Function Name

[sourabhxyz]

Is there a way to modify configuration or some tweak in caller configuration so that I can as well have a function name along with filename and line. Currently I had written my own code to do it using runtime.

Thanks

[prashantv]

This doesn't exist today, zap can only add file:line. I think adding the function could be a useful option though.

[prashantv]

We'll be happy to accept a PR implementing this, thanks!

[wijayaerick]

I'd like to implement this. This is my first time contributing to open source repo, so please bear with me.

Several API changes I think of:

1. Add Function string field on zapcore.Entry
2. Add FunctionKey string field on zapcore.EncoderConfig. With both changes in zapcore.Entry and zapcore.EncoderConfig, we can modify encoders EncodeEntry in console/json encoder to include the Function.

type Entry struct {
	...
	Caller     EntryCaller
	Function   string
	Stack      string
}

type EncoderConfig struct {
	...
	CallerKey     string `json:"callerKey" yaml:"callerKey"`
	FunctionKey   string `json:"functionKey" yaml:"functionKey"`
	StacktraceKey string `json:"stacktraceKey" yaml:"stacktraceKey"`
	...
}

3. Changes in zap.Logger

We can introduce WithFunction(bool) Option and private field Logger.addFunction. This way, we can just add new condition on Logger.check(..). We have AddCallerSkip(int) Option to skip callers; I'm thinking that we want to reuse this to skip functions (instead of introducing AddFunctionSkip(int) Option, because we'll never want to skip them differently (if we skip caller by 2, we want to also skip function by 2).

4. FunctionEncoder

I can't think about how we want to encode function names other than the name given by runtime. So, I think we won't need FunctionEncoder.

Would love to hear your opinion on this, thanks!
@prashantv