gdapi.py

#!/usr/bin/env python
# PYTHON_ARGCOMPLETE_OK

import re
import requests
import collections
import hashlib
import os
import json
import time
try:
    import argcomplete
except ImportError:
    pass


def _prefix(cmd):
    prefix = os.path.basename(cmd.replace('-', '_'))
    for i in ['.pyc', '.py', '-cli', '-tool', '-util']:
        prefix = prefix.replace(i, '')
    return prefix.upper()

PREFIX = _prefix(__file__)
CACHE_DIR = '~/.' + PREFIX.lower()
TIME = not os.environ.get('TIME_API') is None

LIST = 'list-'
CREATE = 'create-'
UPDATE = 'update-'
DELETE = 'delete-'
ACTION = 'action-'
TRIM = True
JSON = False

GET_METHOD = 'GET'
POST_METHOD = 'POST'
PUT_METHOD = 'PUT'
DELETE_METHOD = 'DELETE'

HEADERS = {'Accept': 'application/json'}

LIST_METHODS = {'__iter__': True, '__len__': True, '__getitem__': True}


def echo(fn):
    def wrapped(*args, **kw):
        ret = fn(*args, **kw)
        print fn.__name__, repr(ret)
        return ret
    return wrapped


def timed_url(fn):
    def wrapped(*args, **kw):
        if TIME:
            start = time.time()
            ret = fn(*args, **kw)
            delta = time.time() - start
            print delta, args[1], fn.__name__
            return ret
        else:
            return fn(*args, **kw)
    return wrapped


class RestObject:
    def __init__(self):
        pass

    @staticmethod
    def _is_public(k, v):
        return k not in ['links', 'actions', 'id', 'type'] and not callable(v)

    def __str__(self):
        return self.__repr__()

    def _as_table(self):
        if not hasattr(self, 'type'):
            return str(self.__dict__)
        data = [('Type', 'Id', 'Name', 'Value')]
        for k, v in self.iteritems():
            if self._is_public(k, v):
                if v is None:
                    v = 'null'
                if v is True:
                    v = 'true'
                if v is False:
                    v = 'false'
                v = str(v)
                if TRIM and len(v) > 70:
                    v = v[0:70] + '...'
                data.append((self.type, self.id, str(k), v))

        return indent(data, hasHeader=True, prefix='| ', postfix=' |',
                      wrapfunc=lambda x: str(x))

    def _is_list(self):
        return 'data' in self.__dict__ and isinstance(self.data, list)

    def __repr__(self):
        data = {}
        for k, v in self.__dict__.iteritems():
            if self._is_public(k, v):
                data[k] = v
        return repr(data)

    def __getattr__(self, k):
        if self._is_list() and k in LIST_METHODS:
            return getattr(self.data, k)
        return getattr(self.__dict__, k)

    def __iter__(self):
        if self._is_list():
            return iter(self.data)


class Schema(object):
    def __init__(self, text, obj):
        self.text = text
        self.types = {}
        for t in obj:
            if t.type != 'schema':
                continue

            self.types[t.id] = t
            t.creatable = False
            try:
                if POST_METHOD in t.collectionMethods:
                    t.creatable = True
            except:
                pass

            t.updatable = False
            try:
                if PUT_METHOD in t.resourceMethods:
                    t.updatable = True
            except:
                pass

            t.deletable = False
            try:
                if DELETE_METHOD in t.resourceMethods:
                    t.deletable = True
            except:
                pass

            t.listable = False
            try:
                if GET_METHOD in t.collectionMethods:
                    t.listable = True
            except:
                pass

            if not hasattr(t, 'collectionFilters'):
                t.collectionFilters = {}

    def __str__(self):
        return str(self.text)

    def __repr(self):
        return repr(self.text)


class ApiError(Exception):
    def __init__(self, obj):
        self.error = obj
        try:
            msg = '{} : {}\n{}'.format(obj.code, obj.message, obj)
            super(ApiError, self).__init__(self, msg)
        except:
            super(ApiError, self).__init__(self, 'API Error')


