component/opcua-server: notify erp5 if datachange

component/opcua-server/buildout.cfg

@@ -3,7 +3,10 @@ parts = opcua-server
 
 [opcua-server]
 recipe = zc.recipe.egg
-eggs = asyncua
+eggs =
+  asyncua
+# To send data to erp5
+  requests
 egg-versions =
   asyncua = 1.0.1
   sortedcontainers = 2.4.0
@@ -12,27 +15,44 @@ egg-versions =
   python-dateutil = 2.8.2:whl
 entry-points = ${:_buildout_section_name_}=__main__:main
 initialization =
-  # ######################
+  # #################################
   # Configure
   import argparse
   parser = argparse.ArgumentParser(description='Run OPCUA Server.')
-  parser.add_argument(
-    '--ip', help='The IP address on which the OPCUA Server runs', default="127.0.0.1"
-  )
-  parser.add_argument(
-    '--port', help='The port on which the OPCUA Server runs', default="2262"
-  )
-  parser.add_argument(
-    '--xml',
-    help='Path of XML to configure Server. See asyncua doc for more details.',
-    default=None
-  )
+  a = parser.add_argument
+  a('--ip', help='The IP address on which the OPCUA Server runs', default="127.0.0.1")
+  a('--port', help='The port on which the OPCUA Server runs', default="2262")
+  a('--xml', help='Path of XML to configure Server. See asyncua doc for more details.', default=None)
+  a('--erp5-ip', help='IP of ERP5 instance to which data shall be send.', default=None)
+  a('--erp5-port', help='Port of ERP5 instance to which data shall be send.', default=None)
   args = parser.parse_args()
-  ip, port, xml = args.ip, args.port, args.xml
-  # ######################
+  ip, port, xml, erp5_ip, erp5_port = args.ip, args.port, args.xml, args.erp5_ip, args.erp5_port
+  # #################################
+  # Define ERP5Handler
+  from dataclasses import dataclass, field
+  import json
+  import requests
+  import urllib
+  from asyncua.common.subscription import SubHandler
+  @dataclass(frozen=True)
+  class ERP5Handler(SubHandler):
+    ip: str
+    port: str
+    session: requests.Session = field(default_factory=requests.Session)
+    @property
+    def uri(self):
+      return f"http://{self.ip}:{self.port}/erp5/opcua_test"
+    def call(self, **data):
+      params = urllib.parse.quote_plus(json.dumps({k: str(v) for k, v in data.items()}))
+      self.session.post(f"{self.uri}?data={params}")
+    def datachange_notification(self, node, val, data):
+      self.call(node=node, val=val, data=data)
+  # #################################
+  # Start OPCUA Server
   import asyncio
   import logging
   from asyncua import Server
+  from asyncua.common.ua_utils import get_nodes_of_namespace
   async def main():
     _logger = logging.getLogger(__name__)
     # setup our server
@@ -41,6 +61,13 @@ initialization =
     server.set_endpoint(f"opc.tcp://{ip}:{port}/freeopcua/server/")
     if xml is not None:
       await server.import_xml(xml)
+    if erp5_ip is not None and erp5_port is not None:
+      erp5_handler = ERP5Handler(erp5_ip, erp5_port)
+      subscription = await server.create_subscription(1000, erp5_handler)
+      await subscription.subscribe_events()
+      nodes = await get_nodes_of_namespace(server)
+      await subscription.subscribe_data_change(nodes)
+      _logger.info("Added subscription for erp5 handler.")
     _logger.info("Starting server!")
     async with server:
       while True:

stack/erp5/instance-opcua-server.cfg.in

@@ -2,6 +2,9 @@
 {# port is hard coded here + in stack/erp5/haproxy.cfg.in #}
 {% set port = 2262 %}
 {% set opcua_server_config = parameter_dict["opcua_server_config_xml"] %}
+{# erp5 port hard coded for now. #}
+{# see https://lab.nexedi.com/nexedi/slapos/blob/a729a677/stack/erp5/instance-erp5.cfg.in#L310 #}
+{% set erp5_port = "2200" %}
 
 [buildout]
 extends = {{ template_monitor }}
@@ -22,5 +25,5 @@ var = ${buildout:directory}/var
 [opcua-server]
 recipe = slapos.cookbook:wrapper
 command-line =
-  {{ bin_directory }}/opcua-server  --ip {{ ipv4 }} --port {{ port }} --xml {{ opcua_server_config }}
+  {{ bin_directory }}/opcua-server  --ip {{ ipv4 }} --port {{ port }} --xml {{ opcua_server_config }} --erp5-ip {{ ipv4 }} --erp5-port {{ erp5_port }}
 wrapper-path = ${directory:service-on-watch}/opcua-server