Migrate to static building to remove dependency to libgit2

.github/workflows/go.yml

@@ -8,6 +8,8 @@ jobs:
     steps:
     - name: Check out code into the Go module directory
       uses: actions/checkout@v2
+      with:
+        submodules: recursive
 
     - name: Set up Go 1.15
       uses: actions/setup-go@v2
@@ -20,41 +22,35 @@ jobs:
         sudo apt-get update -y \
         && sudo apt-get install -y cmake pkg-config gcc libssh2-1-dev libssl-dev
 
-    - name: set up git2go for static mode
-      run: |
-        git clone https://github.com/libgit2/git2go
-        cd git2go/
-        git checkout release-1.1
-        git submodule update --init # get libgit2
-        make install-static
-
     - name: get dependencies
       run: |
-        go get -v -t -d ./...
+        bin/setup
 
     - name: test
       run: bin/test
+      env:
+        GO_TAGS: static
 
     - name: build linux amd64
       run: bin/build
       env:
         GOOS: linux
         GOARCH: amd64
-        BUILD_TAGS: static
+        GO_TAGS: static
 
     - name: build windows amd64
       run: bin/build
       env:
         GOOS: windows
         GOARCH: amd64
-        BUILD_TAGS: static
+        GO_TAGS: static
 
     - name: build darwin amd64
       run: bin/build
       env:
         GOOS: darwin
         GOARCH: amd64
-        BUILD_TAGS: static
+        GO_TAGS: static
 
     - name: package software for linux amd64
       run: bin/package

README.md

@@ -77,6 +77,42 @@ lg build -V
 After building letters, you will find a directory called `letters` in the
 current directory.
 
+## Development
+
+### Build letter-generator from its sources
+
+~~~
+bin/setup
+bin/build
+bin/test
+~~~
+
+### Central configuration file for helper scripts
+
+Configuration for helper scripts is done via environment variables in [`env.sh`](env.sh).
+
+### Upgrade git2go / libgit2
+
+See https://github.com/libgit2/git2go#master-branch-or-vendored-static-linking
+for more information about this. 
+
+If you plan to upgrade your version, you need to modify a few files.
+
+1. Update version for "libgit2" in `env.sh`
+
+  ~~~bash
+: ${LIBGIT2_TAG:=release-1.1}
+  ~~~
+
+2. Update version of "git2go" in `go.mod`
+
+  ~~~bash
+  # [...]
+  github.com/libgit2/git2go/v31 v31.4.7
+  # [...]
+  replace github.com/libgit2/git2go/v31 => ./ext_deps/git2go
+  ~~~
+
 ## Copyright
 
 (c) 2021, Dennis Günnewig

bin/build

@@ -1,13 +1,8 @@
 #!/usr/bin/env bash
 
-: ${GOOS:=linux}
-: ${GOARCH:=amd64}
-: ${GO_TAGS:=static,system_libgit2}
+source ./env.sh
 
-COMMIT_HASH=$(git rev-parse --short HEAD 2>/dev/null)
-BUILD_DATE=$(date +%FT%T%z)
-VERSION=$(git tag | sort | tail -n 1)
-VERSION=${VERSION/v/};
+echo --- Build letter-generator
 
 echo GO111MODULE=on CGO_ENABLED=1 go build --tags ${GO_TAGS} $* -ldflags "-w -s -X main.AppVersionNumber=${VERSION} -X main.CommitHash=${COMMIT_HASH} -X main.BuildDate=${BUILD_DATE}" -o dist/${GOOS}/${GOARCH}/lg ./cmd/lg
 GO111MODULE=on CGO_ENABLED=1 go build --tags ${GO_TAGS} $* -ldflags "-w -s -X main.AppVersionNumber=${VERSION} -X main.CommitHash=${COMMIT_HASH} -X main.BuildDate=${BUILD_DATE}" -o dist/${GOOS}/${GOARCH}/lg ./cmd/lg

bin/setup

@@ -1,5 +1,17 @@
 #!/bin/bash
 
-echo install libgit2
+source ./env.sh
 
+echo --- Build static git2go
+
+git submodule update --init # get git2go
+cd ext_deps/git2go
+git checkout ${LIBGIT2_TAG}
+git submodule update --init # get libgit2
+make install-static
+cd -
+
+echo
+echo --- Install dependencies
+echo go get -d -v ./...
 go get -d -v ./...

