture.svg
new file mode 100644
index 0000000..b661da1
--- /dev/null
+++ b/examples/multi-services/architecture.svg
@@ -0,0 +1,4 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!-- Do not edit this file with editors other than diagrams.net -->
+<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
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\ No newline at end of file
diff --git a/examples/multi-services/back-svc/Dockerfile b/examples/multi-services/back-svc/Dockerfile
new file mode 100644
index 0000000..448341f
--- /dev/null
+++ b/examples/multi-services/back-svc/Dockerfile
@@ -0,0 +1,13 @@
+FROM golang:1.22-alpine3.20
+WORKDIR /go/src/toastielab.dev/toastie-stuff/otelchi
+
+RUN apk --no-cache add curl
+COPY . .
+
+WORKDIR /go/src/toastielab.dev/toastie-stuff/otelchi/examples/multi-services
+RUN go mod download -x
+
+WORKDIR /go/src/toastielab.dev/toastie-stuff/otelchi/examples/multi-services/back-svc
+RUN go build -o server
+
+ENTRYPOINT ["./server"]
\ No newline at end of file
diff --git a/examples/multi-services/back-svc/main.go b/examples/multi-services/back-svc/main.go
new file mode 100644
index 0000000..5fd9de3
--- /dev/null
+++ b/examples/multi-services/back-svc/main.go
@@ -0,0 +1,54 @@
+package main
+
+import (
+ "context"
+ "fmt"
+ "log"
+ "math/rand"
+ "net/http"
+ "time"
+
+ "github.com/go-chi/chi/v5"
+ "go.opentelemetry.io/otel/trace"
+
+ "toastielab.dev/toastie-stuff/otelchi"
+ "toastielab.dev/toastie-stuff/otelchi/examples/multi-services/utils"
+)
+
+const (
+ addr = ":8091"
+ serviceName = "back-svc"
+)
+
+func main() {
+ // init tracer provider
+ tracer, err := utils.NewTracer(serviceName)
+ if err != nil {
+ log.Fatalf("unable to initialize tracer provider due: %v", err)
+ }
+
+ if err = utils.NewMeter(serviceName); err != nil {
+ log.Fatalf("unable to initialize meter provider due: %v", err)
+ }
+
+ // define router
+ r := chi.NewRouter()
+ r.Use(otelchi.Middleware(serviceName, otelchi.WithChiRoutes(r)))
+ r.Get("/", utils.HealthCheckHandler)
+ r.Get("/name", func(w http.ResponseWriter, r *http.Request) {
+ w.Write([]byte(generateName(r.Context(), tracer)))
+ })
+ log.Printf("back service is listening on %v", addr)
+ err = http.ListenAndServe(addr, r)
+ if err != nil {
+ log.Fatalf("unable to execute server due: %v", err)
+ }
+}
+
+func generateName(ctx context.Context, tracer trace.Tracer) string {
+ _, span := tracer.Start(ctx, "generateName")
+ defer span.End()
+
+ rndNum := rand.New(rand.NewSource(time.Now().UnixNano())).Intn(100000)
+ return fmt.Sprintf("user_%v", rndNum)
+}
diff --git a/examples/multi-services/front-svc/Dockerfile b/examples/multi-services/front-svc/Dockerfile
new file mode 100644
index 0000000..95cc048
--- /dev/null
+++ b/examples/multi-services/front-svc/Dockerfile
@@ -0,0 +1,13 @@
+FROM golang:1.22-alpine3.20
+WORKDIR /go/src/toastielab.dev/toastie-stuff/otelchi
+
+RUN apk --no-cache add curl
+COPY . .
+
+WORKDIR /go/src/toastielab.dev/toastie-stuff/otelchi/examples/multi-services
+RUN go mod download -x
+
+WORKDIR /go/src/toastielab.dev/toastie-stuff/otelchi/examples/multi-services/front-svc
+RUN go build -o server
+
+ENTRYPOINT ["./server"]
\ No newline at end of file
diff --git a/examples/multi-services/front-svc/main.go b/examples/multi-services/front-svc/main.go
new file mode 100644
index 0000000..da818af
--- /dev/null
+++ b/examples/multi-services/front-svc/main.go
@@ -0,0 +1,84 @@
+package main
+
+import (
+ "context"
+ "fmt"
+ "io"
+ "log"
+ "net/http"
+ "os"
+
+ "github.com/go-chi/chi/v5"
+ "go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp"
+ "go.opentelemetry.io/otel/codes"
+ "go.opentelemetry.io/otel/trace"
+
+ "toastielab.dev/toastie-stuff/otelchi"
+ "toastielab.dev/toastie-stuff/otelchi/examples/multi-services/utils"
+)
+
+const (
+ envKeyBackServiceURL = "BACK_SERVICE_URL"
+ addr = ":8090"
+ serviceName = "front-svc"
+)
+
+func main() {
+ // initialize tracer
+ tracer, err := utils.NewTracer(serviceName)
+ if err != nil {
+ log.Fatalf("unable to initialize tracer due: %v", err)
+ }
+
+ if err = utils.NewMeter(serviceName); err != nil {
+ log.Fatalf("unable to initialize meter provider due: %v", err)
+ }
+
+ // define router
+ r := chi.NewRouter()
+ r.Use(otelchi.Middleware(serviceName, otelchi.WithChiRoutes(r)))
+ r.Get("/", utils.HealthCheckHandler)
+ r.Get("/greet", func(w http.ResponseWriter, r *http.Request) {
+ name, err := getRandomName(r.Context(), tracer)
+ if err != nil {
+ w.WriteHeader(http.StatusInternalServerError)
+ w.Write([]byte(err.Error()))
+ return
+ }
+ w.Write([]byte(fmt.Sprintf("Hello, %s!", name)))
+ })
+ // execute server
+ log.Printf("front service is listening on %v", addr)
+ err = http.ListenAndServe(addr, r)
+ if err != nil {
+ log.Fatalf("unable to execute server due: %v", err)
+ }
+}
+
+func getRandomName(ctx context.Context, tracer trace.Tracer) (string, error) {
+ // start span
+ ctx, span := tracer.Start(ctx, "getRandomName")
+ defer span.End()
+
+ // call back service, notice that here we call the service using instrumented
+ // http client
+ resp, err := otelhttp.Get(ctx, os.Getenv(envKeyBackServiceURL)+"/name")
+ if err != nil {
+ err = fmt.Errorf("unable to execute http request due: %w", err)
+ span.RecordError(err)
+ span.SetStatus(codes.Error, err.Error())
+ return "", err
+ }
+ defer resp.Body.Close()
+
+ // read response body
+ data, err := io.ReadAll(resp.Body)
+ if err != nil {
+ err = fmt.Errorf("unable to read response data due: %w", err)
+ span.RecordError(err)
+ span.SetStatus(codes.Error, err.Error())
+ return "", err
+ }
+
+ return string(data), nil
+}
diff --git a/examples/multi-services/go.mod b/examples/multi-services/go.mod
new file mode 100644
index 0000000..fa7fc77
--- /dev/null
+++ b/examples/multi-services/go.mod
@@ -0,0 +1,36 @@
+module toastielab.dev/toastie-stuff/otelchi/examples/multi-services
+
+go 1.22.0
+
+replace toastielab.dev/toastie-stuff/otelchi => ../../
+
+require (
+ github.com/go-chi/chi/v5 v5.1.0
+ toastielab.dev/toastie-stuff/otelchi v0.10.0
+ go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp v0.53.0
+ go.opentelemetry.io/otel v1.30.0
+ go.opentelemetry.io/otel/exporters/otlp/otlpmetric/otlpmetrichttp v1.30.0
+ go.opentelemetry.io/otel/exporters/otlp/otlptrace v1.30.0
+ go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracehttp v1.30.0
