-
Notifications
You must be signed in to change notification settings - Fork 129
/
gatewayapp.py
490 lines (426 loc) · 18.4 KB
/
gatewayapp.py
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
# Copyright (c) Jupyter Development Team.
# Distributed under the terms of the Modified BSD License.
"""Kernel Gateway Jupyter application."""
import os
import socket
import errno
import logging
import nbformat
try:
from urlparse import urlparse
except ImportError:
from urllib.parse import urlparse
from traitlets import Unicode, Integer, Bool, default
from jupyter_core.application import JupyterApp
from jupyter_client.kernelspec import KernelSpecManager
# Install the pyzmq ioloop. This has to be done before anything else from
# tornado is imported.
from zmq.eventloop import ioloop
ioloop.install()
from tornado import httpserver
from tornado import web
from tornado.log import enable_pretty_logging
from notebook.notebookapp import random_ports
from .services.api.handlers import default_handlers as default_api_handlers
from .services.kernels.handlers import default_handlers as default_kernel_handlers
from .services.kernelspecs.handlers import default_handlers as default_kernelspec_handlers
from .services.sessions.handlers import default_handlers as default_session_handlers
from .services.sessions.sessionmanager import SessionManager
from .services.activity.manager import ActivityManager
from .services.kernels.manager import SeedingMappingKernelManager
from .services.kernels.pool import KernelPool, ManagedKernelPool
from .base.handlers import default_handlers as default_base_handlers
from .services.notebooks.handlers import NotebookAPIHandler, parameterize_path, NotebookDownloadHandler
from .services.cell.parser import APICellParser
from .services.swagger.handlers import SwaggerSpecHandler
from .services.activity.handlers import ActivityHandler
from notebook.utils import url_path_join
class KernelGatewayApp(JupyterApp):
"""Application that provisions Jupyter kernels and proxies HTTP/Websocket
traffic to the kernels.
- reads command line and environment variable settings
- initializes managers and routes
- creates a Tornado HTTP server
- starts the Tornado event loop
"""
name = 'jupyter-kernel-gateway'
description = """
Jupyter Kernel Gateway
Provisions Jupyter kernels and proxies HTTP/Websocket traffic
to them.
"""
# Server IP / PORT binding
port_env = 'KG_PORT'
port = Integer(config=True,
help="Port on which to listen (KG_PORT env var)"
)
@default('port')
def port_default(self):
return int(os.getenv(self.port_env, 8888))
port_retries_env = 'KG_PORT_RETRIES'
port_retries = Integer(config=True,
help="Number of ports to try if the specified port is not available (KG_PORT_RETRIES env var)"
)
@default('port_retries')
def port_retries_default(self):
return int(os.getenv(self.port_retries_env, 50))
ip_env = 'KG_IP'
ip = Unicode(config=True,
help="IP address on which to listen (KG_IP env var)"
)
@default('ip')
def ip_default(self):
return os.getenv(self.ip_env, '127.0.0.1')
# Base URL
base_url_env = 'KG_BASE_URL'
base_url = Unicode(config=True,
help="""The base path for mounting all API resources (KG_BASE_URL env var)""")
@default('base_url')
def base_url_default(self):
return os.getenv(self.base_url_env, '/')
# Token authorization
auth_token_env = 'KG_AUTH_TOKEN'
auth_token = Unicode(config=True,
help='Authorization token required for all requests (KG_AUTH_TOKEN env var)'
)
@default('auth_token')
def _auth_token_default(self):
return os.getenv(self.auth_token_env, '')
# CORS headers
allow_credentials_env = 'KG_ALLOW_CREDENTIALS'
allow_credentials = Unicode(config=True,
help='Sets the Access-Control-Allow-Credentials header. (KG_ALLOW_CREDENTIALS env var)'
)
@default('allow_credentials')
def allow_credentials_default(self):
return os.getenv(self.allow_credentials_env, '')
allow_headers_env = 'KG_ALLOW_HEADERS'
