Files
deb-python-dcos/dcos/api/marathon.py
José Armando García Sancio 8c7d16196b dcos-317 list versions for an app
2015-02-23 16:31:45 +00:00

373 lines
11 KiB
Python

import json
import requests
from dcos.api import errors, util
try:
from urllib import urlencode, quote
except ImportError:
from urllib.parse import urlencode, quote
logger = util.get_logger(__name__)
def create_client(config):
"""Creates a Marathon client with the supplied configuration.
:param config: configuration dictionary
:type config: config.Toml
:returns: Marathon client
:rtype: dcos.api.marathon.Client
"""
return Client(config['marathon.host'], config['marathon.port'])
class Client(object):
"""Class for talking to the Marathon server.
:param host: host for the Marathon server
:type host: str
:param port: port for the Marathon server
:type port: int
"""
def __init__(self, host, port):
self._url_pattern = "http://{host}:{port}/{path}"
self._host = host
self._port = port
def _create_url(self, path, query_params=None):
"""Creates the url from the provided path.
:param path: url path
:type path: str
:param query_params: query string parameters
:type query_params: dict
:returns: constructed url
:rtype: str
"""
url = self._url_pattern.format(
host=self._host,
port=self._port,
path=path)
if query_params is not None:
query_string = urlencode(query_params)
url = (url + '?{}').format(query_string)
return url
def _response_to_error(self, response):
"""
:param response: HTTP resonse object
:type response: requests.Response
:returns: the error embedded in the response JSON
:rtype: Error
"""
message = response.json().get('message')
if message is None:
errors = response.json().get('errors')
if errors is None:
logger.error(
'Marathon server did not return a message: %s',
response.json())
return Error('Unknown error from Marathon')
msg = '\n'.join(error['error'] for error in errors)
return Error('Error(s): {}'.format(msg))
return Error('Error: {}'.format(response.json()['message']))
def get_app(self, app_id, version=None):
"""Returns a representation of the requested application version. If
version is None the return the latest version.
:param app_id: the ID of the application
:type app_id: str
:param version: application version as a ISO8601 datetime
:type version: str
:returns: the requested Marathon application
:rtype: (dict, Error)
"""
app_id = normalize_app_id(app_id)
if version is None:
url = self._create_url('v2/apps{}'.format(app_id))
else:
url = self._create_url(
'v2/apps{}/versions/{}'.format(app_id, version))
logger.info('Getting %r', url)
response = requests.get(url)
logger.info('Got (%r): %r', response.status_code, response.json())
if _success(response.status_code):
# Looks like Marathon return different JSON for versions
if version is None:
return (response.json()['app'], None)
else:
return (response.json(), None)
else:
return (None, self._response_to_error(response))
def get_app_versions(self, app_id, max_count=None):
"""Asks Marathon for all the versions of the Application up to a
maximum count.
:param app_id: the ID of the application
:type app_id: str
:param max_count: the maximum number of version to fetch
:type max_count: int
:returns: a list of all the version of the application
:rtype: (list of str, Error)
"""
if max_count is not None and max_count <= 0:
return (
None,
Error(
'Maximum count must be a positive number: {}'.format(
max_count))
)
app_id = normalize_app_id(app_id)
url = self._create_url('v2/apps{}/versions'.format(app_id))
logger.info('Getting %r', url)
response = requests.get(url)
logger.info('Got (%r): %r', response.status_code, response.json())
if _success(response.status_code):
if max_count is None:
return (response.json()['versions'], None)
else:
return (response.json()['versions'][:max_count], None)
else:
return (None, self._response_to_error(response))
def get_apps(self):
"""Get a list of known applications.
:returns: list of known applications
:rtype: (list of dict, Error)
"""
url = self._create_url('v2/apps')
logger.info('Getting %r', url)
response = requests.get(url)
logger.info('Got (%r): %r', response.status_code, response.json())
if _success(response.status_code):
apps = response.json()['apps']
return (apps, None)
else:
return (None, self._response_to_error(response))
def add_app(self, app_resource):
"""Add a new application.
