delputnam / buildconstants

Generate a Go file with the output of compile time shell commands

##buildconstants

for putting build info (and other compile-time values) in Go constants

Sometimes it can be useful to include constants that were available at compile-time, the build number, git branch, etc. This utility will generate a go file with constants that are the output of various commands.

The goal is to be able to include this in a go generate comment so the file will be automatically created as necessary.

It does include a constant MustRunBuildConstants so that the file with the go generate statement can be used to force a useful compiler error

##Example of using with go generate

example.go:

//go:generate buildconstants

// this will generate a compiler error to remind you to run it
var _ = MustRunBuildConstants 

##Example: Given a text file with shell commands, like so:

GOVERSION = go version
BUILD_NUMBER = ${BUILD_NUMBER}

Running go generate before building will evaluate the commands and variables in the shell.

This will be used to generate something like:

package currentPackage

const (
    GOVERSION = "go version go1.6.2 linux/amd64"
)

Which then allows you to use currentPackage.GOVERSION in your code.

##Arguments

-o output file name (defaults to buildconstants_generated.go)
-package the package the file will be in (defaults to current package)
-i input file of commands 

##License

MIT