Cloud Logging allows you to store, search, analyze, monitor, and alert on log data and events from Google Cloud Platform and Amazon Web Services (AWS).
See Introduction to the Cloud Logging API
Package
@google-cloud/loggingExamples
Import the client library
const
{
Logging
}
=
require
(
' @google-cloud/logging
'
);
Create a client that uses Application Default Credentials (ADC) :
const
logging
=
new
Logging
();
Create a client with explicitcredentials :
const
logging
=
new
Logging
({
projectId
:
'your-project-id'
,
keyFilename
:
'/path/to/keyfile.json'
});
Full quickstart example:
// Imports the Google Cloud client library
const
{
Logging
}
=
require
(
' @google-cloud/logging
'
);
async
function
quickstart
(
projectId
=
'YOUR_PROJECT_ID'
,
// Your Google Cloud Platform project ID
logName
=
'my-log'
// The name of the log to write to
)
{
// Creates a client
const
logging
=
new
Logging
({
projectId
});
// Selects the log to write to
const
log
=
logging
.
log
(
logName
);
// The data to write to the log
const
text
=
'Hello, world!'
;
// The metadata associated with the entry
const
metadata
=
{
resource
:
{
type
:
'global'
},
// See: https://cloud.google.com/logging/docs/reference/v2/rest/v2/LogEntry#logseverity
severity
:
' INFO
'
,
};
// Prepares a log entry
const
entry
=
log
.
entry
(
metadata
,
text
);
async
function
writeLog
()
{
// Writes the log entry
await
log
.
write
(
entry
);
console
.
log
(
`Logged:
${
text
}
`
);
}
writeLog
();
}
Constructors
(constructor)(options, gaxInstance)
constructor
(
options
?:
LoggingOptions
,
gaxInstance
?:
typeof
gax
);
Constructs a new instance of the Logging
class
Properties
api
api
:
{
[
key
:
string
]
:
gax
.
ClientStub
;
};
auth
auth
:
gax
.
GoogleAuth
;
configService
configService
?:
typeof
v2
.
ConfigServiceV2Client
;
detectedResource
detectedResource
?:
object
;
loggingService
loggingService
?:
typeof
v2
.
LoggingServiceV2Client
;
options
options
:
LoggingOptions
;
projectId
projectId
:
string
;
Methods
createSink(name, config)
createSink
(
name
:
string
,
config
:
CreateSinkRequest
)
:
Promise
< [
Sink
,
LogSink
]>;
CreateSinkCallback
createSink(name, config, callback)
createSink
(
name
:
string
,
config
:
CreateSinkRequest
,
callback
:
CreateSinkCallback
)
:
void
;
Returns
Type
Description
void
entry(resource, data)
entry
(
resource
?:
LogEntry
,
data
?:
{}
|
string
)
:
Entry
;
Create an entry object.
Using this method will not itself make any API requests. You will use the object returned in other API calls, such as .
Note, Cloud Logging Quotas and limits dictates that the maximum log entry size, including all [LogEntry Resource properties] https://cloud.google.com/logging/docs/reference/v2/rest/v2/LogEntry , cannot exceed _approximately_ 256 KB.
Parameters
Name
Description
resource
LogEntry
See a [Monitored Resource]( https://cloud.google.com/logging/docs/reference/v2/rest/v2/MonitoredResource ).
data
{} | string
The data to use as the value for this log entry.
Returns
Type
Description
Entry
{Entry}
const
{
Logging
}
=
require
(
' @google-cloud/logging
'
);
const
logging
=
new
Logging
();
const
resource
=
{
type
:
'gce_instance'
,
labels
:
{
zone
:
'global'
,
instance_id
:
'3'
}
};
const
entry
=
logging
.
entry
(
resource
,
{
delegate
:
'my_username'
});
entry
.
toJSON
();
// {
// resource: {
// type: 'gce_instance',
// labels: {
// zone: 'global',
// instance_id: '3'
// }
// },
// jsonPayload: {
// delegate: 'my_username'
// }
// }
getEntries(options)
getEntries
(
options
?:
GetEntriesRequest
)
:
Promise<GetEntriesResponse>
;
List the entries in your logs.
Parameter
Name
Description
options
GetEntriesRequest
const
{
Logging
}
=
require
(
' @google-cloud/logging
'
);
const
logging
=
new
Logging
();
logging
.
getEntries
((
err
,
entries
)
=
>
{
// `entries` is an array of Cloud Logging entry objects.
