goctx

Get your context value faster

How to use

Replace

v := ctx.Value(key)

With

v := goctx.Value(ctx, key)

Benchmark

There will be little difference when there is only 1~2 context.WithXXX calls

With 5 context.WithXXX calls

BenchmarkValue/5/non_parallel/std-8	35313684	34.2 ns/op
BenchmarkValue/5/non_parallel/goctx-8	42801348	30.0 ns/op
BenchmarkValue/5/non_parallel/pure_map-8	16655377	72.8 ns/op
BenchmarkValue/5/parallel/std-8	168420460	7.09 ns/op
BenchmarkValue/5/parallel/goctx-8	185695462	6.35 ns/op
BenchmarkValue/5/parallel/pure_map-8	67944997	17.6 ns/op

With 20 context.WithXXX calls

BenchmarkValue/20/non_parallel/std-8	7137338	168 ns/op
BenchmarkValue/20/non_parallel/goctx-8	14623730	81.4 ns/op
BenchmarkValue/20/non_parallel/pure_map-8	5282458	235 ns/op
BenchmarkValue/20/parallel/std-8	42826857	27.9 ns/op
BenchmarkValue/20/parallel/goctx-8	79149823	15.1 ns/op
BenchmarkValue/20/parallel/pure_map-8	22206717	53.8 ns/op

As we can see from the benchmark test, the map implementation is slower than the standard one, so it is not recommended to use RegisterValueFunc to register a context value function, unless you do not want to see nested stack with Value method call (That's also the reason why RegisterValueFunc is kept even it is not fast)