From 8943710092219509a7e0a59ca736a4593f1f9a8f Mon Sep 17 00:00:00 2001
From: Akihiro Suda <suda.akihiro@lab.ntt.co.jp>
Date: Fri, 29 Jul 2016 16:21:05 +0900
Subject: [PATCH] fs inspector support for namazu container

Fix #161
---
 README.md                    |  2 ++
 nmz/cli/container/run/run.go |  7 ++++++-
 nmz/container/fs.go          | 38 ++++++++++++++++++++++++++++++++++++
 nmz/container/start.go       | 32 +++++++++++++++++++++++++++++-
 nmz/util/config/config.go    |  1 +
 5 files changed, 78 insertions(+), 2 deletions(-)
 create mode 100644 nmz/container/fs.go

diff --git a/README.md b/README.md
index 1ab4167..c82ec24 100644
--- a/README.md
+++ b/README.md
@@ -117,6 +117,8 @@ explorePolicy = "random"
   # Default: true
   enableProcInspector = true
   procWatchInterval = "1s"
+  # Default: true (for volumes (`-v /foo:/bar`))
+  enableFSInspector = true
 ```
 For other parameters, please refer to [`config.go`](nmz/util/config/config.go) and [`randompolicy.go`](nmz/explorepolicy/random/randompolicy.go).
 
diff --git a/nmz/cli/container/run/run.go b/nmz/cli/container/run/run.go
index 761c8e1..5786088 100644
--- a/nmz/cli/container/run/run.go
+++ b/nmz/cli/container/run/run.go
@@ -89,6 +89,11 @@ func Run(args []string) int {
 		return 1
 	}
 
+	dockerOpt, err = container.StartNamazuRoutinesPre(dockerOpt, nmzCfg)
+	if err != nil {
+		panic(log.Critical(err))
+	}
+
 	client, err := ns.NewDockerClient()
 	if err != nil {
 		panic(log.Critical(err))
@@ -113,7 +118,7 @@ func Run(args []string) int {
 		log.Info("Namazu container is running the container in background, but Namazu itself keeps running in foreground.")
 	}
 
-	err = container.StartNamazuRoutines(c, nmzCfg)
+	err = container.StartNamazuRoutinesPost(c, nmzCfg)
 	if err != nil {
 		panic(log.Critical(err))
 	}
diff --git a/nmz/container/fs.go b/nmz/container/fs.go
new file mode 100644
index 0000000..8174687
--- /dev/null
+++ b/nmz/container/fs.go
@@ -0,0 +1,38 @@
+// Copyright (C) 2015 Nippon Telegraph and Telephone Corporation.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//    http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+// implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package container
+
+import (
+	"github.com/osrg/hookfs/hookfs"
+	"github.com/osrg/namazu/nmz/inspector/fs"
+	ocutil "github.com/osrg/namazu/nmz/util/orchestrator"
+)
+
+func ServeFSInspector(orig, mountpoint string) error {
+	hook := fs.FilesystemInspector{
+		OrchestratorURL: ocutil.LocalOrchestratorURL,
+		EntityID:        "_namazu_container_fs_inspector_" + orig,
+	}
+	fs, err := hookfs.NewHookFs(orig, mountpoint, &hook)
+	if err != nil {
+		return err
+	}
+	if err = fs.Serve(); err != nil {
+		return err
+	}
+	// NOTREACHED
+	return nil
+}
diff --git a/nmz/container/start.go b/nmz/container/start.go
index 37e2ae7..6f3b226 100644
--- a/nmz/container/start.go
+++ b/nmz/container/start.go
@@ -17,13 +17,15 @@ package container
 
 import (
 	"fmt"
+	"io/ioutil"
+	"strings"
 
 	log "github.com/cihub/seelog"
 	docker "github.com/fsouza/go-dockerclient"
 	"github.com/osrg/namazu/nmz/util/config"
 )
 
-func StartNamazuRoutines(c *docker.Container, cfg config.Config) error {
+func StartNamazuRoutinesPre(dockerOpt *docker.CreateContainerOptions, cfg config.Config) (*docker.CreateContainerOptions, error) {
 	log.Debugf("Starting Orchestrator")
 	go func() {
 		oerr := StartOrchestrator(cfg)
@@ -32,6 +34,34 @@ func StartNamazuRoutines(c *docker.Container, cfg config.Config) error {
 		}
 	}()
 
+	var newBinds []string
+	for _, bind := range dockerOpt.HostConfig.Binds {
+		split := strings.Split(bind, ":")
+		if len(split) != 2 {
+			return dockerOpt, fmt.Errorf("bind is expected to be <foo>:<bar>, got %s", bind)
+		}
+		bindSrc, bindDst := split[0], split[1]
+		mountpoint, err := ioutil.TempDir("", "nmz-container-fs-inspector")
+		if err != nil {
+			return dockerOpt, err
+		}
+		if cfg.GetBool("container.enableFSInspector") {
+			log.Debugf("Starting Filesystem Inspector for %s (on %s)", bindSrc, mountpoint)
+			log.Warnf("Please run `fusermount -i %s` manually on exit", mountpoint)
+			go func() {
+				ierr := ServeFSInspector(bindSrc, mountpoint)
+				if ierr != nil {
+					panic(log.Critical(ierr))
+				}
+			}()
+		}
+		newBinds = append(newBinds, fmt.Sprintf("%s:%s", mountpoint, bindDst))
+	}
+	dockerOpt.HostConfig.Binds = newBinds
+	return dockerOpt, nil
+}
+
+func StartNamazuRoutinesPost(c *docker.Container, cfg config.Config) error {
 	if cfg.GetBool("container.enableEthernetInspector") {
 		nfqNum := cfg.GetInt("container.ethernetNFQNumber")
 		if nfqNum <= 0 {
diff --git a/nmz/util/config/config.go b/nmz/util/config/config.go
index 1697f9e..aa94a29 100644
--- a/nmz/util/config/config.go
+++ b/nmz/util/config/config.go
@@ -90,6 +90,7 @@ func New() Config {
 	cfg.SetDefault("container", map[string]interface{}{
 		"enableEthernetInspector": false,
 		"enableProcInspector":     true,
+		"enableFSInspector":       true,
 		"ethernetNFQNumber":       42,
 		"procWatchInterval":       time.Second,
 	})