feat: automatically generate context ignore paths

gen/docs/gen_env.go

@@ -0,0 +1,133 @@
+package main
+
+import (
+	"bytes"
+	"errors"
+	"fmt"
+	"io/fs"
+	"log/slog"
+	"os"
+	"reflect"
+	"strings"
+
+	"github.com/tinyauthapp/tinyauth/internal/model"
+)
+
+type EnvEntry struct {
+	Name        string
+	Description string
+	Value       any
+}
+
+func generateExampleEnv() {
+	cfg := model.NewDefaultConfiguration()
+	entries := make([]EnvEntry, 0)
+
+	root := reflect.TypeOf(cfg).Elem()
+	rootValue := reflect.ValueOf(cfg).Elem()
+	rootPath := "TINYAUTH_"
+
+	walkAndBuild(root, rootValue, rootPath, &entries, buildEnvEntry, buildEnvMapEntry, buildEnvChildPath)
+	compiled := compileEnv(entries)
+
+	err := os.Remove(".env.example")
+	if err != nil && !errors.Is(err, fs.ErrNotExist) {
+		slog.Error("failed to remove example env file", "error", err)
+		os.Exit(1)
+	}
+
+	err = os.WriteFile(".env.example", compiled, 0644)
+	if err != nil {
+		slog.Error("failed to write example env file", "error", err)
+		os.Exit(1)
+	}
+}
+
+func buildEnvEntry(child reflect.StructField, childValue reflect.Value, parentPath string, entries *[]EnvEntry) {
+	desc := child.Tag.Get("description")
+	tag := child.Tag.Get("yaml")
+
+	if tag == "-" {
+		return
+	}
+
+	value := childValue.Interface()
+
+	entry := EnvEntry{
+		Name:        parentPath + strings.ToUpper(child.Name),
+		Description: desc,
+	}
+
+	switch childValue.Kind() {
+	case reflect.Slice:
+		sl, ok := value.([]string)
+		if !ok {
+			slog.Error("invalid default value", "value", value)
+			return
+		}
+		entry.Value = strings.Join(sl, ",")
+	case reflect.String:
+		st, ok := value.(string)
+		if !ok {
+			slog.Error("invalid default value", "value", value)
+			return
+		}
+		if st != "" {
+			entry.Value = fmt.Sprintf(`"%s"`, st)
+		} else {
+			entry.Value = ""
+		}
+	default:
+		entry.Value = value
+	}
+	*entries = append(*entries, entry)
+}
+
+func buildEnvMapEntry(child reflect.StructField, parentPath string, entries *[]EnvEntry) {
+	fieldType := child.Type
+
+	if fieldType.Key().Kind() != reflect.String {
+		slog.Info("unsupported map key type", "type", fieldType.Key().Kind())
+		return
+	}
+
+	mapPath := parentPath + strings.ToUpper(child.Name) + "_name_"
+	valueType := fieldType.Elem()
+
+	if valueType.Kind() == reflect.Struct {
+		zeroValue := reflect.New(valueType).Elem()
+		walkAndBuild(valueType, zeroValue, mapPath, entries, buildEnvEntry, buildEnvMapEntry, buildEnvChildPath)
+	}
+}
+
+func buildEnvChildPath(parent string, child string) string {
+	return parent + strings.ToUpper(child) + "_"
+}
+
+func compileEnv(entries []EnvEntry) []byte {
+	buffer := bytes.Buffer{}
+
+	buffer.WriteString("# This file is automatically generated by gen/gen_env.go. Do not edit manually.\n\n")
+	buffer.WriteString("# Tinyauth example configuration\n\n")
+
+	previousSection := ""
+
+	for _, entry := range entries {
+		if strings.Count(entry.Name, "_") > 1 {
+			section := strings.Split(strings.TrimPrefix(entry.Name, "TINYAUTH_"), "_")[0]
+			if section != previousSection {
+				buffer.WriteString("\n# " + strings.ToLower(section) + " config\n\n")
+				previousSection = section
+			}
+		}
+		buffer.WriteString("# ")
+		buffer.WriteString(entry.Description)
+		buffer.WriteString("\n")
+		buffer.WriteString(entry.Name)
+		buffer.WriteString("=")
+		fmt.Fprintf(&buffer, "%v", entry.Value)
+		buffer.WriteString("\n")
+	}
+
+	return buffer.Bytes()
+}