ironic can't find nodes whose name ends in ".<mimetype>"

[Andrew Balfour]

# Create a new node
% ironic node-create -d fake --name test.me
+--------------+--------------------------------------+
| Property | Value |
+--------------+--------------------------------------+
| chassis_uuid | |
| driver | fake |
| driver_info | {} |
| extra | {} |
| name | test.me |
| properties | {} |
| uuid | 78970da1-1621-4168-9062-e18bdcfc1836 |
+--------------+--------------------------------------+

# Display it
% ironic node-show test.me
Not Found (HTTP 404)

# Erm. It's there:
% ironic node-list | grep test.me
| 78970da1-1621-4168-9062-e18bdcfc1836 | test.me | None | None | available | False |

# And we can get it by uuid:
% ironic node-show 78970da1-1621-4168-9062-e18bdcfc1836 | grep name
| name | test.me

# It appears to be short circuiting somewhere before getting to ironic, as ironic returns a
# different 404:
% ironic node-show nosuchnode
Node nosuchnode could not be found. (HTTP 404)

Eventually we traverse far enough down the rabbit hole to pecan/core.py where in find_controller(), it tries to be helpful:

425 def find_controller(self, state):
426 '''
427 The main request handler for Pecan applications.
428 '''
[..]
445 # attempt to guess the content type based on the file extension
446 if self.guess_content_type_from_ext \
447 and not pecan_state['content_type'] \
448 and '.' in path:
449 _, extension = splitext(path.rstrip('/'))
450
451 # preface with a letter to ensure compat for 2.5
452 potential_type = guess_type('x' + extension)[0]
453
454 if extension and potential_type is not None:
455 path = ''.join(path.rsplit(extension, 1))
456 pecan_state['extension'] = extension
457 pecan_state['content_type'] = potential_type

(Pdb) p self.guess_content_type_from_ext
True
(Pdb) p pecan_state
{'routing_path': u'/v1/nodes/test.me', 'content_type': None}
(Pdb) p path
u'/v1/nodes/test.me'

So we fall in and hit 449, which sets extension to ".me", which is apparently the mime type for:

(Pdb) p potential_type
'application/x-troff-me'

So we fall into 454. This sets us up for failure at 510:

510 elif cfg.get('content_type') is not None and \
511 pecan_state['content_type'] not in content_types:
512
513 msg = "Controller '%s' defined does not support content_type " + \
514 "'%s'. Supported type(s): %s"
515 logger.error(
516 msg % (
517 controller.__name__,
518 pecan_state['content_type'],
519 content_types.keys()
520 )
521 )
522 -> raise exc.HTTPNotFound

because pecan is configured only to handle "application/json" requests:

(Pdb) p cfg['content_type']
'application/json'

and we've explicitly set the content type of this request to 'application/x-troff-me' it returns 404 at 522.

So, basically, if your nodename ends in ".<mimetype>", pecan won't let you see it because it never passes the request off to ironic:

% ironic node-update 78970da1-1621-4168-9062-e18bdcfc1836 replace name=test.mp3 > /dev/null
% ironic node-show test.mp3
Not Found (HTTP 404)
% ironic node-update 78970da1-1621-4168-9062-e18bdcfc1836 replace name=test.doc > /dev/null
% ironic node-show test.doc
Not Found (HTTP 404)
% ironic node-update 78970da1-1621-4168-9062-e18bdcfc1836 replace name=test.html > /dev/null
% ironic node-show test.html
Not Found (HTTP 404)
% ironic node-update 78970da1-1621-4168-9062-e18bdcfc1836 replace name=test.ok > /dev/null
% ironic node-show test.ok | grep name
| name | test.ok

A workaround would appear to be getting pecan's guess_content_type_from_ext option turned off by hacking it into both ironic/api/app.py and ironic/api/config.py?

E.g.