bin/test

@@ -1,5 +1,6 @@
-#!/usr/bin/env sh
+#!/usr/bin/env bash
 
-: ${GO_TAGS:=static,system_libgit2}
+source ./env.sh
 
+echo --- Test letter-generator
 go test --tags ${GO_TAGS} -v ./... $*

env.sh

@@ -0,0 +1,9 @@
+: ${GOOS:=linux}
+: ${GOARCH:=amd64}
+: ${GO_TAGS:=static}
+: ${LIBGIT2_TAG:=release-1.1}
+
+: ${COMMIT_HASH:=$(git rev-parse --short HEAD 2>/dev/null)}
+: ${BUILD_DATE:=$(date +%FT%T%z)}
+: ${VERSION:=$(git tag | sort | tail -n 1)}
+: ${VERSION:=${VERSION/v/}}

go.mod

@@ -2,8 +2,6 @@ module github.com/feduxorg/letter-generator
 
 go 1.12
 
-//replace github.com/libgit2/git2go => github.com/maxmeyer/git2go v0.28.4
-
 require (
 	github.com/cpuguy83/go-md2man/v2 v2.0.0 // indirect
 	github.com/libgit2/git2go/v31 v31.4.7
@@ -17,3 +15,5 @@ require (
 	golang.org/x/sys v0.0.0-20210113181707-4bcb84eeeb78 // indirect
 	gopkg.in/yaml.v2 v2.4.0
 )
+
+replace github.com/libgit2/git2go/v31 => ./ext_deps/git2go

go.sum

@@ -43,6 +43,7 @@ github.com/urfave/cli v1.22.2/go.mod h1:Gos4lmkARVdJ6EkW0WaNv/tZAAMe9V7XWyB60NtX
 github.com/urfave/cli v1.22.5 h1:lNq9sAHXK2qfdI8W+GRItjCEkI+2oR4d+MEHy1CKXoU=
 github.com/urfave/cli v1.22.5/go.mod h1:Gos4lmkARVdJ6EkW0WaNv/tZAAMe9V7XWyB60NtXRu0=
 golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
+golang.org/x/crypto v0.0.0-20200728195943-123391ffb6de/go.mod h1:LzIPMQfyMNhhGPhUkYOs5KpL4U8rLKemX1yGLhDgUto=
 golang.org/x/crypto v0.0.0-20201203163018-be400aefbc4c h1:9HhBz5L/UjnK9XLtiZhYAdue5BVKep3PMmS2LuPDt8k=
 golang.org/x/crypto v0.0.0-20201203163018-be400aefbc4c/go.mod h1:jdWPYTVW3xRLrWPugEBEK3UY2ZEsg3UU495nc5E+M+I=
 golang.org/x/crypto v0.0.0-20201221181555-eec23a3978ad h1:DN0cp81fZ3njFcrLCytUHRSUkqBjfTo4Tx9RJTWs0EY=
@@ -54,6 +55,7 @@ golang.org/x/net v0.0.0-20191209160850-c0dbc17a3553/go.mod h1:z5CRVTTTmAJ677TzLL
 golang.org/x/net v0.0.0-20201224014010-6772e930b67b h1:iFwSg7t5GZmB/Q5TjiEAsdoLDrdJRC1RiF2WhuV29Qw=
 golang.org/x/net v0.0.0-20201224014010-6772e930b67b/go.mod h1:m0MpNAwzfU5UDzcl9v0D8zg8gWTRqZa9RBIspLL5mdg=
 golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
+golang.org/x/sys v0.0.0-20190412213103-97732733099d/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20190422165155-953cdadca894 h1:Cz4ceDQGXuKRnVBDTS23GTn/pU5OE2C0WrNTOYK1Uuc=
 golang.org/x/sys v0.0.0-20190422165155-953cdadca894/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20191026070338-33540a1f6037 h1:YyJpGZS1sBuBCzLAR1VEpK193GlqGZbnPFnPV/5Rsb4=