src/emuvim/api/sonata/dummygatekeeper.py

   1 """
   2 This module implements a simple REST API that behaves like SONATA's gatekeeper.
   3
   4 It is only used to support the development of SONATA's SDK tools and to demonstrate
   5 the year 1 version of the emulator until the integration with WP4's orchestrator is done.
   6 """
   7
   8 import logging
   9 import os
  10 import uuid
  11 import hashlib
  12 import zipfile
  13 import yaml
  14 from docker import Client as DockerClient
  15 from flask import Flask, request
  16 import flask_restful as fr
  17
  18 logging.basicConfig()
  19 LOG = logging.getLogger("sonata-dummy-gatekeeper")
  20 LOG.setLevel(logging.DEBUG)
  21 logging.getLogger("werkzeug").setLevel(logging.WARNING)
  22
  23 GK_STORAGE = "/tmp/son-dummy-gk/"
  24 UPLOAD_FOLDER = os.path.join(GK_STORAGE, "uploads/")
  25 CATALOG_FOLDER = os.path.join(GK_STORAGE, "catalog/")
  26
  27 # Enable Dockerfile build functionality
  28 BUILD_DOCKERFILE = False
  29
  30 # flag to indicate that we run without the emulator (only the bare API for integration testing)
  31 GK_STANDALONE_MODE = False
  32
  33 # should a new version of an image be pulled even if its available
  34 FORCE_PULL = True
  35
  36
  37 class Gatekeeper(object):
  38
  39     def __init__(self):
  40         self.services = dict()
  41         self.dcs = dict()
  42         self.vnf_counter = 0  # used to generate short names for VNFs (Mininet limitation)
  43         LOG.info("Create SONATA dummy gatekeeper.")
  44
  45     def register_service_package(self, service_uuid, service):
  46         """
  47         register new service package
  48         :param service_uuid
  49         :param service object
  50         """
  51         self.services[service_uuid] = service
  52         # lets perform all steps needed to onboard the service
  53         service.onboard()
  54
  55     def get_next_vnf_name(self):
  56         self.vnf_counter += 1
  57         return "vnf%d" % self.vnf_counter
  58
  59
  60 class Service(object):
  61     """
  62     This class represents a NS uploaded as a *.son package to the
  63     dummy gatekeeper.
  64     Can have multiple running instances of this service.
  65     """
  66
  67     def __init__(self,
  68                  service_uuid,
  69                  package_file_hash,
  70                  package_file_path):
  71         self.uuid = service_uuid
  72         self.package_file_hash = package_file_hash
  73         self.package_file_path = package_file_path
  74         self.package_content_path = os.path.join(CATALOG_FOLDER, "services/%s" % self.uuid)
  75         self.manifest = None
  76         self.nsd = None
  77         self.vnfds = dict()
  78         self.local_docker_files = dict()
  79         self.remote_docker_image_urls = dict()
  80         self.instances = dict()
  81
  82     def onboard(self):
  83         """
  84         Do all steps to prepare this service to be instantiated
  85         :return:
  86         """
  87         # 1. extract the contents of the package and store them in our catalog
  88         self._unpack_service_package()
  89         # 2. read in all descriptor files
  90         self._load_package_descriptor()
  91         self._load_nsd()
  92         self._load_vnfd()
  93         # 3. prepare container images (e.g. download or build Dockerfile)
  94         if BUILD_DOCKERFILE:
  95             self._load_docker_files()
  96             self._build_images_from_dockerfiles()
  97         else:
  98             self._load_docker_urls()
  99             self._pull_predefined_dockerimages()
 100         LOG.info("On-boarded service: %r" % self.manifest.get("package_name"))
 101
 102     def start_service(self):
 103         """
 104         This methods creates and starts a new service instance.
 105         It computes placements, iterates over all VNFDs, and starts
 106         each VNFD as a Docker container in the data center selected
 107         by the placement algorithm.
