Go

1. Prerequisites

Go 1.17+ Check with:

1go version

• Middleware Host Agent on the same machine (host-based only). If your app is in containers/Kubernetes, set MW_AGENT_SERVICE so your app can reach the Host Agent.
  • Docker: MW_AGENT_SERVICE should point to the Docker bridge gateway (default 172.17.0.1).
  • Kubernetes: MW_AGENT_SERVICE=mw-service.mw-agent-ns.svc.cluster.local.

2. Install the Go APM package

1go get github.com/middleware-labs/golang-apm@latest
2
3Add imports at your entry point (first import block):
4import (
5  track "github.com/middleware-labs/golang-apm/tracker"
6)

The accessToken is your MW account key (see Installation page in the app).

3. Instrumentation

Pick Host (with the Host Agent) or Serverless (send directly to Middleware). In both cases, you initialise once at startup with track.Track(...).

1// main.go (in func main)
2config, err := track.Track(
3  track.WithConfigTag("service", "YOUR_SERVICE_NAME"),
4  track.WithConfigTag("accessToken", "<MW_API_KEY>"), // optional in Host mode
5)
6if err != nil { panic(err) }
7defer func() { _ = config.Tp.Shutdown(context.Background()) }()

1config, err := track.Track(
2  track.WithConfigTag("service", "YOUR_SERVICE_NAME"),
3  track.WithConfigTag("accessToken", "<MW_API_KEY>"),
4  track.WithConfigTag("target", "https://<MW_UID>.middleware.io:443"),
5)
6if err != nil { panic(err) }
7defer func() { _ = config.Tp.Shutdown(context.Background()) }()

4. Framework quick-starts

1go get github.com/middleware-labs/golang-apm-http
2
3import (
4  "net/http"
5  track "github.com/middleware-labs/golang-apm/tracker"
6  mwhttp "github.com/middleware-labs/golang-apm-http/http"
7)
8
9func main() {
10  go track.Track(
11    track.WithConfigTag(track.Service, "your service"),
12    track.WithConfigTag(track.Token,   "<MW_API_KEY>"),
13  )
14  http.Handle("/hello", mwhttp.MiddlewareHandler(http.HandlerFunc(hello), "hello"))
15}

1go get github.com/middleware-labs/golang-apm-gin@latest
2
3import (
4  "github.com/gin-gonic/gin"
5  track "github.com/middleware-labs/golang-apm/tracker"
6  mwgin "github.com/middleware-labs/golang-apm-gin/gin"
7)
8
9func main() {
10  r := gin.Default()
11  config, _ := track.Track(
12    track.WithConfigTag("service","<apm-service>"),
13    track.WithConfigTag("accessToken","<MW_API_KEY>"),
14  )
15  r.Use(mwgin.Middleware(config))
16}

1go get github.com/middleware-labs/golang-apm-mux@latest
2
3import (
4  "github.com/gorilla/mux"
5  track "github.com/middleware-labs/golang-apm/tracker"
6  mwmux "github.com/middleware-labs/golang-apm-mux/mux"
7)
8
9func main() {
10  r := mux.NewRouter()
11  config, _ := track.Track(
12    track.WithConfigTag("service","<apm-service>"),
13    track.WithConfigTag("accessToken","<MW_API_KEY>"),
14  )
15  r.Use(mwmux.Middleware(config))
16}

1go get github.com/middleware-labs/agent-apm-go-chi-legacy@latest
2
3import (
4  "github.com/go-chi/chi"
5  track "github.com/middleware-labs/golang-apm/tracker"
6  mwchi "github.com/middleware-labs/agent-apm-go-chi-legacy"
7)
8
9func main() {
10  r := chi.NewRouter()
11  config, _ := track.Track(
12    track.WithConfigTag("service","<apm-service>"),
13    track.WithConfigTag("accessToken","<MW_API_KEY>"),
14  )
15  r.Use(mwchi.Middleware("<my-server>", mwchi.WithChiRoutes(r)))
16}

1go get github.com/middleware-labs/agent-apm-go-chi@latest
2
3import (
4  "github.com/go-chi/chi/v5"
5  track "github.com/middleware-labs/golang-apm/tracker"
6  mwchi "github.com/middleware-labs/agent-apm-go-chi"
7)

1go get github.com/middleware-labs/golang-apm-beego@latest
2
3import (
4  track "github.com/middleware-labs/golang-apm/tracker"
5  mwbeego "github.com/middleware-labs/golang-apm-beego/beego"
6)

1go get github.com/middleware-labs/golang-apm-sql@latest
2
3import (
4  track "github.com/middleware-labs/golang-apm/tracker"
5  mwsql "github.com/middleware-labs/golang-apm-sql/sql"
6)
7db, err := mwsql.Open("mysql", "user:pass@tcp(127.0.0.1:3306)/dbname")

1go get github.com/middleware-labs/golang-apm-mongo@latest
2
3import (
4  "go.mongodb.org/mongo-driver/mongo/options"
5  track "github.com/middleware-labs/golang-apm/tracker"
6  mwmongo "github.com/middleware-labs/golang-apm-mongo/mongo"
7)
8opts := options.Client()
9opts.Monitor = mwmongo.NewMonitor()

1go get github.com/middleware-labs/golang-apm-grpc@latest
2
3import (
4  "google.golang.org/grpc"
5  mwgrpc "github.com/middleware-labs/golang-apm-grpc/grpc"
6  track "github.com/middleware-labs/golang-apm/tracker"
7)
8
9server := grpc.NewServer(
10  grpc.UnaryInterceptor(mwgrpc.UnaryServerInterceptor()),
11  grpc.StreamInterceptor(mwgrpc.StreamServerInterceptor()),
12)

5. Sending custom data

A. Custom logs (choose your logger)

All adapters below forward structured logs to Middleware with active trace/span context.