class ClientApiError(Exception):
    pass


class Client(object):
    def __init__(self, access_key=None, secret_key=None, url=None, cache=False,
                 cache_time=86400, strict=False, headers=HEADERS, **kw):
        self._headers = headers
        self._access_key = access_key
        self._secret_key = secret_key
        self._auth = (self._access_key, self._secret_key)
        self._url = url
        self._cache = cache
        self._cache_time = cache_time
        self._strict = strict
        self.schema = None
        self._session = requests.Session()

        if not self._cache_time:
            self._cache_time = 60 * 60 * 24  # 24 Hours

        self._load_schemas()

    def valid(self):
        return self._url is not None and self.schema is not None

    def object_hook(self, obj):
        if isinstance(obj, list):
            return [self.object_hook(x) for x in obj]

        if isinstance(obj, dict):
            result = RestObject()

            for k, v in obj.iteritems():
                setattr(result, k, self.object_hook(v))

            for link in ['next', 'prev']:
                try:
                    url = getattr(result.pagination, link)
                    if url is not None:
                        setattr(result, link, lambda url=url: self._get(url))
                except AttributeError:
                    pass

            if hasattr(result, 'type') and isinstance(getattr(result, 'type'),
                                                      basestring):
                if hasattr(result, 'links'):
                    for link_name, link in result.links.iteritems():
                        cb = lambda _link=link, **kw: self._get(_link,
                                                                data=kw)
                        if hasattr(result, link_name):
                            setattr(result, link_name + '_link', cb)
                        else:
                            setattr(result, link_name, cb)

                if hasattr(result, 'actions'):
                    for link_name, link in result.actions.iteritems():
                        cb = lambda _link_name=link_name, _result=result, \
                            *args, **kw: self.action(_result, _link_name,
                                                     *args, **kw)
                        if hasattr(result, link_name):
                            setattr(result, link_name + '_action', cb)
                        else:
                            setattr(result, link_name, cb)

            return result

        return obj

    def object_pairs_hook(self, pairs):
        ret = collections.OrderedDict()
        for k, v in pairs:
            ret[k] = v
        return self.object_hook(ret)

    def _get(self, url, data=None):
        return self._unmarshall(self._get_raw(url, data=data))

    def _error(self, text):
        raise ApiError(self._unmarshall(text))

    @timed_url
    def _get_raw(self, url, data=None):
        r = self._get_response(url, data)
        return r.text

    def _get_response(self, url, data=None):
        r = self._session.get(url, auth=self._auth, params=data,
                              headers=self._headers)
        if r.status_code < 200 or r.status_code >= 300:
            self._error(r.text)

        return r

    @timed_url
    def _post(self, url, data=None):
        r = self._session.post(url, auth=self._auth, data=self._marshall(data),
                               headers=self._headers)
        if r.status_code < 200 or r.status_code >= 300:
            self._error(r.text)

        return self._unmarshall(r.text)

    @timed_url
    def _put(self, url, data=None):
        r = self._session.put(url, auth=self._auth, data=self._marshall(data),
                              headers=self._headers)
        if r.status_code < 200 or r.status_code >= 300:
            self._error(r.text)

        return self._unmarshall(r.text)

    @timed_url
    def _delete(self, url):
        r = self._session.delete(url, auth=self._auth, headers=self._headers)
        if r.status_code < 200 or r.status_code >= 300:
            self._error(r.text)

        return self._unmarshall(r.text)

    def _unmarshall(self, text):
        if text is None or text == '':
            return text
        obj = json.loads(text, object_hook=self.object_hook,
                         object_pairs_hook=self.object_pairs_hook)
        return obj

    def _marshall(self, obj, indent=None, sort_keys=False):
        if obj is None:
            return None
        return json.dumps(self._to_dict(obj), indent=indent, sort_keys=True)

    def _load_schemas(self, force=False):
        if self.schema and not force:
            return

        schema_text = self._get_cached_schema()

