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Merged
adiom-mark merged 1 commit into from
Feb 11, 2026
Merged

Add full-document-key opt to mongo connector. #366

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3 changes: 3 additions & 0 deletions connectors/cosmos/conn.go
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -279,6 +279,7 @@ func convertChangeStreamEventToUpdate(change bson.M) (*adiomv1.Update, error) {
Id: []*adiomv1.BsonValue{{
Data: idVal,
Type: uint32(idType),
Name: "_id",
}},
Type: adiomv1.UpdateType_UPDATE_TYPE_DELETE,
}, nil
Expand All @@ -299,6 +300,7 @@ func convertChangeStreamEventToUpdate(change bson.M) (*adiomv1.Update, error) {
Id: []*adiomv1.BsonValue{{
Data: idVal,
Type: uint32(idType),
Name: "_id",
}},
Type: adiomv1.UpdateType_UPDATE_TYPE_UPDATE,
Data: fullDocumentRaw,
Expand Down Expand Up @@ -333,6 +335,7 @@ func checkForDeletes(ctx context.Context, client *mongo.Client, witnessClient *m
Id: []*adiomv1.BsonValue{{
Data: idVal,
Type: uint32(idType),
Name: "_id",
}},
Type: adiomv1.UpdateType_UPDATE_TYPE_DELETE,
})
Expand Down
153 changes: 63 additions & 90 deletions connectors/mongo/conn.go
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Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -16,10 +16,10 @@ import (
"time"

"connectrpc.com/connect"
"github.com/adiom-data/dsync/connectors/util"
adiomv1 "github.com/adiom-data/dsync/gen/adiom/v1"
"github.com/adiom-data/dsync/gen/adiom/v1/adiomv1connect"
"github.com/adiom-data/dsync/protocol/iface"
"github.com/cespare/xxhash"
"go.mongodb.org/mongo-driver/bson"
"go.mongodb.org/mongo-driver/bson/bsontype"
"go.mongodb.org/mongo-driver/bson/primitive"
Expand All @@ -41,6 +41,7 @@ type ConnectorSettings struct {
MaxPageSize int
PerNamespaceStreams bool
SkipBatchOverwrite bool
FullDocumentKey bool

Query string // query filter, as a v2 Extended JSON string, e.g., '{\"x\":{\"$gt\":1}}'"
}
Expand Down Expand Up @@ -611,75 +612,61 @@ func createChangeStreamNamespaceFilterFromNamespaces(namespaces []iface.Namespac
return bson.D{{"$or", filters}}
}

func convertChangeStreamEventToUpdate(change bson.M) (*adiomv1.Update, error) {
func convertChangeStreamEventToUpdate(change MongoUpdate, fullDocumentKey bool) (*adiomv1.Update, error) {
// slog.Debug(fmt.Sprintf("Converting change stream event %v", change))

optype := change["operationType"].(string)
optype := change.OperationType
var update *adiomv1.Update

switch optype {
case "insert":
// get the id of the document that was inserted
id := change["documentKey"].(bson.M)["_id"]
// convert id to raw bson
idType, idVal, err := bson.MarshalValue(id)
var id []*adiomv1.BsonValue
for _, k := range change.DocumentKey {
if !fullDocumentKey && k.Key != "_id" {
continue
}
idType, idVal, err := bson.MarshalValue(k.Value)
if err != nil {
return nil, fmt.Errorf("failed to marshal _id: %v", err)
return nil, fmt.Errorf("failed to marshal %v: %v", k.Key, err)
}
fullDocument := change["fullDocument"].(bson.M)
id = append(id, &adiomv1.BsonValue{
Data: idVal,
Type: uint32(idType),
Name: k.Key,
})
}

switch optype {
case "insert":
fullDocument := change.FullDocument
// convert fulldocument to BSON.Raw
fullDocumentRaw, err := bson.Marshal(fullDocument)
if err != nil {
return nil, fmt.Errorf("failed to marshal full document: %v", err)
}
update = &adiomv1.Update{
Id: []*adiomv1.BsonValue{{
Data: idVal,
Type: uint32(idType),
}},
Id: id,
Type: adiomv1.UpdateType_UPDATE_TYPE_INSERT,
Data: fullDocumentRaw,
}
case "update", "replace":
// get the id of the document that was changed
id := change["documentKey"].(bson.M)["_id"]
// convert id to raw bson
idType, idVal, err := bson.MarshalValue(id)
if err != nil {
return nil, fmt.Errorf("failed to marshal _id: %v", err)
}
// get the full state of the document after the change
if change["fullDocument"] == nil {
if change.FullDocument == nil {
//TODO (AK, 6/2024): find a better way to report that we need to ignore this event
return nil, nil // no full document, nothing to do (probably got deleted before we got to the event in the change stream)
}
fullDocument := change["fullDocument"].(bson.M)
fullDocument := change.FullDocument
// convert fulldocument to BSON.Raw
fullDocumentRaw, err := bson.Marshal(fullDocument)
if err != nil {
return nil, fmt.Errorf("failed to marshal full document: %v", err)
}
update = &adiomv1.Update{
Id: []*adiomv1.BsonValue{{
Data: idVal,
Type: uint32(idType),
}},
Id: id,
Type: adiomv1.UpdateType_UPDATE_TYPE_UPDATE,
Data: fullDocumentRaw,
}
case "delete":
// get the id of the document that was deleted
id := change["documentKey"].(bson.M)["_id"]
// convert id to raw bson
idType, idVal, err := bson.MarshalValue(id)
if err != nil {
return nil, fmt.Errorf("failed to marshal _id: %v", err)
}
update = &adiomv1.Update{
Id: []*adiomv1.BsonValue{{
Data: idVal,
Type: uint32(idType),
}},
Id: id,
Type: adiomv1.UpdateType_UPDATE_TYPE_DELETE,
}
default:
Expand All @@ -696,6 +683,14 @@ func toTimestampPB(t primitive.Timestamp) *timestamppb.Timestamp {
return timestamppb.New(time.Unix(int64(t.T), 0))
}

