https://github.com/blendle/go-logger

Shared logging library for Go-based applications.
https://github.com/blendle/go-logger

Last synced: 2 days ago
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Shared logging library for Go-based applications.

• Host: GitHub
• URL: https://github.com/blendle/go-logger
• Owner: blendle
• License: isc
• Created: 2017-06-25T20:45:35.000Z (over 7 years ago)
• Default Branch: master
• Last Pushed: 2018-06-09T17:41:43.000Z (over 6 years ago)
• Last Synced: 2023-09-03T17:32:36.754Z (over 1 year ago)
• Language: Go
• Size: 60.5 KB
• Stars: 2
• Watchers: 9
• Forks: 1
• Open Issues: 0
• Metadata Files:
  • Readme: README.md
  • License: LICENSE

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README

        
# go-logger

This package contains shared logic for Go-based structured logging.

This package uses the [`zap`][zap] logging package under the hood. See its

[README][zap] for more details on the logging API.

[zap]: https://github.com/uber-go/zap#zap-zap---

## Usage

Add to your `main.go`:

```golang

import logger "github.com/blendle/go-logger"

func main() {

  logger := logger.Must(logger.New("my-service", "cf89f839"))

}

```

Then use it throughout your application:

```golang

logger.Warn("Something happened!")

```

### Custom Zap Options

You can also provide custom Zap options on initialization, if you need it:

```golang

sampler := zap.WrapCore(func(core zapcore.Core) zapcore.Core {

  return zapcore.NewSampler(core, time.Second, 100, 100)

})

fields := zap.Fields(zap.String("alwaysAdd", "this"))

logger := logger.Must(logger.New("my-service", "cf89f839", sampler, fields))

```

### Stackdriver logging

You can optionally add Stackdriver specific fields to your logs. These can be

used by Stackdriver to [improve log readability/grouping][sd].

```golang

import zapdriver "github.com/blendle/zapdriver"

```

```golang

logger.Info("Hello", zapdriver.Label("hello", "world"))

```

See [here][zd] for all available Stackdriver fields.

[sd]: https://cloud.google.com/error-reporting/docs/formatting-error-messages

[zd]: https://github.com/blendle/zapdriver#special-purpose-logging-fields

## Debugging

You can send the `USR1` signal to your application to switch the log level

between the default `INFO` and `DEBUG` level on runtime.

This allows you to capture debug logs during anomalies and find the problem.

You can also set the `DEBUG` environment variable to `true` to have the

application launch with the default log level set to `DEBUG` instead of `INFO`.

Again, you can send `USR1` to toggle back to `INFO` as well.

## Testing

This package contains a public testing API you can use if you need to assert

a log entry exists.

```golang

// TestNew calls New, but returns both the logger, and an observer that can be

// used to fetch and compare delivered logs.

TestNew(tb testing.TB, options ...zap.Option) (*zap.Logger, *observer.ObservedLogs)

```

```golang

// TestNewWithLevel is equal to TestNew, except that it takes an extra argument,

// dictating the minimum log level required to record an entry in the recorder.

TestNewWithLevel(tb testing.TB, level zapcore.LevelEnabler, options ...zap.Option) (*zap.Logger, *observer.ObservedLogs)

```

see `testing.go` for more details.