+ go.opentelemetry.io/otel/sdk v1.30.0
+ go.opentelemetry.io/otel/sdk/metric v1.30.0
+ go.opentelemetry.io/otel/trace v1.30.0
+)
+
+require (
+ github.com/cenkalti/backoff/v4 v4.3.0 // indirect
+ github.com/felixge/httpsnoop v1.0.4 // indirect
+ github.com/go-logr/logr v1.4.2 // indirect
+ github.com/go-logr/stdr v1.2.2 // indirect
+ github.com/google/uuid v1.6.0 // indirect
+ github.com/grpc-ecosystem/grpc-gateway/v2 v2.22.0 // indirect
+ go.opentelemetry.io/otel/metric v1.30.0 // indirect
+ go.opentelemetry.io/proto/otlp v1.3.1 // indirect
+ golang.org/x/net v0.29.0 // indirect
+ golang.org/x/sys v0.25.0 // indirect
+ golang.org/x/text v0.18.0 // indirect
+ google.golang.org/genproto/googleapis/api v0.0.0-20240903143218-8af14fe29dc1 // indirect
+ google.golang.org/genproto/googleapis/rpc v0.0.0-20240903143218-8af14fe29dc1 // indirect
+ google.golang.org/grpc v1.66.1 // indirect
+ google.golang.org/protobuf v1.34.2 // indirect
+)
\ No newline at end of file
diff --git a/examples/multi-services/go.sum b/examples/multi-services/go.sum
new file mode 100644
index 0000000..576a522
--- /dev/null
+++ b/examples/multi-services/go.sum
@@ -0,0 +1,25 @@
+github.com/cenkalti/backoff/v4 v4.3.0/go.mod h1:Y3VNntkOUPxTVeUxJ/G5vcM//AlwfmyYozVcomhLiZE=
+github.com/felixge/httpsnoop v1.0.4/go.mod h1:m8KPJKqk1gH5J9DgRY2ASl2lWCfGKXixSwevea8zH2U=
+github.com/go-chi/chi/v5 v5.1.0/go.mod h1:DslCQbL2OYiznFReuXYUmQ2hGd1aDpCnlMNITLSKoi8=
+github.com/go-logr/logr v1.2.2/go.mod h1:jdQByPbusPIv2/zmleS9BjJVeZ6kBagPoEUsqbVz/1A=
+github.com/go-logr/logr v1.4.2/go.mod h1:9T104GzyrTigFIr8wt5mBrctHMim0Nb2HLGrmQ40KvY=
+github.com/go-logr/stdr v1.2.2/go.mod h1:mMo/vtBO5dYbehREoey6XUKy/eSumjCCveDpRre4VKE=
+github.com/google/uuid v1.6.0/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
+github.com/grpc-ecosystem/grpc-gateway/v2 v2.22.0/go.mod h1:ggCgvZ2r7uOoQjOyu2Y1NhHmEPPzzuhWgcza5M1Ji1I=
+go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp v0.53.0/go.mod h1:jjdQuTGVsXV4vSs+CJ2qYDeDPf9yIJV23qlIzBm73Vg=
+go.opentelemetry.io/otel v1.30.0/go.mod h1:tFw4Br9b7fOS+uEao81PJjVMjW/5fvNCbpsDIXqP0pc=
+go.opentelemetry.io/otel/exporters/otlp/otlpmetric/otlpmetrichttp v1.30.0/go.mod h1:qqN/uFdpeitTvm+JDqqnjm517pmQRYxTORbETHq5tOc=
+go.opentelemetry.io/otel/exporters/otlp/otlptrace v1.30.0/go.mod h1:KQsVNh4OjgjTG0G6EiNi1jVpnaeeKsKMRwbLN+f1+8M=
+go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracehttp v1.30.0/go.mod h1:4lVs6obhSVRb1EW5FhOuBTyiQhtRtAnnva9vD3yRfq8=
+go.opentelemetry.io/otel/metric v1.30.0/go.mod h1:aXTfST94tswhWEb+5QjlSqG+cZlmyXy/u8jFpor3WqQ=
+go.opentelemetry.io/otel/sdk v1.30.0/go.mod h1:p14X4Ok8S+sygzblytT1nqG98QG2KYKv++HE0LY/mhg=
+go.opentelemetry.io/otel/sdk/metric v1.30.0/go.mod h1:waS6P3YqFNzeP01kuo/MBBYqaoBJl7efRQHOaydhy1Y=
+go.opentelemetry.io/otel/trace v1.30.0/go.mod h1:5EyKqTzzmyqB9bwtCCq6pDLktPK6fmGf/Dph+8VI02o=
+go.opentelemetry.io/proto/otlp v1.3.1/go.mod h1:0X1WI4de4ZsLrrJNLAQbFeLCm3T7yBkR0XqQ7niQU+8=
+golang.org/x/net v0.29.0/go.mod h1:gLkgy8jTGERgjzMic6DS9+SP0ajcu6Xu3Orq/SpETg0=
+golang.org/x/sys v0.25.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
+golang.org/x/text v0.18.0/go.mod h1:BuEKDfySbSR4drPmRPG/7iBdf8hvFMuRexcpahXilzY=
+google.golang.org/genproto/googleapis/api v0.0.0-20240903143218-8af14fe29dc1/go.mod h1:qpvKtACPCQhAdu3PyQgV4l3LMXZEtft7y8QcarRsp9I=
+google.golang.org/genproto/googleapis/rpc v0.0.0-20240903143218-8af14fe29dc1/go.mod h1:UqMtugtsSgubUsoxbuAoiCXvqvErP7Gf0so0mK9tHxU=
+google.golang.org/grpc v1.66.1/go.mod h1:s3/l6xSSCURdVfAnL+TqCNMyTDAGN6+lZeVxnZR128Y=
+google.golang.org/protobuf v1.34.2/go.mod h1:qYOHts0dSfpeUzUFpOMr/WGzszTmLH+DiWniOlNbLDw=
diff --git a/examples/multi-services/utils/healthcheck.go b/examples/multi-services/utils/healthcheck.go
new file mode 100644
index 0000000..2e78606
--- /dev/null
+++ b/examples/multi-services/utils/healthcheck.go
@@ -0,0 +1,7 @@
+package utils
+
+import "net/http"
+
+func HealthCheckHandler(w http.ResponseWriter, r *http.Request) {
+ w.Write([]byte("It's working!"))
+}
diff --git a/examples/multi-services/utils/meter.go b/examples/multi-services/utils/meter.go
new file mode 100644
index 0000000..bd80690
--- /dev/null
+++ b/examples/multi-services/utils/meter.go
@@ -0,0 +1,39 @@
+package utils
+
+import (
+ "context"
+ "fmt"
+ "time"
+
+ "go.opentelemetry.io/otel"
+ "go.opentelemetry.io/otel/exporters/otlp/otlpmetric/otlpmetrichttp"
+ sdkmetric "go.opentelemetry.io/otel/sdk/metric"
+ "go.opentelemetry.io/otel/sdk/resource"
+ semconv "go.opentelemetry.io/otel/semconv/v1.20.0"
+)
+
+func NewMeter(svcName string) error {
+ // create otlp exporter, notice that here we are using insecure option
+ // because we just want to export the trace locally, also notice that
+ // here we don't set any endpoint because by default the otel will load
+ // the endpoint from the environment variable `OTEL_EXPORTER_OTLP_ENDPOINT`
+ exporter, err := otlpmetrichttp.New(
+ context.Background(),
+ )
+ if err != nil {
+ return fmt.Errorf("unable to initialize exporter due: %w", err)
+ }
+ // initialize tracer provider
+ tp := sdkmetric.NewMeterProvider(
+ sdkmetric.WithReader(sdkmetric.NewPeriodicReader(exporter, sdkmetric.WithInterval(30*time.Second))),
+ sdkmetric.WithResource(resource.NewWithAttributes(
+ semconv.SchemaURL,
+ semconv.ServiceNameKey.String(svcName),
+ )),
+ )
+ // set tracer provider and propagator properly, this is to ensure all
+ // instrumentation library could run well
+ otel.SetMeterProvider(tp)
+
+ return nil
+}
diff --git a/examples/multi-services/utils/tracer.go b/examples/multi-services/utils/tracer.go
new file mode 100644
index 0000000..90b9a0c
--- /dev/null
+++ b/examples/multi-services/utils/tracer.go
@@ -0,0 +1,45 @@
+package utils
+
+import (
+ "context"
+ "fmt"
+
+ "go.opentelemetry.io/otel"
+ "go.opentelemetry.io/otel/exporters/otlp/otlptrace"
+ "go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracehttp"
+ "go.opentelemetry.io/otel/propagation"
+ "go.opentelemetry.io/otel/sdk/resource"
+ sdktrace "go.opentelemetry.io/otel/sdk/trace"
+ semconv "go.opentelemetry.io/otel/semconv/v1.20.0"
+ "go.opentelemetry.io/otel/trace"
+)
+
+func NewTracer(svcName string) (trace.Tracer, error) {
+ // create otlp exporter, notice that here we are using insecure option
+ // because we just want to export the trace locally, also notice that
