feat: response server version in response header (#61)

Author: bcho

Makefile

@@ -1,3 +1,5 @@
+SHELL = bash
+
 all: help
 
 ##@ General
@@ -24,12 +26,15 @@ fmt: ## Run go fmt against code.
 vet: ## Run go vet against code.
 	go vet ./...
 
-run-server: fmt vet ## Run server.
-	echo "test" > local_dev.token
-	go run . serve --db-dsn ./test.sqlite3?_journal_mode=WAL --http-addr 127.0.0.1:8080 --metrics-addr 127.0.0.1:8081 --pprof-addr 127.0.0.1:8082 --log-devel --log-level 12 --auth-token-file local_dev.token
+build-server: fmt vet ## Build server.
+	go build .
+
+run-server: build-server ## Run server.
+	echo -n "test" > local_dev.token
+	./sqlite-rest serve --db-dsn ./test.sqlite3?_journal_mode=WAL --http-addr 127.0.0.1:8080 --metrics-addr 127.0.0.1:8081 --pprof-addr 127.0.0.1:8082 --log-devel --log-level 12 --auth-token-file local_dev.token --security-allow-table fruit
 
-run-migrate: fmt vet ## Run migration.
-	go run . migrate --db-dsn ./test.sqlite3?_journal_mode=WAL --log-devel --log-level 12 ./data
+run-migrate: build-server ## Run migration.
+	./sqlite-rest migrate --db-dsn ./test.sqlite3?_journal_mode=WAL --log-devel --log-level 12 ./data
 
 ##@ Build
 

fs.go

@@ -9,7 +9,7 @@ func readFileWithStatCache(file string) func() ([]byte, error) {
 	mu := new(sync.RWMutex)
 	var (
 		lastReadContent []byte
-		lastStat os.FileInfo
+		lastStat        os.FileInfo
 	)
 
 	fast := func() (bool, []byte, error) {

server.go

@@ -83,6 +83,8 @@ func NewServer(opts *ServerOptions) (*dbServer, error) {
 		logger: opts.Logger.WithName("db-server"),
 		server: &http.Server{
 			Addr: opts.Addr,
+			// TODO: make it configurable
+			ReadHeaderTimeout: 5 * time.Second,
 		},
 		queryer: opts.Queryer,
 		execer:  opts.Execer,
@@ -137,6 +139,11 @@ func (server *dbServer) Start(done <-chan struct{}) {
 	server.server.Shutdown(shutdownCtx)
 }
 
+func (server *dbServer) responseHeader(w http.ResponseWriter, statusCode int) {
+	w.Header().Set("Server", ServerVersion)
+	w.WriteHeader(statusCode)
+}
+
 func (server *dbServer) responseError(w http.ResponseWriter, err error) {
 	var serverError *ServerError
 	switch {
@@ -149,7 +156,7 @@ func (server *dbServer) responseError(w http.ResponseWriter, err error) {
 }
 
 func (server *dbServer) responseData(w http.ResponseWriter, data interface{}, statusCode int) {
-	w.WriteHeader(statusCode)
+	server.responseHeader(w, statusCode)
 
 	enc := json.NewEncoder(w)
 	if encodeErr := enc.Encode(data); encodeErr != nil {
@@ -160,7 +167,7 @@ func (server *dbServer) responseData(w http.ResponseWriter, data interface{}, st
 }
 
 func (server *dbServer) responseEmptyBody(w http.ResponseWriter, statusCode int) {
-	w.WriteHeader(statusCode)
+	server.responseHeader(w, statusCode)
 }
 
 func (server *dbServer) handleQueryTableOrView(

version.go

@@ -0,0 +1,57 @@
+package main
+
+import (
+	"fmt"
+	"runtime/debug"
+)
+
+// ServerVersion defines the server application version.
+// Use -ldflags "-X main.ServerVersion=1.0.0" to override the version.
+var ServerVersion string
+
+func loadServerVersionFromBuildInfo() string {
+	info, ok := debug.ReadBuildInfo()
+	if !ok {
+		return ""
+	}
+
+	var (
+		commit string = "unknown"
+		dirty  bool
+	)
+	for _, s := range info.Settings {
+		switch {
+		case s.Key == "vcs.revision":
+			commit = s.Value
+			if len(s.Value) > 10 {
+				commit = commit[:10]
+			}
+		case s.Key == "vcs.modified":
+			dirty = s.Value == "true"
+		}
+	}
+	if dirty {
+		commit += "-dirty"
+	}
+
+	s := fmt.Sprintf("sqlite-rest/%s (%s, commit/%s)", info.Main.Version, info.GoVersion, commit)
+
+	return s
+}
+
+func setServerVersion() {
+	if ServerVersion != "" {
+		return
+	}
+
+	if v := loadServerVersionFromBuildInfo(); v != "" {
+		ServerVersion = v
+		return
+	}
+
+	ServerVersion = "(devel)"
+}
+
+func init() {
+	setServerVersion()
+}