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author | 2018-01-11 14:53:14 -0500 | |
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committer | 2018-01-11 14:54:33 -0500 | |
commit | e91ad0d899121fb190391865422ea6424ffc29ca (patch) | |
tree | 33dc30947fff1dcec8b24a5506b36701ee0d4b08 /adapters/dcae/message_router.py | |
parent | d51c20ced007294d86e560f3bc9f5812cc17f193 (diff) |
Seed code for other adapters
Issue-ID: OPTFRA-47
Change-Id: I33595df23f077b2a9366c45b69afecdf80beaaf8
Signed-off-by: Sastry Isukapalli <sastry@research.att.com>
Diffstat (limited to 'adapters/dcae/message_router.py')
-rwxr-xr-x | adapters/dcae/message_router.py | 100 |
1 files changed, 100 insertions, 0 deletions
diff --git a/adapters/dcae/message_router.py b/adapters/dcae/message_router.py new file mode 100755 index 0000000..e495331 --- /dev/null +++ b/adapters/dcae/message_router.py @@ -0,0 +1,100 @@ +# ------------------------------------------------------------------------- +# Copyright (c) 2015-2017 AT&T Intellectual Property +# +# 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. +# +# ------------------------------------------------------------------------- +# + +import requests +from osdf.utils.data_types import list_like +from osdf.operation.exceptions import MessageBusConfigurationException + + +class MessageRouterClient(object): + def __init__(self, + dmaap_url=None, + mr_host_base_urls=None, + topic=None, + consumer_group=None, consumer_id=None, + timeout_ms=15000, fetch_limit=1000, + userid=None, passwd=None): + """ + :param dmaap_url: protocol, host and port; mostly for UEB + (e.g. https://dcae-msrt-ftl.homer.att.com:3905/) + :param mr_host_base_urls: for DMaaP, we get a topic URL (base_url + events/topic_name) + (e.g. https://dcae-msrt-ftl.homer.att.com:3905/events/com.att.dcae.dmaap.FTL.SNIRO-CM-SCHEDULER-RESPONSE) + :param consumer_group: DMaaP/UEB consumer group (unique for each subscriber; required for GET) + :param consumer_id: DMaaP/UEB consumer ID (unique for each thread/process for a subscriber; required for GET) + :param timeout_ms: (optional, default 15 seconds or 15,000 ms) server-side timeout for GET request + :param fetch_limit: (optional, default 1000 messages per request for GET), ignored for "POST" + :param userid: (optional, userid for HTTP basic authentication) + :param passwd: (optional, password for HTTP basic authentication) + """ + mr_error = MessageBusConfigurationException + if dmaap_url is None: # definitely not DMaaP, so use UEB mode + self.is_dmaap = False + if not (mr_host_base_urls and list_like(mr_host_base_urls)): + raise mr_error("Not a DMaaP or UEB configuration") + if not topic: + raise mr_error("Invalid topic: '{}'",format(topic)) + self.topic_urls = ["{}/events/{}".format(base_url, topic) for base_url in mr_host_base_urls] + else: + self.is_dmaap = True + self.topic_urls = [dmaap_url] + + self.timeout_ms = timeout_ms + self.fetch_limit = fetch_limit + self.auth = (userid, passwd) if userid and passwd else None + self.consumer_group = consumer_group + self.consumer_id = consumer_id + + def get(self, outputjson=True): + """Fetch messages from message router (DMaaP or UEB) + :param outputjson: (optional, specifies if response is expected to be in json format), ignored for "POST" + :return: response as a json object (if outputjson is True) or as a string + """ + url_fmt = "{topic_url}/{cgroup}/{cid}?timeout={timeout_ms}&limit={limit}" + urls = [url_fmt.format(topic_url=x, timeout_ms=self.timeout_ms, limit=self.fetch_limit, + cgroup=self.consumer_group, cid=self.consumer_id) for x in self.topic_urls] + for url in urls[:-1]: + try: + return self.http_request(method='GET', url=url, outputjson=outputjson) + except: + pass + return self.http_request(method='GET', url=urls[-1], outputjson=outputjson) + + def post(self, msg, inputjson=True): + for url in self.topic_urls[:-1]: + try: + return self.http_request(method='POST', url=url, inputjson=inputjson, msg=msg) + except: + pass + return self.http_request(method='POST', url=self.topic_urls[-1], inputjson=inputjson, msg=msg) + + def http_request(self, url, method, inputjson=True, outputjson=True, msg=None, **kwargs): + """ + Perform the actual URL request (GET or POST), and do error handling + :param url: full URL (including topic, limit, timeout, etc.) + :param method: GET or POST + :param inputjson: Specify whether input is in json format (valid only for POST) + :param outputjson: Is response expected in a json format + :param msg: content to be posted (valid only for POST) + :return: response as a json object (if outputjson or POST) or as a string; None if error + """ + res = requests.request(url=url, method=method, auth=self.auth, **kwargs) + if res.status_code == requests.codes.ok: + return res.json() if outputjson or method == "POST" else res.content + else: + raise Exception("HTTP Response Error: code {}; headers:{}, content: {}".format( + res.status_code, res.headers, res.content)) |