 108         :return:
 109         """
 110         LOG.info("Starting service %r" % self.uuid)
 111         # 1. each service instance gets a new uuid to identify it
 112         instance_uuid = str(uuid.uuid4())
 113         # build a instances dict (a bit like a NSR :))
 114         self.instances[instance_uuid] = dict()
 115         self.instances[instance_uuid]["vnf_instances"] = list()
 116         # 2. compute placement of this service instance (adds DC names to VNFDs)
 117         if not GK_STANDALONE_MODE:
 118             self._calculate_placement(FirstDcPlacement)
 119         # iterate over all vnfds that we have to start
 120         for vnfd in self.vnfds.itervalues():
 121             vnfi = None
 122             if not GK_STANDALONE_MODE:
 123                 vnfi = self._start_vnfd(vnfd)
 124             self.instances[instance_uuid]["vnf_instances"].append(vnfi)
 125         LOG.info("Service started. Instance id: %r" % instance_uuid)
 126         return instance_uuid
 127
 128     def _start_vnfd(self, vnfd):
 129         """
 130         Start a single VNFD of this service
 131         :param vnfd: vnfd descriptor dict
 132         :return:
 133         """
 134         # iterate over all deployment units within each VNFDs
 135         for u in vnfd.get("virtual_deployment_units"):
 136             # 1. get the name of the docker image to start and the assigned DC
 137             vnf_name = vnfd.get("name")
 138             if vnf_name not in self.remote_docker_image_urls:
 139                 raise Exception("No image name for %r found. Abort." % vnf_name)
 140             docker_name = self.remote_docker_image_urls.get(vnf_name)
 141             target_dc = vnfd.get("dc")
 142             # 2. perform some checks to ensure we can start the container
 143             assert(docker_name is not None)
 144             assert(target_dc is not None)
 145             if not self._check_docker_image_exists(docker_name):
 146                 raise Exception("Docker image %r not found. Abort." % docker_name)
 147             # 3. do the dc.startCompute(name="foobar") call to run the container
 148             # TODO consider flavors, and other annotations
 149             vnfi = target_dc.startCompute(GK.get_next_vnf_name(), image=docker_name, flavor_name="small")
 150             # 6. store references to the compute objects in self.instances
 151             return vnfi
 152
 153     def _unpack_service_package(self):
 154         """
 155         unzip *.son file and store contents in CATALOG_FOLDER/services/<service_uuid>/
 156         """
 157         LOG.info("Unzipping: %r" % self.package_file_path)
 158         with zipfile.ZipFile(self.package_file_path, "r") as z:
 159             z.extractall(self.package_content_path)
 160
 161
 162     def _load_package_descriptor(self):
 163         """
 164         Load the main package descriptor YAML and keep it as dict.
 165         :return:
 166         """
 167         self.manifest = load_yaml(
 168             os.path.join(
 169                 self.package_content_path, "META-INF/MANIFEST.MF"))
 170
 171     def _load_nsd(self):
 172         """
 173         Load the entry NSD YAML and keep it as dict.
 174         :return:
 175         """
 176         if "entry_service_template" in self.manifest:
 177             nsd_path = os.path.join(
 178                 self.package_content_path,
 179                 make_relative_path(self.manifest.get("entry_service_template")))
 180             self.nsd = load_yaml(nsd_path)
 181             LOG.debug("Loaded NSD: %r" % self.nsd.get("name"))
 182
 183     def _load_vnfd(self):
 184         """
 185         Load all VNFD YAML files referenced in MANIFEST.MF and keep them in dict.
 186         :return:
 187         """
 188         if "package_content" in self.manifest:
 189             for pc in self.manifest.get("package_content"):
 190                 if pc.get("content-type") == "application/sonata.function_descriptor":
 191                     vnfd_path = os.path.join(
 192                         self.package_content_path,
 193                         make_relative_path(pc.get("name")))
 194                     vnfd = load_yaml(vnfd_path)
 195                     self.vnfds[vnfd.get("name")] = vnfd
 196                     LOG.debug("Loaded VNFD: %r" % vnfd.get("name"))
 197
 198     def _load_docker_files(self):
 199         """