type MongoUpdate struct {
NS bson.M `bson:"ns"`
ClusterTime *primitive.Timestamp `bson:"clusterTime"`
DocumentKey bson.D `bson:"documentKey"`
FullDocument bson.M `bson:"fullDocument"`
OperationType string `bson:"operationType"`
}

// StreamUpdates implements adiomv1connect.ConnectorServiceHandler.
func (c *conn) StreamUpdates(ctx context.Context, r *connect.Request[adiomv1.StreamUpdatesRequest], s *connect.ServerStream[adiomv1.StreamUpdatesResponse]) error {
var watcher Watchable
Expand Down Expand Up @@ -739,13 +734,13 @@ func (c *conn) StreamUpdates(ctx context.Context, r *connect.Request[adiomv1.Str
var lastTime primitive.Timestamp

for changeStream.Next(ctx) {
var change bson.M
var change MongoUpdate
if err := changeStream.Decode(&change); err != nil {
slog.Error(fmt.Sprintf("Failed to decode change stream event: %v", err))
continue
}

update, err := convertChangeStreamEventToUpdate(change)
update, err := convertChangeStreamEventToUpdate(change, c.settings.FullDocumentKey)
if err != nil {
slog.Error(fmt.Sprintf("Failed to convert change stream event to data message: %v", err))
continue
Expand All @@ -754,8 +749,8 @@ func (c *conn) StreamUpdates(ctx context.Context, r *connect.Request[adiomv1.Str
continue
}

db := change["ns"].(bson.M)["db"].(string)
col := change["ns"].(bson.M)["coll"].(string)
db := change.NS["db"].(string)
col := change.NS["coll"].(string)
Comment on lines +752 to +753
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@coderabbitai coderabbitai bot Feb 7, 2026

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⚠️ Potential issue | 🟡 Minor

Unsafe type assertions on change.NS will panic on unexpected data.

change.NS["db"].(string) and change.NS["coll"].(string) are bare type assertions. If the key is missing or the value isn't a string, this panics and kills the stream goroutine. While MongoDB guarantees these for standard CRUD events, defensive assertions are cheap insurance.

🛡️ Suggested defensive approach 
-		db := change.NS["db"].(string)
-		col := change.NS["coll"].(string)
+		db, _ := change.NS["db"].(string)
+		col, _ := change.NS["coll"].(string)
+		if db == "" || col == "" {
+			slog.Error(fmt.Sprintf("Skipping change event with invalid namespace: %v", change.NS))
+			continue
+		}
📝 Committable suggestion

‼️ IMPORTANT
Carefully review the code before committing. Ensure that it accurately replaces the highlighted code, contains no missing lines, and has no issues with indentation. Thoroughly test & benchmark the code to ensure it meets the requirements.

Suggested change
db := change.NS["db"].(string)
col := change.NS["coll"].(string)
db, _ := change.NS["db"].(string)
col, _ := change.NS["coll"].(string)
if db == "" || col == "" {
slog.Error(fmt.Sprintf("Skipping change event with invalid namespace: %v", change.NS))
continue
}
🤖 Prompt for AI Agents 
In `@connectors/mongo/conn.go` around lines 752 - 753, The code uses unsafe type
assertions change.NS["db"].(string) and change.NS["coll"].(string) which can
panic; update the handler around change.NS to perform safe type checks (value,
ok := change.NS["db"]; db, ok2 := value.(string)) and similarly for "coll",
logging an error and skipping the change or returning early if either key is
missing or not a string. Locate this in the change stream processing where
variables db and col are set and replace the bare assertions with the safe-ok
pattern, ensuring you handle the fallback path (log the unexpected shape and
continue) instead of letting the goroutine crash.

