build: improve debian packaging

This commit tweaks the debian packaging tool:

* All build environment metadata can now be overriden on the command
  line. This allows testing the CI build behaviour locally.
* -unstable packages now actually contain the binaries (oops)
* packages use Go 1.7 to build
* archiving is skipped for PR builds

1 files changed, 86 insertions, 103 deletions

diff --git a/build/ci.go b/build/ci.go
index 87e8b6275..cf43969f6 100644
--- a/build/ci.go
+++ b/build/ci.go
@@ -120,8 +120,6 @@ func main() {
 		doArchive(os.Args[2:])
 	case "debsrc":
 		doDebianSource(os.Args[2:])
-	case "travis-debsrc":
-		doTravisDebianSource(os.Args[2:])
 	case "xgo":
 		doXgo(os.Args[2:])
 	default:
@@ -132,8 +130,8 @@ func main() {
 // Compiling
 
 func doInstall(cmdline []string) {
-	commitHash := flag.String("gitcommit", "", "Git commit hash embedded into binary.")
 	flag.CommandLine.Parse(cmdline)
+	env := build.Env()
 
 	// Check Go version. People regularly open issues about compilation
 	// failure with outdated Go. This should save them the trouble.
@@ -150,13 +148,17 @@ func doInstall(cmdline []string) {
 		packages = flag.Args()
 	}
 
-	goinstall := goTool("install", makeBuildFlags(*commitHash)...)
+	goinstall := goTool("install", buildFlags(env)...)
 	goinstall.Args = append(goinstall.Args, "-v")
 	goinstall.Args = append(goinstall.Args, packages...)
 	build.MustRun(goinstall)
 }
 
-func makeBuildFlags(commitHash string) (flags []string) {
+func buildFlags(env build.Environment) (flags []string) {
+	if os.Getenv("GO_OPENCL") != "" {
+		flags = append(flags, "-tags", "opencl")
+	}
+
 	// Since Go 1.5, the separator char for link time assignments
 	// is '=' and using ' ' prints a warning. However, Go < 1.5 does
 	// not support using '='.
@@ -164,26 +166,9 @@ func makeBuildFlags(commitHash string) (flags []string) {
 	if runtime.Version() > "go1.5" || strings.Contains(runtime.Version(), "devel") {
 		sep = "="
 	}
-
-	if os.Getenv("GO_OPENCL") != "" {
-		flags = append(flags, "-tags", "opencl")
-	}
-
-	// Set gitCommit constant via link-time assignment. If this is a git checkout, we can
-	// just get the current commit hash through git. Otherwise we fall back to the hash
-	// that was passed as -gitcommit.
-	//
-	// -gitcommit is required for Debian package builds. The source package doesn't
-	// contain .git but we still want to embed the commit hash into the packaged binary.
-	// The hash is rendered into the debian/rules build script when the source package is
-	// created.
-	if _, err := os.Stat(filepath.Join(".git", "HEAD")); !os.IsNotExist(err) {
-		if c := build.GitCommit(); c != "" {
-			commitHash = c
-		}
-	}
-	if commitHash != "" {
-		flags = append(flags, "-ldflags", "-X main.gitCommit"+sep+commitHash)
+	// Set gitCommit constant via link-time assignment.
+	if env.Commit != "" {
+		flags = append(flags, "-ldflags", "-X main.gitCommit"+sep+env.Commit)
 	}
 	return flags
 }
@@ -253,7 +238,11 @@ func doArchive(cmdline []string) {
 	default:
 		log.Fatal("unknown archive type: ", atype)
 	}
-	base := makeArchiveBasename()
+
+	env := build.Env()
+	maybeSkipArchive(env)
+
+	base := archiveBasename(env)
 	if err := build.WriteArchive("geth-"+base, ext, gethArchiveFiles); err != nil {
 		log.Fatal(err)
 	}
@@ -262,36 +251,41 @@ func doArchive(cmdline []string) {
 	}
 }
 
-func makeArchiveBasename() string {
+func archiveBasename(env build.Environment) string {
 	// date := time.Now().UTC().Format("200601021504")
 	platform := runtime.GOOS + "-" + runtime.GOARCH
 	archive := platform + "-" + build.VERSION()
-	if commit := build.GitCommit(); commit != "" {
-		archive += "-" + commit[:8]
+	if env.Commit != "" {
+		archive += "-" + env.Commit[:8]
 	}
 	return archive
 }
 
+// skips archiving for some build configurations.
+func maybeSkipArchive(env build.Environment) {
+	if env.IsPullRequest {
+		log.Printf("skipping because this is a PR build")
+		os.Exit(0)
+	}
+	if env.Branch != "develop" && !strings.HasPrefix(env.Tag, "v1.") {
+		log.Printf("skipping because branch %q, tag %q is not on the whitelist", env.Branch, env.Tag)
+		os.Exit(0)
+	}
+}
+
 // Debian Packaging
 