+ // here we don't set any endpoint because by default the otel will load
+ // the endpoint from the environment variable `OTEL_EXPORTER_OTLP_ENDPOINT`
+ exporter, err := otlptrace.New(
+ context.Background(),
+ otlptracehttp.NewClient(otlptracehttp.WithInsecure()),
+ )
+ if err != nil {
+ return nil, fmt.Errorf("unable to initialize exporter due: %w", err)
+ }
+ // initialize tracer provider
+ tp := sdktrace.NewTracerProvider(
+ sdktrace.WithSampler(sdktrace.AlwaysSample()),
+ sdktrace.WithBatcher(exporter),
+ sdktrace.WithResource(resource.NewWithAttributes(
+ semconv.SchemaURL,
+ semconv.ServiceNameKey.String(svcName),
+ )),
+ )
+ // set tracer provider and propagator properly, this is to ensure all
+ // instrumentation library could run well
+ otel.SetTracerProvider(tp)
+ otel.SetTextMapPropagator(propagation.NewCompositeTextMapPropagator(propagation.TraceContext{}, propagation.Baggage{}))
+
+ // returns tracer
+ return otel.Tracer(svcName), nil
+}
diff --git a/go.mod b/go.mod
new file mode 100644
index 0000000..5b42fb2
--- /dev/null
+++ b/go.mod
@@ -0,0 +1,23 @@
+module toastielab.dev/toastie-stuff/otelchi
+
+go 1.22.0
+
+require (
+ github.com/felixge/httpsnoop v1.0.4
+ github.com/go-chi/chi/v5 v5.1.0
+ github.com/stretchr/testify v1.9.0
+ go.opentelemetry.io/otel v1.30.0
+ go.opentelemetry.io/otel/metric v1.30.0
+ go.opentelemetry.io/otel/sdk v1.30.0
+ go.opentelemetry.io/otel/trace v1.30.0
+)
+
+require (
+ github.com/davecgh/go-spew v1.1.1 // indirect
+ github.com/go-logr/logr v1.4.2 // indirect
+ github.com/go-logr/stdr v1.2.2 // indirect
+ github.com/google/uuid v1.6.0 // indirect
+ github.com/pmezard/go-difflib v1.0.0 // indirect
+ golang.org/x/sys v0.25.0 // indirect
+ gopkg.in/yaml.v3 v3.0.1 // indirect
+)
\ No newline at end of file
diff --git a/go.sum b/go.sum
new file mode 100644
index 0000000..0ee495b
--- /dev/null
+++ b/go.sum
@@ -0,0 +1,16 @@
+github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/felixge/httpsnoop v1.0.4/go.mod h1:m8KPJKqk1gH5J9DgRY2ASl2lWCfGKXixSwevea8zH2U=
+github.com/go-chi/chi/v5 v5.1.0/go.mod h1:DslCQbL2OYiznFReuXYUmQ2hGd1aDpCnlMNITLSKoi8=
+github.com/go-logr/logr v1.2.2/go.mod h1:jdQByPbusPIv2/zmleS9BjJVeZ6kBagPoEUsqbVz/1A=
+github.com/go-logr/logr v1.4.2/go.mod h1:9T104GzyrTigFIr8wt5mBrctHMim0Nb2HLGrmQ40KvY=
+github.com/go-logr/stdr v1.2.2/go.mod h1:mMo/vtBO5dYbehREoey6XUKy/eSumjCCveDpRre4VKE=
+github.com/google/uuid v1.6.0/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
+github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
+github.com/stretchr/testify v1.9.0/go.mod h1:r2ic/lqez/lEtzL7wO/rwa5dbSLXVDPFyf8C91i36aY=
+go.opentelemetry.io/otel v1.30.0/go.mod h1:tFw4Br9b7fOS+uEao81PJjVMjW/5fvNCbpsDIXqP0pc=
+go.opentelemetry.io/otel/metric v1.30.0/go.mod h1:aXTfST94tswhWEb+5QjlSqG+cZlmyXy/u8jFpor3WqQ=
+go.opentelemetry.io/otel/sdk v1.30.0/go.mod h1:p14X4Ok8S+sygzblytT1nqG98QG2KYKv++HE0LY/mhg=
+go.opentelemetry.io/otel/trace v1.30.0/go.mod h1:5EyKqTzzmyqB9bwtCCq6pDLktPK6fmGf/Dph+8VI02o=
+golang.org/x/sys v0.25.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
diff --git a/metrics.go b/metrics.go
new file mode 100644
index 0000000..ab678fe
--- /dev/null
+++ b/metrics.go
@@ -0,0 +1,88 @@
+package otelchi
+
+import (
+ "context"
+ "fmt"
+ "time"
+
+ "go.opentelemetry.io/otel/attribute"
+ otelmetric "go.opentelemetry.io/otel/metric"
+)
+
+var (
+ serviceKey = attribute.Key("service")
+ idKey = attribute.Key("id")
+ methodKey = attribute.Key("method")
+ codeKey = attribute.Key("code")
+)
+
+type httpReqProperties struct {
+ Service string
+ ID string
+ Method string
+ Code int
+}
+
+func newMetricsRecorder(meter otelmetric.Meter) *metricsRecorder {
+ httpRequestDurHistogram, err := meter.Int64Histogram("request_duration_seconds")
+ if err != nil {
+ panic(fmt.Sprintf("failed to create request_duration_seconds histogram: %v", err))
+ }
+
+ httpResponseSizeHistogram, err := meter.Int64Histogram("response_size_bytes")
+ if err != nil {
+ panic(fmt.Sprintf("failed to create response_size_bytes histogram: %v", err))
+ }
+
+ httpRequestsInflight, err := meter.Int64UpDownCounter("requests_inflight")
+ if err != nil {
+ panic(fmt.Sprintf("failed to create requests_inflight counter: %v", err))
+ }
+
+ return &metricsRecorder{
+ httpRequestDurHistogram: httpRequestDurHistogram,
+ httpResponseSizeHistogram: httpResponseSizeHistogram,
+ httpRequestsInflight: httpRequestsInflight,
+ }
+}
+
+type metricsRecorder struct {
+ httpRequestDurHistogram otelmetric.Int64Histogram
+ httpResponseSizeHistogram otelmetric.Int64Histogram
+ httpRequestsInflight otelmetric.Int64UpDownCounter
+}
+
+func (r *metricsRecorder) RecordRequestDuration(ctx context.Context, p httpReqProperties, duration time.Duration) {
+ r.httpRequestDurHistogram.Record(ctx,
+ int64(duration.Seconds()),
+ otelmetric.WithAttributes(
+ serviceKey.String(p.Service),
+ idKey.String(p.ID),
+ methodKey.String(p.Method),
+ codeKey.Int(p.Code),
+ ),
+ )
+}
+
+func (r *metricsRecorder) RecordResponseSize(ctx context.Context, p httpReqProperties, size int64) {
+ r.httpResponseSizeHistogram.Record(ctx,
+ size,
+ otelmetric.WithAttributes(
+ serviceKey.String(p.Service),
+ idKey.String(p.ID),
+ methodKey.String(p.Method),
+ codeKey.Int(p.Code),
+ ),
+ )
+}
+
+func (r *metricsRecorder) RecordRequestsInflight(ctx context.Context, p httpReqProperties, count int64) {
+ r.httpRequestsInflight.Add(ctx,
+ count,
+ otelmetric.WithAttributes(
+ serviceKey.String(p.Service),
+ idKey.String(p.ID),
+ methodKey.String(p.Method),
+ ),
+ )
+}
diff --git a/middleware.go b/middleware.go
new file mode 100644
index 0000000..b876106
--- /dev/null
+++ b/middleware.go
@@ -0,0 +1,270 @@
+package otelchi
+
+import (
+ "net/http"
+ "strconv"
+ "sync"
+ "time"
+
+ "github.com/felixge/httpsnoop"
+ "github.com/go-chi/chi/v5"
+
+ "go.opentelemetry.io/otel"
+ "go.opentelemetry.io/otel/propagation"
+
+ otelmetric "go.opentelemetry.io/otel/metric"
+ semconv "go.opentelemetry.io/otel/semconv/v1.20.0"
+ "go.opentelemetry.io/otel/semconv/v1.20.0/httpconv"
+ oteltrace "go.opentelemetry.io/otel/trace"
+)
+
+const (
+ tracerName = "toastielab.dev/toastie-stuff/otelchi"
+)
+
+// Middleware sets up a handler to start tracing the incoming
+// requests. The serverName parameter should describe the name of the
+// (virtual) server handling the request.
