Source code for clustoapi.util

#!/usr/bin/env python
#
# -*- mode:python; sh-basic-offset:4; indent-tabs-mode:nil; coding:utf-8 -*-
# vim:set tabstop=4 softtabstop=4 expandtab shiftwidth=4 fileencoding=utf-8:
#

import bottle
import clusto
import json
import datetime


[docs]def get(name, driver=None): """ Tries to fetch a clusto object from a given name, optionally validating the driver given. Returns: * HTTP Error 404 if the object could not be found * HTTP Error 409 if the object does not match the expected driver * Clusto object otherwise """ status = None obj = None msg = None if driver and driver not in clusto.driverlist: status = 412 msg = u'The driver "%s" is not a valid driver' % (driver,) else: try: if driver: obj = clusto.get_by_name(name, assert_driver=clusto.driverlist[driver]) else: obj = clusto.get_by_name(name) except LookupError as le: status = 404 msg = u'Object "%s" not found (%s)' % (name, str(le),) except TypeError: status = 409 msg = u'The driver for object "%s" is not "%s"' % (name, driver,) return obj, status, msg
[docs]def dumps(obj, code=200, headers={}): """ Dumps a given object as a JSON string in an HTTP Response object. Will circumvent pretty-printing if Clusto-Minify header is True. """ # Merge global response headers into the response, but do not # let them override the current header values. for header, value in bottle.response.headers.items(): if headers.get(header) is None: headers[header] = value kwargs = {'sort_keys': True} headers['Clusto-Minify'] = bottle.request.headers.get('Clusto-Minify', default='False') if headers['Clusto-Minify'].lower() != 'true': kwargs['indent'] = 4 kwargs['separators'] = (',', ': ') return bottle.HTTPResponse( json.dumps(obj, **kwargs), code, content_type='application/json', **headers )
[docs]def unclusto(obj): """ Convert an object to a representation that can be safely serialized into JSON. """ if type(obj) in (str, unicode, int, list, dict) or obj is None: return obj if isinstance(obj, clusto.Attribute): return { 'key': obj.key, 'value': unclusto(obj.value), 'subkey': obj.subkey, 'number': obj.number, 'datatype': obj.datatype } if issubclass(obj.__class__, clusto.Driver): return '/%s/%s' % (obj.driver, obj.name) if isinstance(obj, datetime.datetime): return obj.isoformat() return str(obj)
[docs]def show(obj, mode=''): """ Will return the expanded or compact representation of a given object """ if not mode: mode = bottle.request.headers.get('Clusto-Mode', default='expanded') def compact(): return u'/%s/%s' % (obj.driver, obj.name) def expanded(): result = {} result['name'] = obj.name result['driver'] = obj.driver attrs = [] for x in obj.attrs(): attrs.append(unclusto(x)) result['attrs'] = attrs result['contents'] = [unclusto(x) for x in obj.contents()] result['parents'] = [unclusto(x) for x in obj.parents()] if isinstance(obj, clusto.drivers.resourcemanagers.ResourceManager): result['count'] = obj.count if 'get_ips' in dir(obj) and not obj.entity.type == 'ipmanager': result['ips'] = obj.get_ips() return result valid_modes = { 'compact': compact, 'expanded': expanded } if mode not in valid_modes: mode_error = '\'{0}\' is not a valid mode.'.format(mode) valid_mode_tip = 'Please choose from: {{{0}}}.'.format( ','.join(valid_modes.keys()) ) raise TypeError('{0} {1}'.format(mode_error, valid_mode_tip)) return valid_modes[mode]()
[docs]def page(ents, current=1, per=50): """ Takes a list of entities and drops all from a list but the current page. Returns a tuple that has the entities and also a page total so it may be returned to the client. """ first = (current - 1) * per last = current * per # 0:1 edge case with one entitiy. if not last: last = 1 total = len(ents) / per total = total + 1 if len(ents) % per else 0 return ents[first:last], total
[docs]def typecast(value, datatype, mask='%Y-%m-%dT%H:%M:%S.%f'): """ Takes a string and a valid clusto datatype and attempts to cast the value to the specified datatype. Will error out if a ValueError is incurred or a relation does not exist. Will aslo take a strptime format as ``mask`` because typcasting datetimes is hard. """ types = 'int', 'string', 'datetime', 'relation', 'json' if datatype not in types: bottle.abort(400, '%s is not a valid datatype. datatypes include: %s' % (datatype, str(types))) try: if datatype == 'int': return int(value) if datatype == 'string': return value if datatype == 'datetime': return datetime.datetime.strptime(value, mask) if datatype == 'relation': _, driver, name = value.split('/') obj, status, msg = get(name, driver=driver) if status > 299: bottle.abort(status, msg) return obj if datatype == 'json': return json.loads(value) except ValueError as ve: bottle.abort(400, 'Error casting %s into a(n) %s: %s' % (value, datatype, ve))