fix: update newHandlerFn to take a logger to canonicalize logging for…

… system integration

examples/complex/handler.go

@@ -4,7 +4,6 @@ import (
 	"context"
 	"log/slog"
 	"net/http"
-	"os"
 
 	fdk "github.com/CrowdStrike/foundry-fn-go"
 )
@@ -17,8 +16,7 @@ func (c config) OK() error {
 	return nil
 }
 
-func newHandler(ctx context.Context, cfg config) fdk.Handler {
-	logger := slog.New(slog.NewJSONHandler(os.Stdout, &slog.HandlerOptions{AddSource: true}))
+func newHandler(_ context.Context, logger *slog.Logger, cfg config) fdk.Handler {
 	mux := fdk.NewMux()
 
 	h := handler{

examples/fn_config/main.go

@@ -4,6 +4,7 @@ import (
 	"context"
 	"encoding/json"
 	"errors"
+	"log/slog"
 	"net/http"
 
 	fdk "github.com/CrowdStrike/foundry-fn-go"
@@ -16,7 +17,7 @@ func main() {
 // newHandler here is showing how a config is integrated. It is using generics,
 // so we can unmarshal the config into a concrete type and then validate it. The
 // OK method is run to validate the contents of the config.
-func newHandler(_ context.Context, cfg config) fdk.Handler {
+func newHandler(context.Context, *slog.Logger, config) fdk.Handler {
 	mux := fdk.NewMux()
 	mux.Get("/foo", fdk.HandlerFn(func(ctx context.Context, r fdk.Request) fdk.Response {
 		return fdk.Response{

examples/fn_no_config/main.go

@@ -3,6 +3,7 @@ package main
 import (
 	"context"
 	"encoding/json"
+	"log/slog"
 	"net/http"
 
 	fdk "github.com/CrowdStrike/foundry-fn-go"
@@ -15,7 +16,7 @@ func main() {
 // newHandlerWithCfg here is showcasing a handler that does not utilize a config, so
 // it provides the SkipCfg as the config so no config load is attempted. This is the
 // minority of functions.
-func newHandler(context.Context, fdk.SkipCfg) fdk.Handler {
+func newHandler(context.Context, *slog.Logger, fdk.SkipCfg) fdk.Handler {
 	mux := fdk.NewMux()
 	mux.Get("/", fdk.HandlerFn(func(ctx context.Context, r fdk.Request) fdk.Response {
 		return fdk.Response{

runner.go

@@ -8,9 +8,7 @@ import (
 )
 
 // Runner defines the runtime that executes the request/response handler lifecycle.
-type Runner interface {
-	Run(ctx context.Context, logger *slog.Logger, h Handler)
-}
+type Runner func(ctx context.Context, newHandlerFn func(context.Context, *slog.Logger) Handler)
 
 // RegisterRunner registers a runner.
 func RegisterRunner(runnerType string, r Runner) {
@@ -21,7 +19,7 @@ func RegisterRunner(runnerType string, r Runner) {
 	runners[runnerType] = r
 }
 
-func run(ctx context.Context, logger *slog.Logger, h Handler) {
+func run(ctx context.Context, newHandlerFn func(context.Context, *slog.Logger) Handler) {
 	rt := os.Getenv("CS_RUNNER_TYPE")
 	if rt == "" {
 		rt = "http"
@@ -32,9 +30,9 @@ func run(ctx context.Context, logger *slog.Logger, h Handler) {
 		panic(fmt.Sprintf("invalid RUNNER_TYPE provided: %q", rt))
 	}
 
-	r.Run(ctx, logger, h)
+	r(ctx, newHandlerFn)
 }
 
-var runners = map[string]Runner{
-	"http": new(runnerHTTP),
+var runners = map[string]func(ctx context.Context, newHandlerFn func(context.Context, *slog.Logger) Handler){
+	"http": runHTTP,
 }

runner_http.go

@@ -24,11 +24,40 @@ const (
 	mb = 1 << 20
 )
 
-type runnerHTTP struct{}
+func runHTTP(ctx context.Context, newHandlerFn func(context.Context, *slog.Logger) Handler) {
+	logger := slog.New(slog.NewJSONHandler(os.Stdout, &slog.HandlerOptions{AddSource: true}))
+
+	handler := newHandlerFn(ctx, logger)
 
