This patch adds a RESTful HTTP interface to Asterisk.

The API itself is documented using Swagger, a lightweight mechanism for
documenting RESTful API's using JSON. This allows us to use swagger-ui
to provide executable documentation for the API, generate client
bindings in different languages, and generate a lot of the boilerplate
code for implementing the RESTful bindings. The API docs live in the
rest-api/ directory.

The RESTful bindings are generated from the Swagger API docs using a set
of Mustache templates.  The code generator is written in Python, and
uses Pystache. Pystache has no dependencies, and be installed easily
using pip. Code generation code lives in rest-api-templates/.

The generated code reduces a lot of boilerplate when it comes to
handling HTTP requests. It also helps us have greater consistency in the
REST API.

(closes issue ASTERISK-20891)
Review: https://reviewboard.asterisk.org/r/2376/

git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@386232 65c4cc65-6c06-0410-ace0-fbb531ad65f3

rest-api-templates/transform.py

@@ -0,0 +1,53 @@
+#
+# Asterisk -- An open source telephony toolkit.
+#
+# Copyright (C) 2013, Digium, Inc.
+#
+# David M. Lee, II <dlee@digium.com>
+#
+# See http://www.asterisk.org for more information about
+# the Asterisk project. Please do not directly contact
+# any of the maintainers of this project for assistance;
+# the project provides a web site, mailing lists and IRC
+# channels for your use.
+#
+# This program is free software, distributed under the terms of
+# the GNU General Public License Version 2. See the LICENSE file
+# at the top of the source tree.
+#
+
+import os.path
+import pystache
+
+
+class Transform(object):
+    """Transformation for template to code.
+    """
+    def __init__(self, template_file, dest_file_template_str, overwrite=True):
+        """Ctor.
+
+        @param template_file: Filename of the mustache template.
+        @param dest_file_template_str: Destination file name. This is a
+            mustache template, so each resource can write to a unique file.
+        @param overwrite: If True, destination file is ovewritten if it exists.
+        """
+        template_str = unicode(open(template_file, "r").read())
+        self.template = pystache.parse(template_str)
+        dest_file_template_str = unicode(dest_file_template_str)
+        self.dest_file_template = pystache.parse(dest_file_template_str)
+        self.overwrite = overwrite
+
+    def render(self, renderer, model, dest_dir):
+        """Render a model according to this transformation.
+
+        @param render: Pystache renderer.
+        @param model: Model object to render.
+        @param dest_dir: Destination directory to write generated code.
+        """
+        dest_file = pystache.render(self.dest_file_template, model)
+        dest_file = os.path.join(dest_dir, dest_file)
+        if os.path.exists(dest_file) and not self.overwrite:
+            return
+        print "Rendering %s" % dest_file
+        with open(dest_file, "w") as out:
+            out.write(renderer.render(self.template, model))