-// CLI entry point for Travis CI.
-func doTravisDebianSource(cmdline []string) {
+func doDebianSource(cmdline []string) {
+	var (
+		signer  = flag.String("signer", "", `Signing key name, also used as package author`)
+		upload  = flag.String("upload", "", `Where to upload the source package (usually "ppa:ethereum/ethereum")`)
+		workdir = flag.String("workdir", "", `Output directory for packages (uses temp dir if unset)`)
+		now     = time.Now()
+	)
 	flag.CommandLine.Parse(cmdline)
-
-	// Package only whitelisted branches.
-	switch {
-	case os.Getenv("TRAVIS_REPO_SLUG") != "ethereum/go-ethereum":
-		log.Printf("skipping because this is a fork build")
-		return
-	case os.Getenv("TRAVIS_PULL_REQUEST") != "false":
-		log.Printf("skipping because this is a PR build")
-		return
-	case os.Getenv("TRAVIS_BRANCH") != "develop" && !strings.HasPrefix(os.Getenv("TRAVIS_TAG"), "v1."):
-		log.Printf("skipping because branch %q tag %q is not on the whitelist",
-			os.Getenv("TRAVIS_BRANCH"),
-			os.Getenv("TRAVIS_TAG"))
-		return
-	}
+	*workdir = makeWorkdir(*workdir)
+	env := build.Env()
+	maybeSkipArchive(env)
 
 	// Import the signing key.
 	if b64key := os.Getenv("PPA_SIGNING_KEY"); b64key != "" {
@@ -304,46 +298,16 @@ func doTravisDebianSource(cmdline []string) {
 		build.MustRun(gpg)
 	}
 
-	// Assign unstable status to non-tag builds.
-	unstable := "true"
-	if os.Getenv("TRAVIS_BRANCH") != "develop" && os.Getenv("TRAVIS_TAG") != "" {
-		unstable = "false"
-	}
-
-	doDebianSource([]string{
-		"-signer", "Felix Lange (Geth CI Testing Key) <fjl@twurst.com>",
-		"-buildnum", os.Getenv("TRAVIS_BUILD_NUMBER"),
-		"-upload", "ppa:lp-fjl/geth-ci-testing",
-		"-unstable", unstable,
-	})
-}
-
-// CLI entry point for doing packaging locally.
-func doDebianSource(cmdline []string) {
-	var (
-		signer   = flag.String("signer", "", `Signing key name, also used as package author`)
-		upload   = flag.String("upload", "", `Where to upload the source package (usually "ppa:ethereum/ethereum")`)
-		buildnum = flag.String("buildnum", "", `Build number (included in version)`)
-		unstable = flag.Bool("unstable", false, `Use package name suffix "-unstable"`)
-		now      = time.Now()
-	)
-	flag.CommandLine.Parse(cmdline)
-
-	// Create the debian worktree in /tmp.
-	tmpdir, err := ioutil.TempDir("", "eth-deb-build-")
-	if err != nil {
-		log.Fatal(err)
-	}
-
+	// Create the packages.
 	for _, distro := range debDistros {
-		meta := newDebMetadata(distro, *signer, *buildnum, *unstable, now)
-		pkgdir := stageDebianSource(tmpdir, meta)
+		meta := newDebMetadata(distro, *signer, env, now)
+		pkgdir := stageDebianSource(*workdir, meta)
 		debuild := exec.Command("debuild", "-S", "-sa", "-us", "-uc")
 		debuild.Dir = pkgdir
 		build.MustRun(debuild)
 
 		changes := fmt.Sprintf("%s_%s_source.changes", meta.Name(), meta.VersionString())
-		changes = filepath.Join(tmpdir, changes)
+		changes = filepath.Join(*workdir, changes)
 		if *signer != "" {
 			build.MustRunCommand("debsign", changes)
 		}
@@ -353,35 +317,53 @@ func doDebianSource(cmdline []string) {
 	}
 }
 
-type debExecutable struct {
-	Name, Description string
+func makeWorkdir(wdflag string) string {
+	var err error
+	if wdflag != "" {
+		err = os.MkdirAll(wdflag, 0744)
+	} else {
+		wdflag, err = ioutil.TempDir("", "eth-deb-build-")
+	}
+	if err != nil {
+		log.Fatal(err)
+	}
+	return wdflag
+}
+
+func isUnstableBuild(env build.Environment) bool {
+	if env.Branch != "develop" && env.Tag != "" {
+		return false
+	}
+	return true
 }
 
 type debMetadata struct {
+	Env build.Environment
+
 	// go-ethereum version being built. Note that this
 	// is not the debian package version. The package version
 	// is constructed by VersionString.
 	Version string
 
