Support goreleaser (#35)

I'm hoping this will help with release automation. Obviously, I've no
way of really testing it until I commit it, so fingers crossed...

.github/workflows/release.yml

@@ -0,0 +1,31 @@
+---
+name: Release
+
+on:
+  push:
+    tags:
+      - 'v*'
+
+permissions:
+  contents: write
+
+jobs:
+
+  goreleaser:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+        with:
+          fetch-depth: 0
+
+      - name: Set up Go
+        uses: actions/setup-go@v4
+
+      - name: Run GoReleaser
+        uses: goreleaser/goreleaser-action@v4
+        with:
+          distribution: goreleaser
+          version: latest
+          args: release --clean
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}

.gitignore

@@ -5,3 +5,5 @@
 *~
 /.vscode/
 *.code-workspace
+
+dist/

.goreleaser.yaml

@@ -0,0 +1,54 @@
+before:
+  hooks:
+    - go mod tidy
+builds:
+  - env:
+      - CGO_ENABLED=0
+    goos:
+      - linux
+      - windows
+      - darwin
+      - freebsd
+    goarch:
+      - amd64
+      - arm64
+    ignore:
+      - goos: windows
+        goarch: arm
+    main: ./cmd/mercury
+    flags:
+      - -trimpath
+    ldflags:
+      - -s -w -X github.com/kgaughan/mercury/internal/version.Version={{.Version}}
+    tags:
+      - netgo
+
+archives:
+  - format: tar.xz
+    name_template: >-
+      {{ .ProjectName }}_
+      {{- title .Os }}_
+      {{- if eq .Arch "amd64" }}x86_64
+      {{- else if eq .Arch "386" }}i386
+      {{- else }}{{ .Arch }}{{ end }}
+      {{- if .Arm }}v{{ .Arm }}{{ end }}
+    # use zip for windows archives
+    format_overrides:
+      - goos: windows
+        format: zip
+    files:
+      - LICENSE
+      - README.md
+      - theme/*
+checksum:
+  name_template: "checksums.txt"
+snapshot:
+  name_template: "{{ incpatch .Version }}-next"
+changelog:
+  sort: asc
+  filters:
+    exclude:
+      - "^docs:"
+      - "^test:"
+# yaml-language-server: $schema=https://goreleaser.com/static/schema.json
+# vim: set ts=2 sw=2 tw=0 fo=cnqoj

Makefile

@@ -1,16 +1,14 @@
-VERSION:=$(shell git describe --tags --always | sed s/^v//)
-
 SOURCE:=$(wildcard internal/*.go internal/*/*.go cmd/mercury/*.go)
 
 build: go.mod mercury
 
 tidy: go.mod
 
 clean:
-	rm -f mercury
+	rm -rf mercury dist
 
 mercury: $(SOURCE) go.sum
-	CGO_ENABLED=0 go build -trimpath -ldflags '-s -w -X github.com/kgaughan/mercury/internal/version.Version=$(VERSION)' -o mercury ./cmd/mercury
+	CGO_ENABLED=0 go build -tags netgo -trimpath -ldflags '-s -w' -o mercury ./cmd/mercury
 
 update:
 	go get -u ./...

internal/version/version.go

@@ -2,7 +2,7 @@ package version
 
 import "fmt"
 
-// Version contains the version (set during build).
+// nolint: gochecknoglobals
 var Version string
 
 const repo = "https://github.com/kgaughan/mercury/"

todo.md

@@ -1,7 +1,5 @@
 # TODO
 
 - [ ] If a cache miss causes an item to be fetched, keep the feed in memory rather than loading the copy saved to disc.
-- [ ] Ensure fetched feeds are sorted from newest to oldest item. Could this be done lazily with container/heap? This would be more complicated than using the sort package, but would have the advantage of bubbling up only the required items in the feed.
 - [ ] Is there a good way to expose further feed/entry information in the template?
-- [ ] Themes should include a BOM indicating which files should be copied across to the output directory.
 - [ ] Give a way to specify particular categories that should be included from the source feed. This would be useful for blogs that lack per-category feeds.