serverless/docs/providers/aws/cli-reference/logs.md

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AWS - Logs

Lets you watch the logs of a specific function.

serverless logs -f hello

# Optionally tail the logs with -t
serverless logs -f hello -t

Options

• --function or -f The function you want to fetch the logs for. Required
• --stage or -s The stage you want to view the function logs for. If not provided, the plugin will use the default stage listed in serverless.yml. If that doesn't exist either it'll just fetch the logs from the dev stage.
• --region or -r The region you want to view the function logs for. If not provided, the plugin will use the default region listed in serverless.yml. If that doesn't exist either it'll just fetch the logs from the us-east-1 region.
• --startTime A specific unit in time to start fetching logs from (ie: 2010-10-20 or 1469705761). Here's a list of the supported string formats:

30m                   # since 30 minutes ago
2h                    # since 2 hours ago
3d                    # since 3 days ago

2013-02-08            # A calendar date part
2013-W06-5            # A week date part
2013-039              # An ordinal date part

20130208              # Basic (short) full date
2013W065              # Basic (short) week, weekday
2013W06               # Basic (short) week only
2013050               # Basic (short) ordinal date

2013-02-08T09         # An hour time part separated by a T
20130208T080910,123   # Short date and time up to ms, separated by comma
20130208T080910.123   # Short date and time up to ms
20130208T080910       # Short date and time up to seconds
20130208T0809         # Short date and time up to minutes
20130208T08           # Short date and time, hours only

• --filter You can specify a filter string to filter the log output. This is useful if you want to to get the error logs for example.
• --tail or -t You can optionally tail the logs and keep listening for new logs in your terminal session by passing this option.
• --interval or -i If you choose to tail the output, you can control the interval at which the framework polls the logs with this option. The default is 1000ms.

Examples

AWS

Note: There's a small lag between invoking the function and actually having the log event registered in CloudWatch. So it takes a few seconds for the logs to show up right after invoking the function.

serverless logs -f hello --startTime 5h

This will fetch the logs that happened in the past 5 hours.

serverless logs -f hello --startTime 1469694264

This will fetch the logs that happened starting at epoch 1469694264.

serverless logs -f hello -t

Serverless will tail the CloudWatch log output and print new log messages coming in.

serverless logs -f hello --filter serverless

This will fetch only the logs that contain the string serverless