-func (r *runnerHTTP) Run(ctx context.Context, logger *slog.Logger, h Handler) {
 	mux := http.NewServeMux()
-	mux.Handle("/", http.HandlerFunc(func(w http.ResponseWriter, req *http.Request) {
+	mux.Handle("/", dispatchReq(logger, handler))
+
+	s := &http.Server{
+		Addr:           fmt.Sprintf(":%d", port()),
+		Handler:        mux,
+		MaxHeaderBytes: mb,
+	}
+	go func() {
+		select {
+		case <-ctx.Done():
+			shutdownCtx, cancel := context.WithTimeout(context.Background(), 15*time.Second)
+			defer cancel()
+
+			logger.Info("shutting down HTTP server...")
+			if err := s.Shutdown(shutdownCtx); err != nil {
+				logger.Error("failed to shutdown server", "err", err)
+			}
+		}
+	}()
+
+	logger.Info("serving HTTP server on port " + strconv.Itoa(port()))
+	if err := s.ListenAndServe(); err != nil && !errors.Is(err, http.ErrServerClosed) {
+		logger.Error("unexpected shutdown of server", "err", err)
+	}
+}
+
+func dispatchReq(logger *slog.Logger, handler Handler) http.Handler {
+	return http.HandlerFunc(func(w http.ResponseWriter, req *http.Request) {
 		defer func() {
 			if n, err := io.Copy(io.Discard, req.Body); err != nil {
 				logger.Error("failed to drain request body", "err", err.Error(), "bytes_drained", n)
@@ -54,9 +83,9 @@ func (r *runnerHTTP) Run(ctx context.Context, logger *slog.Logger, h Handler) {
 		}()
 
 		const ctxKeyTraceID = "_traceid"
-		ctx = context.WithValue(ctx, ctxKeyTraceID, r.TraceID)
+		ctx := context.WithValue(req.Context(), ctxKeyTraceID, r.TraceID)
 
-		resp := h.Handle(ctx, r)
+		resp := handler.Handle(ctx, r)
 
 		if f, ok := resp.Body.(File); ok {
 			f = NormalizeFile(f)
@@ -94,30 +123,7 @@ func (r *runnerHTTP) Run(ctx context.Context, logger *slog.Logger, h Handler) {
 		if err != nil {
 			logger.Error("failed to write response", "err", err)
 		}
-	}))
-
-	s := &http.Server{
-		Addr:           fmt.Sprintf(":%d", port()),
-		Handler:        mux,
-		MaxHeaderBytes: mb,
-	}
-	go func() {
-		select {
-		case <-ctx.Done():
-			shutdownCtx, cancel := context.WithTimeout(context.Background(), 15*time.Second)
-			defer cancel()
-
-			logger.Info("shutting down HTTP server...")
-			if err := s.Shutdown(shutdownCtx); err != nil {
-				logger.Error("failed to shutdown server", "err", err)
-			}
-		}
-	}()
-
-	logger.Info("serving HTTP server on port " + strconv.Itoa(port()))
-	if err := s.ListenAndServe(); err != nil && !errors.Is(err, http.ErrServerClosed) {
-		logger.Error("unexpected shutdown of server", "err", err)
-	}
+	})
 }
 
 func toRequest(req *http.Request) (Request, func() error, error) {

runner_test.go

@@ -7,6 +7,7 @@ import (
 	"encoding/json"
 	"errors"
 	"io"
+	"log/slog"
 	"net"
 	"net/http"
 	"net/url"
@@ -567,7 +568,7 @@ integer: 1`,
 				ctx, cancel := context.WithCancel(context.Background())
 				defer cancel()
 
-				addr := newServer(ctx, t, func(ctx context.Context, cfg config) fdk.Handler {
+				addr := newServer(ctx, t, func(ctx context.Context, _ *slog.Logger, cfg config) fdk.Handler {
 					return tt.newHandlerFn(ctx, cfg)
 				})
 
@@ -720,7 +721,7 @@ integer: 1`,
 				ctx, cancel := context.WithCancel(context.Background())
 				defer cancel()
 
