Encapsulates golang runtime in docker container.
Minimal runtime depedencies: listed versions reflect development environment at the time of latest commit
- GNU Make, 4.3
~ $ make -v
GNU Make 4.3
Built for x86_64-apple-darwin17.7.0
Copyright (C) 1988-2020 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.
- Bash, 5.0.18
~ $ bash --version
GNU bash, version 5.0.18(1)-release (x86_64-apple-darwin17.7.0)
Copyright (C) 2019 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>
This is free software; you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.
- Docker, 19.03.13
~ $ docker version
Client: Docker Engine - Community
Cloud integration 0.1.18
Version: 19.03.13
API version: 1.40
Go version: go1.13.15
Git commit: 4484c46d9d
Built: Wed Sep 16 16:58:31 2020
OS/Arch: darwin/amd64
Experimental: false
Server: Docker Engine - Community
Engine:
Version: 19.03.13
API version: 1.40 (minimum version 1.12)
Go version: go1.13.15
Git commit: 4484c46d9d
Built: Wed Sep 16 17:07:04 2020
OS/Arch: linux/amd64
Experimental: false
containerd:
Version: v1.3.7
GitCommit: 8fba4e9a7d01810a393d5d25a3621dc101981175
runc:
Version: 1.0.0-rc10
GitCommit: dc9208a3303feef5b3839f4323d9beb36df0a9dd
docker-init:
Version: 0.18.0
GitCommit: fec3683
Ephemeral installation of golang wrapper, into current shell session.
1. Clone repository.
$ path=/tmp/go
$ git clone [email protected]:callowaylc/go $path
Cloning into '/tmp/go'...
remote: Enumerating objects: 11, done.
remote: Counting objects: 100% (11/11), done.
remote: Compressing objects: 100% (8/8), done.
remote: Total 11 (delta 0), reused 11 (delta 0), pack-reused 0
Receiving objects: 100% (11/11), done.
2. Create build target.
$ pushd $path
/tmp/go ~ ~/Develop/highlight/go ~
$ make
mkdir -p "dist" "dist"/src
...
3. Install into current shell session.
$ which go
/usr/local/bin/go
$ file /usr/local/bin/go
/usr/local/bin/go: Mach-O 64-bit executable x86_64
$ make install
$ which go
/tmp/go/dist/go
$ file /tmp/go/dist/go
/tmp/go/dist/go: POSIX shell script text executable, ASCII text
Please review official documentation for golang command line tool. https://golang.org/cmd/go/
$ go help
Go is a tool for managing Go source code.
Usage:
go <command> [arguments]
Descriptions for notable repository files and concepts.
- Makefile: A prefabbed interface to the repository
- env: Runtime environment configuration
- env/base: Baseline configuration available to all invocations of tool
- src/main.sh: The golang runtime/docker wrapper
Exporting environment variables ("envs") to the runtime must be explicitly declared in GOENV environment configuration files.
Envs are declared (and optionally defined) in dotenv style (and shell compliant) files, that declare (and optionally define) name/value pairs.
$ $ cat env/base
#!/usr/bin/false
## Adds key, value pairs as environment variables to go cmd runtime
## https://golang.org/cmd/go/#hdr-Environment_variables
## https://docs.docker.com/engine/reference/commandline/run/#set-environment-variables--e---env---env-file
# Declare variable and assign nil value
GOOS=
GOARCH=
# Declare variable and use value exported to local
# environment, if any
HELLO
# Declare variable and assign value
FRANKIE=heart
List envs available to golang runtime by running example/envs.go
.
$ which go
/Users/christian/Develop/highlight/go/dist/go
$ go run example/envs.go
HOSTNAME=> 893ac30c4dc8
PATH => /go/bin:/usr/local/go/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin
HOSTNAME => 893ac30c4dc8
FRANKIE => heart
GOARCH =>
GOOS =>
DOCKER => true
CONTAINER => true
GOLANG_VERSION => 1.15.7
GOPATH => /go
HOME => /root
Repeat with inline (re-)definition of HELLO
.
# Variable `HELLO` is declared but not bound to defined value.
$ cat env/base | grep -i hello
HELLO
# Assign "world" to variable `HELLO`, both inline and within current scope
$ HELLO=world go run example/envs.go | grep -i hello
HELLO => world
$ HELLO=bye go run example/envs.go | grep -i hello
HELLO => bye
Repeat with inline declaration of variable FUBAR
.
# Variable `FUBAR` is not declared in existing configuration.
$ ls -1 env
base
build
run
$ cat env/* | grep -i -- fubar
$ echo $?
1
# Variable `FUBAR` is not availabe in runtime.
$ FUBAR=rabug HELLO=world2 go run example/envs.go | grep -Ei -- 'hello|fubar'
HELLO => world2
Declare FUBAR
in dist/env/base
to make available to the runtime.
$ echo FUBAR=rabuf | tee -a dist/env/base
FUBAR=rabuf
# Check runtime envs again
$ go run example/envs.go | grep -i -- fubar
FUBAR => rabuf
$ echo $?
0
Environment configuration can be split into multiple files, that can be overlaid (atop one another) and presented as a single composite to the runtime. Merge direction follows an established convention, allowing us to strategize precedence, relative to the action being taken. Operators should limit use/reliance on configuration overlays, given that there isn't an official analogue and that it's raison d'etre is to compensate for differences (os, arch, etc) between host and golang runtime.
The wrapper workflow defines an additional file descriptor, /dev/fd/3 which receives logger messages and debug payloads.
- By default, STDLOG writes are against /dev/null.
$ go run example/exitwith.go 3
exit status 3
- Redirecting
&3
to STDERR will reveal "STDLOG" payloads
$ go run example/exitwith.go 0 3>&2
Jan 15 00:18:19 /Users/christian/Develop/highlight/go/dist/go#15496[15502] <Debug>: Main -- cnVuIGV4YW1wbGUvZXhpdHdpdGguZ28gMAo=
docker run --rm --env CONTAINER=true --env DOCKER=true --volume /Users/christian/Develop/highlight/go:/opt/main:rw --workdir /opt/main --env "GOOS=" --env "GOARCH=" golang:1.15 go run example/exitwith.go 0
Jan 15 00:18:20 /Users/christian/Develop/highlight/go/dist/go#15496[15515] <Debug>: Teardown -- trace=/Users/christian/Develop/highlight/go/dist/go pid=15496 status=0