Create a script to update a ksonnet app to the latest Kubeflow package

* The script removes the existing registry named kubeflow and any packages
  installed from that registry
* It then readds Kubeflow using the supplied URL and reinstalls any packages.
* Related to: kubeflow/website#57
* Based on the script in ksonnet/ksonnet#237

scripts/upgrade_ks_app.py

@@ -0,0 +1,95 @@
+#!/usr/bin/env python
+import argparse
+import logging
+import os.path
+import shutil
+import subprocess
+import yaml
+
+# The path used by the bootstrapper
+BOOTSTRAPPER_REGISTRY = "/opt/registries/kubeflow/kubeflow"
+
+# The current release of Kubeflow. This should be upgraded on every release.
+CURRENT_RELEASE = "github.com/kubeflow/kubeflow/tree/v0.2.0-rc.1/kubeflow"
+
+# The default name for the registry.
+DEFAULT_REGISTRY_NAME = "kubeflow"
+
+def main():
+  logging.basicConfig(
+    level=logging.INFO,
+    format="%(levelname)s|%(asctime)s %(message)s",
+    datefmt="%Y-%m-%dT%H:%M:%S",
+  )
+  logging.getLogger().setLevel(logging.INFO)
+
+  parser = argparse.ArgumentParser()
+  parser.add_argument(
+      "--registry", default=CURRENT_RELEASE, type=str,
+      help=("The Kubeflow registry to use. This can be a GitHub link like "
+            "{0} that points at a specific version of the registry. "
+            "To specify the name of the registry in your ksonnet app "
+            "you can use the from <name>=<registry URL>").format(
+            CURRENT_RELEASE))
+
+  args = parser.parse_args()
+
+  if "=" in args.registry:
+    registry_name, registry_url = args.registry.split("=", 1)
+  else:
+    registry_name = DEFAULT_REGISTRY_NAME
+    registry_url = args.registry
+
+
+  with open('app.yaml', 'r') as f:
+    app = yaml.load(f)
+
+  registries = app['registries']
+  libraries = app['libraries']
+
+  for name in registries.iterkeys():
+    if name != registry_name:
+      logging.info("Skipping registry %s", name)
+      continue
+
+    if registries[name]["uri"].startswith("file"):
+      # File registries are not stored in .ksonnet
+      # TODO(jlewi): This messes with bootstrapper because we might want
+      # to switch from using the file URI to using the git location.
+      logging.info("Skipping registry %s because it is a file URI" % name)
+      continue
+    target = os.path.join('.ksonnet/registries', name)
+    if not os.path.exists(target):
+      logging.info("Warning directory %s doesn't exist; skipping" % target)
+      continue
+    shutil.rmtree(target)
+
+  for name in libraries.iterkeys():
+    target = os.path.join('vendor', libraries[name]["registry"], name)
+    if not os.path.exists(target):
+      logging.info("Directory does not exist: %s", target)
+      continue
+    shutil.rmtree(target)
+
+  del app['registries']
+  del app['libraries']
+
+  with open('app.yaml', 'w') as f:
+    yaml.dump(app, f, default_flow_style=False)
+
+  for name, registry in registries.iteritems():
+    if name != registry_name:
+      logging.info("Skipping registry %s", name)
+      continue
+    logging.info("Adding registry %s point at %s", name, registry_url)
+    subprocess.call(['ks', 'registry', 'add', name, registry_url])
+
+  for name, library in libraries.iteritems():
+    if library["registry"] != registry_name:
+      continue
+    package = "{0}/{1}".format(library["registry"], name)
+    logging.info("Installing package %s", package)
+    subprocess.call(['ks', 'pkg', 'install', package])
+
+if __name__ == "__main__":
+  main()