+"""
+This module implements a simple REST API that behaves like SONATA's gatekeeper.
+
+It is only used to support the development of SONATA's SDK tools and to demonstrate
+the year 1 version of the emulator until the integration with WP4's orchestrator is done.
+"""
+
+import logging
+import os
+import uuid
+import hashlib
+from flask import Flask, request
+import flask_restful as fr
+
+logging.getLogger("werkzeug").setLevel(logging.WARNING)
+
+
+UPLOAD_FOLDER = "/tmp/son-dummy-gk/uploads/"
+CATALOG_FOLDER = "/tmp/son-dummy-gk/catalog/"
+
+
+class Gatekeeper(object):
+
+ def __init__(self):
+ self.packages = dict()
+ self.instantiations = dict()
+ logging.info("Create SONATA dummy gatekeeper.")
+
+ def unpack_service_package(self, service_uuid):
+ # TODO implement method
+ # 1. unzip *.son file and store contents in CATALOG_FOLDER/services/<service_uuid>/
+ pass
+
+ def start_service(self, service_uuid):
+ # TODO implement method
+ # 1. parse descriptors
+ # 2. do the corresponding dc.startCompute(name="foobar") calls
+ # 3. store references to the compute objects in self.instantiations
+ pass
+
+
+"""
+Resource definitions and API endpoints
+"""
+
+
+class Packages(fr.Resource):
+
+ def post(self):
+ """
+ We expect request with a *.son file and store it in UPLOAD_FOLDER
+ """
+ try:
+ # get file contents
+ file = request.files['file']
+ # generate a uuid to reference this package
+ service_uuid = str(uuid.uuid4())
+ hash = hashlib.sha1(str(file)).hexdigest()
+ # ensure that upload folder exists
+ ensure_dir(UPLOAD_FOLDER)
+ upload_path = os.path.join(UPLOAD_FOLDER, "%s.son" % service_uuid)
+ # store *.son file to disk
+ file.save(upload_path)
+ size = os.path.getsize(upload_path)
+ # store a reference to the uploaded package in our gatekeeper
+ GK.packages[service_uuid] = upload_path
+ # generate the JSON result
+ return {"service_uuid": service_uuid, "size": size, "sha1": hash, "error": None}
+ except Exception as ex:
+ logging.exception("Service package upload failed:")
+ return {"service_uuid": None, "size": 0, "sha1": None, "error": "upload failed"}
+
+ def get(self):
+ return {"service_uuid_list": list(GK.packages.iterkeys())}
+
+
+class Instantiations(fr.Resource):
+
+ def post(self):
+ # TODO implement method
+ pass
+
+ def get(self):
+ # TODO implement method
+ pass
+
+# create a single, global GK object
+GK = Gatekeeper()
+# setup Flask
+app = Flask(__name__)
+app.config['MAX_CONTENT_LENGTH'] = 512 * 1024 * 1024 # 512 MB max upload
+api = fr.Api(app)
+# define endpoints
+api.add_resource(Packages, '/api/packages/uploads')
+api.add_resource(Instantiations, '/api/instantiations')
+
+
+def start_rest_api(host, port):
+ # start the Flask server (not the best performance but ok for our use case)
+ app.run(host=host,
+ port=port,
+ debug=True,
+ use_reloader=False # this is needed to run Flask in a non-main thread
+ )
+
+
+def ensure_dir(name):
+ if not os.path.exists(name):
+ os.makedirs(name)
+
+
+if __name__ == '__main__':
+ """
+ Lets allow to run the API in standalone mode.
+ """
+ logging.getLogger("werkzeug").setLevel(logging.INFO)
+ start_rest_api("0.0.0.0", 8000)
+