[CORD-2930] Pulling OLT Devices from VOLTHA

Change-Id: Ieb28b92da3c67b4fc562d42e29b0e58aec6d7be9
diff --git a/xos/synchronizer/pull_steps/pull_olts.py b/xos/synchronizer/pull_steps/pull_olts.py
index 3ab76e0..e377f1b 100644
--- a/xos/synchronizer/pull_steps/pull_olts.py
+++ b/xos/synchronizer/pull_steps/pull_olts.py
@@ -13,16 +13,151 @@
 # limitations under the License.
 
 from synchronizers.new_base.pullstep import PullStep
-from synchronizers.new_base.modelaccessor import OLTDevice
+from synchronizers.new_base.modelaccessor import model_accessor, OLTDevice, VOLTService
 
 from xosconfig import Config
 from multistructlog import create_logger
 
+import requests
+from requests import ConnectionError
+from requests.models import InvalidURL
+
 log = create_logger(Config().get('logging'))
 
 class OLTDevicePullStep(PullStep):
     def __init__(self):
         super(OLTDevicePullStep, self).__init__(observed_model=OLTDevice)
 
+    # NOTE move helpers where they can be loaded by multiple modules?
+    @staticmethod
+    def format_url(url):
+        if 'http' in url:
+            return url
+        else:
+            return 'http://%s' % url
+
+    @staticmethod
+    def get_voltha_info(olt_service):
+        return {
+            'url': OLTDevicePullStep.format_url(olt_service.voltha_url),
+            'user': olt_service.voltha_user,
+            'pass': olt_service.voltha_pass
+        }
+
+    @staticmethod
+    def datapath_id_to_hex(id):
+        if isinstance(id, basestring):
+            id = int(id)
+        return "{0:0{1}x}".format(id, 16)
+
+    @staticmethod
+    def get_ids_from_logical_device(o):
+        voltha_url = OLTDevicePullStep.get_voltha_info(o.volt_service)['url']
+
+        r = requests.get(voltha_url + "/api/v1/logical_devices")
+
+        if r.status_code != 200:
+            raise Exception("Failed to retrieve logical devices from VOLTHA: %s" % r.text)
+
+        res = r.json()
+
+        for ld in res["items"]:
+            if ld["root_device_id"] == o.device_id:
+                o.of_id = ld["id"]
+                o.dp_id = "of:" + OLTDevicePullStep.datapath_id_to_hex(ld["datapath_id"])  # convert to hex
+                return o
+
+        raise Exception("Can't find a logical device for device id: %s" % o.device_id)
+    # end note
+
     def pull_records(self):
         log.info("pulling OLT devices from VOLTHA")
+
+        try:
+            self.volt_service = VOLTService.objects.all()[0]
+        except IndexError:
+            log.warn('VOLTService not found')
+            return
+
+        voltha_url = OLTDevicePullStep.get_voltha_info(self.volt_service)['url']
+
+        try:
+            devices = []
+            r = requests.get(voltha_url + "/api/v1/devices")
+
+            if r.status_code != 200:
+                log.info("It was not possible to fetch devices from VOLTHA")
+
+            # keeping only OLTs
+            devices = [d for d in r.json()["items"] if "olt" in d["type"]]
+
+            log.debug("received devices", olts=devices)
+
+            # TODO
+            # [X] for each device
+            # [X] check if exists, if not save it
+            # [X] if exists and enacted > updated it has already been sync'ed
+            # [X] keep track of the updated OLTs
+            # delete OLTS as OLTDevice.objects.all() - updated OLTs
+
+            if r.status_code != 200:
+                log.info("It was not possible to fetch devices from VOLTHA")
+
+            olts_in_voltha = self.create_or_update_olts(devices)
+
+        except ConnectionError, e:
+            log.warn("It was not possible to connect to VOLTHA", reason=e)
+            return
+        except InvalidURL, e:
+            log.warn("VOLTHA url is invalid, is it configured in the VOLTService?", reason=e)
+            return
+
+    def create_or_update_olts(self, olts):
+
+        updated_olts = []
+
+        for olt in olts:
+            try:
+                if olt["type"] == "simulated_olt":
+                    [host, port] = ["172.17.0.1", "50060"]
+                else:
+                    [host, port] = olt["host_and_port"].split(":")
+                model = OLTDevice.objects.filter(device_type=olt["type"], host=host, port=port)[0]
+                log.debug("OLTDevice already exists, updating it", device_type=olt["type"], host=host, port=port)
+
+                if model.enacted < model.updated:
+                    log.info("Skipping pull on OLTDevice %s as enacted < updated" % model.name, name=model.name, id=model.id, enacted=model.enacted, updated=model.updated)
+                    return
+
+            except IndexError:
+                model = OLTDevice()
+                model.device_type = olt["type"]
+
+                if olt["type"] == "simulated_olt":
+                    model.host = "172.17.0.1"
+                    model.port = 50060
+
+                log.debug("OLTDevice is new, creating it", device_type=olt["type"], host=host, port=port)
+
+            # Adding feedback state to the device
+            model.device_id = olt["id"]
+            model.admin_state = olt["admin_state"]
+            model.oper_status = olt["oper_status"]
+
+            model.volt_service = self.volt_service
+            model.volt_service_id = self.volt_service.id
+
+            # get logical device
+            OLTDevicePullStep.get_ids_from_logical_device(model)
+
+            model.save()
+
+            updated_olts.append(model)
+
+        return updated_olts
+
+
+
+
+
+