[extension/storage/redis_storage] Add a new Redis extension to store data in transit (#33224)

**Description:**
Add a new extension allowing to store data in transit in a Redis
cluster.

**Link to tracking Issue:**
Fixes #31682

**Testing:**
Unit tests

**Documentation:**
README

---------

Co-authored-by: Evan Bradley <[email protected]>
Co-authored-by: Curtis Robert <[email protected]>

Author: 3 people

.chloggen/redis-storage.yaml

@@ -0,0 +1,27 @@
+# Use this changelog template to create an entry for release notes.
+
+# One of 'breaking', 'deprecation', 'new_component', 'enhancement', 'bug_fix'
+change_type: new_component
+
+# The name of the component, or a single word describing the area of concern, (e.g. filelogreceiver)
+component: redis_storage
+
+# A brief description of the change.  Surround your text with quotes ("") if it needs to start with a backtick (`).
+note: Adds a new storage extension using Redis to store data in transit
+
+# Mandatory: One or more tracking issues related to the change. You can use the PR number here if no issue exists.
+issues: [31682]
+
+# (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:
+
+# If your change doesn't affect end users or the exported elements of any package,
+# you should instead start your pull request title with [chore] or use the "Skip Changelog" label.
+# 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: []

.github/CODEOWNERS

@@ -119,6 +119,7 @@ extension/solarwindsapmsettingsextension/                           @open-teleme
 extension/storage/                                                  @open-telemetry/collector-contrib-approvers @dmitryax @atoulme @djaglowski
 extension/storage/dbstorage/                                        @open-telemetry/collector-contrib-approvers @dmitryax @atoulme
 extension/storage/filestorage/                                      @open-telemetry/collector-contrib-approvers @djaglowski
+extension/storage/redisstorageextension/                            @open-telemetry/collector-contrib-approvers @atoulme
 extension/sumologicextension/                                       @open-telemetry/collector-contrib-approvers @aboguszewski-sumo @kkujawa-sumo @mat-rumian @rnishtala-sumo @sumo-drosiek
 
 internal/aws/                                                       @open-telemetry/collector-contrib-approvers @Aneurysm9 @mxiamxia

.github/ISSUE_TEMPLATE/bug_report.yaml

@@ -117,6 +117,7 @@ body:
       - extension/storage
       - extension/storage/dbstorage
       - extension/storage/filestorage
+      - extension/storage/redisstorage
       - extension/sumologic
       - internal/aws
       - internal/collectd

.github/ISSUE_TEMPLATE/feature_request.yaml

@@ -111,6 +111,7 @@ body:
       - extension/storage
       - extension/storage/dbstorage
       - extension/storage/filestorage
+      - extension/storage/redisstorage
       - extension/sumologic
       - internal/aws
       - internal/collectd

.github/ISSUE_TEMPLATE/other.yaml

@@ -111,6 +111,7 @@ body:
       - extension/storage
       - extension/storage/dbstorage
       - extension/storage/filestorage
+      - extension/storage/redisstorage
       - extension/sumologic
       - internal/aws
       - internal/collectd

.github/ISSUE_TEMPLATE/unmaintained.yaml

@@ -116,6 +116,7 @@ body:
       - extension/storage
       - extension/storage/dbstorage
       - extension/storage/filestorage
+      - extension/storage/redisstorage
       - extension/sumologic
       - internal/aws
       - internal/collectd