        if force or not schema_text:
            response = self._get_response(self._url)
            schema_url = response.headers.get('X-API-Schemas')
            if schema_url is not None and self._url != schema_url:
                schema_text = self._get_raw(schema_url)
            else:
                schema_text = response.text
            self._cache_schema(schema_text)

        obj = self._unmarshall(schema_text)

        schema = Schema(schema_text, obj)

        if len(schema.types) > 0:
            self._bind_methods(schema)
            self.schema = schema

    def reload_schema(self):
        self._load_schemas(force=True)

    def by_id(self, type, id, **kw):
        id = str(id)
        url = self.schema.types[type].links.collection
        if url.endswith('/'):
            url += id
        else:
            url = '/'.join([url, id])
        try:
            return self._get(url, self._to_dict(**kw))
        except ApiError, e:
            if e.error.status == 404:
                return None
            else:
                raise e

    def update_by_id(self, type, id, *args, **kw):
        url = self.schema.types[type].links.collection
        if url.endswith('/'):
            url = url + id
        else:
            url = '/'.join([url, id])

        return self._put(url, data=self._to_dict(*args, **kw))

    def update(self, obj, *args, **kw):
        url = obj.links.self
        return self._put(url, data=self._to_dict(*args, **kw))

    def _validate_list(self, type, **kw):
        if not self._strict:
            return

        collection_filters = self.schema.types[type].collectionFilters

        for k in kw:
            if hasattr(collection_filters, k):
                return

            for filter_name, filter_value in collection_filters.iteritems():
                for m in filter_value.modifiers:
                    if k == '_'.join([filter_name, m]):
                        return

            raise ClientApiError(k + ' is not searchable field')

    def list(self, type, **kw):
        if type not in self.schema.types:
            raise ClientApiError(type + ' is not a valid type')

        self._validate_list(type, **kw)
        collection_url = self.schema.types[type].links.collection
        return self._get(collection_url, data=self._to_dict(**kw))

    def reload(self, obj):
        return self.by_id(obj.type, obj.id)

    def create(self, type, *args, **kw):
        collection_url = self.schema.types[type].links.collection
        return self._post(collection_url, data=self._to_dict(*args, **kw))

    def delete(self, *args):
        for i in args:
            if isinstance(i, RestObject):
                return self._delete(i.links.self)

    def action(self, obj, action_name, *args, **kw):
        url = obj.actions[action_name]
        return self._post(url, data=self._to_dict(*args, **kw))

    def _is_list(self, obj):
        if isinstance(obj, list):
            return True

        if isinstance(obj, RestObject) and 'type' in obj.__dict__ and \
                obj.type == 'collection':
            return True

        return False

    def _to_value(self, value):
        if isinstance(value, dict):
            ret = {}
            for k, v in value.iteritems():
                ret[k] = self._to_value(v)
            return ret

        if isinstance(value, list):
            ret = []
            for v in value:
                ret.append(self._to_value(v))
            return ret

        if isinstance(value, RestObject):
            ret = {}
            for k, v in vars(value).iteritems():
                if not k.startswith('_') and \
                        not isinstance(v, RestObject) and not callable(v):
                    ret[k] = self._to_value(v)
                elif not k.startswith('_') and isinstance(v, RestObject):
                    ret[k] = self._to_dict(v)
            return ret

        return value

    def _to_dict(self, *args, **kw):
        if len(kw) == 0 and len(args) == 1 and self._is_list(args[0]):
            ret = []
            for i in args[0]:
                ret.append(self._to_dict(i))
            return ret

        ret = {}

        for i in args:
            value = self._to_value(i)
            if isinstance(value, dict):
                for k, v in value.iteritems():
                    ret[k] = v

        for k, v in kw.iteritems():
            ret[k] = self._to_value(v)

        return ret

    @staticmethod
    def _type_name_variants(name):
        ret = [name]
        python_name = re.sub(r'([a-z])([A-Z])', r'\1_\2', name)
        if python_name != name:
            ret.append(python_name.lower())