+func Middleware(serverName string, opts ...Option) func(http.Handler) http.Handler {
+ cfg := config{}
+ for _, opt := range opts {
+ opt.apply(&cfg)
+ }
+
+ if cfg.TracerProvider == nil {
+ cfg.TracerProvider = otel.GetTracerProvider()
+ }
+ tracer := cfg.TracerProvider.Tracer(
+ tracerName,
+ oteltrace.WithInstrumentationVersion(Version()),
+ )
+
+ if cfg.MeterProvider == nil {
+ cfg.MeterProvider = otel.GetMeterProvider()
+ }
+ meter := cfg.MeterProvider.Meter(
+ tracerName,
+ otelmetric.WithInstrumentationVersion(Version()),
+ )
+
+ if cfg.Propagators == nil {
+ cfg.Propagators = otel.GetTextMapPropagator()
+ }
+
+ return func(handler http.Handler) http.Handler {
+ return &otelware{
+ serverName: serverName,
+ tracer: tracer,
+ meter: meter,
+ recorder: newMetricsRecorder(meter),
+ propagators: cfg.Propagators,
+ handler: handler,
+ chiRoutes: cfg.ChiRoutes,
+ reqMethodInSpanName: cfg.RequestMethodInSpanName,
+ filters: cfg.Filters,
+ traceIDResponseHeaderKey: cfg.TraceIDResponseHeaderKey,
+ traceSampledResponseHeaderKey: cfg.TraceSampledResponseHeaderKey,
+ publicEndpointFn: cfg.PublicEndpointFn,
+ disableMeasureInflight: cfg.DisableMeasureInflight,
+ disableMeasureSize: cfg.DisableMeasureSize,
+ }
+ }
+}
+
+type otelware struct {
+ serverName string
+ tracer oteltrace.Tracer
+ meter otelmetric.Meter
+ recorder *metricsRecorder
+ propagators propagation.TextMapPropagator
+ handler http.Handler
+ chiRoutes chi.Routes
+ reqMethodInSpanName bool
+ filters []Filter
+ traceIDResponseHeaderKey string
+ traceSampledResponseHeaderKey string
+ publicEndpointFn func(r *http.Request) bool
+
+ disableMeasureInflight bool
+ disableMeasureSize bool
+}
+
+type recordingResponseWriter struct {
+ writer http.ResponseWriter
+ written bool
+ writtenBytes int64
+ status int
+}
+
+var rrwPool = &sync.Pool{
+ New: func() interface{} {
+ return &recordingResponseWriter{}
+ },
+}
+
+func getRRW(writer http.ResponseWriter) *recordingResponseWriter {
+ rrw := rrwPool.Get().(*recordingResponseWriter)
+ rrw.written = false
+ rrw.writtenBytes = 0
+ rrw.status = http.StatusOK
+ rrw.writer = httpsnoop.Wrap(writer, httpsnoop.Hooks{
+ Write: func(next httpsnoop.WriteFunc) httpsnoop.WriteFunc {
+ return func(b []byte) (int, error) {
+ if !rrw.written {
+ rrw.written = true
+ rrw.writtenBytes += int64(len(b))
+ }
+ return next(b)
+ }
+ },
+ WriteHeader: func(next httpsnoop.WriteHeaderFunc) httpsnoop.WriteHeaderFunc {
+ return func(statusCode int) {
+ if !rrw.written {
+ rrw.written = true
+ rrw.status = statusCode
+ }
+ next(statusCode)
+ }
+ },
+ })
+ return rrw
+}
+
+func putRRW(rrw *recordingResponseWriter) {
+ rrw.writer = nil
+ rrwPool.Put(rrw)
+}
+
+// ServeHTTP implements the http.Handler interface. It does the actual
+// tracing of the request.
+func (ow *otelware) ServeHTTP(w http.ResponseWriter, r *http.Request) {
+ // go through all filters if any
+ for _, filter := range ow.filters {
+ // if there is a filter that returns false, we skip tracing
+ // and execute next handler
+ if !filter(r) {
+ ow.handler.ServeHTTP(w, r)
+ return
+ }
+ }
+
+ // extract tracing header using propagator
+ ctx := ow.propagators.Extract(r.Context(), propagation.HeaderCarrier(r.Header))
+ // create span, based on specification, we need to set already known attributes
+ // when creating the span, the only thing missing here is HTTP route pattern since
+ // in go-chi/chi route pattern could only be extracted once the request is executed
+ // check here for details:
+ //
+ // https://github.com/go-chi/chi/issues/150#issuecomment-278850733
+ //
+ // if we have access to chi routes, we could extract the route pattern beforehand.
+ spanName := ""
+ routePattern := ""
+ spanAttributes := httpconv.ServerRequest(ow.serverName, r)
+
+ if ow.chiRoutes != nil {
+ rctx := chi.NewRouteContext()
+ if ow.chiRoutes.Match(rctx, r.Method, r.URL.Path) {
+ routePattern = rctx.RoutePattern()
+ spanName = addPrefixToSpanName(ow.reqMethodInSpanName, r.Method, routePattern)
+ spanAttributes = append(spanAttributes, semconv.HTTPRoute(routePattern))
+ }
+ }
+
+ // define span start options
+ spanOpts := []oteltrace.SpanStartOption{
+ oteltrace.WithAttributes(spanAttributes...),
+ oteltrace.WithSpanKind(oteltrace.SpanKindServer),
+ }
+
+ if ow.publicEndpointFn != nil && ow.publicEndpointFn(r) {
+ // mark span as the root span
+ spanOpts = append(spanOpts, oteltrace.WithNewRoot())
+
+ // linking incoming span context to the root span, we need to
+ // ensure if the incoming span context is valid (because it is
+ // possible for us to receive invalid span context due to various
+ // reason such as bug or context propagation error) and it is
+ // coming from another service (remote) before linking it to the
+ // root span
+ spanCtx := oteltrace.SpanContextFromContext(ctx)
+ if spanCtx.IsValid() && spanCtx.IsRemote() {
+ spanOpts = append(
+ spanOpts,
+ oteltrace.WithLinks(oteltrace.Link{
+ SpanContext: spanCtx,
+ }),
+ )
+ }
+ }
+
+ props := httpReqProperties{
+ Service: ow.serverName,
+ ID: routePattern,
+ Method: r.Method,
+ }
+ if routePattern == "" {
+ props.ID = r.URL.Path
+ }
+
+ if !ow.disableMeasureInflight {
+ ow.recorder.RecordRequestsInflight(ctx, props, 1)
+ defer ow.recorder.RecordRequestsInflight(ctx, props, -1)
+ }
+
+ // start span
+ ctx, span := ow.tracer.Start(ctx, spanName, spanOpts...)
+ defer span.End()
+
+ // put trace_id to response header only when `WithTraceIDResponseHeader` is used
+ if len(ow.traceIDResponseHeaderKey) > 0 && span.SpanContext().HasTraceID() {
+ w.Header().Add(ow.traceIDResponseHeaderKey, span.SpanContext().TraceID().String())
+ w.Header().Add(ow.traceSampledResponseHeaderKey, strconv.FormatBool(span.SpanContext().IsSampled()))
+ }
+
+ // get recording response writer
+ rrw := getRRW(w)
+ defer putRRW(rrw)
+
+ // execute next http handler
+ r = r.WithContext(ctx)
+ start := time.Now()
+ ow.handler.ServeHTTP(rrw.writer, r)
+ duration := time.Since(start)
+
+ props.Code = rrw.status
+ ow.recorder.RecordRequestDuration(ctx, props, duration)
+
+ if !ow.disableMeasureSize {
+ ow.recorder.RecordResponseSize(ctx, props, rrw.writtenBytes)
+ }
+
+ // set span name & http route attribute if route pattern cannot be determined
+ // during span creation
+ if len(routePattern) == 0 {
+ routePattern = chi.RouteContext(r.Context()).RoutePattern()
+ span.SetAttributes(semconv.HTTPRoute(routePattern))
+
+ spanName = addPrefixToSpanName(ow.reqMethodInSpanName, r.Method, routePattern)
+ span.SetName(spanName)
+ }
+
+ // set status code attribute
+ span.SetAttributes(semconv.HTTPStatusCode(rrw.status))
+
+ // set span status
+ span.SetStatus(httpconv.ServerStatus(rrw.status))
+}
+
+func addPrefixToSpanName(shouldAdd bool, prefix, spanName string) string {
+ // in chi v5.0.8, the root route will be returned has an empty string
+ // (see https://github.com/go-chi/chi/blob/v5.0.8/context.go#L126)
+ if spanName == "" {
+ spanName = "/"
+ }
+
+ if shouldAdd && len(spanName) > 0 {
+ spanName = prefix + " " + spanName
+ }
+ return spanName
+}
diff --git a/test/cases/middleware_test.go b/test/cases/middleware_test.go
new file mode 100644
index 0000000..41b102c
--- /dev/null
+++ b/test/cases/middleware_test.go
@@ -0,0 +1,150 @@
+package otelchi_test
+
+import (
+ "bufio"
+ "context"
+ "io"
+ "net"
+ "net/http"
+ "net/http/httptest"
+ "testing"
+
+ "github.com/go-chi/chi/v5"
+ "github.com/stretchr/testify/assert"
+ "go.opentelemetry.io/otel"
+ "go.opentelemetry.io/otel/propagation"
+ "go.opentelemetry.io/otel/trace"
+ "toastielab.dev/toastie-stuff/otelchi"
+)
+
+var sc = trace.NewSpanContext(trace.SpanContextConfig{
+ TraceID: [16]byte{1},
+ SpanID: [8]byte{1},
+ Remote: true,
+ TraceFlags: trace.FlagsSampled,
+})
+
+func TestPassthroughSpanFromGlobalTracer(t *testing.T) {
+ var called bool
+ router := chi.NewRouter()
+ router.Use(otelchi.Middleware("foobar"))
+ // The default global TracerProvider provides "pass through" spans for any
+ // span context in the incoming request context.
