OpAMP load/save effective configuration using remote_configuration_directory

CHANGELOG.md

@@ -33,6 +33,14 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 [#1279]: https://github.com/SumoLogic/sumologic-otel-collector/pull/1279
 [v0.87.0-sumo-0]: https://github.com/SumoLogic/sumologic-otel-collector/compare/v0.86.0-sumo-0...v0.87.0-sumo-0
 
+### Changed
+
+- feat(opampextension): opamp effective configuration is only derived from the
+  remote_configuration_directory contents and the contents are managed by the
+  extension [#1274]
+
+[#1274]: https://github.com/SumoLogic/sumologic-otel-collector/pull/1274
+
 ## [v0.86.0-sumo-0]
 
 ### Released 2023-10-04

pkg/extension/opampextension/README.md

@@ -40,9 +40,8 @@ extensions:
     installation_token: <token>
     api_base_url: <api_endpoint_url>
   opamp:
-    instance_uid: <uniq_uid>
     endpoint: <wss_endpoint_url>
-    remote_configuration_directory: /etc/otelcol-sumo/conf.d
+    remote_configuration_directory: /etc/otelcol-sumo/opamp.d
 ```
 
 ## API URLs
@@ -68,7 +67,7 @@ option:
 
 Here is a list of valid values for the OpAMP `endpoint** configuration option:
 
-**Note:** As of Jan 2023, these endpoints are not yet available.
+**Note:** These endpoints are not yet available.
 
 |  Deployment   | API base URL                                |
 |:-------------:|---------------------------------------------|
@@ -84,11 +83,8 @@ Here is a list of valid values for the OpAMP `endpoint** configuration option:
 ## Storing local configuration
 
 When the OpAMP extension receives a remote configuration from the OpAMP server,
-it persists the YAML configuration to a local file. The path of this file is
-determined by the `remote_configuration_directory` configuration option and the
-file name is `opamp-remote-config.yaml`. For example, if
-`remote_configuration_directory` is set to `/etc/otelcol-sumo/conf.d`, the
-resulting local configuration file path would be
-`/etc/otelcol-sumo/conf.d/opamp-remote-config.yaml`. A configuration provider
-must be used in order to load the stored configuration, for example: `--config
-"glob:/etc/otelcol-sumo/conf.d/*"`.
+it persists each received YAML configuration to a local file in the
+`remote_configuration_directory`. The existing contents of the
+`remote_configuration_directory` are removed before doing so. A configuration
+provider must be used in order to load the stored configuration, for example:
+`--config "glob:/etc/otelcol-sumo/opamp.d/*"`.

pkg/extension/opampextension/config.go

@@ -16,6 +16,8 @@ package opampextension
 
 import (
 	"errors"
+	"fmt"
+	"os"
 
 	"github.com/oklog/ulid/v2"
 	"go.opentelemetry.io/collector/component"
@@ -34,6 +36,9 @@ type Config struct {
 	// RemoteConfigurationDirectory is where received OpAMP remote configuration
 	// is stored.
 	RemoteConfigurationDirectory string `mapstructure:"remote_configuration_directory"`
+
+	// AcceptsRemoteConfiguration indicates if the OpAMP agent will accept remote configuration.
+	AcceptsRemoteConfiguration bool `mapstructure:"accepts_remote_configuration"`
 }
 
 // CreateDefaultHTTPClientSettings returns default http client settings
@@ -58,5 +63,10 @@ func (cfg *Config) Validate() error {
