From 045dd55a7d652b693ff34cbfcc3a2c97d46fbc4b Mon Sep 17 00:00:00 2001
From: Arnaud Porterie <arnaud.porterie@docker.com>
Date: Tue, 19 May 2015 15:09:58 -0700
Subject: [PATCH] Add DOCKER_EXPERIMENTAL environment variable

The DOCKER_EXPERIMENTAL environment variable drives the activation of
the 'experimental' build tag.

Signed-off-by: Arnaud Porterie <arnaud.porterie@docker.com>
Upstream-commit: ca6722f1c5e4e2017a71e33579d91ac0d9ea2a25
Component: engine
---
 components/engine/Makefile                                 | 1 +
 components/engine/api/client/info.go                       | 1 +
 components/engine/api/types/types.go                       | 1 +
 components/engine/daemon/info.go                           | 1 +
 components/engine/docker/docker.go                         | 5 +++++
 .../docs/sources/reference/api/docker_remote_api_v1.19.md  | 1 +
 components/engine/hack/make.sh                             | 6 ++++++
 components/engine/utils/experimental.go                    | 7 +++++++
 components/engine/utils/stubs.go                           | 7 +++++++
 9 files changed, 30 insertions(+)
 create mode 100644 components/engine/utils/experimental.go
 create mode 100644 components/engine/utils/stubs.go

diff --git a/components/engine/Makefile b/components/engine/Makefile
index b98424b6c0..054720f921 100644
--- a/components/engine/Makefile
+++ b/components/engine/Makefile
@@ -7,6 +7,7 @@ DOCKER_ENVS := \
 	-e BUILDFLAGS \
 	-e DOCKER_CLIENTONLY \
 	-e DOCKER_EXECDRIVER \
+	-e DOCKER_EXPERIMENTAL \
 	-e DOCKER_GRAPHDRIVER \
 	-e DOCKER_STORAGE_OPTS \
 	-e TESTDIRS \
diff --git a/components/engine/api/client/info.go b/components/engine/api/client/info.go
index 06a6f0ec54..918b6bbe7a 100644
--- a/components/engine/api/client/info.go
+++ b/components/engine/api/client/info.go
@@ -87,6 +87,7 @@ func (cli *DockerCli) CmdInfo(args ...string) error {
 			fmt.Fprintf(cli.out, " %s\n", attribute)
 		}
 	}
+	fmt.Fprintf(cli.out, "Experimental: %t\n", info.ExperimentalBuild)
 
 	return nil
 }
diff --git a/components/engine/api/types/types.go b/components/engine/api/types/types.go
index 56219f845e..457808f5e9 100644
--- a/components/engine/api/types/types.go
+++ b/components/engine/api/types/types.go
@@ -168,6 +168,7 @@ type Info struct {
 	NoProxy            string
 	Name               string
 	Labels             []string
+	ExperimentalBuild  bool
 }
 
 // This struct is a temp struct used by execStart
diff --git a/components/engine/daemon/info.go b/components/engine/daemon/info.go
index 2cd1e5bc65..edec5f9ff7 100644
--- a/components/engine/daemon/info.go
+++ b/components/engine/daemon/info.go
@@ -85,6 +85,7 @@ func (daemon *Daemon) SystemInfo() (*types.Info, error) {
 		MemTotal:           meminfo.MemTotal,
 		DockerRootDir:      daemon.Config().Root,
 		Labels:             daemon.Config().Labels,
+		ExperimentalBuild:  utils.ExperimentalBuild(),
 	}
 
 	if httpProxy := os.Getenv("http_proxy"); httpProxy != "" {
diff --git a/components/engine/docker/docker.go b/components/engine/docker/docker.go
index fd40f4b422..84457b177d 100644
--- a/components/engine/docker/docker.go
+++ b/components/engine/docker/docker.go
@@ -16,6 +16,7 @@ import (
 	flag "github.com/docker/docker/pkg/mflag"
 	"github.com/docker/docker/pkg/reexec"
 	"github.com/docker/docker/pkg/term"
+	"github.com/docker/docker/utils"
 )
 
 const (
@@ -59,6 +60,10 @@ func main() {
 		setLogLevel(logrus.DebugLevel)
 	}
 
+	if utils.ExperimentalBuild() {
+		logrus.Warn("Running experimental build")
+	}
+
 	if len(flHosts) == 0 {
 		defaultHost := os.Getenv("DOCKER_HOST")
 		if defaultHost == "" || *flDaemon {
diff --git a/components/engine/docs/sources/reference/api/docker_remote_api_v1.19.md b/components/engine/docs/sources/reference/api/docker_remote_api_v1.19.md
index c9b780ea2b..5fec8b811c 100644
--- a/components/engine/docs/sources/reference/api/docker_remote_api_v1.19.md
+++ b/components/engine/docs/sources/reference/api/docker_remote_api_v1.19.md
@@ -1620,6 +1620,7 @@ Display system-wide information
             "Driver": "btrfs",
             "DriverStatus": [[""]],
             "ExecutionDriver": "native-0.1",
+            "ExperimentalBuild": false,
             "HttpProxy": "http://test:test@localhost:8080",
             "HttpsProxy": "https://test:test@localhost:8080",
             "ID": "7TRN:IPZB:QYBB:VPBQ:UMPP:KARE:6ZNR:XE6T:7EWV:PKF4:ZOJD:TPYS",
diff --git a/components/engine/hack/make.sh b/components/engine/hack/make.sh
index b9c2aef6a8..e43f360e82 100755
--- a/components/engine/hack/make.sh
+++ b/components/engine/hack/make.sh
@@ -93,6 +93,12 @@ if [ ! "$GOPATH" ]; then
 	exit 1
 fi
 
+if [ "$DOCKER_EXPERIMENTAL" ]; then
+	echo >&2 '# WARNING! DOCKER_EXPERIMENTAL is set: building experimental features'
+	echo >&2
+	DOCKER_BUILDTAGS+=" experimental"
+fi
+
 if [ -z "$DOCKER_CLIENTONLY" ]; then
 	DOCKER_BUILDTAGS+=" daemon"
 fi
diff --git a/components/engine/utils/experimental.go b/components/engine/utils/experimental.go
new file mode 100644
index 0000000000..b308a59faf
--- /dev/null
+++ b/components/engine/utils/experimental.go
@@ -0,0 +1,7 @@
+// +build experimental
+
+package utils
+
+func ExperimentalBuild() bool {
+	return true
+}
diff --git a/components/engine/utils/stubs.go b/components/engine/utils/stubs.go
new file mode 100644
index 0000000000..b376f0cfb5
--- /dev/null
+++ b/components/engine/utils/stubs.go
@@ -0,0 +1,7 @@
+// +build !experimental
+
+package utils
+
+func ExperimentalBuild() bool {
+	return false
+}