+ router.HandleFunc("/user/{id}", http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+ called = true
+ got := trace.SpanFromContext(r.Context()).SpanContext()
+ assert.Equal(t, sc, got)
+ w.WriteHeader(http.StatusOK)
+ }))
+
+ r := httptest.NewRequest("GET", "/user/123", nil)
+ r = r.WithContext(trace.ContextWithRemoteSpanContext(context.Background(), sc))
+ w := httptest.NewRecorder()
+
+ router.ServeHTTP(w, r)
+ assert.True(t, called, "failed to run test")
+}
+
+func TestPropagationWithGlobalPropagators(t *testing.T) {
+ defer func(p propagation.TextMapPropagator) {
+ otel.SetTextMapPropagator(p)
+ }(otel.GetTextMapPropagator())
+
+ prop := propagation.TraceContext{}
+ otel.SetTextMapPropagator(prop)
+
+ r := httptest.NewRequest("GET", "/user/123", nil)
+ w := httptest.NewRecorder()
+
+ ctx := trace.ContextWithRemoteSpanContext(context.Background(), sc)
+ otel.GetTextMapPropagator().Inject(ctx, propagation.HeaderCarrier(r.Header))
+
+ var called bool
+ router := chi.NewRouter()
+ router.Use(otelchi.Middleware("foobar"))
+ router.HandleFunc("/user/{id}", http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+ called = true
+ span := trace.SpanFromContext(r.Context())
+ assert.Equal(t, sc, span.SpanContext())
+ w.WriteHeader(http.StatusOK)
+ }))
+
+ router.ServeHTTP(w, r)
+ assert.True(t, called, "failed to run test")
+}
+
+func TestPropagationWithCustomPropagators(t *testing.T) {
+ prop := propagation.TraceContext{}
+
+ r := httptest.NewRequest("GET", "/user/123", nil)
+ w := httptest.NewRecorder()
+
+ ctx := trace.ContextWithRemoteSpanContext(context.Background(), sc)
+ prop.Inject(ctx, propagation.HeaderCarrier(r.Header))
+
+ var called bool
+ router := chi.NewRouter()
+ router.Use(otelchi.Middleware("foobar", otelchi.WithPropagators(prop)))
+ router.HandleFunc("/user/{id}", http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+ called = true
+ span := trace.SpanFromContext(r.Context())
+ assert.Equal(t, sc, span.SpanContext())
+ w.WriteHeader(http.StatusOK)
+ }))
+
+ router.ServeHTTP(w, r)
+ assert.True(t, called, "failed to run test")
+}
+
+func TestResponseWriterInterfaces(t *testing.T) {
+ // make sure the recordingResponseWriter preserves interfaces implemented by the wrapped writer
+ router := chi.NewRouter()
+ router.Use(otelchi.Middleware("foobar"))
+ router.HandleFunc("/user/{id}", http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+ assert.Implements(t, (*http.Hijacker)(nil), w)
+ assert.Implements(t, (*http.Pusher)(nil), w)
+ assert.Implements(t, (*http.Flusher)(nil), w)
+ assert.Implements(t, (*io.ReaderFrom)(nil), w)
+ w.WriteHeader(http.StatusOK)
+ }))
+
+ r := httptest.NewRequest("GET", "/user/123", nil)
+ w := &testResponseWriter{
+ writer: httptest.NewRecorder(),
+ }
+
+ router.ServeHTTP(w, r)
+}
+
+type testResponseWriter struct {
+ writer http.ResponseWriter
+}
+
+func (rw *testResponseWriter) Header() http.Header {
+ return rw.writer.Header()
+}
+func (rw *testResponseWriter) Write(b []byte) (int, error) {
+ return rw.writer.Write(b)
+}
+func (rw *testResponseWriter) WriteHeader(statusCode int) {
+ rw.writer.WriteHeader(statusCode)
+}
+
+// implement Hijacker
+func (rw *testResponseWriter) Hijack() (net.Conn, *bufio.ReadWriter, error) {
+ return nil, nil, nil
+}
+
+// implement Pusher
+func (rw *testResponseWriter) Push(target string, opts *http.PushOptions) error {
+ return nil
+}
+
+// implement Flusher
+func (rw *testResponseWriter) Flush() {
+}
+
+// implement io.ReaderFrom
+func (rw *testResponseWriter) ReadFrom(r io.Reader) (n int64, err error) {
+ return 0, nil
+}
diff --git a/test/cases/sdk_test.go b/test/cases/sdk_test.go
new file mode 100644
index 0000000..57c1604
--- /dev/null
+++ b/test/cases/sdk_test.go
@@ -0,0 +1,782 @@
+package otelchi_test
+
+import (
+ "context"
+ "fmt"
+ "net/http"
+ "net/http/httptest"
+ "testing"
+
+ "github.com/go-chi/chi/v5"
+ "github.com/stretchr/testify/assert"
+ "github.com/stretchr/testify/require"
+ "go.opentelemetry.io/otel/attribute"
+ "go.opentelemetry.io/otel/propagation"
+ sdktrace "go.opentelemetry.io/otel/sdk/trace"
+ "go.opentelemetry.io/otel/sdk/trace/tracetest"
+ "go.opentelemetry.io/otel/trace"
+ "toastielab.dev/toastie-stuff/otelchi"
+)
+
+func TestSDKIntegration(t *testing.T) {
+ // prepare router and span recorder
+ router, sr := newSDKTestRouter("foobar", false)
+
+ // define routes
+ router.HandleFunc("/user/{id:[0-9]+}", ok)
+ router.HandleFunc("/book/{title}", ok)
+
+ // execute requests
+ reqs := []*http.Request{
+ httptest.NewRequest("GET", "/user/123", nil),
+ httptest.NewRequest("GET", "/book/foo", nil),
+ }
+ executeRequests(router, reqs)
+
+ // get recorded spans
+ recordedSpans := sr.Ended()
+
+ // ensure that we have 2 recorded spans
+ require.Len(t, recordedSpans, len(reqs))
+
+ // ensure span values
+ checkSpans(t, recordedSpans, []spanValueCheck{
+ {
+ Name: "/user/{id:[0-9]+}",
+ Kind: trace.SpanKindServer,
+ Attributes: getSemanticAttributes(
+ "foobar",
+ http.StatusOK,
+ "GET",
+ "/user/{id:[0-9]+}",
+ ),
+ },
+ {
+ Name: "/book/{title}",
+ Kind: trace.SpanKindServer,
+ Attributes: getSemanticAttributes(
+ "foobar",
+ http.StatusOK,
+ "GET",
+ "/book/{title}",
+ ),
+ },
+ })
+}
+
+func TestSDKIntegrationWithFilter(t *testing.T) {
+ // prepare test cases
+ serviceName := "foobar"
+ testCases := []struct {
+ Name string
+ FilterFn []otelchi.Filter
+ LenSpans int
+ ExpectedRouteNames []string
+ }{
+ {
+ Name: "One WithFilter",
+ FilterFn: []otelchi.Filter{
+ func(r *http.Request) bool {
+ return r.URL.Path != "/live" && r.URL.Path != "/ready"
+ },
+ },
+ LenSpans: 2,
+ ExpectedRouteNames: []string{"/user/{id:[0-9]+}", "/book/{title}"},
+ },
+ {
+ Name: "Multiple WithFilter",
+ FilterFn: []otelchi.Filter{
+ func(r *http.Request) bool {
+ return r.URL.Path != "/ready"
+ },
+ func(r *http.Request) bool {
+ return r.URL.Path != "/live"
+ },
+ },
+ LenSpans: 2,
+ ExpectedRouteNames: []string{"/user/{id:[0-9]+}", "/book/{title}"},
+ },
+ {
+ Name: "All Routes are traced",
+ FilterFn: []otelchi.Filter{
+ func(r *http.Request) bool {
+ return true
+ },
+ },
+ LenSpans: 4,
+ ExpectedRouteNames: []string{"/user/{id:[0-9]+}", "/book/{title}", "/live", "/ready"},
+ },
+ {
+ Name: "All Routes are not traced",
+ FilterFn: []otelchi.Filter{
+ func(r *http.Request) bool {
+ return false
+ },
+ },
+ LenSpans: 0,
+ ExpectedRouteNames: []string{},
+ },
+ }
+
+ // execute test cases
+ for _, testCase := range testCases {
+ t.Run(testCase.Name, func(t *testing.T) {
+ // prepare router and span recorder
+ filters := []otelchi.Option{}
+ for _, filter := range testCase.FilterFn {
+ filters = append(filters, otelchi.WithFilter(filter))
+ }
+ router, sr := newSDKTestRouter(serviceName, false, filters...)
