# Logs

This plugin returns the CloudWatch logs of a lambda function. You can simply run `serverless logs -f hello` to test it out.

**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.

## Logs Options

The logs plugin only requires the function name you want to fetch the logs for. Other than that there are other options that you can add for extra control. Here's the full options list:

- `--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 `1000`ms.

## Examples
```
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
```
This will keep the terminal session listening for logs and display them as they happen.

```
serverless logs -f hello --filter serverless
```
This will fetch only the logs that contain the string `serverless`