extension/storage/redisstorageextension/Makefile

@@ -0,0 +1 @@
+include ../../../Makefile.Common

extension/storage/redisstorageextension/README.md

@@ -0,0 +1,48 @@
+# File Storage
+
+<!-- status autogenerated section -->
+| Status        |           |
+| ------------- |-----------|
+| Stability     | [development]  |
+| Distributions | [] |
+| Issues        | [![Open issues](https://img.shields.io/github/issues-search/open-telemetry/opentelemetry-collector-contrib?query=is%3Aissue%20is%3Aopen%20label%3Aextension%2Fredisstorage%20&label=open&color=orange&logo=opentelemetry)](https://github.com/open-telemetry/opentelemetry-collector-contrib/issues?q=is%3Aopen+is%3Aissue+label%3Aextension%2Fredisstorage) [![Closed issues](https://img.shields.io/github/issues-search/open-telemetry/opentelemetry-collector-contrib?query=is%3Aissue%20is%3Aclosed%20label%3Aextension%2Fredisstorage%20&label=closed&color=blue&logo=opentelemetry)](https://github.com/open-telemetry/opentelemetry-collector-contrib/issues?q=is%3Aclosed+is%3Aissue+label%3Aextension%2Fredisstorage) |
+| [Code Owners](https://github.com/open-telemetry/opentelemetry-collector-contrib/blob/main/CONTRIBUTING.md#becoming-a-code-owner)    | [@atoulme](https://www.github.com/atoulme) \| Seeking more code owners! |
+
+[development]: https://github.com/open-telemetry/opentelemetry-collector#development
+<!-- end autogenerated section -->
+
+The Redis Storage extension can persist state to a Redis cluster.
+
+The extension requires read and write access to a Redis cluster.
+
+## Config
+- `endpoint` (required): The endpoint of the redis instance to connect to. Default: `localhost:6379`
+- `password` (optional): the password to connect to the redis instance. Default: ``
+- `db` (optional): Database to be selected after connecting to the server. Default: 0
+- `expiration` (optional): TTL for all storage entries. Default TTL means the key has no expiration time. Default: 0
+
+## Example
+
+```
+extensions:
+  redis_storage:
+  redis_storage/all_settings:
+    endpoint: localhost:6379
+    password: ""
+    db: 0
+    expiration: 5m
+
+service:
+  extensions: [redis_storage, redis_storage/all_settings]
+  pipelines:
+    traces:
+      receivers: [nop]
+      processors: [nop]
+      exporters: [nop]
+
+# Data pipeline is required to load the config.
+receivers:
+  nop:
+exporters:
+  nop:
+```

extension/storage/redisstorageextension/config.go

@@ -0,0 +1,18 @@
+// Copyright The OpenTelemetry Authors
+// SPDX-License-Identifier: Apache-2.0
+
+package redisstorageextension // import "github.com/open-telemetry/opentelemetry-collector-contrib/extension/storage/redisstorageextension"
+
+import (
+	"time"
+
+	"go.opentelemetry.io/collector/config/configopaque"
+)
+
+// Config defines configuration for the Redis storage extension.
+type Config struct {
+	Endpoint   string              `mapstructure:"endpoint"`
+	Password   configopaque.String `mapstructure:"password"`
+	DB         int                 `mapstructure:"db"`
+	Expiration time.Duration       `mapstructure:"expiration"`
+}

extension/storage/redisstorageextension/config_test.go

@@ -0,0 +1,58 @@
+// Copyright The OpenTelemetry Authors
+// SPDX-License-Identifier: Apache-2.0
+
+package redisstorageextension
+
+import (
+	"path/filepath"
+	"testing"
+	"time"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+	"go.opentelemetry.io/collector/component"
+	"go.opentelemetry.io/collector/confmap/confmaptest"
+
+	"github.com/open-telemetry/opentelemetry-collector-contrib/extension/storage/redisstorageextension/internal/metadata"
+)
+
+func TestLoadConfig(t *testing.T) {
+	t.Parallel()
+
+	tests := []struct {
+		id       component.ID
+		expected component.Config
+	}{
+		{
+			id: component.NewID(metadata.Type),
+			expected: func() component.Config {
+				ret := NewFactory().CreateDefaultConfig()
+				ret.(*Config).Endpoint = "localhost:1234"
+				return ret
+			}(),
+		},
+		{
+			id: component.NewIDWithName(metadata.Type, "all_settings"),
+			expected: &Config{
+				Endpoint:   "localhost:1234",
+				Password:   "passwd",
+				DB:         1,
+				Expiration: 3 * time.Hour,
+			},
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.id.String(), func(t *testing.T) {
+			cm, err := confmaptest.LoadConf(filepath.Join("testdata", "config.yaml"))
+			require.NoError(t, err)
+			factory := NewFactory()
+			cfg := factory.CreateDefaultConfig()
+			sub, err := cm.Sub(tt.id.String())
+			require.NoError(t, err)
+			require.NoError(t, sub.Unmarshal(&cfg))
+
+			assert.NoError(t, component.ValidateConfig(cfg))
+			assert.Equal(t, tt.expected, cfg)
+		})
+	}
+}