--- /usr/lib/python2.7/vendor-packages/ironic/api/config.py.orig 2016-06-21 12:57:28.000000000 -0700
+++ /usr/lib/python2.7/vendor-packages/ironic/api/config.py 2016-11-22 11:34:56.142128817 -0800
@@ -27,6 +27,7 @@
     'static_root': '%(confdir)s/public',
     'debug': False,
     'enable_acl': True,
+ 'guess_content_type_from_ext': False,
     'acl_public_routes': [
         '/',
         '/v1'
--- /usr/lib/python2.7/vendor-packages/ironic/api/app.py.orig 2016-06-21 12:57:24.000000000 -0700
+++ /usr/lib/python2.7/vendor-packages/ironic/api/app.py 2016-11-22 11:41:39.120103565 -0800
@@ -54,7 +54,6 @@
     filename = config.__file__.replace('.pyc', '.py')
     return pecan.configuration.conf_from_file(filename)

-
 def setup_app(pecan_config=None, extra_hooks=None):
     app_hooks = [hooks.ConfigHook(),
                  hooks.DBHook(),
@@ -78,6 +77,7 @@
         static_root=pecan_config.app.static_root,
         debug=CONF.pecan_debug,
         force_canonical=getattr(pecan_config.app, 'force_canonical', True),
+ guess_content_type_from_ext=getattr(pecan_config.app, 'guess_content_type_from_ext', True),
         hooks=app_hooks,
         wrap_app=middleware.ParsableErrorMiddleware,
     )

[Vladyslav Drok (vdrok)]

Thanks for reporting! The proposed fix should work. We can't microversion this change, so seems that we should set it to False by default, with some deprecation warning maybe? And after some time just always set guess_content_type_from_ext=True, as such possibility does not make much sense anyway - ironic supports only json content-type. Not really sure how to do that deprecation, apart from release note mention...

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/408597

[Kyrylo Romanenko (kromanenko)]

This bug also affects command `ironic node-delete`

[Kyrylo Romanenko (kromanenko)]

Named portgroups are also affected. I suppose that drivers too.

[Dmitry Tantsur (divius)]

Raising to high, as it seems to affect productions: https://bugzilla.redhat.com/show_bug.cgi?id=1536156

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/541289

[OpenStack Infra (hudson-openstack)]

Change abandoned by Dmitry Tantsur (<email address hidden>) on branch: master
Review: https://review.openstack.org/408597
Reason: I ended up with a complete change of the approach, see https://review.openstack.org/#/c/541289/

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/541289
Committed: https://git.openstack.org/cgit/openstack/ironic/commit/?id=cfc167eadfc373b262d92d8ce4a00a9fd38d23d7
Submitter: Zuul
Branch: master

commit cfc167eadfc373b262d92d8ce4a00a9fd38d23d7
Author: Dmitry Tantsur <email address hidden>
Date: Tue Feb 6 14:58:20 2018 +0100

    Stop guessing mime types based on URLs

    Currently we have a pecan feature enabled that strips extensions
    from the end of the URL and treat it like requested content type.
    E.g. /v1/nodes.json is treated as /v1/nodes with requested content
    type Application/Json. However, this prevents certain node names:
    e.g. /v1/nodes/small.1 is treated like /v1/nodes/small with content
    type of a man page. It does not make any sense for ironic API,
    as we only support Application/Json content type (and .json suffix).

    This change disabled this pecan feature. To keep backward compability
    a new middleware stips the .json prefix and saves a flag in the
    environment about its presence. API accepting names try to find
    their resource first without, then with .json suffix.

    The following endpoints are special-cased to support names with .json:
    * Node GET, PATCH and DELETE
    * Ramdisk heartbeat
    * Port group GET, PATCH and DELETE

    VIF API is not updated, so VIF IDs still cannot have .json suffix.

    Change-Id: I789ecfeac9b64a9c4105a20619f7bf5dfc133189
    Closes-Bug: #1643995

[OpenStack Infra (hudson-openstack)]

This issue was fixed in the openstack/ironic 10.1.0 release.