Add extended version info

This change introduces a pair of CLI options - `-version` and `-version-json` - to
print the verions of scylla-bench and gocql driver, in human-readable or JSON
formats respectively.

Closes: #156

Author: dimakr

Makefile

@@ -1,6 +1,11 @@
 GOCQL_REPO?=github.com/scylladb/gocql
 DOCKER_IMAGE_TAG?=scylla-bench
 
+VERSION ?= $(shell git describe --tags 2>/dev/null || echo "dev")
+COMMIT ?= $(shell git rev-parse HEAD 2>/dev/null || echo "unknown")
+BUILD_DATE ?= $(shell git log -1 --format=%cd --date=format:%Y-%m-%dT%H:%M:%SZ 2>/dev/null || date -u +"%Y-%m-%dT%H:%M:%SZ")
+LDFLAGS_VERSION := -X github.com/scylladb/scylla-bench/internal/version.version=$(VERSION) -X github.com/scylladb/scylla-bench/internal/version.commit=$(COMMIT) -X github.com/scylladb/scylla-bench/internal/version.date=$(BUILD_DATE)
+
 _prepare_build_dir:
 	@mkdir build >/dev/null 2>&1 || true
 
@@ -12,16 +17,16 @@ _use-custom-gocql-version:
   	fi;\
   	echo "Using custom gocql commit \"${GOCQL_VERSION}\"";\
 	go mod edit -replace "github.com/gocql/gocql=${GOCQL_REPO}@${GOCQL_VERSION}";\
-	go mod tidy;\
+	go mod tidy -compat=1.17;\
 	}
 
 build: _prepare_build_dir
 	@echo "Building static scylla-bench"
-	@CGO_ENABLED=0 go build -ldflags="-s -w" -o ./build/scylla-bench .
+	@CGO_ENABLED=0 go build -ldflags="-s -w $(LDFLAGS_VERSION)" -o ./build/scylla-bench .
 
 build-debug: _prepare_build_dir
 	@echo "Building debug version of static scylla-bench"
-	@CGO_ENABLED=0 go build -gcflags "all=-N -l" -o ./build/scylla-bench .
+	@CGO_ENABLED=0 go build -gcflags "all=-N -l" -ldflags="$(LDFLAGS_VERSION)" -o ./build/scylla-bench .
 
 .PHONY: build-with-custom-gocql-version
 build-with-custom-gocql-version: _use-custom-gocql-version build

