// Copyright (C) The Arvados Authors. All rights reserved. // // SPDX-License-Identifier: Apache-2.0 // Package service provides a cmd.Handler that brings up a system service. package service import ( "context" "flag" "fmt" "io" "net" "net/http" _ "net/http/pprof" "net/url" "os" "strings" "git.arvados.org/arvados.git/lib/cmd" "git.arvados.org/arvados.git/lib/config" "git.arvados.org/arvados.git/sdk/go/arvados" "git.arvados.org/arvados.git/sdk/go/ctxlog" "git.arvados.org/arvados.git/sdk/go/health" "git.arvados.org/arvados.git/sdk/go/httpserver" "github.com/coreos/go-systemd/daemon" "github.com/julienschmidt/httprouter" "github.com/prometheus/client_golang/prometheus" "github.com/sirupsen/logrus" ) type Handler interface { http.Handler CheckHealth() error // Done returns a channel that closes when the handler shuts // itself down, or nil if this never happens. Done() <-chan struct{} } type NewHandlerFunc func(_ context.Context, _ *arvados.Cluster, token string, registry *prometheus.Registry) Handler type command struct { newHandler NewHandlerFunc svcName arvados.ServiceName ctx context.Context // enables tests to shutdown service; no public API yet } // Command returns a cmd.Handler that loads site config, calls // newHandler with the current cluster and node configs, and brings up // an http server with the returned handler. // // The handler is wrapped with server middleware (adding X-Request-ID // headers, logging requests/responses, etc). func Command(svcName arvados.ServiceName, newHandler NewHandlerFunc) cmd.Handler { return &command{ newHandler: newHandler, svcName: svcName, ctx: context.Background(), } } func (c *command) RunCommand(prog string, args []string, stdin io.Reader, stdout, stderr io.Writer) int { log := ctxlog.New(stderr, "json", "info") var err error defer func() { if err != nil { log.WithError(err).Error("exiting") } }() flags := flag.NewFlagSet("", flag.ContinueOnError) flags.SetOutput(stderr) loader := config.NewLoader(stdin, log) loader.SetupFlags(flags) // prog is [keepstore, keep-web, git-httpd, ...] but the // legacy config flags are [-legacy-keepstore-config, // -legacy-keepweb-config, -legacy-git-httpd-config, ...] legacyFlag := "-legacy-" + strings.Replace(prog, "keep-", "keep", 1) + "-config" args = loader.MungeLegacyConfigArgs(log, args, legacyFlag) versionFlag := flags.Bool("version", false, "Write version information to stdout and exit 0") pprofAddr := flags.String("pprof", "", "Serve Go profile data at `[addr]:port`") if ok, code := cmd.ParseFlags(flags, prog, args, "", stderr); !ok { return code } else if *versionFlag { return cmd.Version.RunCommand(prog, args, stdin, stdout, stderr) } if *pprofAddr != "" { go func() { log.Println(http.ListenAndServe(*pprofAddr, nil)) }() } if strings.HasSuffix(prog, "controller") { // Some config-loader checks try to make API calls via // controller. Those can't be expected to work if this // process _is_ the controller: we haven't started an // http server yet. loader.SkipAPICalls = true } cfg, err := loader.Load() if err != nil { return 1 } cluster, err := cfg.GetCluster("") if err != nil { return 1 } // Now that we've read the config, replace the bootstrap // logger with a new one according to the logging config. log = ctxlog.New(stderr, cluster.SystemLogs.Format, cluster.SystemLogs.LogLevel) logger := log.WithFields(logrus.Fields{ "PID": os.Getpid(), "ClusterID": cluster.ClusterID, }) ctx := ctxlog.Context(c.ctx, logger) listenURL, err := getListenAddr(cluster.Services, c.svcName, log) if err != nil { return 1 } ctx = context.WithValue(ctx, contextKeyURL{}, listenURL) reg := prometheus.NewRegistry() loader.RegisterMetrics(reg) // arvados_version_running{version="1.2.3~4"} 1.0 mVersion := prometheus.NewGaugeVec(prometheus.GaugeOpts{ Namespace: "arvados", Name: "version_running", Help: "Indicated version