allow_headers = Unicode(config=True,
help='Sets the Access-Control-Allow-Headers header. (KG_ALLOW_HEADERS env var)'
)
@default('allow_headers')
def allow_headers_default(self):
return os.getenv(self.allow_headers_env, '')
allow_methods_env = 'KG_ALLOW_METHODS'
allow_methods = Unicode(config=True,
help='Sets the Access-Control-Allow-Methods header. (KG_ALLOW_METHODS env var)'
)
@default('allow_methods')
def allow_methods_default(self):
return os.getenv(self.allow_methods_env, '')
allow_origin_env = 'KG_ALLOW_ORIGIN'
allow_origin = Unicode(config=True,
help='Sets the Access-Control-Allow-Origin header. (KG_ALLOW_ORIGIN env var)'
)
@default('allow_origin')
def allow_origin_default(self):
return os.getenv(self.allow_origin_env, '')
expose_headers_env = 'KG_EXPOSE_HEADERS'
expose_headers = Unicode(config=True,
help='Sets the Access-Control-Expose-Headers header. (KG_EXPOSE_HEADERS env var)'
)
@default('expose_headers')
def expose_headers_default(self):
return os.getenv(self.expose_headers_env, '')
max_age_env = 'KG_MAX_AGE'
max_age = Unicode(config=True,
help='Sets the Access-Control-Max-Age header. (KG_MAX_AGE env var)'
)
@default('max_age')
def max_age_default(self):
return os.getenv(self.max_age_env, '')
max_kernels_env = 'KG_MAX_KERNELS'
max_kernels = Integer(config=True,
allow_none=True,
help='Limits the number of kernel instances allowed to run by this gateway. (KG_MAX_KERNELS env var)'
)
@default('max_kernels')
def max_kernels_default(self):
val = os.getenv(self.max_kernels_env)
return val if val is None else int(val)
seed_uri_env = 'KG_SEED_URI'
seed_uri = Unicode(config=True,
allow_none=True,
help='Runs the notebook (.ipynb) at the given URI on every kernel launched. (KG_SEED_URI env var)'
)
@default('seed_uri')
def seed_uri_default(self):
return os.getenv(self.seed_uri_env)
prespawn_count_env = 'KG_PRESPAWN_COUNT'
prespawn_count = Integer(config=True,
default_value=None,
allow_none=True,
help='Number of kernels to prespawn using the default language. (KG_PRESPAWN_COUNT env var)'
)
@default('prespawn_count')
def prespawn_count_default(self):
val = os.getenv(self.prespawn_count_env)
return val if val is None else int(val)
default_kernel_name_env = 'KG_DEFAULT_KERNEL_NAME'
default_kernel_name = Unicode(config=True,
help="""The default kernel name when spawning a kernel (KG_DEFAULT_KERNEL_NAME env var)""")
@default('default_kernel_name')
def default_kernel_name_default(self):
# defaults to Jupyter's default kernel name on empty string
return os.getenv(self.default_kernel_name_env, '')
list_kernels_env = 'KG_LIST_KERNELS'
list_kernels = Bool(config=True,
help="""Permits listing of the running kernels using API endpoints /api/kernels
and /api/sessions (KG_LIST_KERNELS env var). Note: Jupyter Notebook
allows this by default but kernel gateway does not."""
)
@default('list_kernels')
def list_kernels_default(self):
return os.getenv(self.list_kernels_env, 'False') == 'True'
api_env = 'KG_API'
api = Unicode('jupyter-websocket',
config=True,
help='Controls which API to expose, that of a Jupyter kernel or the seed notebook\'s, using values "jupyter-websocket" or "notebook-http" (KG_API env var)'
)
@default('api')
def api_default(self):
return os.getenv(self.api_env, 'jupyter-websocket')
def _api_changed(self, name, old, new):
if new not in ['notebook-http', 'jupyter-websocket']:
raise ValueError('Invalid API value, valid values are jupyter-websocket and notebook-http')
allow_notebook_download_env = 'KG_ALLOW_NOTEBOOK_DOWNLOAD'
allow_notebook_download = Bool(
config=True,
help="Optional API to download the notebook source code in notebook-http mode, defaults to not allow"
)
@default('allow_notebook_download')
def allow_notebook_download_default(self):
return os.getenv(self.allow_notebook_download_env, 'False') == 'True'
def _load_notebook(self, uri):
"""Loads a notebook from the local filesystem or HTTP URL.