-	Author               string // "name <email>", also selects signing key
-	Buildnum             string // build number
-	Distro, Commit, Time string
-	Executables          []debExecutable
-	Unstable             bool
+	Author       string // "name <email>", also selects signing key
+	Distro, Time string
+	Executables  []debExecutable
 }
 
-func newDebMetadata(distro, author, buildnum string, unstable bool, t time.Time) debMetadata {
+type debExecutable struct {
+	Name, Description string
+}
+
+func newDebMetadata(distro, author string, env build.Environment, t time.Time) debMetadata {
 	if author == "" {
 		// No signing key, use default author.
 		author = "Ethereum Builds <fjl@ethereum.org>"
 	}
 	return debMetadata{
-		Unstable:    unstable,
+		Env:         env,
 		Author:      author,
 		Distro:      distro,
-		Commit:      build.GitCommit(),
 		Version:     build.VERSION(),
-		Buildnum:    buildnum,
 		Time:        t.Format(time.RFC1123Z),
 		Executables: debExecutables,
 	}
@@ -390,7 +372,7 @@ func newDebMetadata(distro, author, buildnum string, unstable bool, t time.Time)
 // Name returns the name of the metapackage that depends
 // on all executable packages.
 func (meta debMetadata) Name() string {
-	if meta.Unstable {
+	if isUnstableBuild(meta.Env) {
 		return "ethereum-unstable"
 	}
 	return "ethereum"
@@ -399,8 +381,8 @@ func (meta debMetadata) Name() string {
 // VersionString returns the debian version of the packages.
 func (meta debMetadata) VersionString() string {
 	vsn := meta.Version
-	if meta.Buildnum != "" {
-		vsn += "+build" + meta.Buildnum
+	if meta.Env.Buildnum != "" {
+		vsn += "+build" + meta.Env.Buildnum
 	}
 	if meta.Distro != "" {
 		vsn += "+" + meta.Distro
@@ -419,7 +401,7 @@ func (meta debMetadata) ExeList() string {
 
 // ExeName returns the package name of an executable package.
 func (meta debMetadata) ExeName(exe debExecutable) string {
-	if meta.Unstable {
+	if isUnstableBuild(meta.Env) {
 		return exe.Name + "-unstable"
 	}
 	return exe.Name
@@ -428,7 +410,7 @@ func (meta debMetadata) ExeName(exe debExecutable) string {
 // ExeConflicts returns the content of the Conflicts field
 // for executable packages.
 func (meta debMetadata) ExeConflicts(exe debExecutable) string {
-	if meta.Unstable {
+	if isUnstableBuild(meta.Env) {
 		// Set up the conflicts list so that the *-unstable packages
 		// cannot be installed alongside the regular version.
 		//
@@ -461,8 +443,8 @@ func stageDebianSource(tmpdir string, meta debMetadata) (pkgdir string) {
 	build.RenderString("8\n", filepath.Join(debian, "compat"), 0644, meta)
 	build.RenderString("3.0 (native)\n", filepath.Join(debian, "source/format"), 0644, meta)
 	for _, exe := range meta.Executables {
-		install := filepath.Join(debian, exe.Name+".install")
-		docs := filepath.Join(debian, exe.Name+".docs")
+		install := filepath.Join(debian, meta.ExeName(exe)+".install")
+		docs := filepath.Join(debian, meta.ExeName(exe)+".docs")
 		build.Render("build/deb.install", install, 0644, exe)
 		build.Render("build/deb.docs", docs, 0644, exe)
 	}
@@ -473,18 +455,19 @@ func stageDebianSource(tmpdir string, meta debMetadata) (pkgdir string) {
 // Cross compilation
 
 func doXgo(cmdline []string) {
+	flag.CommandLine.Parse(cmdline)
+	env := build.Env()
+
 	// Make sure xgo is available for cross compilation
 	gogetxgo := goTool("get", "github.com/karalabe/xgo")
 	build.MustRun(gogetxgo)
 
 	// Execute the actual cross compilation
-	pkg := cmdline[len(cmdline)-1]
-	args := append(cmdline[:len(cmdline)-1], makeBuildFlags("")...)
-
-	build.MustRun(xgoTool(append(args, pkg)...))
+	xgo := xgoTool(append(buildFlags(env), flag.Args()...))
+	build.MustRun(xgo)
 }
 
-func xgoTool(args ...string) *exec.Cmd {
+func xgoTool(args []string) *exec.Cmd {
 	cmd := exec.Command(filepath.Join(GOBIN, "xgo"), args...)
 	cmd.Env = []string{
 		"GOPATH=" + build.GOPATH(),