feat: adding instrumentation support for mongo-driver/v2

instrumentation/README.md

@@ -48,6 +48,7 @@ The following instrumentation packages are provided for popular Go packages and
 | [github.com/gorilla/mux](./github.com/gorilla/mux/otelmux) |  | ✓ |
 | [github.com/labstack/echo](./github.com/labstack/echo/otelecho) |  | ✓ |
 | [go.mongodb.org/mongo-driver](./go.mongodb.org/mongo-driver/mongo/otelmongo) |  | ✓ |
+| [go.mongodb.org/mongo-driver/v2](./go.mongodb.org/mongo-driver/v2/mongo/otelmongo) |  | ✓ |
 | [google.golang.org/grpc](./google.golang.org/grpc/otelgrpc) | ✓ | ✓ |
 | [host](./host) | ✓ |  |
 | [net/http](./net/http/otelhttp) | ✓ | ✓ |

instrumentation/go.mongodb.org/mongo-driver/v2/mongo/otelmongo/config.go

@@ -0,0 +1,68 @@
+// Copyright The OpenTelemetry Authors
+// SPDX-License-Identifier: Apache-2.0
+
+package otelmongo // import "go.opentelemetry.io/contrib/instrumentation/go.mongodb.org/mongo-driver/v2/mongo/otelmongo"
+
+import (
+	"go.opentelemetry.io/otel"
+	"go.opentelemetry.io/otel/trace"
+)
+
+// ScopeName is the instrumentation scope name.
+const ScopeName = "go.opentelemetry.io/contrib/instrumentation/go.mongodb.org/mongo-driver/v2/mongo/otelmongo"
+
+// config is used to configure the mongo tracer.
+type config struct {
+	TracerProvider trace.TracerProvider
+
+	Tracer trace.Tracer
+
+	CommandAttributeDisabled bool
+}
+
+// newConfig returns a config with all Options set.
+func newConfig(opts ...Option) config {
+	cfg := config{
+		TracerProvider:           otel.GetTracerProvider(),
+		CommandAttributeDisabled: true,
+	}
+	for _, opt := range opts {
+		opt.apply(&cfg)
+	}
+
+	cfg.Tracer = cfg.TracerProvider.Tracer(
+		ScopeName,
+		trace.WithInstrumentationVersion(Version()),
+	)
+	return cfg
+}
+
+// Option specifies instrumentation configuration options.
+type Option interface {
+	apply(*config)
+}
+
+type optionFunc func(*config)
+
+func (o optionFunc) apply(c *config) {
+	o(c)
+}
+
+// WithTracerProvider specifies a tracer provider to use for creating a tracer.
+// If none is specified, the global provider is used.
+func WithTracerProvider(provider trace.TracerProvider) Option {
+	return optionFunc(func(cfg *config) {
+		if provider != nil {
+			cfg.TracerProvider = provider
+		}
+	})
+}
+
+// WithCommandAttributeDisabled specifies if the MongoDB command is added as an attribute to Spans or not.
+// This is disabled by default and the MongoDB command will not be added as an attribute
+// to Spans if this option is not provided.
+func WithCommandAttributeDisabled(disabled bool) Option {
+	return optionFunc(func(cfg *config) {
+		cfg.CommandAttributeDisabled = disabled
+	})
+}

instrumentation/go.mongodb.org/mongo-driver/v2/mongo/otelmongo/doc.go

@@ -0,0 +1,15 @@
+// Copyright The OpenTelemetry Authors
+// SPDX-License-Identifier: Apache-2.0
+
+// Package otelmongo instruments go.mongodb.org/mongo-driver/mongo.
+//
+// This package is compatible with v0.2.0 of
+// go.mongodb.org/mongo-driver/mongo.
+//
+// `NewMonitor` will return an event.CommandMonitor which is used to trace
+// requests.
+//
+// This code was originally based on the following:
+// - https://github.com/DataDog/dd-trace-go/tree/02f0449efa3cb382d499fadc873957385dcb2192/contrib/go.mongodb.org/mongo-driver/mongo
+// - https://github.com/DataDog/dd-trace-go/tree/v1.23.3/ddtrace/ext
+package otelmongo // import "go.opentelemetry.io/contrib/instrumentation/go.mongodb.org/mongo-driver/v2/mongo/otelmongo"

