config: separate schema version support into separate directories

CHANGELOG.md

@@ -19,6 +19,7 @@ This project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.htm
 
 - Change the span name to be `GET /path` so it complies with the OTel HTTP semantic conventions in `go.opentelemetry.io/contrib/instrumentation/github.com/labstack/echo/otelecho`. (#6365)
 - Record errors instead of setting the `gin.errors` attribute in `go.opentelemetry.io/contrib/instrumentation/github.com/gin-gonic/gin/otelgin`. (#6346)
+- The `go.opentelemetry.io/contrib/config` now supports multiple schemas in subdirectories (ie. `go.opentelemetry.io/contrib/config/v0.3.0`) for easier migration. (#6412)
 
 ### Fixed
 

Makefile

@@ -325,11 +325,12 @@ OPENTELEMETRY_CONFIGURATION_JSONSCHEMA_VERSION=v0.3.0
 genjsonschema-cleanup:
 	rm -Rf ${OPENTELEMETRY_CONFIGURATION_JSONSCHEMA_SRC_DIR}
 
-GENERATED_CONFIG=./config/generated_config.go
+GENERATED_CONFIG=./config/${OPENTELEMETRY_CONFIGURATION_JSONSCHEMA_VERSION}/generated_config.go
 
 # Generate structs for configuration from opentelemetry-configuration schema
 genjsonschema: genjsonschema-cleanup $(GOJSONSCHEMA)
 	mkdir -p ${OPENTELEMETRY_CONFIGURATION_JSONSCHEMA_SRC_DIR}
+	mkdir -p ./config/${OPENTELEMETRY_CONFIGURATION_JSONSCHEMA_VERSION}
 	curl -sSL https://api.github.com/repos/open-telemetry/opentelemetry-configuration/tarball/${OPENTELEMETRY_CONFIGURATION_JSONSCHEMA_VERSION} | tar xz --strip 1 -C ${OPENTELEMETRY_CONFIGURATION_JSONSCHEMA_SRC_DIR}
 	$(GOJSONSCHEMA) \
 		--capitalization ID \

config/doc.go

@@ -1,7 +1,10 @@
 // Copyright The OpenTelemetry Authors
 // SPDX-License-Identifier: Apache-2.0
 
-// Package config can be used to parse a configuration file
-// that follows the JSON Schema defined by the OpenTelemetry
-// Configuration schema.
+// Package config can be used to parse a configuration file that follows
+// the JSON Schema defined by the OpenTelemetry Configuration schema. Different
+// versions of the schema are supported by the code in the directory that
+// matches the version number of the schema. For example, the import
+// go.opentelemetry.io/contrib/config/v0.3.0 includes code that supports the
+// v0.3.0 release of the configuration schema.
 package config // import "go.opentelemetry.io/contrib/config"