extension/storage/redisstorageextension/doc.go

@@ -0,0 +1,5 @@
+// Copyright The OpenTelemetry Authors
+// SPDX-License-Identifier: Apache-2.0
+
+//go:generate mdatagen metadata.yaml
+package redisstorageextension // import "github.com/open-telemetry/opentelemetry-collector-contrib/extension/storage/redisstorageextension"

extension/storage/redisstorageextension/extension.go

@@ -0,0 +1,131 @@
+// Copyright The OpenTelemetry Authors
+// SPDX-License-Identifier: Apache-2.0
+
+package redisstorageextension // import "github.com/open-telemetry/opentelemetry-collector-contrib/extension/storage/redisstorageextension"
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"time"
+
+	"github.com/redis/go-redis/v9"
+	"go.opentelemetry.io/collector/component"
+	"go.opentelemetry.io/collector/extension"
+	"go.opentelemetry.io/collector/extension/experimental/storage"
+	"go.uber.org/zap"
+)
+
+type redisStorage struct {
+	cfg    *Config
+	logger *zap.Logger
+	client *redis.Client
+}
+
+// Ensure this storage extension implements the appropriate interface
+var _ storage.Extension = (*redisStorage)(nil)
+
+func newRedisStorage(logger *zap.Logger, config *Config) (extension.Extension, error) {
+	return &redisStorage{
+		cfg:    config,
+		logger: logger,
+	}, nil
+}
+
+// Start runs cleanup if configured
+func (rs *redisStorage) Start(context.Context, component.Host) error {
+	c := redis.NewClient(&redis.Options{
+		Addr:     rs.cfg.Endpoint,
+		Password: string(rs.cfg.Password),
+		DB:       rs.cfg.DB,
+	})
+	rs.client = c
+	return nil
+}
+
+// Shutdown will close any open databases
+func (rs *redisStorage) Shutdown(context.Context) error {
+	if rs.client == nil {
+		return nil
+	}
+	return rs.client.Close()
+}
+
+type redisClient struct {
+	client     *redis.Client
+	prefix     string
+	expiration time.Duration
+}
+
+var _ storage.Client = redisClient{}
+
+func (rc redisClient) Get(ctx context.Context, key string) ([]byte, error) {
+	b, err := rc.client.Get(ctx, rc.prefix+key).Bytes()
+	if errors.Is(err, redis.Nil) {
+		return nil, nil
+	}
+	return b, err
+}
+
+func (rc redisClient) Set(ctx context.Context, key string, value []byte) error {
+	_, err := rc.client.Set(ctx, rc.prefix+key, value, rc.expiration).Result()
+	return err
+}
+
+func (rc redisClient) Delete(ctx context.Context, key string) error {
+	_, err := rc.client.Del(ctx, rc.prefix+key).Result()
+	return err
+}
+
+func (rc redisClient) Batch(ctx context.Context, ops ...storage.Operation) error {
+	p := rc.client.Pipeline()
+	for _, op := range ops {
+		switch op.Type {
+		case storage.Delete:
+			p.Del(ctx, op.Key)
+		case storage.Get:
+			p.Get(ctx, op.Key)
+		case storage.Set:
+			p.Set(ctx, op.Key, op.Value, rc.expiration)
+		}
+	}
+	_, err := p.Exec(ctx)
+	return err
+}
+
+func (rc redisClient) Close(_ context.Context) error {
+	return nil
+}
+
+// GetClient returns a storage client for an individual component
+func (rs *redisStorage) GetClient(_ context.Context, kind component.Kind, ent component.ID, name string) (storage.Client, error) {
+	var rawName string
+	if name == "" {
+		rawName = fmt.Sprintf("%s_%s_%s", kindString(kind), ent.Type(), ent.Name())
+	} else {
+		rawName = fmt.Sprintf("%s_%s_%s_%s", kindString(kind), ent.Type(), ent.Name(), name)
+	}
+
+	return redisClient{
+		client:     rs.client,
+		prefix:     rawName,
+		expiration: rs.cfg.Expiration,
+	}, nil
+}
+
+func kindString(k component.Kind) string {
+	switch k {
+	case component.KindReceiver:
+		return "receiver"
+	case component.KindProcessor:
+		return "processor"
+	case component.KindExporter:
+		return "exporter"
+	case component.KindExtension:
+		return "extension"
+	case component.KindConnector:
+		return "connector"
+	default:
+		return "other" // not expected
+	}
+}