Allow passing confmap.Providers to the Collector

.chloggen/pass-confmap-providers.yaml

@@ -0,0 +1,25 @@
+# Use this changelog template to create an entry for release notes.
+
+# One of 'breaking', 'deprecation', 'new_component', 'enhancement', 'bug_fix'
+change_type: enhancement
+
+# The name of the component, or a single word describing the area of concern, (e.g. otlpreceiver)
+component: otelcol
+
+# A brief description of the change.  Surround your text with quotes ("") if it needs to start with a backtick (`).
+note: Add `ConfigProviderSettings` to `CollectorSettings`
+
+# One or more tracking issues or pull requests related to the change
+issues: [4759]
+
+# (Optional) One or more lines of additional information to render under the primary note.
+# These lines will be padded with 2 spaces and then inserted directly into the document.
+# Use pipe (|) for multiline entries.
+subtext: This allows passing a custom list of `confmap.Provider`s to `otelcol.NewCommand`.
+
+# Optional: The change log or logs in which this entry should be included.
+# e.g. '[user]' or '[user, api]'
+# Include 'user' if the change is relevant to end users.
+# Include 'api' if there is a change to a library API.
+# Default: '[user]'
+change_logs: []

otelcol/collector.go

@@ -7,7 +7,6 @@ package otelcol // import "go.opentelemetry.io/collector/otelcol"
 
 import (
 	"context"
-	"errors"
 	"fmt"
 	"os"
 	"os/signal"
@@ -66,10 +65,16 @@ type CollectorSettings struct {
 	// and manually handle the signals to shutdown the collector.
 	DisableGracefulShutdown bool
 
+	// Deprecated: [v0.93.0] Use ConfigProviderSettings instead.
 	// ConfigProvider provides the service configuration.
 	// If the provider watches for configuration change, collector may reload the new configuration upon changes.
 	ConfigProvider ConfigProvider
 
+	// ConfigProviderSettings allows configuring the way the Collector retrieves its configuration
+	// The Collector will reload based on configuration changes from the ConfigProvider if any
+	// confmap.Providers watch for configuration changes.
+	ConfigProviderSettings ConfigProviderSettings
+
 	// LoggingOptions provides a way to change behavior of zap logging.
 	LoggingOptions []zap.Option
 
@@ -92,6 +97,8 @@ type CollectorSettings struct {
 type Collector struct {
 	set CollectorSettings
 
+	configProvider ConfigProvider
+
 	service *service.Service
 	state   *atomic.Int32
 
@@ -105,8 +112,20 @@ type Collector struct {
 
 // NewCollector creates and returns a new instance of Collector.
 func NewCollector(set CollectorSettings) (*Collector, error) {
-	if set.ConfigProvider == nil {
-		return nil, errors.New("invalid nil config provider")
+	var err error
+	configProvider := set.ConfigProvider
+
+	if configProvider == nil {
+		resolverSet := set.ConfigProviderSettings.ResolverSettings
+		// Provide a default set of providers and converters if none have been specified.
+		if len(resolverSet.Providers) == 0 && len(resolverSet.Converters) == 0 {
+			set.ConfigProviderSettings = newDefaultConfigProviderSettings(resolverSet.URIs)
+		}
+
+		configProvider, err = NewConfigProvider(set.ConfigProviderSettings)
+		if err != nil {
+			return nil, err
+		}
 	}
 
 	state := &atomic.Int32{}
@@ -119,6 +138,7 @@ func NewCollector(set CollectorSettings) (*Collector, error) {
 		// the number of signals getting notified on is recommended.
 		signalsChannel:    make(chan os.Signal, 3),
 		asyncErrorChannel: make(chan error),
+		configProvider:    configProvider,
 	}, nil
 }
 
@@ -146,7 +166,7 @@ func (col *Collector) setupConfigurationComponents(ctx context.Context) error {
 
 	var conf *confmap.Conf
 
-	if cp, ok := col.set.ConfigProvider.(ConfmapProvider); ok {
+	if cp, ok := col.configProvider.(ConfmapProvider); ok {
 		var err error
 		conf, err = cp.GetConfmap(ctx)
 
@@ -159,7 +179,7 @@ func (col *Collector) setupConfigurationComponents(ctx context.Context) error {
 	if err != nil {
 		return fmt.Errorf("failed to initialize factories: %w", err)
 	}
-	cfg, err := col.set.ConfigProvider.Get(ctx, factories)
+	cfg, err := col.configProvider.Get(ctx, factories)
 	if err != nil {
 		return fmt.Errorf("failed to get config: %w", err)
 	}
@@ -215,7 +235,7 @@ func (col *Collector) DryRun(ctx context.Context) error {
 	if err != nil {
 		return fmt.Errorf("failed to initialize factories: %w", err)
 	}
-	cfg, err := col.set.ConfigProvider.Get(ctx, factories)
+	cfg, err := col.configProvider.Get(ctx, factories)
 	if err != nil {
 		return fmt.Errorf("failed to get config: %w", err)
 	}
@@ -243,7 +263,7 @@ func (col *Collector) Run(ctx context.Context) error {
 LOOP:
 	for {
 		select {
-		case err := <-col.set.ConfigProvider.Watch():
+		case err := <-col.configProvider.Watch():
 			if err != nil {
 				col.service.Logger().Error("Config watch failed", zap.Error(err))
 				break LOOP
@@ -280,7 +300,7 @@ func (col *Collector) shutdown(ctx context.Context) error {
 	// Accumulate errors and proceed with shutting down remaining components.
 	var errs error
 
-	if err := col.set.ConfigProvider.Shutdown(ctx); err != nil {
+	if err := col.configProvider.Shutdown(ctx); err != nil {
 		errs = multierr.Append(errs, fmt.Errorf("failed to shutdown config provider: %w", err))
 	}