Merge branch 'main' of gitea.libretechconsulting.com:rmcguire/go-app

TODO.md

@@ -1,14 +1,15 @@
 # TODO
 
+- [ ] Add ability to initialize OTEL early (before app runs)
 - [ ] Spruce up the README
-- [ ] Create generic interface for implenting a service
+- [ ] Create generic interface for implementing a service
 - [ ] Create config sample not called demo, so it is more easily reused
 - [ ] Expand config test case to cover GRPC config
 - [ ] Expand tracing
 
 ## Done
 
-- [x] Test and troubleshoot GRPC Gateway supprot
+- [x] Test and troubleshoot GRPC Gateway support
 - [x] Finish implementing GRPC service support
 - [x] Unit tests
 - [x] Pattern for extending config

pkg/app/app_types.go

@@ -1,3 +1,5 @@
+// Package app provides methods to configure, run, and stop
+// a go-app.
 package app
 
 import (
@@ -11,6 +13,8 @@ import (
 	httpopts "gitea.libretechconsulting.com/rmcguire/go-app/pkg/srv/http/opts"
 )
 
+// App is the main application struct, holding its context, configurations,
+// and various services like HTTP and gRPC.
 type App struct {
 	AppContext    context.Context
 	HTTP          *httpopts.AppHTTP

pkg/app/init.go

@@ -62,7 +62,12 @@ func (a *App) initHTTP(ctx context.Context) error {
 	return err
 }
 
-func (a *App) initOTEL() {
+func (a *App) InitOTEL() {
+	if a.tracer != nil {
+		a.l.Debug().Msg("superfluous call of already configured app otel")
+		return
+	}
+
 	var otelShutdown shutdownFunc
 	a.AppContext, otelShutdown = otel.Init(a.AppContext)
 	a.shutdownFuncs = append(a.shutdownFuncs, otelShutdown)

pkg/app/monitor.go

@@ -27,7 +27,7 @@ func (a *App) monitor() {
 	a.appDone <- nil // Notify app
 }
 
-// Typically invoked when AppContext is done
+// Shutdown is typically invoked when AppContext is done
 // or Server has exited. Not intended to be called
 // manually
 func (a *App) Shutdown() {

pkg/app/run.go

@@ -35,7 +35,7 @@ func (a *App) MustRun() {
 
 	// Start OTEL
 	// Registers a NO-OP provider if not enabled
-	a.initOTEL()
+	a.InitOTEL()
 
 	// With OTEL ready, create an init span to track startup
 	ctx, initSpan := a.tracer.Start(a.AppContext, "init")

pkg/app/schema.go

@@ -6,11 +6,11 @@ import (
 	js "github.com/swaggest/jsonschema-go"
 )
 
-// Generates json schema for app's config.AppConfig
+// Schema generates json schema for app's config.AppConfig
-func (app *App) Schema() ([]byte, error) {
+func (a *App) Schema() ([]byte, error) {
 	r := js.Reflector{}
 
-	s, err := r.Reflect(*app.cfg)
+	s, err := r.Reflect(*a.cfg)
 	if err != nil {
 		return nil, err
 	}
@@ -18,7 +18,7 @@ func (app *App) Schema() ([]byte, error) {
 	return json.MarshalIndent(s, "", "  ")
 }
 
-// Generates json schema for custom config
+// CustomSchema generates json schema for custom config
 // which embeds *config.AppConfig into it
 // Panics if no *config.AppConfig is embedded into custom
 // config type

pkg/app/setup.go

@@ -9,7 +9,7 @@ import (
 	"gitea.libretechconsulting.com/rmcguire/go-app/pkg/logging"
 )
 
-// Helper function to return a context loaded up with
+// MustSetupConfigAndLogging is a helper function to return a context loaded up with
 // config.AppConfig and a logger
 func MustSetupConfigAndLogging(ctx context.Context) context.Context {
 	ctx, err := config.LoadConfig(ctx)
@@ -24,7 +24,7 @@ func MustSetupConfigAndLogging(ctx context.Context) context.Context {
 	return ctx
 }
 
