From 6931d8e58642c5d7f45ab1dcf3f8de012b66e20c Mon Sep 17 00:00:00 2001
From: Jack Robison <jackrobison@lbry.io>
Date: Wed, 10 May 2017 01:23:42 -0400
Subject: [PATCH] decorator for queued api commands

---
 lbrynet/lbrynet_daemon/Daemon.py      |  2 ++
 lbrynet/lbrynet_daemon/auth/server.py | 32 ++++++++++++++++++++++++++-
 2 files changed, 33 insertions(+), 1 deletion(-)

diff --git a/lbrynet/lbrynet_daemon/Daemon.py b/lbrynet/lbrynet_daemon/Daemon.py
index 2e5a2bef4..f866ea163 100644
--- a/lbrynet/lbrynet_daemon/Daemon.py
+++ b/lbrynet/lbrynet_daemon/Daemon.py
@@ -1681,6 +1681,7 @@ class Daemon(AuthJSONRPCServer):
         defer.returnValue(cost)
 
     @AuthJSONRPCServer.auth_required
+    @AuthJSONRPCServer.queued
     @defer.inlineCallbacks
     def jsonrpc_channel_new(self, channel_name, amount):
         """
@@ -1735,6 +1736,7 @@ class Daemon(AuthJSONRPCServer):
         defer.returnValue(response)
 
     @AuthJSONRPCServer.auth_required
+    @AuthJSONRPCServer.queued
     @defer.inlineCallbacks
     def jsonrpc_publish(self, name, bid, metadata=None, file_path=None, fee=None, title=None,
                         description=None, author=None, language=None, license=None,
diff --git a/lbrynet/lbrynet_daemon/auth/server.py b/lbrynet/lbrynet_daemon/auth/server.py
index 684b1224c..5f46af3a3 100644
--- a/lbrynet/lbrynet_daemon/auth/server.py
+++ b/lbrynet/lbrynet_daemon/auth/server.py
@@ -114,6 +114,8 @@ class AuthorizedBase(object):
     def __init__(self):
         self.authorized_functions = []
         self.callable_methods = {}
+        self._call_lock = {}
+        self._queued_methods = []
 
         for methodname in dir(self):
             if methodname.startswith("jsonrpc_"):
@@ -121,12 +123,19 @@ class AuthorizedBase(object):
                 self.callable_methods.update({methodname.split("jsonrpc_")[1]: method})
                 if hasattr(method, '_auth_required'):
                     self.authorized_functions.append(methodname.split("jsonrpc_")[1])
+                if hasattr(method, '_queued'):
+                    self._queued_methods.append(methodname.split("jsonrpc_")[1])
 
     @staticmethod
     def auth_required(f):
         f._auth_required = True
         return f
 
+    @staticmethod
+    def queued(f):
+        f._queued = True
+        return f
+
 
 class AuthJSONRPCServer(AuthorizedBase):
     """Authorized JSONRPC server used as the base class for the LBRY API
@@ -254,6 +263,7 @@ class AuthJSONRPCServer(AuthorizedBase):
         id_ = None
         try:
             function_name = parsed.get('method')
+            is_queued = function_name in self._queued_methods
             args = parsed.get('params', {})
             id_ = parsed.get('id', None)
             token = parsed.pop('hmac', None)
@@ -324,7 +334,27 @@ class AuthJSONRPCServer(AuthorizedBase):
             )
             return server.NOT_DONE_YET
 
-        d = defer.maybeDeferred(function, **args_dict)
+        if is_queued:
+            d_lock = self._call_lock.get(function_name, False)
+            if not d_lock:
+                d = defer.maybeDeferred(function, **args_dict)
+                self._call_lock[function_name] = finished_deferred
+
+                def _del_lock(*args):
+                    if function_name in self._call_lock:
+                        del self._call_lock[function_name]
+                    if args:
+                        return args
+
+                finished_deferred.addCallback(_del_lock)
+
+            else:
+                log.info("queued %s", function_name)
+                d = d_lock
+                d.addBoth(lambda _: log.info("running %s from queue", function_name))
+                d.addCallback(lambda _: defer.maybeDeferred(function, **args_dict))
+        else:
+            d = defer.maybeDeferred(function, **args_dict)
 
         # finished_deferred will callback when the request is finished
         # and errback if something went wrong. If the errback is