        return ret

    def _bind_methods(self, schema):
        bindings = [
            ('list', 'collectionMethods', GET_METHOD, self.list),
            ('by_id', 'collectionMethods', GET_METHOD, self.by_id),
            ('update_by_id', 'resourceMethods', PUT_METHOD, self.update_by_id),
            ('create', 'collectionMethods', POST_METHOD, self.create)
        ]

        for type_name, type in schema.types.iteritems():
            for name_variant in self._type_name_variants(type_name):
                for method_name, type_collection, test_method, m in bindings:
                    # double lambda for lexical binding hack, I'm sure there's
                    # a better way to do this
                    cb = lambda type_name=type_name, method=m: \
                        lambda *args, **kw: method(type_name, *args, **kw)
                    if hasattr(type, type_collection) and \
                            test_method in type[type_collection]:
                        setattr(self, '_'.join([method_name, name_variant]),
                                cb())

    def _get_schema_hash(self):
        h = hashlib.new('sha1')
        h.update(self._url)
        if self._access_key is not None:
            h.update(self._access_key)
        return h.hexdigest()

    def _get_cached_schema_file_name(self):
        if not self._cache:
            return None

        h = self._get_schema_hash()

        cachedir = os.path.expanduser(CACHE_DIR)
        if not cachedir:
            return None

        if not os.path.exists(cachedir):
            os.mkdir(cachedir)

        return os.path.join(cachedir, 'schema-' + h + '.json')

    def _cache_schema(self, text):
        cached_schema = self._get_cached_schema_file_name()

        if not cached_schema:
            return None

        with open(cached_schema, 'w') as f:
            f.write(text)

    def _get_cached_schema(self):
        if not self._cache:
            return None

        cached_schema = self._get_cached_schema_file_name()

        if not cached_schema:
            return None

        if os.path.exists(cached_schema):
            mod_time = os.path.getmtime(cached_schema)
            if time.time() - mod_time < self._cache_time:
                with open(cached_schema) as f:
                    data = f.read()
                return data

        return None


def _print_cli(client, obj):
    if obj is None:
        return

    if JSON:
        print client._marshall(obj, indent=2, sort_keys=True)
    elif callable(getattr(obj, '_as_table')):
        print obj._as_table()
    else:
        print obj

# {{{ http://code.activestate.com/recipes/267662/ (r7)
import cStringIO
import operator


def indent(rows, hasHeader=False, headerChar='-', delim=' | ', justify='left',
           separateRows=False, prefix='', postfix='', wrapfunc=lambda x: x):
        '''Indents a table by column.
             - rows: A sequence of sequences of items, one sequence per row.
             - hasHeader: True if the first row consists of the columns' names.
             - headerChar: Character to be used for the row separator line
                 (if hasHeader==True or separateRows==True).
             - delim: The column delimiter.
             - justify: Determines how are data justified in their column.
                 Valid values are 'left','right' and 'center'.
             - separateRows: True if rows are to be separated by a line
                 of 'headerChar's.
             - prefix: A string prepended to each printed row.
             - postfix: A string appended to each printed row.
             - wrapfunc: A function f(text) for wrapping text; each element in
                 the table is first wrapped by this function.'''
        # closure for breaking logical rows to physical, using wrapfunc
        def rowWrapper(row):
                newRows = [wrapfunc(item).split('\n') for item in row]
                return [[substr or '' for substr in item] for item in map(None, *newRows)]  # NOQA
        # break each logical row into one or more physical ones
        logicalRows = [rowWrapper(row) for row in rows]
        # columns of physical rows
        columns = map(None, *reduce(operator.add, logicalRows))
        # get the maximum of each column by the string length of its items
        maxWidths = [max([len(str(item)) for item in column])
                     for column in columns]
        rowSeparator = headerChar * (len(prefix) + len(postfix) +
                                     sum(maxWidths) +
                                     len(delim)*(len(maxWidths)-1))
        # select the appropriate justify method
        justify = {'center': str.center, 'right': str.rjust, 'left': str.ljust}[justify.lower()]  # NOQA
        output = cStringIO.StringIO()
        if separateRows:
            print >> output, rowSeparator
        for physicalRows in logicalRows:
            for row in physicalRows:
                print >> output, prefix \
                    + delim.join([justify(str(item), width) for (item, width) in zip(row, maxWidths)]) + postfix  # NOQA
            if separateRows or hasHeader:
                print >> output, rowSeparator
                hasHeader = False
        return output.getvalue()
# End {{{ http://code.activestate.com/recipes/267662/ (r7)


