Add experimental documentation for stacks

Signed-off-by: Arnaud Porterie (icecrime) <arnaud.porterie@docker.com>

experimental/README.md

@@ -73,7 +73,7 @@ to build a Docker binary with the experimental features enabled:
 
  * [External graphdriver plugins](plugins_graphdriver.md)
  * [Macvlan and Ipvlan Network Drivers](vlan-networks.md)
- * The user namespaces feature has graduated from experimental.
+ * [Docker stacks](docker-stacks.md)
 
 ## How to comment on an experimental feature
 

experimental/docker-stacks.md

@@ -0,0 +1,98 @@
+# Docker Stacks
+
+## Overview
+
+Docker Stacks are an experimental feature introduced in Docker 1.12, alongside
+the new concepts of Swarms and Services inside the Engine.
+
+A Dockerfile can be built into an image, and containers can be created from that
+image. Similarly, a docker-compose.yml can be built into a **bundle**, and
+**stacks** can be created from that bundle. In that sense, the bundle is a
+multi-services distributable image format.
+
+As of 1.12, the feature is introduced as experimental, and Docker Engine doesn't
+support distribution of bundles.
+
+## Producing a bundle
+
+The easiest way to produce a bundle is to generate it using `docker-compose`
+from an existing `docker-compose.yml`. Of course, that's just *one* possible way
+to proceed, in the same way that `docker build` isn't the only way to produce a
+Docker image.
+
+From `docker-compose`:
+
+    ```bash
+    $ docker-compose bundle
+    WARNING: Unsupported key 'network_mode' in services.nsqd - ignoring
+    WARNING: Unsupported key 'links' in services.nsqd - ignoring
+    WARNING: Unsupported key 'volumes' in services.nsqd - ignoring
+    [...]
+    Wrote bundle to vossibility-stack.dsb
+    ```
+
+## Creating a stack from a bundle
+
+A stack is created using the `docker deploy` command:
+
+    ```bash
+    # docker deploy --help
+
+    Usage:  docker deploy [OPTIONS] STACK
+
+    Create and update a stack
+
+    Options:
+      -f, --bundle string   Path to a bundle (Default: STACK.dsb)
+          --help            Print usage
+    ```
+
+Let's deploy the stack created before:
+
+    ```bash
+    # docker deploy vossibility-stack
+    Loading bundle from vossibility-stack.dsb
+    Creating service vossibility-stack_elasticsearch
+    Creating service vossibility-stack_kibana
+    Creating service vossibility-stack_logstash
+    Creating service vossibility-stack_lookupd
+    Creating service vossibility-stack_nsqd
+    Creating service vossibility-stack_vossibility-collector
+    ```
+
+We can verify that services were correctly created:
+
+    ```bash
+    # docker service ls
+    ID            NAME                                     SCALE  IMAGE
+    COMMAND
+    29bv0vnlm903  vossibility-stack_lookupd                1 nsqio/nsq@sha256:eeba05599f31eba418e96e71e0984c3dc96963ceb66924dd37a47bf7ce18a662 /nsqlookupd
+    4awt47624qwh  vossibility-stack_nsqd                   1 nsqio/nsq@sha256:eeba05599f31eba418e96e71e0984c3dc96963ceb66924dd37a47bf7ce18a662 /nsqd --data-path=/data --lookupd-tcp-address=lookupd:4160
+    4tjx9biia6fs  vossibility-stack_elasticsearch          1 elasticsearch@sha256:12ac7c6af55d001f71800b83ba91a04f716e58d82e748fa6e5a7359eed2301aa
+    7563uuzr9eys  vossibility-stack_kibana                 1 kibana@sha256:6995a2d25709a62694a937b8a529ff36da92ebee74bafd7bf00e6caf6db2eb03
+    9gc5m4met4he  vossibility-stack_logstash               1 logstash@sha256:2dc8bddd1bb4a5a34e8ebaf73749f6413c101b2edef6617f2f7713926d2141fe logstash -f /etc/logstash/conf.d/logstash.conf
+    axqh55ipl40h  vossibility-stack_vossibility-collector  1 icecrime/vossibility-collector@sha256:f03f2977203ba6253988c18d04061c5ec7aab46bca9dfd89a9a1fa4500989fba --config /config/config.toml --debug
+    ```
+
+## Managing stacks
+
+Tasks are managed using the `docker stack` command:
+
+    ```bash
+    # docker stack --help
+
+    Usage:  docker stack COMMAND
+    
+    Manage Docker stacks
+    
+    Options:
+          --help   Print usage
+    
+    Commands:
+      config      Print the stack configuration
+      deploy      Create and update a stack
+      rm          Remove the stack
+      tasks       List the tasks in the stack
+    
+    Run 'docker stack COMMAND --help' for more information on a command.
+    ```