ugorji__go/FAQ.md

FAQ

Managing Binary Size

This package adds some size to any binary that depends on it. This is because we include an auto-generated file: fast-path.generated.go to help with performance when encoding/decoding slices and maps of built in numeric, boolean, string and interface{} types.

Prior to 2019-05-16, this package could add about 11MB to the size of your binaries. We have now trimmed that in half, and the package contributes about 5.5MB. This compares favorably to other packages like json-iterator/go (3.3MB) and net/http (3.5MB).

Furthermore, you can bypass building fast-path.generated.go, by building (or running tests and benchmarks) with the tag: notfastpath.

go install -tags notfastpath
go build -tags notfastpath
go test -tags notfastpath

With the tag notfastpath, we trim that size to about 2.8MB.

Be aware that, at least in our representative microbenchmarks for cbor (for example), passing notfastpath tag causes significant performance loss (about 33%).
YMMV.

Resolving Module Issues

Prior to v1.1.5, go-codec unknowingly introduced some headaches for its users while introducing module support. We tried to make github.com/ugorji/go/codec a module. At that time, multi-repository module support was weak, so we reverted and made github.com/ugorji/go/ the module. However, folks previously used go-codec in module mode before it formally supported modules. Eventually, different established packages had go.mod files contain various real and pseudo versions of go-codec which causes go to barf with ambiguous import error.

To resolve this, from v1.1.5 and up, we use a requirements cycle between modules github.com/ugorji/go/codec and github.com/ugorji/go/, tagging them with parallel consistent tags (codec/vX.Y.Z and vX.Y.Z) to the same commit.

Fixing ambiguous import failure is now as simple as running

go get -u github.com/ugorji/go/codec@latest