def _env_prefix(cmd):
    return _prefix(cmd) + '_'


def from_env(prefix=PREFIX + '_', factory=Client, **kw):
    args = dict((x, None) for x in ['access_key', 'secret_key', 'url', 'cache',
                                    'cache_time', 'strict'])
    args.update(kw)
    if not prefix.endswith('_'):
        prefix += '_'
    prefix = prefix.upper()
    return _from_env(prefix=prefix, factory=factory, **args)


def _from_env(prefix=PREFIX + '_', factory=Client, **kw):
    result = dict(kw)
    for k, v in kw.iteritems():
        if v is not None:
            result[k] = v
        else:
            result[k] = os.environ.get(prefix + k.upper())

        if result[k] is None:
            del result[k]

    if 'cache_time' in result:
        result['cache_time'] = int(result['cache_time'])

    if 'cache' in result:
        result['cache'] = result['cache'] is True or result['cache'] == 'true'
    return factory(**result)


def _general_args(help=True):
    import argparse

    parser = argparse.ArgumentParser(add_help=help)
    parser.add_argument('--access-key', dest='_access_key')
    parser.add_argument('--secret-key', dest='_secret_key')
    parser.add_argument('--url', dest='_url')
    parser.add_argument('--format', dest='_format', default='table',
                        choices=['table', 'json'])
    parser.add_argument('--cache', dest='_cache', action='store_true',
                        default=True)
    parser.add_argument('--no-cache', dest='_cache', action='store_false')
    parser.add_argument('--cache-time', dest='_cache_time', type=int)
    parser.add_argument('--strict', dest='_strict', type=bool)
    parser.add_argument('--trim', dest='_trim', action='store_true',
                        default=True)
    parser.add_argument('--no-trim', dest='_trim', action='store_false')

    return parser


def _list_args(subparsers, client, type, schema):
    help_msg = LIST[0:len(LIST)-1].capitalize() + ' ' + type
    subparser = subparsers.add_parser(LIST + type, help=help_msg)
    for name, filter in schema.collectionFilters.iteritems():
        subparser.add_argument('--' + name)
        for m in filter.modifiers:
            if m != 'eq':
                subparser.add_argument('--' + name + '_' + m)

    return subparser


def _map_load(value):
    value = value.strip()
    if len(value) == 0:
        return value

    if value[0] == '{':
        return json.loads(value)
    else:
        ret = {}
        for k, v in [x.strip().split('=', 1) for x in value.split(',')]:
            ret[k] = v
        return ret


def _generic_args(subparsers, field_key, type, schema,
                  operation=None, operation_name=None, help=None):
    if operation is None:
        prefix = operation_name
        help_msg = help
    else:
        prefix = operation + type
        help_msg_prefix = operation[0:len(operation)-1].capitalize()
        help_msg = help_msg_prefix + ' ' + type + ' resource'
    subparser = subparsers.add_parser(prefix, help=help_msg)

    if schema is not None:
        for name, field in schema.iteritems():
            if field.get(field_key) is True:
                if field.get('type').startswith('array'):
                    subparser.add_argument('--' + name, nargs='*')
                elif field.get('type').startswith('map'):
                    subparser.add_argument('--' + name, type=_map_load)
                else:
                    subparser.add_argument('--' + name)