// See the `data` property to read the data from the entry.
});
//-
// To control how many API requests are made and page through the results
// manually, set `autoPaginate` to `false`.
//-
function
callback
(
err
,
entries
,
nextQuery
,
apiResponse
)
{
if
(
nextQuery
)
{
// More results exist.
logging
.
getEntries
(
nextQuery
,
callback
);
}
}
logging
.
getEntries
({
autoPaginate
:
false
},
callback
);
//-
// If the callback is omitted, we'll return a Promise.
//-
logging
.
getEntries
().
then
(
data
=
>
{
const
entries
=
data
[
0
];
});
Another example:
// Imports the Google Cloud client library
const
{
Logging
}
=
require
(
' @google-cloud/logging
'
);
// Creates a client
const
logging
=
new
Logging
();
/**
* TODO(developer): Uncomment the following line to run the code.
*/
// const logName = 'Name of the log from which to list entries, e.g. my-log';
const
log
=
logging
.
log
(
logName
);
async
function
printEntryMetadata
()
{
// List the most recent entries for a given log
// See https://googleapis.dev/nodejs/logging/latest/Logging.html#getEntries
const
[
entries
]
=
await
log
.
getEntries
();
console
.
log
(
'Logs:'
);
entries
.
forEach
(
entry
=
>
{
const
metadata
=
entry
.
metadata
;
console
.
log
(
`
${
metadata
.
timestamp
}
:`
,
metadata
[
metadata
.
payload
]);
});
}
printEntryMetadata
();
Another example:
// Imports the Google Cloud client library
const
{
Logging
}
=
require
(
' @google-cloud/logging
'
);
// Creates a client
const
logging
=
new
Logging
();
/**
* TODO(developer): Uncomment the following lines to run the code.
*
* Filter results, e.g. "severity=ERROR"
* See https://cloud.google.com/logging/docs/view/advanced_filters for more
* filter information.
*/
// const filter = 'severity=ERROR';
// const pageSize = 5;
// const orderBy = 'timestamp desc';
const
options
=
{
filter
:
filter
,
pageSize
:
pageSize
,
orderBy
:
orderBy
,
};
async
function
printEntryMetadata
()
{
// See https://googleapis.dev/nodejs/logging/latest/Logging.html#getEntries
const
[
entries
]
=
await
logging
.
getEntries
(
options
);
console
.
log
(
'Logs:'
);
entries
.
forEach
(
entry
=
>
{
const
metadata
=
entry
.
metadata
;
console
.
log
(
`
${
metadata
.
timestamp
}
:`
,
metadata
[
metadata
.
payload
]);
});
}
printEntryMetadata
();
getEntries(callback)
getEntries
(
callback
:
GetEntriesCallback
)
:
void
;
Returns
Type
Description
void
getEntries(options, callback)
getEntries
(
options
:
GetEntriesRequest
,
callback
:
GetEntriesCallback
)
:
void
;
Returns
Type
Description
void
getEntriesStream(options)
getEntriesStream
(
options
?:
GetEntriesRequest
)
:
Duplex
;
List the Entry objects in your logs as a readable object stream.
Logging#getEntriesStream
Parameter
Name
Description
options
GetEntriesRequest
const
{
Logging
}
=
require
(
' @google-cloud/logging
'
);
const
logging
=
new
Logging
();
logging
.
getEntriesStream
()
.
on
(
'error'
,
console
.
error
)
.
on
(
' data
'
,
entry
=
>
{
// `entry` is a Cloud Logging entry object.
// See the `data` property to read the data from the entry.
})
.
on
(
'end'
,
function
()
{
// All entries retrieved.
});
//-
// If you anticipate many results, you can end a stream early to prevent
// unnecessary processing and API requests.
//-
logging
.
getEntriesStream
()
.
on
(
' data
'
,
function
(
entry
)
{
this
.
end
();
});
getLogs(options)
getLogs
(
options
?:
GetLogsRequest
)
:
Promise<GetLogsResponse>
;
List the entries in your logs.
const
{
Logging
}
=
require
(
' @google-cloud/logging
'
);
const
logging
=
new
Logging
();
logging
.
getLogs
((
err
,
logs
)
=
>
{
// `logs` is an array of Cloud Logging log objects.
});
//-
// To control how many API requests are made and page through the results
// manually, set `autoPaginate` to `false`.
