Function getIndexes

backend/plugin/db/mongodb/sync.go:198–253

getIndexes returns all indexes schema of a collection. https://www.mongodb.com/docs/manual/reference/command/listIndexes/#output

(ctx context.Context, collection *mongo.Collection)

// getIndexes returns all indexes schema of a collection.
// https://www.mongodb.com/docs/manual/reference/command/listIndexes/#output
func getIndexes(ctx context.Context, collection *mongo.Collection) ([]*storepb.IndexMetadata, error) {
	indexCursor, err := collection.Indexes().List(ctx)
	if err != nil {
		return nil, errors.Wrap(err, "failed to list indexes")
	}
	indexMap := make(map[string]*storepb.IndexMetadata)
	defer indexCursor.Close(ctx)
	for indexCursor.Next(ctx) {
		var indexInfo bson.M
		if err := indexCursor.Decode(&indexInfo); err != nil {
			return nil, errors.Wrap(err, "failed to decode index info")
		}
		name, ok := indexInfo["name"]
		if !ok {
			return nil, errors.New("cannot get index name from index info")
		}
		indexName, ok := name.(string)
		if !ok {
			return nil, errors.New("cannot cinvert index name to string")
		}
		key, ok := indexInfo["key"]
		if !ok {
			return nil, errors.New("cannot get index key from index info")
		}
		expression, err := json.Marshal(key)
		if err != nil {
			return nil, errors.Wrap(err, "cannot marshal index key to json")
		}
		unique := false
		if u, ok := indexInfo["unique"]; ok {
			unique, ok = u.(bool)
			if !ok {
				return nil, errors.New("cannot convert unique to bool")
			}
		}

		if _, ok := indexMap[indexName]; !ok {
			indexMap[indexName] = &storepb.IndexMetadata{
				Name:   indexName,
				Unique: unique,
			}
		}
		indexMap[indexName].Expressions = append(indexMap[indexName].Expressions, string(expression))
	}

	var indexes []*storepb.IndexMetadata
	var indexNames []string
	for name := range indexMap {
		indexNames = append(indexNames, name)
	}
	slices.Sort(indexNames)
	for _, name := range indexNames {
		indexes = append(indexes, indexMap[name])
	}
	return indexes, nil
}

func isSystemCollection(collectionName string) bool {