From 17c2fe68f2cf53c1ead0169aa07082c9b07f2a6e Mon Sep 17 00:00:00 2001
From: David Wilson <dw@botanicus.net>
Date: Thu, 24 Aug 2017 15:56:55 +0530
Subject: [PATCH] Add Router.enable_debug() rather than cutpasting snippets
 constantly.

---
 econtext/core.py   | 26 +++++++++++++++++++++-----
 econtext/master.py | 19 ++++++++++++++++++-
 2 files changed, 39 insertions(+), 6 deletions(-)

diff --git a/econtext/core.py b/econtext/core.py
index cce2b2e4..8f99528a 100644
--- a/econtext/core.py
+++ b/econtext/core.py
@@ -101,6 +101,20 @@ def set_cloexec(fd):
     fcntl.fcntl(fd, fcntl.F_SETFD, flags | fcntl.FD_CLOEXEC)
 
 
+def enable_debug_logging():
+    root = logging.getLogger()
+    root.setLevel(logging.DEBUG)
+    IOLOG.setLevel(logging.DEBUG)
+    fp = open('/tmp/econtext.%s.log' % (os.getpid(),), 'w', 1)
+    set_cloexec(fp.fileno())
+    handler = logging.StreamHandler(fp)
+    handler.formatter = logging.Formatter(
+        '%(asctime)s %(levelname).1s %(name)s: %(message)s',
+        '%H:%M:%S'
+    )
+    root.handlers.insert(0, handler)
+
+
 class Message(object):
     dst_id = None
     src_id = None
@@ -946,11 +960,12 @@ class ExternalContext(object):
         os.wait()  # Reap first stage.
         os.close(100)
 
-    def _setup_logging(self, log_level):
-        logging.basicConfig(level=log_level)
+    def _setup_logging(self, debug, log_level):
         root = logging.getLogger()
         root.setLevel(log_level)
         root.handlers = [LogHandler(self.context)]
+        if debug:
+            enable_debug_logging()
 
     def _setup_importer(self):
         with os.fdopen(101, 'r', 1) as fp:
@@ -1008,15 +1023,16 @@ class ExternalContext(object):
                 e = CallError(str(e))
                 self.context.send(Message.pickled(e, handle=msg.reply_to))
 
-    def main(self, parent_id, context_id, key, log_level):
+    def main(self, parent_id, context_id, key, debug, log_level):
         self._setup_master(parent_id, context_id, key)
         try:
             try:
-                self._setup_logging(log_level)
+                self._setup_logging(debug, log_level)
                 self._setup_importer()
                 self._setup_package(context_id)
                 self._setup_stdio()
-                LOG.debug('Connected to %s; my ID is %r', self.context, context_id)
+                LOG.debug('Connected to %s; my ID is %r, PID is %r',
+                          self.context, context_id, os.getpid())
 
                 self.router.register(self.context, self.stream)
                 self._dispatch_calls()
diff --git a/econtext/master.py b/econtext/master.py
index d2d457f3..a4e8769c 100644
--- a/econtext/master.py
+++ b/econtext/master.py
@@ -326,7 +326,10 @@ class Stream(econtext.core.Stream):
     #: The path to the remote Python interpreter.
     python_path = 'python2.7'
 
-    def construct(self, remote_name=None, python_path=None, **kwargs):
+    #: True to cause context to write verbose /tmp/econtext.<pid>.log.
+    debug = False
+
+    def construct(self, remote_name=None, python_path=None, debug=False, **kwargs):
         """Get the named context running on the local machine, creating it if
         it does not exist."""
         super(Stream, self).construct(**kwargs)
@@ -338,6 +341,7 @@ class Stream(econtext.core.Stream):
             remote_name %= (getpass.getuser(), socket.gethostname(), os.getpid())
         self.remote_name = remote_name
         self.name = 'local.default'
+        self.debug = debug
 
     def on_shutdown(self, broker):
         """Request the slave gracefully shut itself down."""
@@ -388,6 +392,7 @@ class Stream(econtext.core.Stream):
             0,
             self.remote_id,            # context_id
             self.key,
+            self.debug,
             LOG.level or logging.getLogger().level or logging.INFO,
         ),)
 
@@ -506,7 +511,19 @@ class Router(econtext.core.Router):
         import econtext.ssh
         return self.connect(econtext.ssh.Stream, **kwargs)
 
+    debug = False
+
+    def enable_debug(self):
+        """
+        Cause this context and any descendant child contexts to write debug
+        logs to /tmp/econtext.<pid>.log.
+        """
+        econtext.core.enable_debug_logging()
+        self.debug = True
+
     def connect(self, klass, name=None, **kwargs):
+        kwargs.setdefault('debug', self.debug)
+
         via = kwargs.pop('via', None)
         if via is not None:
             return self.proxy_connect(via, klass, name=name, **kwargs)