WIP: Start implementation of the build manager/controller. This code is not yet working completely.

buildman/buildpack.py

@@ -0,0 +1,86 @@
+import tarfile
+
+from tempfile import TemporaryFile, mkdtemp
+from zipfile import ZipFile
+from util.dockerfileparse import parse_dockerfile, ParsedDockerfile
+
+
+class BuildPackageException(Exception):
+  """ Exception raised when retrieving or parsing a build package. """
+  pass
+
+
+class BuildPackage(object):
+  """ Helper class for easy reading and updating of a Dockerfile build pack. """
+
+  def __init__(self, requests_file):  
+    self._mime_processors = {
+      'application/zip': BuildPack.__prepare_zip,
+      'application/x-zip-compressed': BuildPack.__prepare_zip,
+      'text/plain': BuildPack.__prepare_dockerfile,
+      'application/octet-stream': BuildPack.__prepare_dockerfile,
+      'application/x-tar': BuildPack.__prepare_tarball,
+      'application/gzip': BuildPack.__prepare_tarball,
+      'application/x-gzip': BuildPack.__prepare_tarball,
+    }
+
+    c_type = buildpack_resource.headers['content-type']
+    c_type = c_type.split(';')[0] if ';' in c_type else c_type
+
+    if c_type not in self._mime_processors:
+      raise BuildPackageException('Unknown build package mime type: %s' % c_type)
+
+    self._package_directory = None
+    try:
+      self._package_directory = self._mime_processors[c_type](requests_file)
+    except Exception as ex:
+      raise BuildPackageException(ex.message)
+
+  def parse_dockerfile(self, build_subdirectory):
+    dockerfile_path = os.path.join(self._package_directory, subdirectory, 'Dockerfile')
+    if not os.path.exists(dockerfile_path):
+      if subdirectory:
+        message = 'Build package did not contain a Dockerfile at sub directory %s.' % subdirectory
+      else:
+        message = 'Build package did not contain a Dockerfile at the root directory.'
+
+      raise BuildPackageException(message)
+
+    with open(dockerfile_path, 'r') as dockerfileobj:
+      return parse_dockerfile(dockerfileobj.read())
+
+  @classmethod
+  def from_url(url):
+    buildpack_resource = requests.get(buildpack_url, stream=True)
+    return BuildPackage(buildpack_resource, c_type)
+
+  @staticmethod
+  def __prepare_zip(request_file):
+    build_dir = mkdtemp(prefix='docker-build-')
+
+    # Save the zip file to temp somewhere
+    with TemporaryFile() as zip_file:
+      zip_file.write(request_file.content)
+      to_extract = ZipFile(zip_file)
+      to_extract.extractall(build_dir)
+
+    return build_dir
+
+  @staticmethod
+  def __prepare_dockerfile(request_file):
+    build_dir = mkdtemp(prefix='docker-build-')
+    dockerfile_path = os.path.join(build_dir, "Dockerfile")
+    with open(dockerfile_path, 'w') as dockerfile:
+      dockerfile.write(request_file.content)
+
+    return build_dir
+
+  @staticmethod
+  def __prepare_tarball(request_file):
+    build_dir = mkdtemp(prefix='docker-build-')
+
+    # Save the zip file to temp somewhere
+    with tarfile.open(mode='r|*', fileobj=request_file.raw) as tar_stream:
+      safe_extractall(tar_stream, build_dir)
+
+    return build_dir