X-Git-Url: https://gerrit.onap.org/r/gitweb?a=blobdiff_plain;f=azure%2Faria%2Faria-extension-cloudify%2Fsrc%2Faria%2Faria%2Fparser%2Freading%2Freader.py;fp=azure%2Faria%2Faria-extension-cloudify%2Fsrc%2Faria%2Faria%2Fparser%2Freading%2Freader.py;h=1a29f11a5add34325e99d98b8d080602ff909e3e;hb=7409dfb144cf2a06210400134d822a1393462b1f;hp=0000000000000000000000000000000000000000;hpb=9e65649dfff8f00dc0a0ef6b10d020ae0e2255ba;p=multicloud%2Fazure.git diff --git a/azure/aria/aria-extension-cloudify/src/aria/aria/parser/reading/reader.py b/azure/aria/aria-extension-cloudify/src/aria/aria/parser/reading/reader.py new file mode 100644 index 0000000..1a29f11 --- /dev/null +++ b/azure/aria/aria-extension-cloudify/src/aria/aria/parser/reading/reader.py @@ -0,0 +1,44 @@ +# Licensed under the Apache License, Version 2.0 (the "License"); +# you may not use this file except in compliance with the License. +# You may obtain a copy of the License at +# +# http://www.apache.org/licenses/LICENSE-2.0 +# +# Unless required by applicable law or agreed to in writing, software +# distributed under the License is distributed on an "AS IS" BASIS, +# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +# See the License for the specific language governing permissions and +# limitations under the License. + +from ...utils.openclose import OpenClose +from .exceptions import ReaderException, AlreadyReadException + + +class Reader(object): + """ + Base class for ARIA readers. + + Readers provide agnostic raw data by consuming :class:`aria.parser.loading.Loader` instances. + """ + + def __init__(self, context, location, loader): + self.context = context + self.location = location + self.loader = loader + + def load(self): + with OpenClose(self.loader) as loader: + if self.context is not None: + with self.context._locations: + for location in self.context._locations: + if location.is_equivalent(loader.location): + raise AlreadyReadException('already read: %s' % loader.location) + self.context._locations.append(loader.location) + + data = loader.load() + if data is None: + raise ReaderException('loader did not provide data: %s' % loader) + return data + + def read(self): + raise NotImplementedError