config/v0.2.0/config.go

@@ -0,0 +1,152 @@
+// Copyright The OpenTelemetry Authors
+// SPDX-License-Identifier: Apache-2.0
+
+package config // import "go.opentelemetry.io/contrib/config/v0.2.0"
+
+import (
+	"context"
+	"errors"
+
+	"gopkg.in/yaml.v3"
+
+	"go.opentelemetry.io/otel/log"
+	nooplog "go.opentelemetry.io/otel/log/noop"
+	"go.opentelemetry.io/otel/metric"
+	noopmetric "go.opentelemetry.io/otel/metric/noop"
+	"go.opentelemetry.io/otel/trace"
+	nooptrace "go.opentelemetry.io/otel/trace/noop"
+)
+
+const (
+	protocolProtobufHTTP = "http/protobuf"
+	protocolProtobufGRPC = "grpc/protobuf"
+
+	compressionGzip = "gzip"
+	compressionNone = "none"
+)
+
+type configOptions struct {
+	ctx                 context.Context
+	opentelemetryConfig OpenTelemetryConfiguration
+}
+
+type shutdownFunc func(context.Context) error
+
+func noopShutdown(context.Context) error {
+	return nil
+}
+
+// SDK is a struct that contains all the providers
+// configured via the configuration model.
+type SDK struct {
+	meterProvider  metric.MeterProvider
+	tracerProvider trace.TracerProvider
+	loggerProvider log.LoggerProvider
+	shutdown       shutdownFunc
+}
+
+// TracerProvider returns a configured trace.TracerProvider.
+func (s *SDK) TracerProvider() trace.TracerProvider {
+	return s.tracerProvider
+}
+
+// MeterProvider returns a configured metric.MeterProvider.
+func (s *SDK) MeterProvider() metric.MeterProvider {
+	return s.meterProvider
+}
+
+// LoggerProvider returns a configured log.LoggerProvider.
+func (s *SDK) LoggerProvider() log.LoggerProvider {
+	return s.loggerProvider
+}
+
+// Shutdown calls shutdown on all configured providers.
+func (s *SDK) Shutdown(ctx context.Context) error {
+	return s.shutdown(ctx)
+}
+
+var noopSDK = SDK{
+	loggerProvider: nooplog.LoggerProvider{},
+	meterProvider:  noopmetric.MeterProvider{},
+	tracerProvider: nooptrace.TracerProvider{},
+	shutdown:       func(ctx context.Context) error { return nil },
+}
+
+// NewSDK creates SDK providers based on the configuration model.
+func NewSDK(opts ...ConfigurationOption) (SDK, error) {
+	o := configOptions{}
+	for _, opt := range opts {
+		o = opt.apply(o)
+	}
+	if o.opentelemetryConfig.Disabled != nil && *o.opentelemetryConfig.Disabled {
+		return noopSDK, nil
+	}
+
+	r, err := newResource(o.opentelemetryConfig.Resource)
+	if err != nil {
+		return noopSDK, err
+	}
+
+	mp, mpShutdown, err := meterProvider(o, r)
+	if err != nil {
+		return noopSDK, err
+	}
+
+	tp, tpShutdown, err := tracerProvider(o, r)
+	if err != nil {
+		return noopSDK, err
+	}
+
+	lp, lpShutdown, err := loggerProvider(o, r)
+	if err != nil {
+		return noopSDK, err
+	}
+
+	return SDK{
+		meterProvider:  mp,
+		tracerProvider: tp,
+		loggerProvider: lp,
+		shutdown: func(ctx context.Context) error {
+			return errors.Join(mpShutdown(ctx), tpShutdown(ctx), lpShutdown(ctx))
+		},
+	}, nil
+}
+
+// ConfigurationOption configures options for providers.
+type ConfigurationOption interface {
+	apply(configOptions) configOptions
+}
+
+type configurationOptionFunc func(configOptions) configOptions
+
+func (fn configurationOptionFunc) apply(cfg configOptions) configOptions {
+	return fn(cfg)
+}
+
+// WithContext sets the context.Context for the SDK.
+func WithContext(ctx context.Context) ConfigurationOption {
+	return configurationOptionFunc(func(c configOptions) configOptions {
+		c.ctx = ctx
+		return c
+	})
+}
+
+// WithOpenTelemetryConfiguration sets the OpenTelemetryConfiguration used
+// to produce the SDK.
+func WithOpenTelemetryConfiguration(cfg OpenTelemetryConfiguration) ConfigurationOption {
+	return configurationOptionFunc(func(c configOptions) configOptions {
+		c.opentelemetryConfig = cfg
+		return c
+	})
+}
+
+// ParseYAML parses a YAML configuration file into an OpenTelemetryConfiguration.
+func ParseYAML(file []byte) (*OpenTelemetryConfiguration, error) {
+	var cfg OpenTelemetryConfiguration
+	err := yaml.Unmarshal(file, &cfg)
+	if err != nil {
+		return nil, err
+	}
+
+	return &cfg, nil
+}