Maint/asyncio (#305)

* Move to asyncio services, even though everything is largely sync

trustgraph-base/trustgraph/base/base_processor.py

@@ -1,4 +1,5 @@
 
+import asyncio
 import os
 import argparse
 import pulsar
@@ -83,11 +84,20 @@ class BaseProcessor:
             help=f'Pulsar host (default: 8000)',
         )
 
-    def run(self):
+    async def start(self):
+        pass
+
+    async def run(self):
         raise RuntimeError("Something should have implemented the run method")
 
     @classmethod
-    def start(cls, prog, doc):
+    async def launch_async(cls, args):
+        p = cls(**args)
+        await p.start()
+        await p.run()
+
+    @classmethod
+    def launch(cls, prog, doc):
 
         parser = argparse.ArgumentParser(
             prog=prog,
@@ -108,8 +118,7 @@ class BaseProcessor:
 
             try:
 
-                p = cls(**args)
-                p.run()
+                asyncio.run(cls.launch_async(args))
 
             except KeyboardInterrupt:
                 print("Keyboard interrupt.")
@@ -127,3 +136,4 @@ class BaseProcessor:
                 print("Will retry...", flush=True)
 
                 time.sleep(4)
+

trustgraph-base/trustgraph/base/consumer.py

@@ -1,4 +1,5 @@
 
+import asyncio
 from pulsar.schema import JsonSchema
 import pulsar
 from prometheus_client import Histogram, Info, Counter, Enum
@@ -75,7 +76,7 @@ class Consumer(BaseProcessor):
 
         print("Initialised consumer.", flush=True)
 
-    def run(self):
+    async def run(self):
 
         __class__.state_metric.state('running')
 
@@ -104,7 +105,7 @@ class Consumer(BaseProcessor):
                 try:
 
                     with __class__.request_metric.time():
-                        self.handle(msg)
+                        await self.handle(msg)
 
                     # Acknowledge successful processing of the message
                     self.consumer.acknowledge(msg)

trustgraph-base/trustgraph/base/consumer_producer.py

@@ -42,7 +42,7 @@ class ConsumerProducer(Consumer):
 
         print("Initialised consumer/producer.")
 
-    def send(self, msg, properties={}):
+    async def send(self, msg, properties={}):
         self.producer.send(msg, properties)
         __class__.output_metric.inc()
 

trustgraph-base/trustgraph/base/producer.py

@@ -37,7 +37,7 @@ class Producer(BaseProcessor):
             chunking_enabled=True,
         )
 
-    def send(self, msg, properties={}):
+    async def send(self, msg, properties={}):
         self.producer.send(msg, properties)
         __class__.output_metric.inc()