v0.22.0 several enhancements and fixes for security, network, doc, test, packaging

internal/config/loader.go

@@ -18,8 +18,11 @@ var ErrConfigNotFound = lconfig.ErrConfigNotFound
 // Manager owns the configuration sources and watcher for one application instance.
 // Its snapshots are detached from each other and from the running service.
 type Manager struct {
-	config *lconfig.Config
-	path   string
+	config   *lconfig.Config
+	path     string
+	explicit bool
+	read     bool           // the file was loaded once
+	specs    []pipelineSpec // command-line or environment pipelines, kept across reloads
 }
 
 // Load reads the startup sources and validates the initial configuration.
@@ -29,13 +32,30 @@ func Load(args []string) (*Manager, error) {
 	if err != nil {
 		return nil, err
 	}
+	specs, configArgs, err := takePipelineSpecs(configArgs)
+	if err != nil {
+		return nil, err
+	}
+	if len(specs) == 0 {
+		specs = envPipelineSpecs()
+	}
+	if _, err := buildPipelines(specs); err != nil {
+		return nil, err
+	}
+	m := &Manager{path: configPath, explicit: isExplicit, specs: specs}
 	initial := defaults()
 	cfg, err := lconfig.NewBuilder().
 		WithTarget(initial).
 		WithEnvPrefix("LOGWISP_").
 		WithArgs(configArgs).
 		WithFile(configPath).
-		WithTypedValidator(ValidateConfig).
+		WithTypedValidator(func(cfg *Config) error {
+			effective := *cfg // the builder keeps cfg; only the copy is replaced
+			if err := m.usePipelines(&effective); err != nil {
+				return err
+			}
+			return ValidateConfig(&effective)
+		}).
 		WithSecurityOptions(lconfig.SecurityOptions{
 			PreventPathTraversal: true,
 			MaxFileSize:          10 * 1024 * 1024,
@@ -50,10 +70,12 @@ func Load(args []string) (*Manager, error) {
 		}
 		// A missing discovered default still permits valid CLI/env/default values.
 	}
+	m.read = err == nil
 	if unknown := cfg.UnknownCLIKeys(); len(unknown) > 0 && !initial.Quiet {
 		fmt.Fprintf(os.Stderr, "Warning: unrecognized flags ignored: %v\n", unknown)
 	}
-	return &Manager{config: cfg, path: configPath}, nil
+	m.config = cfg
+	return m, nil
 }
 
 // Snapshot validates a detached candidate before it is used to build a service.
@@ -65,6 +87,9 @@ func (m *Manager) Snapshot() (*Config, error) {
 	}
 	cfg := value.(*Config)
 	cfg.ConfigFile = m.path
+	if err := m.usePipelines(cfg); err != nil {
+		return nil, err
+	}
 	if err := checkFileKeys(m.path); err != nil {
 		return nil, fmt.Errorf("config file %q: %w", m.path, err)
 	}
@@ -74,12 +99,27 @@ func (m *Manager) Snapshot() (*Config, error) {
 	return cfg, nil
 }
 
+// usePipelines replaces the file's or default pipelines with the spec ones.
+func (m *Manager) usePipelines(cfg *Config) error {
+	if len(m.specs) == 0 {
+		return nil
+	}
+	pipelines, err := buildPipelines(m.specs)
+	cfg.Pipelines = pipelines
+	return err
+}
+
 // Reload rereads the selected file, retaining the startup CLI/environment sources.
 // Signals must call this even when automatic watching is disabled.
 func (m *Manager) Reload() (*Config, error) {
-	if err := m.config.LoadFile(m.path); err != nil {
+	// As at startup, a discovered default that does not exist is no error, so a
+	// file-less instance still rebuilds and rotates its certificates. Once read,
+	// its removal is one: the loader would keep the removed file's values.
+	err := m.config.LoadFile(m.path)
+	if err != nil && (m.explicit || m.read || !errors.Is(err, ErrConfigNotFound)) {
 		return nil, fmt.Errorf("reload %q: %w", m.path, err)
 	}
+	m.read = m.read || err == nil
 	return m.Snapshot()
 }