Merge pull request curveresearch#61 from curveresearch/notebook-fix

Notebook fix

curvesim/network/utils.py

@@ -1,4 +1,6 @@
 import asyncio
+import functools
+from concurrent.futures import ThreadPoolExecutor
 
 from gmpy2 import mpz
 
@@ -24,6 +26,19 @@ def compute_D(xp, A):
     return D
 
 
+# "extra" event loop for special but important use-cases,
+# such as running inside a Jupyter Notebook, which already
+# runs an event loop for "convenient" await syntax.
+_loop = None
+
+
+def _setupExtraEventLoop():
+    """Sets up the extra event loop for scheduling."""
+    global _loop
+    _loop = asyncio.new_event_loop()
+    ThreadPoolExecutor().submit(_loop.run_forever)
+
+
 def sync(func):
     """
     Returns a sync version of an async function.
@@ -39,9 +54,22 @@ def sync(func):
         Sync version of the async function.
     """
 
+    @functools.wraps(func)
     def inner(*args, event_loop=None, **kwargs):
         loop = event_loop or asyncio.get_event_loop()
-        res = loop.run_until_complete(func(*args, **kwargs))
+        coro = func(*args, **kwargs)
+        if loop.is_running():
+            # If for some reason, we are trying to make async code
+            # synchronous inside a running event loop, we are
+            # probably in something like a Jupyter notebook.
+            if not _loop:
+                _setupExtraEventLoop()
+            future = asyncio.run_coroutine_threadsafe(coro, _loop)
+            res = future.result()
+
+        else:
+            res = loop.run_until_complete(coro)
+
         return res
 
     return inner