use StreamingHttpResponse instead of Response

use IgnoreClientContentNegotiation for text/event-stream

use Streaming instead of Stream

set Streaming state as early as possible

5 files changed, 49 insertions, 21 deletions

diff --git a/blocks/simulationAPI/helpers/ngspice_helper.py b/blocks/simulationAPI/helpers/ngspice_helper.py
index 12e68cb7..7f1f5185 100644
--- a/blocks/simulationAPI/helpers/ngspice_helper.py
+++ b/blocks/simulationAPI/helpers/ngspice_helper.py
@@ -2,6 +2,7 @@ import os
 import logging
 import re
 import subprocess
+from celery import current_task
 from datetime import datetime
 from pathlib import Path
 from tempfile import mkstemp
@@ -75,6 +76,10 @@ def ExecXml(filepath, file_id, parameters):
 
         os.close(LOGFILEFD)
 
+        current_task.update_state(
+            state='STREAMING',
+            meta={'current_process': 'Processed Xml, Streaming Output'})
+
         cmd = "try;"
         cmd += "chdir('%s');" % current_dir
         cmd += "loadXcosLibs();"
@@ -102,7 +107,7 @@ def ExecXml(filepath, file_id, parameters):
                 logger.info('err=%s', err)
 
         log_name = '/tmp/blocks-tmp/scilab-log.txt' # FIXME: remove this line
-        return ('Success', log_name, proc.returncode)
+        return ('Streaming', log_name, proc.returncode)
     except BaseException as e:
         logger.exception('Encountered Exception:')
         logger.info('removing %s', filepath)
diff --git a/blocks/simulationAPI/negotiation.py b/blocks/simulationAPI/negotiation.py
new file mode 100644
index 00000000..c94f0ac5
--- /dev/null
+++ b/blocks/simulationAPI/negotiation.py
@@ -0,0 +1,14 @@
+from rest_framework.negotiation import BaseContentNegotiation
+
+class IgnoreClientContentNegotiation(BaseContentNegotiation):
+    def select_parser(self, request, parsers):
+        """
+        Select the first parser in the `.parser_classes` list.
+        """
+        return parsers[0]
+
+    def select_renderer(self, request, renderers, format_suffix):
+        """
+        Select the first renderer in the `.renderer_classes` list.
+        """
+        return (renderers[0], renderers[0].media_type)
diff --git a/blocks/simulationAPI/tasks.py b/blocks/simulationAPI/tasks.py
index f3c4891c..9ec1c4ea 100644
--- a/blocks/simulationAPI/tasks.py
+++ b/blocks/simulationAPI/tasks.py
@@ -1,11 +1,11 @@
-import json
-from celery import shared_task, current_task
-from celery import states
-from simulationAPI.helpers import ngspice_helper
+from celery import shared_task, current_task, states
 from celery.exceptions import Ignore
+import json
+import logging
 import traceback
+
+from simulationAPI.helpers import ngspice_helper
 from simulationAPI.models import TaskFile
-import logging
 
 
 logger = logging.getLogger(__name__)
@@ -28,13 +28,18 @@ def process_task(task_id):
             meta={'current_process': 'Started Processing File'})
 
         output = ngspice_helper.ExecXml(file_path, file_id, parameters)
-        if output[0] == "Success":
+        if output[0] == "Streaming":
             file_obj.log_name = output[1]
             file_obj.returncode = output[2]
             file_obj.save()
+            state = 'STREAMING'
+            current_process = 'Processed Xml, Streaming Output'
+        elif output[0] == "Success":
+            state = 'SUCCESS'
+            current_process = 'Processed Xml, Loading Output'
         current_task.update_state(
-            state='STREAM',
-            meta={'current_process': 'Processed Xml, Streaming Output'})
+            state=state,
+            meta={'current_process': current_process})
         return output[0]
 
     except Exception as e:
diff --git a/blocks/simulationAPI/urls.py b/blocks/simulationAPI/urls.py
index f03380d1..f19eddc1 100644
--- a/blocks/simulationAPI/urls.py
+++ b/blocks/simulationAPI/urls.py
@@ -9,6 +9,6 @@ urlpatterns = [
     path('status/<uuid:task_id>',
          simulationAPI_views.CeleryResultView.as_view(), name='celery_status'),
 
-    path('stream/<uuid:task_id>',
+    path('streaming/<uuid:task_id>',
          simulationAPI_views.StreamView.as_view(), name='stream_status'),
 ]
diff --git a/blocks/simulationAPI/views.py b/blocks/simulationAPI/views.py
index 7894a1b6..11261352 100644
--- a/blocks/simulationAPI/views.py
+++ b/blocks/simulationAPI/views.py
@@ -1,17 +1,20 @@
-from simulationAPI.models import TaskFile
-from simulationAPI.serializers import TaskSerializer
-from simulationAPI.tasks import process_task
+import logging
+import os
+import time
+import uuid
+from celery.result import AsyncResult
+from django.http import StreamingHttpResponse
 from rest_framework import status
 from rest_framework.exceptions import ValidationError
 from rest_framework.parsers import MultiPartParser, FormParser
 from rest_framework.permissions import AllowAny
-from rest_framework.views import APIView
 from rest_framework.response import Response
-from celery.result import AsyncResult
-import os
-import uuid
-import logging
-import time
+from rest_framework.views import APIView
+
+from simulationAPI.models import TaskFile
+from simulationAPI.negotiation import IgnoreClientContentNegotiation
+from simulationAPI.serializers import TaskSerializer
+from simulationAPI.tasks import process_task
 
 
 SCILAB_INSTANCE_TIMEOUT_INTERVAL = 300
@@ -152,14 +155,15 @@ class StreamView(APIView):
 
     Streams Simulation results for 'task_id' provided after
     uploading the xml
-    /api/stream/<uuid>
+    /api/streaming/<uuid>
 
     """
     permission_classes = (AllowAny,)
     methods = ['GET']
+    content_negotiation_class = IgnoreClientContentNegotiation
 
     def get(self, request, task_id):
-        return Response(self.event_stream(task_id), content_type='text/event-stream')
+        return StreamingHttpResponse(self.event_stream(task_id), content_type='text/event-stream')
 
     def get_log_name(self, task_id):
         while True: