@@ -28,10 +28,16 @@ class ITutorialDKernel(Kernel):
2828 port = 63000
2929 dbname = 'jupyter'
3030 if not self.dbserver:
31− self.dbserver = subprocess.Popen(['project-m36-websocket-server',
32− '--database', dbname,
33− '--port', str(port)],
34− )
31+ try:
32+ self.dbserver = subprocess.Popen(['project-m36-websocket-server',
33+ '--database', dbname,
34+ '--port', str(port)],
35+ )
36+ except OSError as err:
37+ if err.errno == errno.ENOENT:
38+ return ({'displayerror':{'html':'"project-m36-websocket-server" is not in the PATH environment variable and could not be started.'}}, None)
39+ else:
40+ raise
3541 if not self.ws:
3642 attempts = 0
3743 while 1:
@@ -72,6 +78,13 @@ class ITutorialDKernel(Kernel):
7278 if 'promptInfo' not in msg:
7379 return msg
7480
81+ def send_error(self, msg):
82+ stream_content = {'ename':'TutorialDError',
83+ 'traceback':[msg],
84+ 'evalue':''}
85+ self.send_response(self.iopub_socket, 'error', stream_content)
86+
87+
7588 def do_execute(self, code, silent,
7689 store_history=True,
7790 user_expressions=False,
@@ -80,11 +93,7 @@ class ITutorialDKernel(Kernel):
8093 if not silent:
8194 if err:
8295 status = 'error'
83− stream_content = {'ename':'TutorialDError',
84− 'traceback':[err['displayerror']['html']],
85− 'ename':'TutorialDError',
86− 'evalue':''}
87− self.send_response(self.iopub_socket, 'error', stream_content)
96+ self.send_error(err['displayerror']['html'])
8897 else:
8998 status = 'ok'
9099 display_content = {