+
+ // define router
+ router.HandleFunc("/user/{id:[0-9]+}", ok)
+ router.HandleFunc("/book/{title}", ok)
+ router.HandleFunc("/health", ok)
+ router.HandleFunc("/live", ok)
+ router.HandleFunc("/ready", ok)
+
+ // execute requests
+ executeRequests(router, []*http.Request{
+ httptest.NewRequest("GET", "/user/123", nil),
+ httptest.NewRequest("GET", "/book/foo", nil),
+ httptest.NewRequest("GET", "/live", nil),
+ httptest.NewRequest("GET", "/ready", nil),
+ })
+
+ // check recorded spans
+ recordedSpans := sr.Ended()
+ require.Len(t, recordedSpans, testCase.LenSpans)
+
+ // ensure span values
+ spanValues := []spanValueCheck{}
+ for _, routeName := range testCase.ExpectedRouteNames {
+ spanValues = append(spanValues, spanValueCheck{
+ Name: routeName,
+ Kind: trace.SpanKindServer,
+ Attributes: getSemanticAttributes(
+ serviceName,
+ http.StatusOK,
+ "GET",
+ routeName,
+ ),
+ })
+ }
+ checkSpans(t, recordedSpans, spanValues)
+ })
+ }
+
+}
+
+func TestSDKIntegrationWithChiRoutes(t *testing.T) {
+ // define router & span recorder
+ router, sr := newSDKTestRouter("foobar", true)
+
+ // define route
+ router.HandleFunc("/user/{id:[0-9]+}", ok)
+ router.HandleFunc("/book/{title}", ok)
+
+ // execute requests
+ reqs := []*http.Request{
+ httptest.NewRequest("GET", "/user/123", nil),
+ httptest.NewRequest("GET", "/book/foo", nil),
+ }
+ executeRequests(router, reqs)
+
+ // get recorded spans
+ recordedSpans := sr.Ended()
+
+ // ensure that we have 2 recorded spans
+ require.Len(t, recordedSpans, len(reqs))
+
+ // ensure span values
+ checkSpans(t, recordedSpans, []spanValueCheck{
+ {
+ Name: "/user/{id:[0-9]+}",
+ Kind: trace.SpanKindServer,
+ Attributes: getSemanticAttributes(
+ "foobar",
+ http.StatusOK,
+ "GET",
+ "/user/{id:[0-9]+}",
+ ),
+ },
+ {
+ Name: "/book/{title}",
+ Kind: trace.SpanKindServer,
+ Attributes: getSemanticAttributes(
+ "foobar",
+ http.StatusOK,
+ "GET",
+ "/book/{title}",
+ ),
+ },
+ })
+}
+
+func TestSDKIntegrationOverrideSpanName(t *testing.T) {
+ // prepare test router and span recorder
+ router, sr := newSDKTestRouter("foobar", true)
+
+ // define route
+ router.HandleFunc("/user/{id:[0-9]+}", func(w http.ResponseWriter, r *http.Request) {
+ span := trace.SpanFromContext(r.Context())
+ span.SetName("overriden span name")
+ w.WriteHeader(http.StatusOK)
+ })
+ router.HandleFunc("/book/{title}", ok)
+
+ // execute requests
+ reqs := []*http.Request{
+ httptest.NewRequest("GET", "/user/123", nil),
+ httptest.NewRequest("GET", "/book/foo", nil),
+ }
+ executeRequests(router, reqs)
+
+ // get recorded spans
+ recordedSpans := sr.Ended()
+
+ // ensure the number of spans is correct
+ require.Len(t, sr.Ended(), len(reqs))
+
+ // check span values
+ checkSpans(t, recordedSpans, []spanValueCheck{
+ {
+ Name: "overriden span name",
+ Kind: trace.SpanKindServer,
+ Attributes: getSemanticAttributes(
+ "foobar",
+ http.StatusOK,
+ "GET",
+ "/user/{id:[0-9]+}",
+ ),
+ },
+ {
+ Name: "/book/{title}",
+ Kind: trace.SpanKindServer,
+ Attributes: getSemanticAttributes(
+ "foobar",
+ http.StatusOK,
+ "GET",
+ "/book/{title}",
+ ),
+ },
+ })
+}
+
+func TestSDKIntegrationWithRequestMethodInSpanName(t *testing.T) {
+ // prepare router & span recorder
+ router, sr := newSDKTestRouter("foobar", true, otelchi.WithRequestMethodInSpanName(true))
+
+ // define handler
+ router.HandleFunc("/user/{id:[0-9]+}", ok)
+ router.HandleFunc("/book/{title}", ok)
+
+ // execute requests
+ reqs := []*http.Request{
+ httptest.NewRequest("GET", "/user/123", nil),
+ httptest.NewRequest("GET", "/book/foo", nil),
+ }
+ executeRequests(router, reqs)
+
+ // get recorded spans & ensure the number is correct
+ recordedSpans := sr.Ended()
+ require.Len(t, sr.Ended(), len(reqs))
+
+ // check span values
+ checkSpans(t, recordedSpans, []spanValueCheck{
+ {
+ Name: "GET /user/{id:[0-9]+}",
+ Kind: trace.SpanKindServer,
+ Attributes: getSemanticAttributes(
+ "foobar",
+ http.StatusOK,
+ "GET",
+ "/user/{id:[0-9]+}",
+ ),
+ },
+ {
+ Name: "GET /book/{title}",
+ Kind: trace.SpanKindServer,
+ Attributes: getSemanticAttributes(
+ "foobar",
+ http.StatusOK,
+ "GET",
+ "/book/{title}",
+ ),
+ },
+ })
+}
+
+func TestSDKIntegrationEmptyHandlerDefaultStatusCode(t *testing.T) {
+ // prepare router and span recorder
+ router, sr := newSDKTestRouter("foobar", false)
+
+ // define routes
+ router.HandleFunc("/user/{id:[0-9]+}", func(w http.ResponseWriter, r *http.Request) {})
+ router.HandleFunc("/book/{title}", func(w http.ResponseWriter, r *http.Request) {})
+ router.HandleFunc("/not-found", http.NotFound)
+
+ // execute requests
+ reqs := []*http.Request{
+ httptest.NewRequest("GET", "/user/123", nil),
+ httptest.NewRequest("GET", "/book/foo", nil),
+ httptest.NewRequest("GET", "/not-found", nil),
+ }
+ executeRequests(router, reqs)
+
+ // get recorded spans
+ recordedSpans := sr.Ended()
+
+ // ensure that we have 3 recorded spans
+ require.Len(t, recordedSpans, len(reqs))
+
+ // ensure span values
+ checkSpans(t, recordedSpans, []spanValueCheck{
+ {
+ Name: "/user/{id:[0-9]+}",
+ Kind: trace.SpanKindServer,
+ Attributes: getSemanticAttributes(
+ "foobar",
+ http.StatusOK,
+ "GET",
+ "/user/{id:[0-9]+}",
+ ),
+ },
+ {
+ Name: "/book/{title}",
+ Kind: trace.SpanKindServer,
+ Attributes: getSemanticAttributes(
+ "foobar",
+ http.StatusOK,
+ "GET",
+ "/book/{title}",
+ ),
+ },
+ {
+ Name: "/not-found",
+ Kind: trace.SpanKindServer,
+ Attributes: getSemanticAttributes(
+ "foobar",
+ http.StatusNotFound,
+ "GET",
+ "/not-found",
+ ),
+ },
+ })
+}
+
+func TestSDKIntegrationRootHandler(t *testing.T) {
+ // prepare router and span recorder
+ router, sr := newSDKTestRouter("foobar", true)
+
+ // define routes
+ router.HandleFunc("/", ok)
+
+ // execute requests
+ reqs := []*http.Request{
+ httptest.NewRequest("GET", "/", nil),
+ }
+ executeRequests(router, reqs)
+
+ // get recorded spans
+ recordedSpans := sr.Ended()
+
+ // ensure that we have 1 recorded span
+ require.Len(t, recordedSpans, 1)
+
+ // ensure span values
+ checkSpans(t, recordedSpans, []spanValueCheck{
+ {
+ Name: "/",
+ Kind: trace.SpanKindServer,
+ Attributes: getSemanticAttributes(
+ "foobar",
+ http.StatusOK,
+ "GET",
+ "/",
+ ),
+ },
+ })
+}
+
+func TestSDKIntegrationWithTraceIDResponseHeader(t *testing.T) {
+ // prepare both sampled & non-sampled span context
+ spanCtxSampled := trace.NewSpanContext(trace.SpanContextConfig{
+ TraceID: [16]byte{1},
+ SpanID: [8]byte{1},
+ Remote: true,
+ TraceFlags: trace.FlagsSampled,
+ })
+ spanCtxNotSampled := trace.NewSpanContext(trace.SpanContextConfig{
+ TraceID: [16]byte{2},
+ SpanID: [8]byte{2},
+ Remote: true,
+ TraceFlags: 0,
+ })
+
+ // define custom header key function
+ customHeaderKeyFunc := func() string {
+ return "X-Custom-Trace-ID"
+ }
+
+ // define test cases
+ testCases := []struct {
+ Name string
+ HeaderKeyFunc func() string
+ SpanContext trace.SpanContext
+ ExpTraceResponseIDKey string
+ ExpTraceResponseSampledKeyVal bool
+ }{
+ {
+ Name: "Default Header Key, Trace Sampled",
+ HeaderKeyFunc: nil,
+ SpanContext: spanCtxSampled,
+ ExpTraceResponseIDKey: otelchi.DefaultTraceIDResponseHeaderKey,