instrumentation/go.mongodb.org/mongo-driver/v2/mongo/otelmongo/example_test.go

@@ -0,0 +1,41 @@
+// Copyright The OpenTelemetry Authors
+// SPDX-License-Identifier: Apache-2.0
+
+package otelmongo_test
+
+import (
+	"context"
+
+	"go.mongodb.org/mongo-driver/v2/bson"
+	"go.mongodb.org/mongo-driver/v2/mongo"
+	"go.mongodb.org/mongo-driver/v2/mongo/options"
+
+	"go.opentelemetry.io/contrib/instrumentation/go.mongodb.org/mongo-driver/v2/mongo/otelmongo"
+)
+
+func Example() {
+	// connect to MongoDB
+	opts := options.Client()
+	opts.Monitor = otelmongo.NewMonitor()
+	opts.ApplyURI("mongodb://localhost:27017")
+	client, err := mongo.Connect(opts)
+	if err != nil {
+		panic(err)
+	}
+	db := client.Database("example")
+	inventory := db.Collection("inventory")
+
+	_, err = inventory.InsertOne(context.Background(), bson.D{
+		{Key: "item", Value: "canvas"},
+		{Key: "qty", Value: 100},
+		{Key: "attributes", Value: bson.A{"cotton"}},
+		{Key: "size", Value: bson.D{
+			{Key: "h", Value: 28},
+			{Key: "w", Value: 35.5},
+			{Key: "uom", Value: "cm"},
+		}},
+	})
+	if err != nil {
+		panic(err)
+	}
+}

instrumentation/go.mongodb.org/mongo-driver/v2/mongo/otelmongo/go.mod

@@ -0,0 +1,29 @@
+module go.opentelemetry.io/contrib/instrumentation/go.mongodb.org/mongo-driver/v2/mongo/otelmongo
+
+go 1.22.0
+
+require (
+	github.com/stretchr/testify v1.10.0
+	go.mongodb.org/mongo-driver/v2 v2.0.0
+	go.opentelemetry.io/otel v1.33.0
+	go.opentelemetry.io/otel/trace v1.33.0
+)
+
+require (
+	github.com/davecgh/go-spew v1.1.1 // indirect
+	github.com/go-logr/logr v1.4.2 // indirect
+	github.com/go-logr/stdr v1.2.2 // indirect
+	github.com/golang/snappy v0.0.4 // indirect
+	github.com/klauspost/compress v1.17.11 // indirect
+	github.com/pmezard/go-difflib v1.0.0 // indirect
+	github.com/xdg-go/pbkdf2 v1.0.0 // indirect
+	github.com/xdg-go/scram v1.1.2 // indirect
+	github.com/xdg-go/stringprep v1.0.4 // indirect
+	github.com/youmark/pkcs8 v0.0.0-20240726163527-a2c0da244d78 // indirect
+	go.opentelemetry.io/auto/sdk v1.1.0 // indirect
+	go.opentelemetry.io/otel/metric v1.33.0 // indirect
+	golang.org/x/crypto v0.31.0 // indirect
+	golang.org/x/sync v0.10.0 // indirect
+	golang.org/x/text v0.21.0 // indirect
+	gopkg.in/yaml.v3 v3.0.1 // indirect
+)

instrumentation/go.mongodb.org/mongo-driver/v2/mongo/otelmongo/go.sum

@@ -0,0 +1,76 @@
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instrumentation/go.mongodb.org/mongo-driver/v2/mongo/otelmongo/mongo.go