-// Unmarshal config into a custom type
+// MustSetupConfigAndLoggingInto will unmarshal config into a custom type
 // Type MUST include *config.AppConfig
 // Stored in context as *config.AppConfig but can be asserted back
 func MustSetupConfigAndLoggingInto[T any](ctx context.Context, into T) (context.Context, T) {

pkg/app/setup_custom.go

@@ -13,7 +13,7 @@ import (
 	"gitea.libretechconsulting.com/rmcguire/go-app/pkg/config"
 )
 
-// Used to unmarshal config and environment into a custom type
+// MustLoadConfigInto is used to unmarshal config and environment into a custom type
 // that overloads *config.AppConfig. Will perform normal env
 // substitutions for AppConfig, but env overrides for custom type
 // are up to the caller.

pkg/config/config.go

@@ -17,15 +17,15 @@ import (
 	"gopkg.in/yaml.v3"
 )
 
-// To be set by ldflags in go build command or
+// Version is to be set by ldflags in go build command or
-// retrieved from build meta below
+// retrieved from build meta below.
 var Version = "(devel)"
 
-// Calling this will try to load from config if -config is
+// LoadConfig will try to load from config if -config is
 // provided as a file, and will apply any environment overrides
 // on-top of configuration defaults.
 // Config is stored in returned context, and can be retrieved
-// using config.FromCtx(ctx)
+// using config.FromCtx(ctx).
 func LoadConfig(ctx context.Context) (context.Context, error) {
 	configPath := flag.String("config", "", "Path to the configuration file")
 	flag.Parse()
@@ -44,6 +44,8 @@ func LoadConfig(ctx context.Context) (context.Context, error) {
 	return ctx, nil
 }
 
+// loadConfig loads the application configuration from the specified path,
+// applying environment variable overrides.
 func loadConfig(configPath string) (*AppConfig, error) {
 	cfg := *DefaultConfig
 
@@ -73,6 +75,8 @@ func loadConfig(configPath string) (*AppConfig, error) {
 	return &cfg, nil
 }
 
+// prepareConfig enriches and validates the AppConfig, parsing duration strings
+// for HTTP timeouts.
 func prepareConfig(cfg *AppConfig) error {
 	var errs error
 
@@ -104,12 +108,14 @@ func prepareConfig(cfg *AppConfig) error {
 	return errs
 }
 
-// Returns read timeout, write timeout, and idle timeout, in that order
+// Timeouts returns read timeout, write timeout, and idle timeout, in that order.
-// nil if unset
+// Returns nil if unset.
 func (h *HTTPConfig) Timeouts() (*time.Duration, *time.Duration, *time.Duration) {
 	return h.rT, h.wT, h.iT
 }
 
+// getVersion returns the application version, preferring the build info version
+// over the compile-time set Version variable.
 func getVersion() string {
 	if info, ok := debug.ReadBuildInfo(); ok && info.Main.Version != "(devel)" {
 		return info.Main.Version

pkg/config/ctx.go

@@ -9,10 +9,12 @@ type appConfigKey uint8
 
 const appConfigCtxKey appConfigKey = iota
 
-func (a *AppConfig) AddToCtx(ctx context.Context) context.Context {
+// AddToCtx adds the AppConfig to the provided context.
-	return context.WithValue(ctx, appConfigCtxKey, a)
+func (ac *AppConfig) AddToCtx(ctx context.Context) context.Context {
+	return context.WithValue(ctx, appConfigCtxKey, ac)
 }
 
+// MustFromCtx retrieves the AppConfig from the context, or panics if not found.
 func MustFromCtx(ctx context.Context) *AppConfig {
 	cfg, err := FromCtx(ctx)
 	if err != nil {
@@ -21,6 +23,7 @@ func MustFromCtx(ctx context.Context) *AppConfig {
 	return cfg
 }
 
+// FromCtx retrieves the AppConfig from the context.
 func FromCtx(ctx context.Context) (*AppConfig, error) {
 	ctxData := ctx.Value(appConfigCtxKey)
 	if ctxData == nil {

pkg/config/types.go

@@ -1,6 +1,6 @@
 package config
 
-// Default Settings
+// DefaultConfig provides a default application configuration.
 var DefaultConfig = &AppConfig{
 	Environment: "development",
 	Version:     getVersion(),
@@ -23,6 +23,7 @@ type AppConfig struct {
 	GRPC    *GRPCConfig `yaml:"grpc,omitempty" json:"grpc,omitempty"`
 }
 
