implement systemd socket activation

License: MIT
Signed-off-by: Steven Allen <steven@stebalien.com>

cmd/ipfs/daemon.go

@@ -15,6 +15,7 @@ import (
 	version "github.com/ipfs/go-ipfs"
 	config "github.com/ipfs/go-ipfs-config"
 	cserial "github.com/ipfs/go-ipfs-config/serialize"
+	sockets "github.com/ipfs/go-ipfs/cmd/ipfs/sockets"
 	utilmain "github.com/ipfs/go-ipfs/cmd/ipfs/util"
 	oldcmds "github.com/ipfs/go-ipfs/commands"
 	"github.com/ipfs/go-ipfs/core"
@@ -290,11 +291,6 @@ func daemonFunc(req *cmds.Request, re cmds.ResponseEmitter, env cmds.Environment
 	// fail before we get to that. It can't hurt to close it twice.
 	defer repo.Close()
 
-	cfg, err := cctx.GetConfig()
-	if err != nil {
-		return err
-	}
-
 	offline, _ := req.Options[offlineKwd].(bool)
 	ipnsps, _ := req.Options[enableIPNSPubSubKwd].(bool)
 	pubsub, _ := req.Options[enablePubSubKwd].(bool)
@@ -404,15 +400,11 @@ func daemonFunc(req *cmds.Request, re cmds.ResponseEmitter, env cmds.Environment
 		return err
 	}
 
-	// construct http gateway - if it is set in the config
-	var gwErrc <-chan error
-	if len(cfg.Addresses.Gateway) > 0 {
-		var err error
-		gwErrc, err = serveHTTPGateway(req, cctx)
+	// construct http gateway
+	gwErrc, err := serveHTTPGateway(req, cctx)
 	if err != nil {
 		return err
 	}
-	}
 
 	// initialize metrics collector
 	prometheus.MustRegister(&corehttp.IpfsNodeCollector{Node: node})
@@ -446,6 +438,12 @@ func serveHTTPApi(req *cmds.Request, cctx *oldcmds.Context) (<-chan error, error
 		return nil, fmt.Errorf("serveHTTPApi: GetConfig() failed: %s", err)
 	}
 
+	listeners, err := sockets.TakeSockets("io.ipfs.api")
+	if err != nil {
+		return nil, fmt.Errorf("serveHTTPGateway: socket activation failed: %s", err)
+	}
+
+	if len(listeners) == 0 {
 		apiAddrs := make([]string, 0, 2)
 		apiAddr, _ := req.Options[commands.ApiOption].(string)
 		if apiAddr == "" {
@@ -466,12 +464,15 @@ func serveHTTPApi(req *cmds.Request, cctx *oldcmds.Context) (<-chan error, error
 				return nil, fmt.Errorf("serveHTTPApi: manet.Listen(%s) failed: %s", apiMaddr, err)
 			}
 
-		// we might have listened to /tcp/0 - lets see what we are listing on
-		apiMaddr = apiLis.Multiaddr()
-		fmt.Printf("API server listening on %s\n", apiMaddr)
-		fmt.Printf("WebUI: http://%s/webui\n", apiLis.Addr())
 			listeners = append(listeners, apiLis)
 		}
+	}
+
+	for _, listener := range listeners {
+		// we might have listened to /tcp/0 - lets see what we are listing on
+		fmt.Printf("API server listening on %s\n", listener.Multiaddr())
+		fmt.Printf("WebUI: http://%s/webui\n", listener.Addr())
+	}
 
 	// by default, we don't let you load arbitrary ipfs objects through the api,
 	// because this would open up the api to scripting vulnerabilities.
@@ -571,8 +572,13 @@ func serveHTTPGateway(req *cmds.Request, cctx *oldcmds.Context) (<-chan error, e
 		writable = cfg.Gateway.Writable
 	}
 
+	listeners, err := sockets.TakeSockets("io.ipfs.gateway")
+	if err != nil {
+		return nil, fmt.Errorf("serveHTTPGateway: socket activation failed: %s", err)
+	}
+
+	if len(listeners) == 0 {
 		gatewayAddrs := cfg.Addresses.Gateway
-	listeners := make([]manet.Listener, 0, len(gatewayAddrs))
 		for _, addr := range gatewayAddrs {
 			gatewayMaddr, err := ma.NewMultiaddr(addr)
 			if err != nil {
@@ -583,16 +589,18 @@ func serveHTTPGateway(req *cmds.Request, cctx *oldcmds.Context) (<-chan error, e
 			if err != nil {
 				return nil, fmt.Errorf("serveHTTPGateway: manet.Listen(%s) failed: %s", gatewayMaddr, err)
 			}
-		// we might have listened to /tcp/0 - lets see what we are listing on
-		gatewayMaddr = gwLis.Multiaddr()
+			listeners = append(listeners, gwLis)
+		}
+	}
 
+	// we might have listened to /tcp/0 - lets see what we are listing on
+	gwType := "readonly"
 	if writable {
-			fmt.Printf("Gateway (writable) server listening on %s\n", gatewayMaddr)
-		} else {
-			fmt.Printf("Gateway (readonly) server listening on %s\n", gatewayMaddr)
+		gwType = "writable"
 	}
 
