http client class

capsulflask/http_client.py

@@ -0,0 +1,69 @@
+
+import sys
+import json
+
+import aiohttp
+import asyncio
+from flask import current_app
+from capsulflask.db import  my_exec_info_message
+from capsulflask.db_model import OnlineHost
+from typing import List
+
+class HTTPResult:
+  def __init__(self, status_code, body=None):
+    self.status_code = status_code
+    self.body = body
+
+class MyHTTPClient:
+  def __init__(self, timeout_seconds = 5):
+    self.client_session = aiohttp.ClientSession(timeout=aiohttp.ClientTimeout(total=timeout_seconds))
+    self.event_loop = asyncio.get_event_loop()
+
+  def make_requests_sync(self, online_hosts: List[OnlineHost], body: str) -> List(HTTPResult):
+    self.event_loop.run_until_complete(self.make_requests(online_hosts=online_hosts, body=body))
+
+  def post_json_sync(self, method: str, url: str,  body: str) -> HTTPResult:
+      self.event_loop.run_until_complete(self.post_json_sync(method=method, url=url, body=body))
+
+  async def post_json(self, method: str, url: str,  body: str) -> HTTPResult:
+    response = None
+    try:
+      response = await self.client_session.request(
+        method=method, 
+        url=url, 
+        json=body, 
+        auth=aiohttp.BasicAuth("hub", current_app.config['HUB_TOKEN']), 
+        verify_ssl=True,
+      )
+    except:
+      error_message = my_exec_info_message(sys.exc_info())
+      response_body = json.dumps({"error_message": f"error contacting spoke: {error_message}"})
+      current_app.logger.error(f"""
+        error contacting spoke: post_json (HTTP {method} {url}) failed with: {error_message}"""
+      )
+      return HTTPResult(-1, response_body)
+
+    response_body = None
+    try:
+      response_body = await response.text()
+    except:
+      error_message = my_exec_info_message(sys.exc_info())
+      response_body = json.dumps({"error_message": f"error reading response from spoke: {error_message}"})
+      current_app.logger.error(f"""
+        error reading response from spoke: HTTP {method} {url} (status {response.status}) failed with: {error_message}"""
+      )
+      
+    return HTTPResult(response.status, response_body)
+
+  async def make_requests(self, online_hosts: List[OnlineHost], body: str) -> List(HTTPResult):
+    tasks = []
+    # append to tasks in the same order as online_hosts
+    for host in online_hosts:
+        tasks.append(
+            self.post_json(method="POST", url=host.url, body=body)
+        )
+    # gather is like Promise.all from javascript, it returns a future which resolves to an array of results 
+    # in the same order as the tasks that we passed in -- which were in the same order as online_hosts
+    results = await asyncio.gather(*tasks)
+
+    return results