+ ExpTraceResponseSampledKeyVal: true,
+ },
+ {
+ Name: "Default Header Key, Trace Not Sampled",
+ HeaderKeyFunc: nil,
+ SpanContext: spanCtxNotSampled,
+ ExpTraceResponseIDKey: otelchi.DefaultTraceIDResponseHeaderKey,
+ ExpTraceResponseSampledKeyVal: false,
+ },
+ {
+ Name: "Custom Header Key, Trace Sampled",
+ HeaderKeyFunc: customHeaderKeyFunc,
+ SpanContext: spanCtxSampled,
+ ExpTraceResponseIDKey: customHeaderKeyFunc(),
+ ExpTraceResponseSampledKeyVal: true,
+ },
+ {
+ Name: "Custom Header Key, Trace Not Sampled",
+ HeaderKeyFunc: customHeaderKeyFunc,
+ SpanContext: spanCtxNotSampled,
+ ExpTraceResponseIDKey: customHeaderKeyFunc(),
+ ExpTraceResponseSampledKeyVal: false,
+ },
+ }
+ for _, testCase := range testCases {
+ t.Run(testCase.Name, func(t *testing.T) {
+ // configure router
+ router := chi.NewRouter()
+ router.Use(
+ otelchi.Middleware(
+ "foobar",
+ otelchi.WithChiRoutes(router),
+ otelchi.WithTraceIDResponseHeader(testCase.HeaderKeyFunc),
+ ),
+ )
+ router.HandleFunc("/user/{id:[0-9]+}", ok)
+ router.HandleFunc("/book/{title}", ok)
+
+ // execute requests
+ r0 := httptest.NewRequest("GET", "/user/123", nil)
+ r0 = r0.WithContext(trace.ContextWithRemoteSpanContext(context.Background(), testCase.SpanContext))
+ w := httptest.NewRecorder()
+ router.ServeHTTP(w, r0)
+
+ // check response headers
+ require.Equal(t, testCase.SpanContext.TraceID().String(), w.Header().Get(testCase.ExpTraceResponseIDKey))
+ require.Equal(t, fmt.Sprintf("%v", testCase.ExpTraceResponseSampledKeyVal), w.Header().Get(otelchi.DefaultTraceSampledResponseHeaderKey))
+ })
+ }
+}
+
+func TestSDKIntegrationWithTraceResponseHeaders(t *testing.T) {
+ // prepare both sampled & non-sampled span context
+ spanCtxSampled := trace.NewSpanContext(trace.SpanContextConfig{
+ TraceID: [16]byte{1},
+ SpanID: [8]byte{1},
+ Remote: true,
+ TraceFlags: trace.FlagsSampled,
+ })
+ spanCtxNotSampled := trace.NewSpanContext(trace.SpanContextConfig{
+ TraceID: [16]byte{2},
+ SpanID: [8]byte{2},
+ Remote: true,
+ TraceFlags: 0,
+ })
+
+ // define test cases
+ testCases := []struct {
+ Name string
+ TraceHeaderConfig otelchi.TraceHeaderConfig
+ SpanContext trace.SpanContext
+ ExpTraceResponseIDKey string
+ ExpTraceResponseSampledKey string
+ ExpTraceResponseSampledKeyVal bool
+ }{
+ {
+ Name: "Default Trace Config, Trace Sampled",
+ TraceHeaderConfig: otelchi.TraceHeaderConfig{},
+ SpanContext: spanCtxSampled,
+ ExpTraceResponseIDKey: otelchi.DefaultTraceIDResponseHeaderKey,
+ ExpTraceResponseSampledKey: otelchi.DefaultTraceSampledResponseHeaderKey,
+ ExpTraceResponseSampledKeyVal: true,
+ },
+ {
+ Name: "Default Trace Config, Trace Not Sampled",
+ TraceHeaderConfig: otelchi.TraceHeaderConfig{},
+ SpanContext: spanCtxNotSampled,
+ ExpTraceResponseIDKey: otelchi.DefaultTraceIDResponseHeaderKey,
+ ExpTraceResponseSampledKey: otelchi.DefaultTraceSampledResponseHeaderKey,
+ ExpTraceResponseSampledKeyVal: false,
+ },
+ {
+ Name: "Custom Trace Config, Trace Sampled",
+ TraceHeaderConfig: otelchi.TraceHeaderConfig{
+ TraceIDHeader: "X-Custom-Trace-ID",
+ TraceSampledHeader: "X-Custom-Trace-Sampled",
+ },
+ SpanContext: spanCtxSampled,
+ ExpTraceResponseIDKey: "X-Custom-Trace-ID",
+ ExpTraceResponseSampledKey: "X-Custom-Trace-Sampled",
+ ExpTraceResponseSampledKeyVal: true,
+ },
+ {
+ Name: "Custom Trace Config, Trace Not Sampled",
+ TraceHeaderConfig: otelchi.TraceHeaderConfig{
+ TraceIDHeader: "X-Custom-Trace-ID",
+ TraceSampledHeader: "X-Custom-Trace-Sampled",
+ },
+ SpanContext: spanCtxNotSampled,
+ ExpTraceResponseIDKey: "X-Custom-Trace-ID",
+ ExpTraceResponseSampledKey: "X-Custom-Trace-Sampled",
+ ExpTraceResponseSampledKeyVal: false,
+ },
+ }
+ for _, testCase := range testCases {
+ t.Run(testCase.Name, func(t *testing.T) {
+ // configure router
+ router := chi.NewRouter()
+ router.Use(
+ otelchi.Middleware(
+ "foobar",
+ otelchi.WithChiRoutes(router),
+ otelchi.WithTraceResponseHeaders(testCase.TraceHeaderConfig),
+ ),
+ )
+ router.HandleFunc("/user/{id:[0-9]+}", ok)
+ router.HandleFunc("/book/{title}", ok)
+
+ // execute requests
+ r0 := httptest.NewRequest("GET", "/user/123", nil)
+ r0 = r0.WithContext(trace.ContextWithRemoteSpanContext(context.Background(), testCase.SpanContext))
+ w := httptest.NewRecorder()
+ router.ServeHTTP(w, r0)
+
+ // check response headers
+ require.Equal(t, testCase.SpanContext.TraceID().String(), w.Header().Get(testCase.ExpTraceResponseIDKey))
+ require.Equal(t, fmt.Sprintf("%v", testCase.ExpTraceResponseSampledKeyVal), w.Header().Get(testCase.ExpTraceResponseSampledKey))
+ })
+ }
+}
+
+func TestWithPublicEndpoint(t *testing.T) {
+ // prepare router and span recorder
+ router, spanRecorder := newSDKTestRouter("foobar", true, otelchi.WithPublicEndpoint())
+
+ // prepare remote span context
+ remoteSpanCtx := trace.NewSpanContext(trace.SpanContextConfig{
+ TraceID: trace.TraceID{0x01},
+ SpanID: trace.SpanID{0x01},
+ Remote: true,
+ })
+
+ // prepare http request & inject remote span context into it
+ endpointURL := "/with/public/endpoint"
+ req := httptest.NewRequest(http.MethodGet, endpointURL, nil)
+ ctx := trace.ContextWithSpanContext(context.Background(), remoteSpanCtx)
+ (propagation.TraceContext{}).Inject(ctx, propagation.HeaderCarrier(req.Header))
+
+ // configure router handler
+ router.HandleFunc(endpointURL, func(w http.ResponseWriter, r *http.Request) {
+ // get span from request context
+ span := trace.SpanFromContext(r.Context())
+ spanCtx := span.SpanContext()
+
+ // ensure it is not equal to the remote span context
+ require.False(t, spanCtx.Equal(remoteSpanCtx))
+ require.True(t, spanCtx.IsValid())
+ require.False(t, spanCtx.IsRemote())
+ })
+
+ // execute http request
+ executeRequests(router, []*http.Request{req})
+
+ // get recorded spans
+ recordedSpans := spanRecorder.Ended()
+ require.Len(t, recordedSpans, 1)
+
+ links := recordedSpans[0].Links()
+ require.Len(t, links, 1)
+ require.True(t, remoteSpanCtx.Equal(links[0].SpanContext))
+}
+
+func TestWithPublicEndpointFn(t *testing.T) {
+ // prepare remote span context
+ remoteSpanCtx := trace.NewSpanContext(trace.SpanContextConfig{
+ TraceID: trace.TraceID{0x01},
+ SpanID: trace.SpanID{0x01},
+ Remote: true,
+ })
+
+ // prepare test cases
+ testCases := []struct {
+ Name string
+ Fn func(r *http.Request) bool
+ HandlerAssert func(t *testing.T, spanCtx trace.SpanContext)
+ SpansAssert func(t *testing.T, spanCtx trace.SpanContext, spans []sdktrace.ReadOnlySpan)
+ }{
+ {
+ Name: "Function Always Return True",
+ Fn: func(r *http.Request) bool { return true },
+ HandlerAssert: func(t *testing.T, spanCtx trace.SpanContext) {
+ // ensure it is not equal to the remote span context
+ require.False(t, spanCtx.Equal(remoteSpanCtx))
+ require.True(t, spanCtx.IsValid())
+
+ // ensure it is not remote span
+ require.False(t, spanCtx.IsRemote())
+ },
+ SpansAssert: func(t *testing.T, spanCtx trace.SpanContext, spans []sdktrace.ReadOnlySpan) {
+ // ensure spans length
+ require.Len(t, spans, 1)
+
+ // ensure the span has been linked
+ links := spans[0].Links()
+ require.Len(t, links, 1)