//-
function
callback
(
err
,
entries
,
nextQuery
,
apiResponse
)
{
if
(
nextQuery
)
{
// More results exist.
logging
.
getLogs
(
nextQuery
,
callback
);
}
}
logging
.
getLogs
({
autoPaginate
:
false
},
callback
);
//-
// If the callback is omitted, we'll return a Promise.
//-
logging
.
getLogs
().
then
(
data
=
>
{
const
entries
=
data
[
0
];
});
Another example:
// Imports the Google Cloud client library
const
{
Logging
}
=
require
(
' @google-cloud/logging
'
);
// Creates a client
const
logging
=
new
Logging
();
async
function
printLogNames
()
{
const
[
logs
]
=
await
logging
.
getLogs
();
console
.
log
(
'Logs:'
);
logs
.
forEach
(
log
=
>
{
console
.
log
(
log
.
name
);
});
}
printLogNames
();
getLogs(callback)
getLogs
(
callback
:
GetLogsCallback
)
:
void
;
Returns
Type
Description
void
getLogs(options, callback)
getLogs
(
options
:
GetLogsRequest
,
callback
:
GetLogsCallback
)
:
void
;
Returns
Type
Description
void
getLogsStream(options)
getLogsStream
(
options
?:
GetLogsRequest
)
:
Duplex
;
List the Log objects in your project as a readable object stream.
Logging#getLogsStream
const
{
Logging
}
=
require
(
' @google-cloud/logging
'
);
const
logging
=
new
Logging
();
logging
.
getLogsStream
()
.
on
(
'error'
,
console
.
error
)
.
on
(
' data
'
,
log
=
>
{
// `log` is a Cloud Logging log object.
})
.
on
(
'end'
,
function
()
{
// All logs retrieved.
});
//-
// If you anticipate many results, you can end a stream early to prevent
// unnecessary processing and API requests.
//-
logging
.
getLogsStream
()
.
on
(
' data
'
,
log
=
>
{
this
.
end
();
});
getSinks(options)
getSinks
(
options
?:
GetSinksRequest
)
:
Promise<GetSinksResponse>
;
Get the sinks associated with this project.
const
{
Logging
}
=
require
(
' @google-cloud/logging
'
);
const
logging
=
new
Logging
();
logging
.
getSinks
((
err
,
sinks
)
=
>
{
// sinks is an array of Sink objects.
});
//-
// If the callback is omitted, we'll return a Promise.
//-
logging
.
getSinks
().
then
(
data
=
>
{
const
sinks
=
data
[
0
];
});
Another example:
// Imports the Google Cloud client library
const
{
Logging
}
=
require
(
' @google-cloud/logging
'
);
// Creates a client
const
logging
=
new
Logging
();
async
function
printSinkMetadata
()
{
// See https://googleapis.dev/nodejs/logging/latest/Logging.html#getSinks
const
[
sinks
]
=
await
logging
.
getSinks
();
console
.
log
(
'Sinks:'
);
sinks
.
forEach
(
sink
=
>
{
console
.
log
(
sink
.
name
);
console
.
log
(
` Destination:
${
sink
.
metadata
.
destination
}
`
);
console
.
log
(
` Filter:
${
sink
.
metadata
.
filter
}
`
);
});
}
printSinkMetadata
();
getSinks(callback)
getSinks
(
callback
:
GetSinksCallback
)
:
void
;
Returns
Type
Description
void
getSinks(options, callback)
getSinks
(
options
:
GetSinksRequest
,
callback
:
GetSinksCallback
)
:
void
;
Returns
Type
Description
void
getSinksStream(options)
getSinksStream
(
options
:
GetSinksRequest
)
:
Duplex
;
Get the Sink objects associated with this project as a readable object stream.
Logging#getSinksStream
const
{
Logging
}
=
require
(
' @google-cloud/logging
'
);
const
logging
=
new
Logging
();
logging
.
getSinksStream
()
.
on
(
'error'
,
console
.
error
)
.
on
(
' data
'
,
sink
=
>
{
// `sink` is a Sink object.
})
.
on
(
'end'
,
function
()
{
// All sinks retrieved.
});
//-
// If you anticipate many results, you can end a stream early to prevent
// unnecessary processing and API requests.
//-
logging
.
getSinksStream
()
.
on
(
' data
'
,
function
(
sink
)
{
this
.
end
();
});
log(name, options)
log
(
name
:
string
,
options
?:
LogOptions
)
:
Log
;
Get a reference to a Cloud Logging log.