Raises
------
RuntimeError if no installed kernel can handle the language specified
in the notebook.
Returns
-------
object
Notebook object from nbformat
"""
parts = urlparse(uri)
if parts.netloc == '' or parts.netloc == 'file':
# Local file
with open(parts.path) as nb_fh:
notebook = nbformat.read(nb_fh, 4)
else:
# Remote file
import requests
resp = requests.get(uri)
resp.raise_for_status()
notebook = nbformat.reads(resp.text, 4)
# Error if no kernel spec can handle the language requested
kernel_name = notebook['metadata']['kernelspec']['name']
self.kernel_spec_manager.get_kernel_spec(kernel_name)
return notebook
def initialize(self, argv=None):
"""Initializes the base class, configurable manager instances, the
Tornado web app, and the tornado HTTP server.
Parameters
----------
argv
Command line arguments
"""
super(KernelGatewayApp, self).initialize(argv)
self.init_configurables()
self.init_webapp()
self.init_http_server()
def init_configurables(self):
"""Initializes all configurable objects including a kernel manager, kernel
spec manager, session manager, kernel pool, and activity manager.
Optionally, loads a notebook and prespawns the configured number of
kernels.
"""
self.kernel_spec_manager = KernelSpecManager(parent=self)
self.seed_notebook = None
if self.seed_uri is not None:
# Note: must be set before instantiating a SeedingMappingKernelManager
self.seed_notebook = self._load_notebook(self.seed_uri)
# Only pass a default kernel name when one is provided. Otherwise,
# adopt whatever default the kernel manager wants to use.
kwargs = {}
if self.default_kernel_name:
kwargs['default_kernel_name'] = self.default_kernel_name
self.kernel_manager = SeedingMappingKernelManager(
parent=self,
log=self.log,
connection_dir=self.runtime_dir,
kernel_spec_manager=self.kernel_spec_manager,
**kwargs
)
self.activity_manager = ActivityManager(
parent=self,
log=self.log,
kernel_manager=self.kernel_manager
)
self.session_manager = SessionManager(
log=self.log,
kernel_manager=self.kernel_manager
)
self.contents_manager = None
if self.prespawn_count:
if self.max_kernels and self.prespawn_count > self.max_kernels:
raise RuntimeError('cannot prespawn {}; more than max kernels {}'.format(
self.prespawn_count, self.max_kernels)
)
if self.api == 'notebook-http':
self.kernel_pool = ManagedKernelPool(
self.prespawn_count,
self.kernel_manager
)
else:
self.kernel_pool = KernelPool(
self.prespawn_count,
self.kernel_manager
)
def init_webapp(self):
"""Initializes Tornado web application with kernel handlers.
Adds the various managers and web-front configuration values to the
Tornado settings for reference by the handlers.
Notes
-----
Uses the `api` setting to determine which handlers to add.
Developers should note: this may be refactored in the future.
"""
# Redefine handlers off the base_url path
handlers = []
if self.api == 'notebook-http':
# Register the NotebookDownloadHandler if configuration allows
if self.allow_notebook_download:
handlers.append((
url_path_join('/', self.base_url, r'/_api/source'),
NotebookDownloadHandler,
{'path': self.seed_uri}
))
# Discover the notebook endpoints and their implementations
parser = APICellParser(self.kernel_manager.seed_kernelspec)
endpoints = parser.endpoints(self.kernel_manager.seed_source)
response_sources = parser.endpoint_responses(self.kernel_manager.seed_source)
if len(endpoints) == 0:
raise RuntimeError('No endpoints were discovered. Check your notebook to make sure your cells are annotated correctly.')