+ require.True(t, remoteSpanCtx.Equal(links[0].SpanContext))
+ },
+ },
+ {
+ Name: "Function Always Return False",
+ Fn: func(r *http.Request) bool { return false },
+ HandlerAssert: func(t *testing.T, spanCtx trace.SpanContext) {
+ // ensure the span is child of the remote span
+ require.Equal(t, remoteSpanCtx.TraceID(), spanCtx.TraceID())
+ require.True(t, spanCtx.IsValid())
+
+ // ensure it is not remote span
+ require.False(t, spanCtx.IsRemote())
+ },
+ SpansAssert: func(t *testing.T, spanCtx trace.SpanContext, spans []sdktrace.ReadOnlySpan) {
+ // ensure spans length
+ require.Len(t, spans, 1, "unexpected span length")
+
+ // ensure the span has no links
+ links := spans[0].Links()
+ require.Len(t, links, 0)
+ },
+ },
+ }
+
+ // execute test cases
+ for _, testCase := range testCases {
+ t.Run(testCase.Name, func(t *testing.T) {
+
+ // prepare router and span recorder
+ router, spanRecorder := newSDKTestRouter(
+ "foobar",
+ true,
+ otelchi.WithPublicEndpointFn(testCase.Fn),
+ )
+
+ // prepare http request & inject remote span context into it
+ endpointURL := "/with/public/endpoint"
+ req := httptest.NewRequest(http.MethodGet, endpointURL, nil)
+ ctx := trace.ContextWithSpanContext(context.Background(), remoteSpanCtx)
+ (propagation.TraceContext{}).Inject(ctx, propagation.HeaderCarrier(req.Header))
+
+ // configure router handler
+ router.HandleFunc(endpointURL, func(w http.ResponseWriter, r *http.Request) {
+ // assert handler
+ span := trace.SpanFromContext(r.Context())
+ testCase.HandlerAssert(t, span.SpanContext())
+ })
+
+ // execute http request
+ executeRequests(router, []*http.Request{req})
+
+ // assert recorded spans
+ testCase.SpansAssert(t, remoteSpanCtx, spanRecorder.Ended())
+ })
+ }
+}
+
+func assertSpan(t *testing.T, span sdktrace.ReadOnlySpan, name string, kind trace.SpanKind, attrs ...attribute.KeyValue) {
+ t.Helper()
+
+ assert.Equal(t, name, span.Name())
+ assert.Equal(t, kind, span.SpanKind())
+
+ got := make(map[attribute.Key]attribute.Value, len(span.Attributes()))
+ for _, a := range span.Attributes() {
+ got[a.Key] = a.Value
+ }
+ for _, want := range attrs {
+ if !assert.Contains(t, got, want.Key) {
+ continue
+ }
+ assert.Equal(t, want.Value, got[want.Key])
+ }
+}
+
+func ok(w http.ResponseWriter, _ *http.Request) {
+ w.WriteHeader(http.StatusOK)
+}
+
+func newSDKTestRouter(serverName string, withChiRoutes bool, opts ...otelchi.Option) (*chi.Mux, *tracetest.SpanRecorder) {
+ spanRecorder := tracetest.NewSpanRecorder()
+ tracerProvider := sdktrace.NewTracerProvider(
+ // set the tracer provider to always sample trace, this is important
+ // because if we don't set this, sometimes there are traces that
+ // won't be sampled (recorded), so we need to set this option
+ // to ensure every trace in this test is recorded.
+ sdktrace.WithSampler(sdktrace.AlwaysSample()),
+ )
+ tracerProvider.RegisterSpanProcessor(spanRecorder)
+
+ opts = append(opts, otelchi.WithTracerProvider(tracerProvider))
+
+ router := chi.NewRouter()
+ if withChiRoutes {
+ opts = append(opts, otelchi.WithChiRoutes(router))
+ }
+ router.Use(otelchi.Middleware(serverName, opts...))
+
+ return router, spanRecorder
+}
+
+type spanValueCheck struct {
+ Name string
+ Kind trace.SpanKind
+ Attributes []attribute.KeyValue
+}
+
+func getSemanticAttributes(serverName string, httpStatusCode int, httpMethod, httpRoute string) []attribute.KeyValue {
+ return []attribute.KeyValue{
+ attribute.String("net.host.name", serverName),
+ attribute.Int("http.status_code", httpStatusCode),
+ attribute.String("http.method", httpMethod),
+ attribute.String("http.route", httpRoute),
+ }
+}
+
+func checkSpans(t *testing.T, spans []sdktrace.ReadOnlySpan, valueChecks []spanValueCheck) {
+ t.Helper()
+
+ for i := 0; i < len(spans); i++ {
+ span := spans[i]
+ valueCheck := valueChecks[i]
+ assertSpan(t, span, valueCheck.Name, valueCheck.Kind, valueCheck.Attributes...)
+ }
+}
+
+func executeRequests(router *chi.Mux, reqs []*http.Request) {
+ w := httptest.NewRecorder()
+ for _, r := range reqs {
+ router.ServeHTTP(w, r)
+ }
+}
diff --git a/test/cases/version_test.go b/test/cases/version_test.go
new file mode 100644
index 0000000..954be46
--- /dev/null
+++ b/test/cases/version_test.go
@@ -0,0 +1,20 @@
+package otelchi_test
+
+import (
+ "regexp"
+ "testing"
+
+ "github.com/stretchr/testify/assert"
+ "toastielab.dev/toastie-stuff/otelchi"
+)
+
+// regex taken from https://semver.org/#is-there-a-suggested-regular-expression-regex-to-check-a-semver-string
+var versionRegex = regexp.MustCompile(`^(0|[1-9]\d*)\.(0|[1-9]\d*)\.(0|[1-9]\d*)` +
+ `(?:-((?:0|[1-9]\d*|\d*[a-zA-Z-][0-9a-zA-Z-]*)` +
+ `(?:\.(?:0|[1-9]\d*|\d*[a-zA-Z-][0-9a-zA-Z-]*))*))?` +
+ `(?:\+([0-9a-zA-Z-]+(?:\.[0-9a-zA-Z-]+)*))?$`)
+
+func TestVersionSemver(t *testing.T) {
+ v := otelchi.Version()
+ assert.NotNil(t, versionRegex.FindStringSubmatch(v), "version is not semver: %s", v)
+}
diff --git a/test/infras/Dockerfile b/test/infras/Dockerfile
new file mode 100644
index 0000000..7a8c9cc
--- /dev/null
+++ b/test/infras/Dockerfile
@@ -0,0 +1,34 @@
+FROM debian:10.13
+
+RUN apt-get update && apt-get install -y \
+ gcc \
+ curl \
+ git \
+ unzip \
+ wget \
+ make \
+ && rm -rf /var/lib/apt/lists/*
+
+# Install Gobrew
+ENV PATH="/root/.gobrew/current/bin:/root/.gobrew/bin:$PATH"
+RUN curl -sL https://raw.githubusercontent.com/kevincobain2000/gobrew/v1.10.11/git.io.sh | bash
+
+# Set Working Directory
+WORKDIR /go/src/toastielab.dev/toastie-stuff/otelchi
+
+# Install Multiple Go Versions
+ARG GO_VERSIONS
+COPY ./test/infras/install_go.sh ./test/infras/
+RUN chmod +x ./test/infras/install_go.sh && sh ./test/infras/install_go.sh
+
+COPY go.mod go.sum ./
+RUN go mod download -x
+
+COPY ./test/infras/entrypoint.sh ./test/infras/
+RUN chmod +x ./test/infras/entrypoint.sh
+
+ENV GO_VERSIONS=$GO_VERSIONS
+
+COPY . .
+
+ENTRYPOINT [ "./test/infras/entrypoint.sh" ]
\ No newline at end of file
diff --git a/test/infras/entrypoint.sh b/test/infras/entrypoint.sh
new file mode 100644
index 0000000..aaf4f42
--- /dev/null
+++ b/test/infras/entrypoint.sh
@@ -0,0 +1,18 @@
+#!/bin/sh
+
+# Terminate script immediately on any errors
+set -e
+
+# Define Go versions
+go_versions=${GO_VERSIONS}
+
+echo ${GO_VERSIONS}
+
+# Iterate over each version
+for version in $go_versions; do
+ # Set Go version using gobrew
+ gobrew use "$version"
+
+ # Execute Test as defined in the Makefile
+ make go-test
+done
\ No newline at end of file
diff --git a/test/infras/install_go.sh b/test/infras/install_go.sh
new file mode 100644
index 0000000..19feb43
--- /dev/null
+++ b/test/infras/install_go.sh
@@ -0,0 +1,9 @@
+#!/bin/sh
+
+# Define Go versions
+go_versions=${GO_VERSIONS}
+
+# Install each Go version using gobrew
+for version in $go_versions; do
+ gobrew install "$version"
+done
\ No newline at end of file
diff --git a/version.go b/version.go
new file mode 100644
index 0000000..8ab8ec4
--- /dev/null
+++ b/version.go
@@ -0,0 +1,6 @@
+package otelchi
+
+// Version is the current release version of otelchi in use.
+func Version() string {
+ return "0.10.0"
+}