@@ -0,0 +1,150 @@
+// Copyright The OpenTelemetry Authors
+// SPDX-License-Identifier: Apache-2.0
+
+package otelmongo // import "go.opentelemetry.io/contrib/instrumentation/go.mongodb.org/mongo-driver/v2/mongo/otelmongo"
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"strconv"
+	"strings"
+	"sync"
+
+	"go.opentelemetry.io/otel/attribute"
+	"go.opentelemetry.io/otel/codes"
+	semconv "go.opentelemetry.io/otel/semconv/v1.21.0"
+	"go.opentelemetry.io/otel/trace"
+
+	"go.mongodb.org/mongo-driver/v2/bson"
+	"go.mongodb.org/mongo-driver/v2/event"
+)
+
+type spanKey struct {
+	ConnectionID string
+	RequestID    int64
+}
+
+type monitor struct {
+	sync.Mutex
+	spans map[spanKey]trace.Span
+	cfg   config
+}
+
+func (m *monitor) Started(ctx context.Context, evt *event.CommandStartedEvent) {
+	var spanName string
+
+	hostname, port := peerInfo(evt)
+
+	attrs := []attribute.KeyValue{
+		semconv.DBSystemMongoDB,
+		semconv.DBOperation(evt.CommandName),
+		semconv.DBName(evt.DatabaseName),
+		semconv.NetPeerName(hostname),
+		semconv.NetPeerPort(port),
+		semconv.NetTransportTCP,
+	}
+	if !m.cfg.CommandAttributeDisabled {
+		attrs = append(attrs, semconv.DBStatement(sanitizeCommand(evt.Command)))
+	}
+	if collection, err := extractCollection(evt); err == nil && collection != "" {
+		spanName = collection + "."
+		attrs = append(attrs, semconv.DBMongoDBCollection(collection))
+	}
+	spanName += evt.CommandName
+	opts := []trace.SpanStartOption{
+		trace.WithSpanKind(trace.SpanKindClient),
+		trace.WithAttributes(attrs...),
+	}
+	_, span := m.cfg.Tracer.Start(ctx, spanName, opts...)
+	key := spanKey{
+		ConnectionID: evt.ConnectionID,
+		RequestID:    evt.RequestID,
+	}
+	m.Lock()
+	m.spans[key] = span
+	m.Unlock()
+}
+
+func (m *monitor) Succeeded(ctx context.Context, evt *event.CommandSucceededEvent) {
+	m.Finished(&evt.CommandFinishedEvent, nil)
+}
+
+func (m *monitor) Failed(ctx context.Context, evt *event.CommandFailedEvent) {
+	m.Finished(&evt.CommandFinishedEvent, fmt.Errorf("%w", evt.Failure))
+}
+
+func (m *monitor) Finished(evt *event.CommandFinishedEvent, err error) {
+	key := spanKey{
+		ConnectionID: evt.ConnectionID,
+		RequestID:    evt.RequestID,
+	}
+	m.Lock()
+	span, ok := m.spans[key]
+	if ok {
+		delete(m.spans, key)
+	}
+	m.Unlock()
+	if !ok {
+		return
+	}
+
+	if err != nil {
+		span.SetStatus(codes.Error, err.Error())
+	}
+
+	span.End()
+}
+
+// TODO sanitize values where possible, then re-enable `db.statement` span attributes default.
+// TODO limit maximum size.
+func sanitizeCommand(command bson.Raw) string {
+	b, _ := bson.MarshalExtJSON(command, false, false)
+	return string(b)
+}
+
+// extractCollection extracts the collection for the given mongodb command event.
+// For CRUD operations, this is the first key/value string pair in the bson
+// document where key == "<operation>" (e.g. key == "insert").
+// For database meta-level operations, such a key may not exist.
+func extractCollection(evt *event.CommandStartedEvent) (string, error) {
+	elt, err := evt.Command.IndexErr(0)
+	if err != nil {
+		return "", err
+	}
+	if key, err := elt.KeyErr(); err == nil && key == evt.CommandName {
+		var v bson.RawValue
+		if v, err = elt.ValueErr(); err != nil || v.Type != bson.TypeString {
+			return "", err
+		}
+		return v.StringValue(), nil
+	}
+	return "", errors.New("collection name not found")
+}
+
+// NewMonitor creates a new mongodb event CommandMonitor.
+func NewMonitor(opts ...Option) *event.CommandMonitor {
+	cfg := newConfig(opts...)
+	m := &monitor{
+		spans: make(map[spanKey]trace.Span),
+		cfg:   cfg,
+	}
+	return &event.CommandMonitor{
+		Started:   m.Started,
+		Succeeded: m.Succeeded,
+		Failed:    m.Failed,
+	}
+}
+
+func peerInfo(evt *event.CommandStartedEvent) (hostname string, port int) {
+	hostname = evt.ConnectionID
+	port = 27017
+	if idx := strings.IndexByte(hostname, '['); idx >= 0 {
+		hostname = hostname[:idx]
+	}
+	if idx := strings.IndexByte(hostname, ':'); idx >= 0 {
+		port = func(p int, e error) int { return p }(strconv.Atoi(hostname[idx+1:]))
+		hostname = hostname[:idx]
+	}
+	return hostname, port
+}