 		return errors.New("opamp remote_configuration_directory must be provided")
 	}
 
+	d := cfg.RemoteConfigurationDirectory
+	if _, err := os.Stat(d); err != nil {
+		return fmt.Errorf("opamp remote_configuration_directory %s must be readable: %v", d, err)
+	}
+
 	return nil
 }

pkg/extension/opampextension/config_test.go

@@ -15,7 +15,9 @@
 package opampextension
 
 import (
+	"os"
 	"path/filepath"
+	"strings"
 	"testing"
 
 	"github.com/stretchr/testify/assert"
@@ -50,7 +52,8 @@ func TestUnmarshalConfig(t *testing.T) {
 				},
 			},
 			InstanceUID:                  "01BX5ZZKBKACTAV9WEVGEMMVRZ",
-			RemoteConfigurationDirectory: "/tmp/",
+			RemoteConfigurationDirectory: "/tmp/opamp.d",
+			AcceptsRemoteConfiguration:   true,
 		}, cfg)
 }
 
@@ -59,9 +62,19 @@ func TestConfigValidate(t *testing.T) {
 	err := cfg.Validate()
 	require.Error(t, err)
 	assert.Equal(t, "opamp remote_configuration_directory must be provided", err.Error())
-	cfg.RemoteConfigurationDirectory = "/tmp/"
+
+	cfg.RemoteConfigurationDirectory = "/tmp/opamp.d"
 	err = cfg.Validate()
-	require.NoError(t, err)
+	assert.True(t, strings.HasPrefix(err.Error(), "opamp remote_configuration_directory /tmp/opamp.d must be readable:"))
+
+	d, err := os.MkdirTemp("", "opamp.d")
+	assert.NoError(t, err)
+	defer os.RemoveAll(d)
+
+	cfg.RemoteConfigurationDirectory = d
+	err = cfg.Validate()
+	assert.NoError(t, err)
+
 	cfg.InstanceUID = "01BX5ZZKBKACTAV9WEVGEMMVRZFAIL"
 	err = cfg.Validate()
 	require.Error(t, err)

pkg/extension/opampextension/factory.go

@@ -32,7 +32,8 @@ func NewFactory() extension.Factory {
 
 func createDefaultConfig() component.Config {
 	return &Config{
-		HTTPClientSettings: CreateDefaultHTTPClientSettings(),
+		HTTPClientSettings:         CreateDefaultHTTPClientSettings(),
+		AcceptsRemoteConfiguration: true,
 	}
 }
 

pkg/extension/opampextension/factory_test.go

@@ -37,6 +37,7 @@ func TestFactory_CreateDefaultConfig(t *testing.T) {
 				AuthenticatorID: component.NewID("sumologic"),
 			},
 		},
+		AcceptsRemoteConfiguration: true,
 	})
 
 	assert.NoError(t, componenttest.CheckConfigStruct(cfg))

pkg/extension/opampextension/go.mod

@@ -4,6 +4,7 @@ go 1.20
 
 require (
 	github.com/SumoLogic/sumologic-otel-collector/pkg/extension/sumologicextension v0.77.0-sumo-0
+	github.com/google/uuid v1.3.0
 	github.com/knadh/koanf/parsers/yaml v0.1.0
 	github.com/knadh/koanf/providers/rawbytes v0.1.0
 	github.com/knadh/koanf/v2 v2.0.1

pkg/extension/opampextension/go.sum

@@ -27,6 +27,8 @@ github.com/google/go-cmp v0.5.5/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/
 github.com/google/go-cmp v0.5.6/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
 github.com/google/go-cmp v0.5.9 h1:O2Tfq5qg4qc4AmwVlvv0oLiVAGB7enBSJ2x2DqQFi38=
 github.com/google/go-cmp v0.5.9/go.mod h1:17dUlkBOakJ0+DkrSSNjCkIjxS6bF9zb3elmeNGIjoY=
+github.com/google/uuid v1.3.0 h1:t6JiXgmwXMjEs8VusXIJk2BXHsn+wx8BZdTaoZ5fu7I=
+github.com/google/uuid v1.3.0/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
 github.com/gorilla/websocket v1.4.2 h1:+/TMaTYc4QFitKJxsQ7Yye35DkWvkdLcvGKqM+x0Ufc=
 github.com/gorilla/websocket v1.4.2/go.mod h1:YR8l580nyteQvAITg2hZ9XVh4b55+EU/adAjf1fMHhE=
 github.com/hashicorp/errwrap v1.0.0 h1:hLrqtEDnRye3+sgx6z4qVLNuviH3MR5aQ0ykNJa/UYA=