 200         Get all paths to Dockerfiles from VNFDs and store them in dict.
 201         :return:
 202         """
 203         for k, v in self.vnfds.iteritems():
 204             for vu in v.get("virtual_deployment_units"):
 205                 if vu.get("vm_image_format") == "docker":
 206                     vm_image = vu.get("vm_image")
 207                     docker_path = os.path.join(
 208                         self.package_content_path,
 209                         make_relative_path(vm_image))
 210                     self.local_docker_files[k] = docker_path
 211                     LOG.debug("Found Dockerfile (%r): %r" % (k, docker_path))
 212
 213     def _load_docker_urls(self):
 214         """
 215         Get all URLs to pre-build docker images in some repo.
 216         :return:
 217         """
 218         for k, v in self.vnfds.iteritems():
 219             for vu in v.get("virtual_deployment_units"):
 220                 if vu.get("vm_image_format") == "docker":
 221                     url = vu.get("vm_image")
 222                     if url is not None:
 223                         url = url.replace("http://", "")
 224                         self.remote_docker_image_urls[k] = url
 225                         LOG.debug("Found Docker image URL (%r): %r" % (k, self.remote_docker_image_urls[k]))
 226
 227     def _build_images_from_dockerfiles(self):
 228         """
 229         Build Docker images for each local Dockerfile found in the package: self.local_docker_files
 230         """
 231         if GK_STANDALONE_MODE:
 232             return  # do not build anything in standalone mode
 233         dc = DockerClient()
 234         LOG.info("Building %d Docker images (this may take several minutes) ..." % len(self.local_docker_files))
 235         for k, v in self.local_docker_files.iteritems():
 236             for line in dc.build(path=v.replace("Dockerfile", ""), tag=k, rm=False, nocache=False):
 237                 LOG.debug("DOCKER BUILD: %s" % line)
 238             LOG.info("Docker image created: %s" % k)
 239
 240     def _pull_predefined_dockerimages(self):
 241         """
 242         If the package contains URLs to pre-build Docker images, we download them with this method.
 243         """
 244         dc = DockerClient()
 245         for url in self.remote_docker_image_urls.itervalues():
 246             if not FORCE_PULL:  # only pull if not present (speedup for development)
 247                 if len(dc.images(name=url)) > 0:
 248                     LOG.debug("Image %r present. Skipping pull." % url)
 249                     continue
 250             LOG.info("Pulling image: %r" % url)
 251             dc.pull(url,
 252                     insecure_registry=True)
 253
 254     def _check_docker_image_exists(self, image_name):
 255         """
 256         Query the docker service and check if the given image exists
 257         :param image_name: name of the docker image
 258         :return:
 259         """
 260         return len(DockerClient().images(image_name)) > 0
 261
 262     def _calculate_placement(self, algorithm):
 263         """
 264         Do placement by adding the a field "dc" to
 265         each VNFD that points to one of our
 266         data center objects known to the gatekeeper.
 267         """
 268         assert(len(self.vnfds) > 0)
 269         assert(len(GK.dcs) > 0)
 270         # instantiate algorithm an place
 271         p = algorithm()
 272         p.place(self.nsd, self.vnfds, GK.dcs)
 273         LOG.info("Using placement algorithm: %r" % p.__class__.__name__)
 274         # lets print the placement result
 275         for name, vnfd in self.vnfds.iteritems():
 276             LOG.info("Placed VNF %r on DC %r" % (name, str(vnfd.get("dc"))))
 277
 278
 279 """
 280 Some (simple) placement algorithms
 281 """
 282
 283
 284 class FirstDcPlacement(object):
 285     """
 286     Placement: Always use one and the same data center from the GK.dcs dict.
 287     """
 288     def place(self, nsd, vnfds, dcs):
 289         for name, vnfd in vnfds.iteritems():
 290             vnfd["dc"] = list(dcs.itervalues())[0]
 291
 292
 293 """
 294 Resource definitions and API endpoints
 295 """
 296
 297
 298 class Packages(fr.Resource):
 299
 300     def post(self):
 301         """
