feat(httplog): add http logger for debugging

cmd/httplog/go.mod

@@ -0,0 +1,14 @@
+module github.com/therootcompany/golib/cmd/httplog
+
+go 1.24.6
+
+require (
+	github.com/fatih/color v1.18.0
+	github.com/therootcompany/golib/colorjson v1.0.0
+)
+
+require (
+	github.com/mattn/go-colorable v0.1.13 // indirect
+	github.com/mattn/go-isatty v0.0.20 // indirect
+	golang.org/x/sys v0.25.0 // indirect
+)

cmd/httplog/go.sum

@@ -0,0 +1,13 @@
+github.com/fatih/color v1.18.0 h1:S8gINlzdQ840/4pfAwic/ZE0djQEH3wM94VfqLTZcOM=
+github.com/fatih/color v1.18.0/go.mod h1:4FelSpRwEGDpQ12mAdzqdOukCy4u8WUtOY6lkT/6HfU=
+github.com/mattn/go-colorable v0.1.13 h1:fFA4WZxdEF4tXPZVKMLwD8oUnCTTo08duU7wxecdEvA=
+github.com/mattn/go-colorable v0.1.13/go.mod h1:7S9/ev0klgBDR4GtXTXX8a3vIGJpMovkB8vQcUbaXHg=
+github.com/mattn/go-isatty v0.0.16/go.mod h1:kYGgaQfpe5nmfYZH+SKPsOc2e4SrIfOl2e/yFXSvRLM=
+github.com/mattn/go-isatty v0.0.20 h1:xfD0iDuEKnDkl03q4limB+vH+GxLEtL/jb4xVJSWWEY=
+github.com/mattn/go-isatty v0.0.20/go.mod h1:W+V8PltTTMOvKvAeJH7IuucS94S2C6jfK/D7dTCTo3Y=
+github.com/therootcompany/golib/colorjson v1.0.0 h1:ihsmHrY9mRrClO94KSx4ed3bql1eaLnzOT+1QEnWlug=
+github.com/therootcompany/golib/colorjson v1.0.0/go.mod h1:bE0wCyOsRFQnz22+TnQu4D0+FPl+ZugaaE79bjgDqRw=
+golang.org/x/sys v0.0.0-20220811171246-fbc7d0a398ab/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.6.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.25.0 h1:r+8e+loiHxRqhXVl6ML1nO3l1+oFoWbnlu2Ehimmi34=
+golang.org/x/sys v0.25.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=

cmd/httplog/main.go

@@ -0,0 +1,102 @@
+package main
+
+import (
+	"encoding/json"
+	"fmt"
+	"io"
+	"log"
+	"net/http"
+	"os"
+	"strings"
+
+	"github.com/fatih/color"
+	"github.com/therootcompany/golib/colorjson"
+)
+
+var jsonf = colorjson.NewFormatter()
+
+func main() {
+	jsonf.Indent = 3
+	color.NoColor = false // TODO manual override via flags
+
+	mux := http.NewServeMux()
+	mux.HandleFunc("GET /", handler)
+	mux.HandleFunc("POST /", handler)
+	mux.HandleFunc("PATCH /", handler)
+	mux.HandleFunc("PUT /", handler)
+	mux.HandleFunc("DELETE /", handler)
+
+	addr := "localhost:8088"
+	fmt.Printf("Listening on %s...\n\n", addr)
+	log.Fatal(http.ListenAndServe(addr, mux))
+}
+
+func handler(w http.ResponseWriter, r *http.Request) {
+	// Log method, path, and query
+	var query string
+	if len(r.URL.RawQuery) > 0 {
+		query = "?" + r.URL.RawQuery
+	}
+	log.Printf("%s %s%s", r.Method, r.URL.Path, query)
+
+	// Find max header name length for alignment
+	maxLen := len("HOST")
+	for name := range r.Header {
+		if len(name) > maxLen {
+			maxLen = len(name)
+		}
+	}
+	maxLen += 1
+
+	fmt.Printf("   %-"+fmt.Sprintf("%d", maxLen+1)+"s %s\n", "HOST", r.Host)
+	for name, values := range r.Header {
+		for _, value := range values {
+			fmt.Printf("   %-"+fmt.Sprintf("%d", maxLen+1)+"s %s\n", name+":", value)
+		}
+	}
+	fmt.Fprintf(os.Stderr, "\n")
+
+	body, err := io.ReadAll(r.Body)
+	switch strings.ToUpper(r.Method) {
+	case "GET", "DELETE":
+		if len(body) > 0 {
+			fmt.Fprintf(os.Stderr, "Unexpected body:\n%q\n", string(body))
+		}
+		return
+	case "POST", "PATCH", "PUT":
+		break
+	default:
+		fmt.Fprintf(os.Stderr, "Unexpected method\n")
+		return
+	}
+	defer fmt.Println()
+
+	// Read request body
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "Failed to read body:\n%q\n", string(body))
+		return
+	}
+	defer func() {
+		_ = r.Body.Close()
+	}()
+
+	// Parse and pretty-print JSON, or raw body
+	var text string
+	var data any
+	if err := json.Unmarshal(body, &data); err == nil {
+		body, _ = jsonf.Marshal(data)
+	}
+
+	text = string(body)
+	text = prefixLines(text, "   ")
+	text = strings.TrimSpace(text)
+	fmt.Printf("   %s\n", text)
+}
+
+func prefixLines(text, prefix string) string {
+	lines := strings.Split(text, "\n")
+	for i, line := range lines {
+		lines[i] = prefix + line
+	}
+	return strings.Join(lines, "\n")
+}