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37 lines
1.8 KiB
Markdown
37 lines
1.8 KiB
Markdown
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# A more minimal logging API for Go
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Before you consider this package, please read [this blog post by the inimitable
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Dave Cheney](http://dave.cheney.net/2015/11/05/lets-talk-about-logging). I
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really appreciate what he has to say, and it largely aligns with my own
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experiences. Too many choices of levels means inconsistent logs.
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This package offers a purely abstract interface, based on these ideas but with
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a few twists. Code can depend on just this interface and have the actual
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logging implementation be injected from callers. Ideally only `main()` knows
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what logging implementation is being used.
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# Differences from Dave's ideas
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The main differences are:
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1) Dave basically proposes doing away with the notion of a logging API in favor
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of `fmt.Printf()`. I disagree, especially when you consider things like output
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locations, timestamps, file and line decorations, and structured logging. I
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restrict the API to just 2 types of logs: info and error.
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Info logs are things you want to tell the user which are not errors. Error
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logs are, well, errors. If your code receives an `error` from a subordinate
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function call and is logging that `error` *and not returning it*, use error
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logs.
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2) Verbosity-levels on info logs. This gives developers a chance to indicate
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arbitrary grades of importance for info logs, without assigning names with
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semantic meaning such as "warning", "trace", and "debug". Superficially this
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may feel very similar, but the primary difference is the lack of semantics.
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Because verbosity is a numerical value, it's safe to assume that an app running
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with higher verbosity means more (and less important) logs will be generated.
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This is a BETA grade API. I have implemented it for
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[glog](https://godoc.org/github.com/golang/glog). Until there is a significant
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2nd implementation, I don't really know how it will change.
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