# Cycle through the (endpoint_path, source) tuples and register their handlers
for endpoint_path, verb_source_map in endpoints:
parameterized_path = parameterize_path(endpoint_path)
parameterized_path = url_path_join('/', self.base_url, parameterized_path)
self.log.info('Registering endpoint_path: {}, methods: ({})'.format(
parameterized_path,
list(verb_source_map.keys())
))
response_source_map = response_sources[endpoint_path] if endpoint_path in response_sources else {}
handler_args = { 'sources' : verb_source_map,
'response_sources' : response_source_map,
'kernel_pool' : self.kernel_pool,
'kernel_name' : self.kernel_manager.seed_kernelspec
}
handlers.append((parameterized_path, NotebookAPIHandler, handler_args))
# Register the swagger API spec handler
handlers.append(
(url_path_join('/', self.base_url, r'/_api/spec/swagger.json'),
SwaggerSpecHandler, {
'notebook_path' : self.seed_uri,
'source_cells': self.kernel_manager.seed_source,
'kernel_spec' : self.kernel_manager.seed_kernelspec
}))
# Register the 404 catch-all last
handlers.append(default_base_handlers[-1])
# Enable the same pretty logging the notebook uses
enable_pretty_logging()
elif self.api == 'jupyter-websocket':
# append the activity monitor for websocket mode
handlers.append((
url_path_join('/', self.base_url, r'/_api/activity'),
ActivityHandler,
{}
))
# append tuples for the standard kernel gateway endpoints
for handler in (
default_api_handlers +
default_kernel_handlers +
default_kernelspec_handlers +
default_session_handlers +
default_base_handlers
):
# Create a new handler pattern rooted at the base_url
pattern = url_path_join('/', self.base_url, handler[0])
# Some handlers take args, so retain those in addition to the
# handler class ref
new_handler = tuple([pattern] + list(handler[1:]))
handlers.append(new_handler)
# Configure the tornado logging level too
logging.getLogger().setLevel(self.log_level)
self.web_app = web.Application(
handlers=handlers,
activity_manager=self.activity_manager,
kernel_manager=self.kernel_manager,
session_manager=self.session_manager,
contents_manager=self.contents_manager,
kernel_spec_manager=self.kernel_manager.kernel_spec_manager,
kg_auth_token=self.auth_token,
kg_allow_credentials=self.allow_credentials,
kg_allow_headers=self.allow_headers,
kg_allow_methods=self.allow_methods,
kg_allow_origin=self.allow_origin,
kg_expose_headers=self.expose_headers,
kg_max_age=self.max_age,
kg_max_kernels=self.max_kernels,
kg_list_kernels=self.list_kernels,
kg_api=self.api,
# Also set the allow_origin setting used by notebook so that the
# check_origin method used everywhere respects the value
allow_origin=self.allow_origin
)
def init_http_server(self):
"""Initializes a HTTP server for the Tornado web application on the
configured interface and port.
Tries to find an open port if the one configured is not available using
the same logic as the Jupyer Notebook server.
"""
self.http_server = httpserver.HTTPServer(self.web_app)
for port in random_ports(self.port, self.port_retries+1):
try:
self.http_server.listen(port, self.ip)
except socket.error as e:
if e.errno == errno.EADDRINUSE:
self.log.info('The port %i is already in use, trying another port.' % port)
continue
elif e.errno in (errno.EACCES, getattr(errno, 'WSAEACCES', errno.EACCES)):
self.log.warning("Permission to listen on port %i denied" % port)
continue
else:
raise
else:
self.port = port
break
else:
self.log.critical('ERROR: the notebook server could not be started because '
'no available port could be found.')
self.exit(1)
def start(self):
"""Starts an IO loop for the application."""
super(KernelGatewayApp, self).start()
self.log.info('The Jupyter Kernel Gateway is running at: http://{}:{}'.format(
self.ip, self.port
))
self.io_loop = ioloop.IOLoop.current()
try:
self.io_loop.start()
except KeyboardInterrupt:
self.log.info("Interrupted...")
finally:
self.shutdown()
def stop(self):
"""
Stops the HTTP server and IO loop associated with the application.
"""
def _stop():
self.http_server.stop()
self.io_loop.stop()
self.io_loop.add_callback(_stop)
def shutdown(self):
"""Stops all kernels in the pool."""
self.kernel_pool.shutdown()
launch_instance = KernelGatewayApp.launch_instance