From 4958b8d37a6bf631537c06046188dca9bc87c5ab Mon Sep 17 00:00:00 2001
From: Paul Bellamy <paul.a.bellamy@gmail.com>
Date: Wed, 29 Jul 2015 15:51:51 +0100
Subject: [PATCH] [proxy] Mount /w from the host for weavewaited containers

We set it at container create. Had tried also setting it at start, but
it seems to cause weird behaviour, and there is no way to do it from the
CLI.
---
 proxy/create_container_interceptor.go | 14 +++++++++++-
 proxy/proxy.go                        | 31 ++++++++++++++++++++++++---
 test/610_proxy_wait_for_weave_test.sh |  5 +++++
 3 files changed, 46 insertions(+), 4 deletions(-)

diff --git a/proxy/create_container_interceptor.go b/proxy/create_container_interceptor.go
index ee5c43ed..5b6bfd7b 100644
--- a/proxy/create_container_interceptor.go
+++ b/proxy/create_container_interceptor.go
@@ -53,10 +53,10 @@ func (i *createContainerInterceptor) InterceptRequest(r *http.Request) error {
 		if container.HostConfig == nil {
 			container.HostConfig = &docker.HostConfig{}
 		}
-		container.HostConfig.VolumesFrom = append(container.HostConfig.VolumesFrom, "weaveproxy:ro")
 		if container.Config == nil {
 			container.Config = &docker.Config{}
 		}
+		i.addWeaveWaitVolume(container.HostConfig)
 		if err := i.setWeaveWaitEntrypoint(container.Config); err != nil {
 			return err
 		}
@@ -75,6 +75,18 @@ func (i *createContainerInterceptor) InterceptRequest(r *http.Request) error {
 	return nil
 }
 
+func (i *createContainerInterceptor) addWeaveWaitVolume(hostConfig *docker.HostConfig) {
+	var binds []string
+	for _, bind := range hostConfig.Binds {
+		s := strings.Split(bind, ":")
+		if len(s) >= 2 && s[1] == "/w" {
+			continue
+		}
+		binds = append(binds, bind)
+	}
+	hostConfig.Binds = append(binds, fmt.Sprintf("%s:/w:ro", i.proxy.weaveWaitVolume))
+}
+
 func (i *createContainerInterceptor) setWeaveWaitEntrypoint(container *docker.Config) error {
 	if len(container.Entrypoint) == 0 {
 		image, err := i.proxy.client.InspectImage(container.Image)
diff --git a/proxy/proxy.go b/proxy/proxy.go
index d454a06c..b42a582d 100644
--- a/proxy/proxy.go
+++ b/proxy/proxy.go
@@ -3,6 +3,7 @@ package proxy
 import (
 	"crypto/tls"
 	"errors"
+	"fmt"
 	"net"
 	"net/http"
 	"net/url"
@@ -32,9 +33,10 @@ var (
 type Proxy struct {
 	Config
 
-	dial           func() (net.Conn, error)
-	client         *docker.Client
-	dockerBridgeIP string
+	dial            func() (net.Conn, error)
+	client          *docker.Client
+	dockerBridgeIP  string
+	weaveWaitVolume string
 }
 
 type Config struct {
@@ -85,9 +87,32 @@ func NewProxy(c Config) (*Proxy, error) {
 		return nil, err
 	}
 
+	if err = p.findWeaveWaitVolume(); err != nil {
+		return nil, err
+	}
+
 	return p, nil
 }
 
+func (proxy *Proxy) findWeaveWaitVolume() error {
+	container, err := proxy.client.InspectContainer("weaveproxy")
+	if err != nil {
+		return fmt.Errorf("Could not find the weavewait volume: %s", err)
+	}
+
+	if container.Volumes == nil {
+		return fmt.Errorf("Could not find the weavewait volume")
+	}
+
+	volume, ok := container.Volumes["/w"]
+	if !ok {
+		return fmt.Errorf("Could not find the weavewait volume")
+	}
+
+	proxy.weaveWaitVolume = volume
+	return nil
+}
+
 func (proxy *Proxy) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 	Info.Printf("%s %s", r.Method, r.URL)
 	path := r.URL.Path
diff --git a/test/610_proxy_wait_for_weave_test.sh b/test/610_proxy_wait_for_weave_test.sh
index ddc63b3d..1d5e1276 100755
--- a/test/610_proxy_wait_for_weave_test.sh
+++ b/test/610_proxy_wait_for_weave_test.sh
@@ -28,4 +28,9 @@ assert_raises "proxy docker_on $HOST1 exec c3 true"
 # Check we can't modify weavewait
 assert_raises "proxy docker_on $HOST1 run -e 'WEAVE_CIDR=10.2.1.2/24' $BASE_IMAGE touch /w/w" 1
 
+# Check only user-specified volumes and /w are mounted
+proxy docker_on $HOST1 create --name c4 -v /tmp/1:/srv1 -v /tmp/2:/srv2 -e 'WEAVE_CIDR=10.2.1.3/24' $BASE_IMAGE $CHECK_ETHWE_UP
+proxy docker_on $HOST1 start -ai c4
+assert "docker_on $HOST1 inspect --format='{{range \$k, \$v := .Volumes}}{{\$k}} {{end}}' c4" "/srv1 /srv2 /w "
+
 end_suite