:param app_resource: application resource
:type app_resource: dict, bytes or file
:returns: the application description
:rtype: (dict, Error)
"""
url = self._create_url('v2/apps')
# The file type exists only in Python 2, preventing type(...) is file.
if hasattr(app_resource, 'read'):
app_json = json.load(app_resource)
else:
app_json = app_resource
logger.info('Posting %r to %r', app_json, url)
response = requests.post(url, json=app_json)
logger.info('Got (%r): %r', response.status_code, response.json())
if _success(response.status_code):
return (response.json(), None)
else:
return (None, self._response_to_error(response))
def update_app(self, app_id, payload, force=None):
"""Update an application.
:param app_id: the application id
:type app_id: str
:param payload: the json payload
:type payload: dict
:param force: whether to override running deployments
:type force: bool
:returns: the resulting deployment ID
:rtype: (str, Error)
"""
app_id = normalize_app_id(app_id)
if not force:
params = None
else:
params = {'force': 'true'}
url = self._create_url('v2/apps{}'.format(app_id), params)
logger.info('Putting %r to %r', payload, url)
response = requests.put(url, json=payload)
logger.info('Got (%r): %r', response.status_code, response.json())
if _success(response.status_code):
return (response.json().get('deploymentId'), None)
else:
return (None, self._response_to_error(response))
def scale_app(self, app_id, instances, force=None):
"""Scales an application to the requested number of instances.
:param app_id: the ID of the application to scale
:type app_id: str
:param instances: the requested number of instances
:type instances: int
:param force: whether to override running deployments
:type force: bool
:returns: the resulting deployment ID
:rtype: (bool, Error)
"""
app_id = normalize_app_id(app_id)
if not force:
params = None
else:
params = {'force': 'true'}
url = self._create_url('v2/apps{}'.format(app_id), params)
logger.info('Putting to %r', url)
response = requests.put(url, json={'instances': int(instances)})
logger.info('Got (%r): %r', response.status_code, response.json())
if _success(response.status_code):
deployment = response.json()['deploymentId']
return (deployment, None)
else:
return (None, self._response_to_error(response))
def stop_app(self, app_id, force=None):
"""Scales an application to zero instances.
:param app_id: the ID of the application to stop
:type app_id: str
:param force: whether to override running deployments
:type force: bool
:returns: the resulting deployment ID
:rtype: (bool, Error)
"""
return self.scale_app(app_id, 0, force)
def remove_app(self, app_id, force=None):
"""Completely removes the requested application.
:param app_id: the ID of the application to remove
:type app_id: str
:param force: whether to override running deployments
:type force: bool
:returns: Error if it failed to remove the app; None otherwise
:rtype: Error
"""
app_id = normalize_app_id(app_id)
if not force:
params = None
else:
params = {'force': 'true'}
url = self._create_url('v2/apps{}'.format(app_id), params)
logger.info('Deleting %r', url)
response = requests.delete(url)
logger.info('Got (%r)', response.status_code)
if _success(response.status_code):
return None
else:
return self._response_to_error(response)
def restart_app(self, app_id, force=None):
"""Performs a rolling restart of all of the tasks.
:param app_id: the id of the application to restart
:type app_id: str
:param force: whether to override running deployments
:type force: bool
:returns: the deployment id and version; Error otherwise
:rtype: (dict, Error)
"""
app_id = normalize_app_id(app_id)
if not force:
params = None
else:
params = {'force': 'true'}
url = self._create_url('v2/apps{}/restart'.format(app_id), params)
logger.info('Posting %r', url)
response = requests.post(url)
logger.info('Got (%r): %r', response.status_code, response.json())
if _success(response.status_code):
return (response.json(), None)
else:
return (None, self._response_to_error(response))
class Error(errors.Error):
""" Class for describing errors while talking to the Marathon server.
:param message: Error message
:type message: str
"""
def __init__(self, message):
self._message = message
def error(self):
"""Return error message
:returns: The error message
:rtype: str
"""
return self._message
def normalize_app_id(app_id):
"""Normalizes the application id.
:param app_id: raw application ID
:type app_id: str
:returns: normalized application ID
:rtype: str
"""
return quote('/' + app_id.strip('/'))
def _success(status_code):
"""Returns true if the success status is between [200, 300).
:param response_status: the http response status
:type response_status: int
:returns: True for success status; False otherwise
:rtype: bool
"""
return status_code >= 200 and status_code < 300