    return subparser


def _full_args(client):
    parser = _general_args()
    subparsers = parser.add_subparsers(help='Sub-Command Help')
    for type, schema in client.schema.types.iteritems():
        if schema.listable:
            subparser = _list_args(subparsers, client, type, schema)
            subparser.set_defaults(_action=LIST, _type=type)
        if schema.creatable:
            subparser = _generic_args(subparsers, 'create', type,
                                      schema.resourceFields, operation=CREATE)
            subparser.set_defaults(_action=CREATE, _type=type)
        if schema.updatable:
            subparser = _generic_args(subparsers, 'update', type,
                                      schema.resourceFields, operation=UPDATE)
            subparser.add_argument('--id')
            subparser.set_defaults(_action=UPDATE, _type=type)
        if schema.deletable:
            subparser = _generic_args(subparsers, 'delete', type,
                                      {}, operation=DELETE)
            subparser.add_argument('--id')
            subparser.set_defaults(_action=DELETE, _type=type)

        try:
            for name, args in schema.resourceActions.iteritems():
                action_schema = None
                try:
                    action_schema = client.schema.types[args.input]
                except (KeyError, AttributeError):
                    pass
                help_msg = 'Action ' + name + ' on ' + type
                resource_fields = None
                if action_schema is not None:
                    resource_fields = action_schema.resourceFields
                subparser = _generic_args(subparsers, 'create', type,
                                          resource_fields,
                                          operation_name=type + '-' + name,
                                          help=help_msg)
                subparser.add_argument('--id')
                subparser.set_defaults(_action=ACTION + name, _type=type)

        except (KeyError, AttributeError):
            pass

    if 'argcomplete' in globals():
        argcomplete.autocomplete(parser)
    return parser


def _run_cli(client, namespace):
    args, command_type, type_name = _extract(namespace, '_action', '_type')
    args = _remove_none(args)

    try:
        if command_type == LIST:
            if 'id' in args:
                _print_cli(client, client.by_id(type_name, args['id']))
            else:
                result = client.list(type_name, **args)
                if JSON:
                    _print_cli(client, result)
                else:
                    for i in result:
                        _print_cli(client, i)

        if command_type == CREATE:
            _print_cli(client, client.create(type_name, **args))

        if command_type == DELETE:
            obj = client.by_id(type_name, args['id'])
            if obj is None:
                raise ClientApiError('{0} Not Found'.format(args['id']))
            client.delete(obj)
            _print_cli(client, obj)

        if command_type == UPDATE:
            _print_cli(client,
                       client.update_by_id(type_name, args['id'], args))

        if command_type.startswith(ACTION):
            obj = client.by_id(type_name, args['id'])
            if obj is None:
                raise ClientApiError('{0} Not Found'.format(args['id']))
            obj = client.action(obj, command_type[len(ACTION):], **args)
            if obj:
                _print_cli(client, obj)
    except ApiError, e:
        import sys

        sys.stderr.write('Error : {}\n'.format(e.error))
        status = int(e.error.status) - 400
        if status > 0 and status < 255:
            sys.exit(status)
        else:
            sys.exit(1)


def _remove_none(args):
    return dict(filter(lambda x: x[1] is not None, args.items()))


def _extract(namespace, *args):
    values = vars(namespace)
    result = [values]
    for arg in args:
        value = values.get(arg)
        result.append(value)
        try:
            del values[arg]
        except KeyError:
            pass

    return tuple(result)


def _get_generic_vars(argv):
    ret = []

    for arg in argv:
        if re.match(r'[a-zA-Z]+-[a-zA-Z]', arg):
            break
        ret.append(arg)

    return ret


def _cli_client(argv):
    generic_argv = _get_generic_vars(argv)
    args, unknown = _general_args(help=False).parse_known_args(generic_argv)

    global TRIM
    TRIM = args._trim

    global JSON
    if args._format == 'json':
        JSON = True

    dict_args = {}
    for k, v in vars(args).items():
        dict_args[k[1:]] = v

    prefix = _env_prefix(argv[0])
    return _from_env(prefix, **dict_args)


def _main():
    import sys
    client = _cli_client(sys.argv)
    if not client.valid():
        _general_args().print_help()
        sys.exit(2)

    args = _full_args(client).parse_args()
    _run_cli(client, args)

if __name__ == '__main__':
    _main()