is running.", }, []string{"version"}) mVersion.WithLabelValues(cmd.Version.String()).Set(1) reg.MustRegister(mVersion) handler := c.newHandler(ctx, cluster, cluster.SystemRootToken, reg) if err = handler.CheckHealth(); err != nil { return 1 } instrumented := httpserver.Instrument(reg, log, httpserver.HandlerWithDeadline(cluster.API.RequestTimeout.Duration(), httpserver.AddRequestIDs( httpserver.LogRequests( interceptHealthReqs(cluster.ManagementToken, handler.CheckHealth, httpserver.NewRequestLimiter(cluster.API.MaxConcurrentRequests, handler, reg)))))) srv := &httpserver.Server{ Server: http.Server{ Handler: ifCollectionInHost(instrumented, instrumented.ServeAPI(cluster.ManagementToken, instrumented)), BaseContext: func(net.Listener) context.Context { return ctx }, }, Addr: listenURL.Host, } if listenURL.Scheme == "https" { tlsconfig, err := tlsConfigWithCertUpdater(cluster, logger) if err != nil { logger.WithError(err).Errorf("cannot start %s service on %s", c.svcName, listenURL.String()) return 1 } srv.TLSConfig = tlsconfig } err = srv.Start() if err != nil { return 1 } logger.WithFields(logrus.Fields{ "URL": listenURL, "Listen": srv.Addr, "Service": c.svcName, "Version": cmd.Version.String(), }).Info("listening") if _, err := daemon.SdNotify(false, "READY=1"); err != nil { logger.WithError(err).Errorf("error notifying init daemon") } go func() { // Shut down server if caller cancels context <-ctx.Done() srv.Close() }() go func() { // Shut down server if handler dies <-handler.Done() srv.Close() }() err = srv.Wait() if err != nil { return 1 } return 0 } // If an incoming request's target vhost has an embedded collection // UUID or PDH, handle it with hTrue, otherwise handle it with // hFalse. // // Facilitates routing "http://collections.example/metrics" to metrics // and "http://{uuid}.collections.example/metrics" to a file in a // collection. func ifCollectionInHost(hTrue, hFalse http.Handler) http.Handler { return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) { if arvados.CollectionIDFromDNSName(r.Host) != "" { hTrue.ServeHTTP(w, r) } else { hFalse.ServeHTTP(w, r) } }) } func interceptHealthReqs(mgtToken string, checkHealth func() error, next http.Handler) http.Handler { mux := httprouter.New() mux.Handler("GET", "/_health/ping", &health.Handler{ Token: mgtToken, Prefix: "/_health/", Routes: health.Routes{"ping": checkHealth}, }) mux.NotFound = next return ifCollectionInHost(next, mux) } func getListenAddr(svcs arvados.Services, prog arvados.ServiceName, log logrus.FieldLogger) (arvados.URL, error) { svc, ok := svcs.Map()[prog] if !ok { return arvados.URL{}, fmt.Errorf("unknown service name %q", prog) } if want := os.Getenv("ARVADOS_SERVICE_INTERNAL_URL"); want == "" { } else if url, err := url.Parse(want); err != nil { return arvados.URL{}, fmt.Errorf("$ARVADOS_SERVICE_INTERNAL_URL (%q): %s", want, err) } else { if url.Path == "" { url.Path = "/" } return arvados.URL(*url), nil } errors := []string{} for url := range svc.InternalURLs { listener, err := net.Listen("tcp", url.Host) if err == nil { listener.Close() return url, nil } else if strings.Contains(err.Error(), "cannot assign requested address") { // If 'Host' specifies a different server than // the current one, it'll resolve the hostname // to IP address, and then fail because it // can't bind an IP address it doesn't own. continue } else { errors = append(errors, fmt.Sprintf("tried %v, got %v", url, err)) } } if len(errors) > 0 { return arvados.URL{}, fmt.Errorf("could not enable the %q service on this host: %s", prog, strings.Join(errors, "; ")) } return arvados.URL{}, fmt.Errorf("configuration does not enable the %q service on this host", prog) } type contextKeyURL struct{} func URLFromContext(ctx context.Context) (arvados.URL, bool) { u, ok := ctx.Value(contextKeyURL{}).(arvados.URL) return u, ok }