From the Connection.prototype.db documentation:
The mongodb.Db instance, set when the connection is opened
This means the mongoose.connection.db will be set when the connection is opened. Before the connection is opened, the value is undefined. That's why you got the error, gridfs-stream library will validate the parameters here 1.1.1/lib/index.js#L25
Connect the database server first using mongoose.connect() method.
import Grid from 'gridfs-stream';
import mongoose from 'mongoose';
import { config } from '../../config';
(async function main() {
try {
console.log('Before DB connected: ', mongoose.connection.db);
await mongoose.connect(config.MONGODB_URI);
const { db } = mongoose.connection;
console.log('DB connected: ', db);
const mongo = mongoose.mongo;
const gfs = Grid(db, mongo);
console.log(gfs);
} catch (error) {
console.error(error);
} finally {
await mongoose.connection.close();
}
})();
Logs:
Before DB connected: undefined
DB connected: Db {
s: {
options: {
enableUtf8Validation: true,
forceServerObjectId: false,
pkFactory: [Object],
raw: false,
readPreference: [ReadPreference],
retryWrites: true
},
readPreference: ReadPreference {
mode: 'primary',
tags: undefined,
hedge: undefined,
maxStalenessSeconds: undefined,
minWireVersion: undefined
},
bsonOptions: {
raw: false,
useBigInt64: false,
promoteLongs: true,
promoteValues: true,
promoteBuffers: false,
ignoreUndefined: false,
bsonRegExp: false,
serializeFunctions: false,
fieldsAsRaw: {},
enableUtf8Validation: true
},
pkFactory: { createPk: [Function: createPk] },
readConcern: undefined,
writeConcern: undefined,
namespace: MongoDBNamespace { db: 'test', collection: undefined }
},
client: <ref *1> MongoClient {
_events: [Object: null prototype] {
topologyDescriptionChanged: [Function (anonymous)]
},
_eventsCount: 1,
_maxListeners: 0,
mongoLogger: MongoLogger {
error: [Function: bound log],
warn: [Function: bound log],
info: [Function: bound log],
debug: [Function: bound log],
trace: [Function: bound log],
componentSeverities: [Object],
maxDocumentLength: 1000,
logDestination: [Object]
},
s: {
url: 'mongodb+srv://slideshowp2:xtEBJWGgFXSNbv6t@cluster0.d1avjia.mongodb.net',
bsonOptions: [Object],
namespace: [MongoDBNamespace],
hasBeenClosed: false,
sessionPool: [ServerSessionPool],
activeSessions: Set(0) {},
options: [Getter],
readConcern: [Getter],
writeConcern: [Getter],
readPreference: [Getter],
isMongoClient: [Getter]
},
connectionLock: undefined,
topology: Topology {
_events: [Object: null prototype],
_eventsCount: 26,
_maxListeners: undefined,
client: [Circular *1],
selectServerAsync: [Function (anonymous)],
s: [Object],
[Symbol(kCapture)]: false,
[Symbol(waitQueue)]: [List]
},
[Symbol(kCapture)]: false,
[Symbol(options)]: [Object: null prototype] {
hosts: [Array],
credentials: [MongoCredentials],
compressors: [Array],
connectTimeoutMS: 30000,
directConnection: false,
driverInfo: [Object],
enableUtf8Validation: true,
forceServerObjectId: false,
heartbeatFrequencyMS: 10000,
keepAlive: true,
keepAliveInitialDelay: 120000,
loadBalanced: false,
localThresholdMS: 15,
maxConnecting: 2,
maxIdleTimeMS: 0,
maxPoolSize: 100,
minPoolSize: 0,
minHeartbeatFrequencyMS: 500,
monitorCommands: false,
noDelay: true,
pkFactory: [Object],
raw: false,
readPreference: [ReadPreference],
retryReads: true,
retryWrites: true,
serverSelectionTimeoutMS: 30000,
socketTimeoutMS: 0,
srvMaxHosts: 0,
srvServiceName: 'mongodb',
waitQueueTimeoutMS: 0,
zlibCompressionLevel: 0,
dbName: 'test',
userSpecifiedAuthSource: false,
userSpecifiedReplicaSet: false,
srvHost: 'cluster0.d1avjia.mongodb.net',
tls: true,
mongoLoggerOptions: [Object],
metadata: [Object],
replicaSet: 'atlas-zy5qpa-shard-0',
[Symbol(@@mdb.enableMongoLogger)]: false
}
}
}
Grid {