-		listeners = append(listeners, gwLis)
+	for _, listener := range listeners {
+		fmt.Printf("Gateway (%s) server listening on %s\n", gwType, listener.Multiaddr())
 	}
 
 	cmdctx := *cctx

cmd/ipfs/sockets/sockets.go

+// +build !linux
+
+package sockets
+
+import (
+	manet "github.com/multiformats/go-multiaddr-net"
+)
+
+// TakeSockets takes the sockets associated with the given name.
+func TakeSockets(name string) ([]manet.Listener, error) {
+	return nil, nil
+}

cmd/ipfs/sockets/sockets_linux.go

+// +build linux
+
+package sockets
+
+import (
+	"net"
+	"sync"
+
+	activation "github.com/coreos/go-systemd/activation"
+	logging "github.com/ipfs/go-log"
+	manet "github.com/multiformats/go-multiaddr-net"
+)
+
+var log = logging.Logger("socket-activation")
+
+var socketsMu sync.Mutex
+var sockets map[string][]manet.Listener
+
+func initSockets() {
+	if sockets != nil {
+		return
+	}
+	nlisteners, err := activation.ListenersWithNames()
+	// Do this before checking the error. We need this to be non-nil so we
+	// don't try again.
+	sockets = make(map[string][]manet.Listener, len(nlisteners))
+	if err != nil {
+		log.Errorf("error parsing systemd sockets: %s", err)
+		return
+	}
+	for name, nls := range nlisteners {
+		mls := make([]manet.Listener, 0, len(nls))
+		for _, nl := range nls {
+			ml, err := manet.WrapNetListener(nl)
+			if err != nil {
+				log.Errorf("error converting a systemd-socket to a multiaddr listener: %s", err)
+				nl.Close()
+				continue
+			}
+			mls = append(mls, ml)
+		}
+		sockets[name] = mls
+	}
+}
+
+func mapListeners(nls []net.Listener) ([]manet.Listener, error) {
+	mls := make([]manet.Listener, len(nls))
+	return mls, nil
+}
+
+// TakeSockets takes the sockets associated with the given name.
+func TakeSockets(name string) ([]manet.Listener, error) {
+	socketsMu.Lock()
+	defer socketsMu.Unlock()
+	initSockets()
+
+	s := sockets[name]
+	delete(sockets, name)
+
+	return s, nil
+}

go.mod

@@ -5,6 +5,7 @@ require (
 	github.com/AndreasBriese/bbloom v0.0.0-20190823232136-616930265c33 // indirect
 	github.com/blang/semver v3.5.1+incompatible
 	github.com/bren2010/proquint v0.0.0-20160323162903-38337c27106d
+	github.com/coreos/go-systemd v0.0.0-20190719114852-fd7a80b32e1f
 	github.com/dustin/go-humanize v1.0.0
 	github.com/elgris/jsondiff v0.0.0-20160530203242-765b5c24c302
 	github.com/fatih/color v1.7.0 // indirect

go.sum

@@ -51,6 +51,8 @@ github.com/coreos/go-semver v0.2.0/go.mod h1:nnelYz7RCh+5ahJtPPxZlU+153eP4D4r3Ee
 github.com/coreos/go-semver v0.2.1-0.20180108230905-e214231b295a/go.mod h1:nnelYz7RCh+5ahJtPPxZlU+153eP4D4r3EedlOD2RNk=
 github.com/coreos/go-semver v0.3.0 h1:wkHLiw0WNATZnSG7epLsujiMCgPAc9xhjJ4tgnAxmfM=
 github.com/coreos/go-semver v0.3.0/go.mod h1:nnelYz7RCh+5ahJtPPxZlU+153eP4D4r3EedlOD2RNk=
+github.com/coreos/go-systemd v0.0.0-20190719114852-fd7a80b32e1f h1:JOrtw2xFKzlg+cbHpyrpLDmnN1HqhBfnX7WDiW7eG2c=
+github.com/coreos/go-systemd v0.0.0-20190719114852-fd7a80b32e1f/go.mod h1:F5haX7vjVVG0kc13fIWeqUViNPyEJxv/OmvnBo0Yme4=
 github.com/cpuguy83/go-md2man v1.0.10/go.mod h1:SmD6nW6nTyfqj6ABTjUi3V3JVMnlJmwcJI5acqYI6dE=
 github.com/cskr/pubsub v1.0.2 h1:vlOzMhl6PFn60gRlTQQsIfVwaPB/B/8MziK8FhEPt/0=
 github.com/cskr/pubsub v1.0.2/go.mod h1:/8MzYXk/NJAz782G8RPkFzXTZVu63VotefPnR9TIRis=

misc/systemd/ipfs-api.socket

+# Enabling this will *completely override* any API listeners configured in your
+# config.
+
+[Unit]
+Description=IPFS API Socket
+
+[Socket]
+Service=ipfs.service
+FileDescriptorName=io.ipfs.api
+BindIPv6Only=true
+ListenStream=127.0.0.1:5001
+ListenStream=[::1]:5001
+
+[Install]
+WantedBy=sockets.target

misc/systemd/ipfs-gateway.socket

+# Enabling this will *completely override* any Gateway listeners configured in
+# your config.
+
+[Unit]
+Description=IPFS Gateway Socket
+
+[Socket]
+Service=ipfs.service
+FileDescriptorName=io.ipfs.gateway
+BindIPv6Only=true
+ListenStream=127.0.0.1:8080
+ListenStream=[::1]:8080
+
+[Install]
+WantedBy=sockets.target

misc/systemd/ipfs.service

+[Unit]
+Description=IPFS Daemon
+
+[Service]
+ExecStart=/usr/bin/ipfs daemon --init --migrate
+KillSignal=SIGINT
+
+[Install]
+WantedBy=default.target