-				addr := newServer(ctx, t, func(ctx context.Context, cfg config) fdk.Handler {
+				addr := newServer(ctx, t, func(ctx context.Context, _ *slog.Logger, cfg config) fdk.Handler {
 					return tt.newHandlerFn(ctx, cfg)
 				})
 
@@ -840,7 +841,7 @@ integer: 1`,
 				ctx, cancel := context.WithCancel(context.Background())
 				defer cancel()
 
-				addr := newServer(ctx, t, func(ctx context.Context, cfg fdk.SkipCfg) fdk.Handler {
+				addr := newServer(ctx, t, func(ctx context.Context, _ *slog.Logger, cfg fdk.SkipCfg) fdk.Handler {
 					return tt.newHandlerFn(ctx, cfg)
 				})
 
@@ -1006,7 +1007,7 @@ integer: 1`,
 				ctx, cancel := context.WithCancel(context.Background())
 				defer cancel()
 
-				addr := newServer(ctx, t, func(ctx context.Context, _ fdk.SkipCfg) fdk.Handler {
+				addr := newServer(ctx, t, func(ctx context.Context, _ *slog.Logger, _ fdk.SkipCfg) fdk.Handler {
 					return tt.newHandlerFn(ctx)
 				})
 
@@ -1250,7 +1251,7 @@ func decodeJSON(t testing.TB, b []byte, v any) {
 	}
 }
 
-func newServer[CFG fdk.Cfg](ctx context.Context, t *testing.T, newHandlerFn func(context.Context, CFG) fdk.Handler) string {
+func newServer[CFG fdk.Cfg](ctx context.Context, t *testing.T, newHandlerFn func(context.Context, *slog.Logger, CFG) fdk.Handler) string {
 	t.Helper()
 
 	port := newIP(t)
@@ -1261,8 +1262,8 @@ func newServer[CFG fdk.Cfg](ctx context.Context, t *testing.T, newHandlerFn func
 	done := make(chan struct{})
 	go func() {
 		defer close(done)
-		fdk.Run(ctx, func(ctx context.Context, cfg CFG) fdk.Handler {
-			h := newHandlerFn(ctx, cfg)
+		fdk.Run(ctx, func(ctx context.Context, logger *slog.Logger, cfg CFG) fdk.Handler {
+			h := newHandlerFn(ctx, logger, cfg)
 			close(readyChan)
 			return h
 		})

sdk.go

@@ -4,7 +4,6 @@ import (
 	"context"
 	"log/slog"
 	"net/http"
-	"os"
 	"runtime/debug"
 )
 
@@ -14,25 +13,25 @@ type Handler interface {
 }
 
 // Run is the meat and potatoes. This is the entrypoint for everything.
-func Run[T Cfg](ctx context.Context, newHandlerFn func(_ context.Context, cfg T) Handler) {
-	logger := slog.New(slog.NewJSONHandler(os.Stdout, &slog.HandlerOptions{AddSource: true}))
-
-	var runFn Handler = HandlerFn(func(ctx context.Context, r Request) Response {
-		cfg, loadErr := readCfg[T](ctx)
-		if loadErr != nil {
-			if loadErr.err != nil {
-				logger.Error("failed to load config", "err", loadErr.err)
+func Run[T Cfg](ctx context.Context, newHandlerFn func(context.Context, *slog.Logger, T) Handler) {
+	run(ctx, func(ctx context.Context, logger *slog.Logger) Handler {
+		var runFn Handler = HandlerFn(func(ctx context.Context, r Request) Response {
+			cfg, loadErr := readCfg[T](ctx)
+			if loadErr != nil {
+				if loadErr.err != nil {
+					logger.Error("failed to load config", "err", loadErr.err)
+				}
+				return ErrResp(loadErr.apiErr)
 			}
-			return ErrResp(loadErr.apiErr)
-		}
 
-		h := newHandlerFn(ctx, cfg)
+			h := newHandlerFn(ctx, logger, cfg)
 
-		return h.Handle(ctx, r)
-	})
-	runFn = recoverer(logger)(runFn)
+			return h.Handle(ctx, r)
+		})
+		runFn = recoverer(logger)(runFn)
 
-	run(ctx, logger, runFn)
+		return runFn
+	})
 }
 
 func recoverer(logger *slog.Logger) func(Handler) Handler {