update deps to 0.42.0 and provide double dollar config source parsing compatibility

CHANGELOG.md

@@ -2,9 +2,15 @@
 
 ## Unreleased
 
+This Splunk OpenTelemetry Collector release includes changes from the [opentelemetry-collector v0.42.0](https://github.com/open-telemetry/opentelemetry-collector/releases/tag/v0.42.0) and the [opentelemetry-collector-contrib v0.42.0](https://github.com/open-telemetry/opentelemetry-collector-contrib/releases/tag/v0.42.0) releases.
+
+### 🛑 Breaking changes 🛑
+
+- This version adopts OpenTelemetry Core version 0.42.0, and in doing so the configuration parsing process has changed slightly. The Splunk OpenTelemetry Collector used to [evaluate user configuration twice](https://github.com/signalfx/splunk-otel-collector/issues/628) and this required escaping desired `$` literals with an additional `$` character to prevent unwanted environment variable expansion. This version no longer doubly evaluates configuration so any `$$` instances in your configuration as a workaround should be updated to `$`.  [Config source directives](./internal/configsource) that include an additional `$` are provided with a temporary, backward-compatible `$${config_source:value}` and `$$config_source:value` parsing rule controlled by `SPLUNK_DOUBLE_DOLLAR_CONFIG_SOURCE_COMPATIBLE` environment variable (default `"true"`) to migrate them to single `$` usage to continue supporting the updating configs from [#930](https://github.com/signalfx/splunk-otel-collector/pull/930) and [#935](https://github.com/signalfx/splunk-otel-collector/pull/935). This functionality will be removed in a future release (#1099)
+
 ### 🚀 New components 🚀
 
-- [`docker_observer`](https://github.com/open-telemetry/opentelemetry-collector-contrib/tree/main/extension/observer/dockerobserver) to detect and create container endpoints, to be used with the [`receiver_creator`](https://github.com/open-telemetry/opentelemetry-collector-contrib/tree/main/receiver/receivercreator).
+- [`docker_observer`](https://github.com/open-telemetry/opentelemetry-collector-contrib/tree/main/extension/observer/dockerobserver) to detect and create container endpoints, to be used with the [`receiver_creator`](https://github.com/open-telemetry/opentelemetry-collector-contrib/tree/main/receiver/receivercreator) (#1044)
 
 ## v0.41.0
 

cmd/otelcol/main.go

@@ -18,7 +18,6 @@
 package main
 
 import (
-	"bytes"
 	"flag"
 	"fmt"
 	"io"
@@ -29,6 +28,7 @@ import (
 
 	"go.opentelemetry.io/collector/component"
 	"go.opentelemetry.io/collector/config/configmapprovider"
+	"go.opentelemetry.io/collector/config/configunmarshaler"
 	"go.opentelemetry.io/collector/service"
 	"go.uber.org/zap"
 
@@ -82,31 +82,38 @@ func main() {
 		Version: version.Version,
 	}
 
-	parserProvider := configprovider.NewConfigSourceParserProvider(
-		newBaseParserProvider(),
+	configMapProviderFromConfigSources := configprovider.NewConfigSourceConfigMapProvider(
+		baseConfigMapProviders(),
 		zap.NewNop(), // The service logger is not available yet, setting it to NoP.
 		info,
 		configsources.Get()...,
 	)
 
+	var configMapConverters []service.ConfigMapConverterFunc
+
 	const noConvertConfigFlag = "--no-convert-config"
 	if hasFlag(noConvertConfigFlag) {
 		// the collector complains about this flag if we don't remove it
 		removeFlag(&os.Args, noConvertConfigFlag)
 	} else {
-		parserProvider = configconverter.ParserProvider(
-			parserProvider,
+		configMapConverters = append(configMapConverters,
 			configconverter.RemoveBallastKey,
 			configconverter.MoveOTLPInsecureKey,
 			configconverter.MoveHecTLS,
 			configconverter.RenameK8sTagger,
 		)
 	}
 
+	serviceConfigProvider := service.NewConfigProvider(
+		[]configmapprovider.Provider{configMapProviderFromConfigSources},
+		configMapConverters,
+		configunmarshaler.NewDefault(),
+	)
+
 	serviceParams := service.CollectorSettings{
-		BuildInfo:         info,
-		Factories:         factories,
-		ConfigMapProvider: parserProvider,
+		BuildInfo:      info,
+		Factories:      factories,
+		ConfigProvider: serviceConfigProvider,
 	}
 
 	if err := run(serviceParams); err != nil {
@@ -370,8 +377,8 @@ func setDefaultEnvVars() {
 	}
 }
 
-// Returns a ParserProvider that reads configuration YAML from an environment variable when applicable.
-func newBaseParserProvider() configmapprovider.Provider {
+// Returns a []configmapprovider.Provider for reading from yaml env var or config path and set properties
+func baseConfigMapProviders() []configmapprovider.Provider {
 	var configPath string
 	var ok bool
 	if ok, configPath = getKeyValue(os.Args[1:], "--config"); !ok {
@@ -380,10 +387,13 @@ func newBaseParserProvider() configmapprovider.Provider {
 	configYaml := os.Getenv(configYamlEnvVarName)
 
 	if configPath == "" && configYaml != "" {
-		return configmapprovider.NewExpand(configmapprovider.NewInMemory(bytes.NewBufferString(configYaml)))
+		return []configmapprovider.Provider{configmapprovider.NewEnv(configYamlEnvVarName)}
 	}
 
-	return configmapprovider.NewDefault(configPath, getSetProperties())
+	return []configmapprovider.Provider{
+		configmapprovider.NewFile(configPath),
+		configmapprovider.NewProperties(getSetProperties()),
+	}
 }
 
 func runInteractive(settings service.CollectorSettings) error {