internal/version/version.go

@@ -0,0 +1,357 @@
+package version
+
+import (
+	"encoding/json"
+	"fmt"
+	"net/http"
+	"os"
+	"os/exec"
+	"regexp"
+	"runtime/debug"
+	"strings"
+	"time"
+)
+
+const (
+	gocqlPackage     = "github.com/gocql/gocql"
+	githubTimeout    = 5 * time.Second
+	userAgent        = "scylla-bench (github.com/scylladb/scylla-bench)"
+	githubAPIBaseURL = "https://api.github.com"
+)
+
+// Default version values; can be overridden via ldflags
+var (
+	version = "dev"
+	commit  = "unknown"
+	date    = "unknown"
+)
+
+type ComponentInfo struct {
+	Version    string `json:"version"`
+	CommitDate string `json:"commit_date"`
+	CommitSHA  string `json:"commit_sha"`
+}
+
+type VersionInfo struct {
+	ScyllaBench ComponentInfo `json:"scylla-bench"`
+	Driver      ComponentInfo `json:"scylla-driver"`
+}
+
+type githubRelease struct {
+	TagName   string    `json:"tag_name"`
+	CreatedAt time.Time `json:"created_at"`
+}
+
+type githubTag struct {
+	Object struct {
+		SHA string `json:"sha"`
+	} `json:"object"`
+}
+
+type githubClient struct {
+	client    *http.Client
+	baseURL   string
+	userAgent string
+}
+
+func newGithubClient() *githubClient {
+	return &githubClient{
+		client:    &http.Client{Timeout: githubTimeout},
+		baseURL:   githubAPIBaseURL,
+		userAgent: userAgent,
+	}
+}
+
+// Performs an HTTP GET request and decodes the JSON response to the target
+func (g *githubClient) getJSON(path string, target interface{}) error {
+	url := g.baseURL + path
+	req, err := http.NewRequest("GET", url, nil)
+	if err != nil {
+		return fmt.Errorf("failed to create request: %w", err)
+	}
+	req.Header.Set("User-Agent", g.userAgent)
+
+	resp, err := g.client.Do(req)
+	if err != nil {
+		return fmt.Errorf("request failed: %w", err)
+	}
+	defer resp.Body.Close()
+
+	if resp.StatusCode != http.StatusOK {
+		return fmt.Errorf("unexpected status %d", resp.StatusCode)
+	}
+
+	if err := json.NewDecoder(resp.Body).Decode(target); err != nil {
+		return fmt.Errorf("failed to decode JSON: %w", err)
+	}
+	return nil
+}
+
+// Fetches release date and commit SHA for the given version
+func (g *githubClient) getReleaseInfo(owner, repo, version string) (date, sha string, err error) {
+	// Fetch releases
+	path := fmt.Sprintf("/repos/%s/%s/releases", owner, repo)
+	var releases []githubRelease
+	if err := g.getJSON(path, &releases); err != nil {
+		return "", "", fmt.Errorf("failed to fetch releases: %w", err)
+	}
+
+	// Find matching release
+	cleanVersion := strings.TrimPrefix(version, "v")
+	var releaseDate, tagName string
+	for _, release := range releases {
+		if strings.TrimPrefix(release.TagName, "v") == cleanVersion {
+			releaseDate, tagName = release.CreatedAt.Format(time.RFC3339), release.TagName
+			break
+		}
+	}
+	if tagName == "" {
+		return "", "", fmt.Errorf("release %s not found", version)
+	}
+
+	// Fetch tag info to get the commit SHA
+	tagPath := fmt.Sprintf("/repos/%s/%s/git/refs/tags/%s", owner, repo, tagName)
+	var tag githubTag
+	if err := g.getJSON(tagPath, &tag); err != nil {
+		return releaseDate, "", fmt.Errorf("failed to fetch tag info: %w", err)
+	}
+
+	return releaseDate, tag.Object.SHA, nil
+}
+
+// Fetches information about the given commit
+func (g *githubClient) getCommitInfo(owner, repo, sha string) (date string, err error) {
+	path := fmt.Sprintf("/repos/%s/%s/commits/%s", owner, repo, sha)
+	var commit struct {
+		Commit struct {
+			Committer struct {
+				Date string `json:"date"`
+			} `json:"committer"`
+		} `json:"commit"`
+	}
+
+	if err := g.getJSON(path, &commit); err != nil {
+		return "", fmt.Errorf("failed to fetch commit info: %w", err)
+	}
+
+	return commit.Commit.Committer.Date, nil
+}
+
+func tryGitCommand(args ...string) (string, bool) {
+	output, err := exec.Command("git", args...).Output()
+	if err != nil {
+		return "", false
+	}
+	return strings.TrimSpace(string(output)), true
+}
+
+// Reads version info from local Git repository
+func getGitVersionInfo() (ver, sha, buildDate string, ok bool) {
+	// Check if git is available and we're in a git repo
+	if _, ok := tryGitCommand("rev-parse", "--is-inside-work-tree"); !ok {
+		return "", "", "", false
+	}
+
+	// Get released version details
+	sha, ok = tryGitCommand("rev-parse", "HEAD")
+	if !ok {
+		return "", "", "", false
+	}
+	buildDate, ok = tryGitCommand("log", "-1", "--format=%cd", "--date=format:%Y-%m-%dT%H:%M:%SZ")
+	if !ok {
+		return "", "", "", false
+	}
+	if tags, ok := tryGitCommand("tag", "--points-at", "HEAD"); ok && tags != "" {
+		for _, tag := range strings.Split(tags, "\n") {
+			if strings.HasPrefix(tag, "v") {
+				return tag, sha, buildDate, true
+			}
+		}
+	}
+
+	// If not a released version, use the most recent tag to build a dev version string
+	if closestTag, ok := tryGitCommand("describe", "--tags", "--abbrev=0"); ok && strings.HasPrefix(closestTag, "v") {