+// HTTPEnabled returns true if HTTP is enabled in the AppConfig.
 func (ac *AppConfig) HTTPEnabled() bool {
 	if ac.HTTP != nil && ac.HTTP.Enabled {
 		return true
@@ -30,6 +31,7 @@ func (ac *AppConfig) HTTPEnabled() bool {
 	return false
 }
 
+// GRPCEnabled returns true if gRPC is enabled in the AppConfig.
 func (ac *AppConfig) GRPCEnabled() bool {
 	if ac.GRPC != nil && ac.GRPC.Enabled {
 		return true
@@ -37,6 +39,7 @@ func (ac *AppConfig) GRPCEnabled() bool {
 	return false
 }
 
+// OTELEnabled returns true if OpenTelemetry is enabled in the AppConfig.
 func (ac *AppConfig) OTELEnabled() bool {
 	if ac.OTEL != nil && ac.OTEL.Enabled {
 		return true

pkg/config/types_http.go

@@ -12,7 +12,7 @@ var defaultHTTPConfig = &HTTPConfig{
 	IdleTimeout:  "1m",
 }
 
-// HTTP Configuration
+// HTTPConfig provides HTTP server Configuration
 type HTTPConfig struct {
 	Enabled      bool   `yaml:"enabled" env:"APP_HTTP_ENABLED" json:"enabled,omitempty"`
 	Listen       string `yaml:"listen,omitempty" env:"APP_HTTP_LISTEN" json:"listen,omitempty"`

pkg/config/types_logging.go

@@ -8,7 +8,7 @@ var defaultLoggingConfig = &LogConfig{
 	TimeFormat: TimeFormatLong,
 }
 
-// Logging Configuration
+// LogConfig provides Logging Configuration
 type LogConfig struct {
 	Enabled    bool       `yaml:"enabled,omitempty" env:"APP_LOG_ENABLED" json:"enabled,omitempty"`
 	Level      string     `yaml:"level,omitempty" env:"APP_LOG_LEVEL" json:"level,omitempty"`

pkg/config/types_otel.go

@@ -8,7 +8,7 @@ var defaultOTELConfig = &OTELConfig{
 	MetricIntervalSecs: 30,
 }
 
-// OTEL Configuration
+// OtelConfig provides OTEL Configuration
 type OTELConfig struct {
 	Enabled            bool   `yaml:"enabled,omitempty" env:"APP_OTEL_ENABLED" json:"enabled,omitempty"`
 	PrometheusEnabled  bool   `yaml:"prometheusEnabled,omitempty" env:"APP_OTEL_PROMETHEUS_ENABLED" json:"prometheusEnabled,omitempty"`

pkg/logging/logging.go

@@ -1,3 +1,5 @@
+// Package logging provides a centralized logging utility using zerolog,
+// with configurable output formats and log levels.
 package logging
 
 import (

pkg/otel/otel.go

@@ -1,3 +1,4 @@
+// Package otel provides OpenTelemetry initialization and configuration for tracing and metrics.
 package otel
 
 import (
@@ -39,6 +40,7 @@ var (
 
 const defMetricInterval = 15 * time.Second
 
+// Init prepares otel, loading a tracer and meter stored in appp context.
 // Context must carry config.AppConfig
 func Init(ctx context.Context) (context.Context, func(context.Context) error) {
 	cfg := config.MustFromCtx(ctx)
@@ -232,7 +234,7 @@ func (s *settings) newMeterProvider(ctx context.Context) (*metric.MeterProvider,
 	return meterProvider, nil
 }
 
-// Creates a new tracer from the global opentelemetry provider
+// NewTracer creates a new tracer from the global opentelemetry provider
 func NewTracer(options ...trace.TracerOption) trace.Tracer {
 	return opentelemetry.GetTracerProvider().Tracer(
 		os.Getenv("OTEL_SERVICE_NAME"),

pkg/srv/grpc/grpc.go

@@ -1,3 +1,5 @@
+// Package grpc provides a gRPC server implementation with OpenTelemetry integration
+// and gRPC Gateway for RESTful API exposure.
 package grpc
 
 import (