See Log Overview
Parameters
Name
Description
name
string
Name of the existing log.
options
LogOptions
Configuration object.
Returns
Type
Description
Log
{Log}
const
{
Logging
}
=
require
(
' @google-cloud/logging
'
);
const
logging
=
new
Logging
();
const
log
=
logging
.
log
(
'my-log'
);
logSync(name, transport, options)
logSync
(
name
:
string
,
transport
?:
Writable
,
options
?:
LogSyncOptions
)
:
LogSync
;
Get a reference to a Cloud Logging logSync.
Parameters
Name
Description
name
string
Name of the existing log.
transport
Writable
An optional write stream.
options
LogSyncOptions
An optional configuration object.
Returns
Type
Description
LogSync
{LogSync}
const
{
Logging
}
=
require
(
' @google-cloud/logging
'
);
const
logging
=
new
Logging
();
// Optional: enrich logs with additional context
await
logging
.
setProjectId
();
await
logging
.
setDetectedResource
();
// Default transport writes to process.stdout
const
log
=
logging
.
logSync
(
'my-log'
);
request(config, callback)
request<TResponse
=
any
> (
config
:
RequestConfig
,
callback
?:
RequestCallback<TResponse>
)
:
Duplex
;
Funnel all API requests through this method, to be sure we have a project ID.
Parameters
Name
Description
config
callback
Returns
Type
Description
Duplex
Type Parameter
Name
Description
TResponse
setAclForBucket_(config)
setAclForBucket_
(
config
:
CreateSinkRequest
)
:
Promise<void>
;
This method is called when creating a sink with a Bucket destination. The bucket must first grant proper ACL access to the Cloud Logging account.
The parameters are the same as what accepts.
Returns
Type
Description
Promise
<void>
setAclForDataset_(config)
setAclForDataset_
(
config
:
CreateSinkRequest
)
:
Promise<void>
;
This method is called when creating a sink with a Dataset destination. The dataset must first grant proper ACL access to the Cloud Logging account.
The parameters are the same as what accepts.
Returns
Type
Description
Promise
<void>
setAclForTopic_(config)
setAclForTopic_
(
config
:
CreateSinkRequest
)
:
Promise<void>
;
This method is called when creating a sink with a Topic destination. The topic must first grant proper ACL access to the Cloud Logging account.
The parameters are the same as what accepts.
Returns
Type
Description
Promise
<void>
setDetectedResource()
setDetectedResource
()
:
Promise<void>
;
setResource detects and sets a detectedresource object on the Logging instance. It can be invoked once to ensure ensuing LogSync entries contain resource context.
Returns
Type
Description
Promise
<void>
setProjectId(reqOpts)
setProjectId
(
reqOpts
?:
{})
:
Promise<void>
;
setProjectId detects and sets a projectId string on the Logging instance. It can be invoked once to ensure ensuing LogSync entries have a projectID.
Parameter
Name
Description
reqOpts
{}
Returns
Type
Description
Promise
<void>
sink(name)
sink
(
name
:
string
)
:
Sink
;
Get a reference to a Cloud Logging sink.
See Sink Overview
Parameter
Name
Description
name
string
Name of the existing sink.
Returns
Type
Description
Sink
{Sink}
const
{
Logging
}
=
require
(
' @google-cloud/logging
'
);
const
logging
=
new
Logging
();
const
sink
=
logging
.
sink
(
'my-sink'
);
tailEntries(options)
tailEntries
(
options
?:
TailEntriesRequest
)
:
Duplex
;
Streaming read of live logs as log entries are ingested. Until the stream is terminated, it will continue reading logs.
Logging#tailEntries
Parameter
Name
Description
options
TailEntriesRequest
Returns
Type
Description
Duplex
{DuplexStream} A duplex stream that emits TailEntriesResponses containing an array of Entry instances.
const
{
Logging
}
=
require
(
' @google-cloud/logging
'
);
const
logging
=
new
Logging
();
logging
.
tailEntries
()
.
on
(
'error'
,
console
.
error
)
.
on
(
' data
'
,
resp
=
>
{
console
.
log
(
resp
.
entries
);
console
.
log
(
resp
.
suppressionInfo
);
})
.
on
(
'end'
,
function
()
{
// All entries retrieved.
});
//-
// If you anticipate many results, you can end a stream early to prevent
// unnecessary processing and API requests.
//-
logging
.
getEntriesStream
()
.
on
(
' data
'
,
function
(
entry
)
{
this
.
end
();
});