db: Db {
s: {
options: [Object],
readPreference: [ReadPreference],
bsonOptions: [Object],
pkFactory: [Object],
readConcern: undefined,
writeConcern: undefined,
namespace: [MongoDBNamespace]
},
client: MongoClient {
_events: [Object: null prototype],
_eventsCount: 1,
_maxListeners: 0,
mongoLogger: [MongoLogger],
s: [Object],
connectionLock: undefined,
topology: [Topology],
[Symbol(kCapture)]: false,
[Symbol(options)]: [Object: null prototype]
}
},
mongo: {
BSON: [Getter],
Binary: [Getter],
BSONRegExp: [Getter],
BSONSymbol: [Getter],
BSONType: [Getter],
Code: [Getter],
DBRef: [Getter],
Decimal128: [Getter],
Double: [Getter],
Int32: [Getter],
Long: [Getter],
MaxKey: [Getter],
MinKey: [Getter],
ObjectId: [Getter],
Timestamp: [Getter],
MongoBulkWriteError: [Getter],
ChangeStreamCursor: [Getter],
MongoAPIError: [Getter],
MongoAWSError: [Getter],
MongoBatchReExecutionError: [Getter],
MongoChangeStreamError: [Getter],
MongoCompatibilityError: [Getter],
MongoCursorExhaustedError: [Getter],
MongoCursorInUseError: [Getter],
MongoDecompressionError: [Getter],
MongoDriverError: [Getter],
MongoError: [Getter],
MongoExpiredSessionError: [Getter],
MongoGridFSChunkError: [Getter],
MongoGridFSStreamError: [Getter],
MongoInvalidArgumentError: [Getter],
MongoKerberosError: [Getter],
MongoMissingCredentialsError: [Getter],
MongoMissingDependencyError: [Getter],
MongoNetworkError: [Getter],
MongoNetworkTimeoutError: [Getter],
MongoNotConnectedError: [Getter],
MongoParseError: [Getter],
MongoRuntimeError: [Getter],
MongoServerClosedError: [Getter],
MongoServerError: [Getter],
MongoServerSelectionError: [Getter],
MongoSystemError: [Getter],
MongoTailableCursorError: [Getter],
MongoTopologyClosedError: [Getter],
MongoTransactionError: [Getter],
MongoUnexpectedServerResponseError: [Getter],
MongoWriteConcernError: [Getter],
AbstractCursor: [Getter],
Admin: [Getter],
AggregationCursor: [Getter],
CancellationToken: [Getter],
ChangeStream: [Getter],
ClientSession: [Getter],
Collection: [Getter],
Db: [Getter],
FindCursor: [Getter],
GridFSBucket: [Getter],
GridFSBucketReadStream: [Getter],
GridFSBucketWriteStream: [Getter],
ListCollectionsCursor: [Getter],
ListIndexesCursor: [Getter],
MongoClient: [Getter],
OrderedBulkOperation: [Getter],
UnorderedBulkOperation: [Getter],
BatchType: [Getter],
GSSAPICanonicalizationValue: [Getter],
AuthMechanism: [Getter],
Compressor: [Getter],
CURSOR_FLAGS: [Getter],
AutoEncryptionLoggerLevel: [Getter],
MongoErrorLabel: [Getter],
ExplainVerbosity: [Getter],
ServerApiVersion: [Getter],
ReturnDocument: [Getter],
ProfilingLevel: [Getter],
ReadConcernLevel: [Getter],
ReadPreferenceMode: [Getter],
ServerType: [Getter],
TopologyType: [Getter],
ReadConcern: [Getter],
ReadPreference: [Getter],
WriteConcern: [Getter],
CommandFailedEvent: [Getter],
CommandStartedEvent: [Getter],
CommandSucceededEvent: [Getter],
ConnectionCheckedInEvent: [Getter],
ConnectionCheckedOutEvent: [Getter],
ConnectionCheckOutFailedEvent: [Getter],
ConnectionCheckOutStartedEvent: [Getter],
ConnectionClosedEvent: [Getter],
ConnectionCreatedEvent: [Getter],
ConnectionPoolClearedEvent: [Getter],
ConnectionPoolClosedEvent: [Getter],
ConnectionPoolCreatedEvent: [Getter],
ConnectionPoolMonitoringEvent: [Getter],
ConnectionPoolReadyEvent: [Getter],
ConnectionReadyEvent: [Getter],
ServerClosedEvent: [Getter],
ServerDescriptionChangedEvent: [Getter],
ServerHeartbeatFailedEvent: [Getter],
ServerHeartbeatStartedEvent: [Getter],
ServerHeartbeatSucceededEvent: [Getter],
ServerOpeningEvent: [Getter],
TopologyClosedEvent: [Getter],
TopologyDescriptionChangedEvent: [Getter],
TopologyOpeningEvent: [Getter],
SrvPollingEvent: [Getter]
},
curCol: 'fs'
}
package versions:
"gridfs-stream": "^1.1.1",
"mongoose": "^7.3.1",