• log/slog:
  Your API Keys

  1import (
  2    "log/slog"
  3    "github.com/middleware-labs/golang-apm/mwotelslog"
  4    track "github.com/middleware-labs/golang-apm/tracker"
  5    )
  6
  7    config, _ := track.Track(
  8    track.WithConfigTag(track.Service, "svc"),
  9    track.WithConfigTag(track.Token,   "<MW_API_KEY>"),
  10    )
  11
  12    logger := mwotelslog.NewMWOTelLogger(config,
  13    mwotelslog.WithDefaultConsoleLog(),
  14    mwotelslog.WithName("otelslog"),
  15    )
  16    slog.SetDefault(logger)

• Zap:
  Your API Keys

  1import (
  2        "go.uber.org/zap"
  3        "go.uber.org/zap/zapcore"
  4        mwotelzap "github.com/middleware-labs/golang-apm/mwotelzap"
  5        track "github.com/middleware-labs/golang-apm/tracker"
  6    )
  7
  8    config, _ := track.Track(
  9        track.WithConfigTag(track.Service, "svc"),
  10        track.WithConfigTag(track.Token,   "<MW_API_KEY>"),
  11    )
  12
  13    logger := zap.New(zapcore.NewTee(/* consoleCore, fileCore, */ mwotelzap.NewMWOTelCore(config, mwotelzap.WithName("otelzaplog"))))
  14    zap.ReplaceGlobals(logger)

• zerolog

1import (
2  "github.com/rs/zerolog/log"
3  mwotelzerolog "github.com/middleware-labs/golang-apm/mwotelzerolog"
4  track "github.com/middleware-labs/golang-apm/tracker"
5)
6
7config, _ := track.Track(
8  track.WithConfigTag(track.Service, "svc"),
9  track.WithConfigTag(track.Token,   "<MW_API_KEY>"),
10)
11hook := mwotelzerolog.NewMWOTelHook(config)
12logger := log.Hook(hook)

• logrus

1import (
2  log "github.com/sirupsen/logrus"
3  otellog "github.com/middleware-labs/golang-apm/mwotellogrus"
4  track "github.com/middleware-labs/golang-apm/tracker"
5)
6
7config, _ := track.Track(
8  track.WithConfigTag(track.Service, "svc"),
9  track.WithConfigTag(track.Token,   "<MW_API_KEY>"),
10)
11logHook := otellog.NewMWOTelHook(config, otellog.WithLevels(log.AllLevels), otellog.WithName("otellogrus"))
12log.AddHook(logHook)
13log.SetFormatter(&log.JSONFormatter{})

B. Record errors (stack traces)

1err := errors.New("something went wrong")
2track.ErrorRecording(ctx, err)

C. Get current span

1span := track.SpanFromContext(ctx)

D. Custom spans, events & attributes (quick taste)

1config, _ := track.Track(
2  track.WithConfigTag("service", "<APM-SERVICE-NAME>"),
3  track.WithConfigTag("accessToken", "<MW_API_KEY>"),
4)
5tp := config.Tp
6
7ctx, span := tp.Tracer("example-tracer").Start(ctx, "example-span")
8span.AddEvent("starting work")
9track.SetAttribute(ctx, "user.id", "123")
10defer span.End()

6. Continuous profiling

Profiling starts automatically once the tracker is configured (Step 2). Use the Continuous Profiling section in the app to explore CPU, memory, goroutines, etc.

7. Telemetry & debug options

• Pause default runtime metrics only

  1track.WithConfigTag(track.PauseDefaultMetrics, true)

• Pause metrics / traces / logs / profiling

  1track.WithConfigTag(track.PauseMetrics|PauseTraces|PauseLogs|PauseProfiling, true)

  (You can also use the matching MW_APM_COLLECT_* env vars below.)
• Debug to console

  1track.WithConfigTag(track.Debug, true)

• Debug to files

  1track.WithConfigTag(track.Debug, true) + track.WithConfigTag(track.DebugLogFile, true)

8. Environment variables (quick reference)

9. View your data

After a short delay, you’ll see telemetry in the Middleware app:

• APM: service overview, traces, errors
• Logs: any logs forwarded via adapters above
• Continuous Profiling: CPU/mem/goroutine flamegraphs

See “Viewing Data” for where these live in the UI.10. Troubleshooting

• No data from containers/K8s → verify MW_AGENT_SERVICE (Docker bridge gateway is often 172.17.0.1; use the K8s service DNS shown above).
• High local noise → enable Debug to see what’s emitted (track.Debug, track.DebugLogFile).
• Too much overhead → pause what you don’t need (PauseMetrics/DefaultMetrics/Traces/Logs/Profiling or the env vars).