+		return fmt.Sprintf("%s-dev-%s", closestTag, sha[:8]), sha, buildDate, true
+	}
+
+	return fmt.Sprintf("dev-%s", sha[:8]), sha, buildDate, true
+}
+
+func isCommitSHA(s string) bool {
+	shaPattern := regexp.MustCompile(`^[0-9a-fA-F]{7,40}$`)
+	return shaPattern.MatchString(s)
+}
+
+func extractCommitSHA(version string) string {
+	if isCommitSHA(version) {
+		return version
+	}
+
+	// If version is in pseudo-version format (e.g v0.0.0-20230101120000-abcdef123456)
+	if strings.Count(version, "-") >= 2 {
+		parts := strings.Split(version, "-")
+		candidate := parts[len(parts)-1]
+		if isCommitSHA(candidate) {
+			return candidate
+		}
+	}
+
+	return ""
+}
+
+func extractRepoOwner(repoPath string, defaultOwner string) string {
+	parts := strings.Split(repoPath, "/")
+	if len(parts) >= 2 {
+		return parts[1]
+	}
+	return defaultOwner
+}
+
+// Extracts driver version info
+func getDriverVersionInfo() ComponentInfo {
+	info := ComponentInfo{
+		Version:    "unknown",
+		CommitSHA:  "unknown",
+		CommitDate: "unknown",
+	}
+
+	// Get driver module from build info
+	buildInfo, ok := debug.ReadBuildInfo()
+	if !ok {
+		return info
+	}
+	var driverModule *debug.Module
+	for _, dep := range buildInfo.Deps {
+		if dep.Path == gocqlPackage {
+			driverModule = dep
+			break
+		}
+	}
+	if driverModule == nil {
+		return info
+	}
+
+	github := newGithubClient()
+	if replacement := driverModule.Replace; replacement != nil {
+		// If custom version is set via GOCQL_VERSION env var
+		if envSHA := os.Getenv("GOCQL_VERSION"); envSHA != "" && isCommitSHA(envSHA) {
+			info.Version = envSHA
+			info.CommitSHA = envSHA
+
+			repoOwner := extractRepoOwner(os.Getenv("GOCQL_REPO"), "scylladb")
+			if date, err := github.getCommitInfo(repoOwner, "gocql", envSHA); err == nil {
+				info.CommitDate = date
+			}
+			return info
+		}
+
+		// Otherwise try to extract released version (e.g. v1.2.3)
+		if strings.HasPrefix(replacement.Version, "v") && !strings.Contains(replacement.Version, "-") {
+			info.Version = replacement.Version
+			if date, sha, err := github.getReleaseInfo("scylladb", "gocql", replacement.Version); err == nil {
+				info.CommitDate = date
+				info.CommitSHA = sha
+			}
+			return info
+		}
+
+		// Otherwise handle pseudo-versions or direct SHA
+		version := replacement.Version
+		if sha := extractCommitSHA(version); sha != "" {
+			info.Version = sha
+			info.CommitSHA = sha
+
+			repoOwner := extractRepoOwner(replacement.Path, "scylladb")
+			if date, err := github.getCommitInfo(repoOwner, "gocql", sha); err == nil {
+				info.CommitDate = date
+			}
+			return info
+		}
+
+		// As a fallback, just use what we have as a version
+		info.Version = version
+		return info
+	}
+
+	// If no driver module replacement, this is the upstream gocql driver
+	info.Version = driverModule.Version
+	info.CommitSHA = "upstream release"
+	return info
+}
+
+// Extracts scylla-bench version info
+func getMainBuildInfo() (ver, sha, buildDate string) {
+	ver, sha, buildDate = version, commit, date
+
+	// Use git info if no version was provided via ldflags
+	if ver == "dev" {
+		if gitVer, gitSha, gitDate, ok := getGitVersionInfo(); ok {
+			return gitVer, gitSha, gitDate
+		}
+	}
+
+	// Otherwise fall back to go build info
+	if info, ok := debug.ReadBuildInfo(); ok {
+		if ver == "dev" {
+			if info.Main.Version != "" {
+				ver = info.Main.Version
+			} else {
+				ver = "(devel)"
+			}
+		}
+
+		for _, setting := range info.Settings {
+			switch setting.Key {
+			case "vcs.revision":
+				if sha == "unknown" {
+					sha = setting.Value
+				}
+			case "vcs.time":
+				if buildDate == "unknown" {
+					buildDate = setting.Value
+				}
+			}
+		}
+	}
+	return
+}
+
+// GetVersionInfo returns the version info for scylla-bench and scylla-gocql-driver
+func GetVersionInfo() VersionInfo {
+	ver, sha, buildDate := getMainBuildInfo()
+	return VersionInfo{
+		ScyllaBench: ComponentInfo{
+			Version:    ver,
+			CommitDate: buildDate,
+			CommitSHA:  sha,
+		},
+		Driver: getDriverVersionInfo(),
+	}
+}
+
+// FormatHuman returns a human-readable string with version info
+func (v VersionInfo) FormatHuman() string {
+	return fmt.Sprintf(`scylla-bench:
+    version: %s
+    commit sha: %s
+    commit date: %s
+scylla-gocql-driver:
+    version: %s
+    commit sha: %s
+    commit date: %s`,
+		v.ScyllaBench.Version,
+		v.ScyllaBench.CommitSHA,
+		v.ScyllaBench.CommitDate,
+		v.Driver.Version,
+		v.Driver.CommitSHA,
+		v.Driver.CommitDate)
+}
+
+// FormatJSON returns a JSON-formatted string with version info
+func (v VersionInfo) FormatJSON() (string, error) {
+	data, err := json.MarshalIndent(v, "", "  ")
+	if err != nil {
+		return "", fmt.Errorf("failed to marshal version info to JSON: %w", err)
+	}
+	return string(data), nil
+}