 302         Upload a *.son service package to the dummy gatekeeper.
 303
 304         We expect request with a *.son file and store it in UPLOAD_FOLDER
 305         :return: UUID
 306         """
 307         try:
 308             # get file contents
 309             print(request.files)
 310             # lets search for the package in the request
 311             if "package" in request.files:
 312                 son_file = request.files["package"]
 313             # elif "file" in request.files:
 314             #     son_file = request.files["file"]
 315             else:
 316                 return {"service_uuid": None, "size": 0, "sha1": None, "error": "upload failed. file not found."}, 500
 317             # generate a uuid to reference this package
 318             service_uuid = str(uuid.uuid4())
 319             file_hash = hashlib.sha1(str(son_file)).hexdigest()
 320             # ensure that upload folder exists
 321             ensure_dir(UPLOAD_FOLDER)
 322             upload_path = os.path.join(UPLOAD_FOLDER, "%s.son" % service_uuid)
 323             # store *.son file to disk
 324             son_file.save(upload_path)
 325             size = os.path.getsize(upload_path)
 326             # create a service object and register it
 327             s = Service(service_uuid, file_hash, upload_path)
 328             GK.register_service_package(service_uuid, s)
 329             # generate the JSON result
 330             return {"service_uuid": service_uuid, "size": size, "sha1": file_hash, "error": None}
 331         except Exception as ex:
 332             LOG.exception("Service package upload failed:")
 333             return {"service_uuid": None, "size": 0, "sha1": None, "error": "upload failed"}, 500
 334
 335     def get(self):
 336         """
 337         Return a list of UUID's of uploaded service packages.
 338         :return: dict/list
 339         """
 340         return {"service_uuid_list": list(GK.services.iterkeys())}
 341
 342
 343 class Instantiations(fr.Resource):
 344
 345     def post(self):
 346         """
 347         Instantiate a service specified by its UUID.
 348         Will return a new UUID to identify the running service instance.
 349         :return: UUID
 350         """
 351         # try to extract the service uuid from the request
 352         json_data = request.get_json(force=True)
 353         service_uuid = json_data.get("service_uuid")
 354
 355         # lets be a bit fuzzy here to make testing easier
 356         if service_uuid is None and len(GK.services) > 0:
 357             # if we don't get a service uuid, we simple start the first service in the list
 358             service_uuid = list(GK.services.iterkeys())[0]
 359
 360         if service_uuid in GK.services:
 361             # ok, we have a service uuid, lets start the service
 362             service_instance_uuid = GK.services.get(service_uuid).start_service()
 363             return {"service_instance_uuid": service_instance_uuid}
 364         return "Service not found", 404
 365
 366     def get(self):
 367         """
 368         Returns a list of UUIDs containing all running services.
 369         :return: dict / list
 370         """
 371         return {"service_instance_list": [
 372             list(s.instances.iterkeys()) for s in GK.services.itervalues()]}
 373
 374
 375 # create a single, global GK object
 376 GK = Gatekeeper()
 377 # setup Flask
 378 app = Flask(__name__)
 379 app.config['MAX_CONTENT_LENGTH'] = 512 * 1024 * 1024  # 512 MB max upload
 380 api = fr.Api(app)
 381 # define endpoints
 382 api.add_resource(Packages, '/packages')
 383 api.add_resource(Instantiations, '/instantiations')
 384
 385
 386 def start_rest_api(host, port, datacenters=dict()):
 387     GK.dcs = datacenters
 388     # start the Flask server (not the best performance but ok for our use case)
 389     app.run(host=host,
 390             port=port,
 391             debug=True,
 392             use_reloader=False  # this is needed to run Flask in a non-main thread
 393             )
 394
 395
 396 def ensure_dir(name):
 397     if not os.path.exists(name):
 398         os.makedirs(name)
 399
 400
 401 def load_yaml(path):
 402     with open(path, "r") as f:
 403         try:
 404             r = yaml.load(f)
 405         except yaml.YAMLError as exc:
 406             LOG.exception("YAML parse error")
 407             r = dict()
 408     return r
 409
 410
 411 def make_relative_path(path):
 412     if path.startswith("file://"):
 413         path = path.replace("file://", "", 1)
 414     if path.startswith("/"):
 415         path = path.replace("/", "", 1)
 416     return path
 417
 418
 419 if __name__ == '__main__':
 420     """
 421     Lets allow to run the API in standalone mode.
 422     """
 423     GK_STANDALONE_MODE = True
 424     logging.getLogger("werkzeug").setLevel(logging.INFO)
 425     start_rest_api("0.0.0.0", 8000)
 426