Add README and LICENSE

LICENSE

@@ -0,0 +1,21 @@
+The MIT License (MIT)
+
+Copyright (c) 2015 Cash Payment Solutions GmbH
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

README.md

@@ -0,0 +1,44 @@
+# waitforservices
+
+A small utility waiting for services linked to a Docker container being ready.
+
+Without configuration, it finds all TCP services linked to a Docker container via their [environment variables](http://docs.docker.com/userguide/dockerlinks/#environment-variables) and concurrently and repeatedly tries to open a TCP connection to all of them.
+
+When all connections are successful, it returns. If one or more services aren't ready within 60 seconds, it aborts and exits with status 1.
+
+`waitforservices` also supports waiting for an HTTP request to `/` to return a response.
+
+## Installation
+
+First, install the utility into your image by adding this to your Dockerfile:
+
+    RUN curl -LsS https://github.com/Barzahlen/waitforservices/releases/download/0.1/waitforservices \
+            > /usr/local/bin/waitforservices && \
+        chmod +x /usr/local/bin/waitforservices
+
+There's also a Makefile in this repository if you want to build the binary yourself.
+
+Then, during container startup, you can use the `waitforservices` command to wait for all services being ready.
+
+## Usage
+
+    $ ./waitforservice -help
+    Usage of ./waitforservices:
+      -httpport=0: wait for an http request if target port is given port
+      -ignoreport=0: don't wait for services on this port to be up
+      -timeout=60: time to wait for all services to be up (seconds)
+
+    Attempt to connect to all TCP services linked to a Docker container (found
+    via their env vars) and wait for them to accept a TCP connection.
+
+    When an <httpport> is specified, for services running on <httpport>, after
+    a successful TCP connect, do an HTTP request and wait until it's done. This
+    is useful for slow-starting services that only start up when they receive
+    their first request.
+
+    When timeout is over and TCP connect or HTTP request were unsucecssful, exit
+    with status 1.
+
+## License
+
+waitforservices is licensed under [MIT](LICENSE).