newNamespace := fmt.Sprintf("%v.%v", db, col)

if currentNamespace == "" || currentNamespace != newNamespace {
Expand All @@ -779,8 +774,8 @@ func (c *conn) StreamUpdates(ctx context.Context, r *connect.Request[adiomv1.Str

updates = append(updates, update)
lastResumeToken = changeStream.ResumeToken()
if lt, ok := change["clusterTime"].(primitive.Timestamp); ok {
lastTime = lt
if change.ClusterTime != nil {
lastTime = *change.ClusterTime
}

if changeStream.RemainingBatchLength() == 0 {
Expand Down Expand Up @@ -914,63 +909,41 @@ func (c *conn) WriteData(ctx context.Context, r *connect.Request[adiomv1.WriteDa
return connect.NewResponse(&adiomv1.WriteDataResponse{}), nil
}

type dataIdIndex struct {
dataId []byte
index int
}

// returns the new item or existing item, and whether or not a new item was added
func addToIdIndexMap2(m map[int][]*dataIdIndex, update *adiomv1.Update) (*dataIdIndex, bool) {
hasher := xxhash.New()
_, _ = hasher.Write(update.GetId()[0].GetData())
h := int(hasher.Sum64())
items, found := m[h]
if found {
for _, item := range items {
if slices.Equal(item.dataId, update.GetId()[0].GetData()) {
return item, false
}
}
}
item := &dataIdIndex{update.GetId()[0].GetData(), -1}
m[h] = append(items, item)
return item, true
}

// WriteUpdates implements adiomv1connect.ConnectorServiceHandler.
func (c *conn) WriteUpdates(ctx context.Context, r *connect.Request[adiomv1.WriteUpdatesRequest]) (*connect.Response[adiomv1.WriteUpdatesResponse], error) {
col, _, ok := GetCol(c.client, r.Msg.GetNamespace())
if !ok {
return nil, connect.NewError(connect.CodeInvalidArgument, fmt.Errorf("namespace should be fully qualified"))
}
updates := util.KeepLastUpdate(r.Msg.GetUpdates())
var models []mongo.WriteModel
// keeps track of the index in models for a particular document because we want all ids to be unique in the batch
hashToDataIdIndex := map[int][]*dataIdIndex{}

for _, update := range r.Msg.GetUpdates() {
idType := bsontype.Type(update.GetId()[0].GetType())

for _, update := range updates {
var idFilter bson.D
if len(update.GetId()) == 0 {
return nil, connect.NewError(connect.CodeInvalidArgument, fmt.Errorf("err update with unexpected empty id"))
}
for _, idPart := range update.GetId() {
key := idPart.GetName()
// For backwards compatibility- we used to pass no key
if key == "" {
key = "_id"
}
if !c.settings.FullDocumentKey && key != "_id" {
continue
}
typ := bsontype.Type(idPart.GetType())
idFilter = append(idFilter, bson.E{Key: key, Value: bson.RawValue{Type: typ, Value: idPart.GetData()}})
}
if len(idFilter) == 0 {
return nil, connect.NewError(connect.CodeInvalidArgument, fmt.Errorf("err with _id not found- enable full-document-key or ensure an id part has the name _id: %v", update.GetId()))
}
switch update.GetType() {
case adiomv1.UpdateType_UPDATE_TYPE_INSERT, adiomv1.UpdateType_UPDATE_TYPE_UPDATE:
dii, isNew := addToIdIndexMap2(hashToDataIdIndex, update)
idFilter := bson.D{{Key: "_id", Value: bson.RawValue{Type: idType, Value: update.GetId()[0].GetData()}}}
model := mongo.NewReplaceOneModel().SetFilter(idFilter).SetReplacement(bson.Raw(update.GetData())).SetUpsert(true)
if isNew {
dii.index = len(models)
models = append(models, model)
} else {
models[dii.index] = model
}
models = append(models, model)
case adiomv1.UpdateType_UPDATE_TYPE_DELETE:
dii, isNew := addToIdIndexMap2(hashToDataIdIndex, update)
idFilter := bson.D{{Key: "_id", Value: bson.RawValue{Type: idType, Value: update.GetId()[0].GetData()}}}
model := mongo.NewDeleteOneModel().SetFilter(idFilter)
if isNew {
dii.index = len(models)
models = append(models, model)
} else {
models[dii.index] = model
}
models = append(models, model)
}
}

Expand Down
5 changes: 5 additions & 0 deletions internal/app/options/connectorflags.go
View file
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Original file line number Diff line number Diff line change
Expand Up @@ -760,6 +760,11 @@ func MongoFlags(settings *mongo.ConnectorSettings) []cli.Flag {
Name: "skip-batch-overwrite",
Destination: &settings.SkipBatchOverwrite,
}),
altsrc.NewBoolFlag(&cli.BoolFlag{
Name: "full-document-key",
Usage: "uses the full document key instead of just _id (except for batch overwrites)",
Destination: &settings.FullDocumentKey,
}),
altsrc.NewDurationFlag(&cli.DurationFlag{
Name: "server-timeout",
Required: false,
Expand Down