update README and Dockerfile

Author: andrewsg

README

@@ -0,0 +1,79 @@
+Google Managed VMs Python Runtime
+
+Warning
+=======
+
+The instructions here are for a multi-process version of the Python 2.7 runtime
+**currently in alpha**. Please do not use this version for production workloads.
+To use the stable version of the runtime, follow the documentation at
+https://cloud.google.com/appengine/docs/managed-vms/ instead.
+
+Contents
+========
+
+   * Using the multi-process runtime
+   * Configuration
+   * Building your own version
+
+Using the multi-process runtime
+===============================
+*These instructions assume you have a working Python application that has
+already been deployed successfully to Managed VMs using the default runtime
+version.*
+
+As this version of the Python runtime is currently in alpha, it is not built
+as a stable Docker image like other runtimes. Instead it can be put into place
+via modifications to an application's Dockerfile.
+
+If your application has an automatically generated Dockerfile (this will be
+created during the deployment process the first time your app is deployed),
+copy multicore_runtime/dev/Dockerfile from this repository to your application
+directory.
+
+If your application has a custom Dockerfile, then compare the two files and
+merge them. In typical cases this can be done by removing the first line of your
+application's Dockerfile (starting with FROM) and the last line of
+multicore_runtime/dev/Dockerfile (ADD . /app) and concatenating the files, with
+the repository's version first.
+
+This Dockerfile will download the latest release of the runtime directly from
+Github. If you would like to instead use a version of the runtime you have
+modified or that has not yet been released, see the "Building your own version"
+section.
+
+*Post-release, this version of the Python runtime will be made available as a
+prebuilt Docker image with no manual Dockerfile modification required.*
+
+Configuration
+=============
+By default the multi-process version of the runtime is launched via the Gunicorn
+webserver and is configured to use a fixed number of processes and gevent-based
+concurrency.
+
+This can be changed by editing the ENTRYPOINT line in the Dockerfile. For
+instance, Gunicorn can be changed to Waitress or another Python webserver, or
+the number of processes can be increased, or gevent-based concurrency can be
+turned off.
+
+A future version of this runtime may automatically adapt the default settings to
+accommodate a given instance size. This version instead uses a fixed number of
+processes. If you are using an instance type with more than 4 CPU cores, change
+the number of processes in the Dockerfile to between 1 and 2 times the number of
+CPU cores available.
+
+Building your own version
+=========================
+If you would like to make modifications to the runtime (either for personal use
+or to debug or resolve an outstanding issue), you can build and deploy a custom
+version with the following steps:
+
+- After cloning the repository locally and making your changes, build a source
+distribution by running `python setup.py sdist` from the root directory of the
+repository.
+- Copy the resulting tar.gz file to your application's folder, in the same
+directory as the Dockerfile.
+- Edit the Dockerfile in your application and look for the line that says
+`COPY (...) /home/vmagent/python-runtime.tar.gz`
+- Replace the URL in that line with the filename of your generated tar.gz file.
+- Deploy your application. A warning during deployment where your tar.gz file is
+rejected for addition because it is too large can be ignored.

README.md

@@ -5,7 +5,7 @@ RUN apt-get -q update && \
     python2.7 python-pip python-gevent python-greenlet && \
   apt-get clean && rm /var/lib/apt/lists/*_*
 
-COPY appengine-python-vm-runtime-0.1.tar.gz /home/vmagent/python-runtime.tar.gz
+COPY https://github.com/GoogleCloudPlatform/appengine-python-vm-runtime/releases/download/0.1/python-runtime-0.1.tar.gz /home/vmagent/python-runtime.tar.gz
 
 RUN pip install --upgrade pip>=6.1.1 gunicorn==19.1.1
 RUN pip install /home/vmagent/python-runtime.tar.gz