diff options
Diffstat (limited to 'policyhandler/pdp_api/policy_rest.py')
| -rw-r--r-- | policyhandler/pdp_api/policy_rest.py | 215 |
1 files changed, 215 insertions, 0 deletions
diff --git a/policyhandler/pdp_api/policy_rest.py b/policyhandler/pdp_api/policy_rest.py new file mode 100644 index 0000000..14d9296 --- /dev/null +++ b/policyhandler/pdp_api/policy_rest.py @@ -0,0 +1,215 @@ +# ================================================================================ +# Copyright (c) 2019 AT&T Intellectual Property. All rights reserved. +# ================================================================================ +# 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. +# ============LICENSE_END========================================================= +# + +"""policy-client communicates with policy-engine thru REST API""" + +import copy +import json +import os +import urllib.parse +from threading import Lock + +import requests + +from ..config import Config, Settings +from ..onap.audit import (REQUEST_X_ECOMP_REQUESTID, AuditHttpCode, + AuditResponseCode, Metrics) +from ..utils import Utils +from .pdp_consts import PDP_POLICIES +from .policy_utils import PolicyUtils + +_LOGGER = Utils.get_logger(__file__) + +class PolicyRest(object): + """using the http API to policy-engine""" + PDP_API_FOLDER = os.path.basename(os.path.dirname(os.path.realpath(__file__))) + _lazy_inited = False + DEFAULT_TIMEOUT_IN_SECS = 60 + + _lock = Lock() + _settings = Settings(Config.FIELD_POLICY_ENGINE, Config.POOL_CONNECTIONS) + + _target_entity = None + _requests_session = None + _url = None + _url_pdp_decision = None + _headers = None + _custom_kwargs = {} + _timeout_in_secs = DEFAULT_TIMEOUT_IN_SECS + + @staticmethod + def _init(): + """init static config""" + PolicyRest._custom_kwargs = {} + tls_ca_mode = None + + if not PolicyRest._requests_session: + PolicyRest._requests_session = requests.Session() + + changed, pool_size = PolicyRest._settings.get_by_key(Config.POOL_CONNECTIONS, 20) + if changed: + PolicyRest._requests_session.mount( + 'https://', requests.adapters.HTTPAdapter(pool_connections=pool_size, + pool_maxsize=pool_size)) + PolicyRest._requests_session.mount( + 'http://', requests.adapters.HTTPAdapter(pool_connections=pool_size, + pool_maxsize=pool_size)) + + _, config = PolicyRest._settings.get_by_key(Config.FIELD_POLICY_ENGINE) + if config: + PolicyRest._url = config.get("url") + if PolicyRest._url: + PolicyRest._url_pdp_decision = urllib.parse.urljoin( + PolicyRest._url, config.get("path_decision", "/decision/v1/")) + PolicyRest._headers = config.get("headers", {}) + PolicyRest._target_entity = config.get("target_entity", Config.FIELD_POLICY_ENGINE) + + tls_ca_mode = config.get(Config.TLS_CA_MODE) + PolicyRest._custom_kwargs = Config.get_requests_kwargs(tls_ca_mode) + PolicyRest._timeout_in_secs = config.get(Config.TIMEOUT_IN_SECS) + if not PolicyRest._timeout_in_secs or PolicyRest._timeout_in_secs < 1: + PolicyRest._timeout_in_secs = PolicyRest.DEFAULT_TIMEOUT_IN_SECS + + _LOGGER.info( + "PDP(%s) url(%s) headers(%s) tls_ca_mode(%s) timeout_in_secs(%s) custom_kwargs(%s): %s", + PolicyRest._target_entity, PolicyRest._url_pdp_decision, + Metrics.json_dumps(PolicyRest._headers), tls_ca_mode, + PolicyRest._timeout_in_secs, json.dumps(PolicyRest._custom_kwargs), + PolicyRest._settings) + + PolicyRest._settings.commit_change() + PolicyRest._lazy_inited = True + + @staticmethod + def reconfigure(): + """reconfigure""" + with PolicyRest._lock: + PolicyRest._settings.set_config(Config.discovered_config) + if not PolicyRest._settings.is_changed(): + PolicyRest._settings.commit_change() + return False + + PolicyRest._lazy_inited = False + PolicyRest._init() + return True + + @staticmethod + def _lazy_init(): + """init static config""" + if PolicyRest._lazy_inited: + return + + with PolicyRest._lock: + if PolicyRest._lazy_inited: + return + + PolicyRest._settings.set_config(Config.discovered_config) + PolicyRest._init() + + @staticmethod + def _pdp_get_decision(audit, pdp_req): + """Communication with the policy-engine""" + if not PolicyRest._url: + _LOGGER.error( + audit.error("no url for PDP", error_code=AuditResponseCode.AVAILABILITY_ERROR)) + audit.set_http_status_code(AuditHttpCode.SERVER_INTERNAL_ERROR.value) + return None + + with PolicyRest._lock: + session = PolicyRest._requests_session + target_entity = PolicyRest._target_entity + url = PolicyRest._url_pdp_decision + timeout_in_secs = PolicyRest._timeout_in_secs + headers = copy.deepcopy(PolicyRest._headers) + custom_kwargs = copy.deepcopy(PolicyRest._custom_kwargs) + + metrics = Metrics(aud_parent=audit, targetEntity=target_entity, targetServiceName=url) + + headers[REQUEST_X_ECOMP_REQUESTID] = metrics.request_id + + log_action = "post to {} at {}".format(target_entity, url) + log_data = "msg={} headers={}, custom_kwargs({}) timeout_in_secs({})".format( + json.dumps(pdp_req), Metrics.json_dumps(headers), json.dumps(custom_kwargs), + timeout_in_secs) + log_line = log_action + " " + log_data + + _LOGGER.info(metrics.metrics_start(log_line)) + + res = None + try: + res = session.post(url, json=pdp_req, headers=headers, timeout=timeout_in_secs, + **custom_kwargs) + except Exception as ex: + error_code = (AuditHttpCode.SERVICE_UNAVAILABLE_ERROR.value + if isinstance(ex, requests.exceptions.RequestException) + else AuditHttpCode.SERVER_INTERNAL_ERROR.value) + error_msg = ("failed {}: {} to {}".format(type(ex).__name__, str(ex), log_line)) + + _LOGGER.exception(error_msg) + metrics.set_http_status_code(error_code) + audit.set_http_status_code(error_code) + metrics.metrics(error_msg) + return None + + log_line = "response {} from {}: text={} headers={}".format( + res.status_code, log_line, res.text, + Metrics.json_dumps(dict(res.request.headers.items()))) + + _LOGGER.info(log_line) + metrics.set_http_status_code(res.status_code) + audit.set_http_status_code(res.status_code) + metrics.metrics(log_line) + + policy_bodies = None + if res.status_code == requests.codes.ok: + policy_bodies = res.json().get(PDP_POLICIES) + + return policy_bodies + + @staticmethod + def get_latest_policy(aud_policy_id): + """safely try retrieving the latest policy for the policy_id from the policy-engine""" + audit, policy_id, _, _ = aud_policy_id + try: + PolicyRest._lazy_init() + + pdp_req = PolicyUtils.gen_req_to_pdp(policy_id) + policy_bodies = PolicyRest._pdp_get_decision(audit, pdp_req) + + log_line = "looking for policy_id({}) in policy_bodies: {}".format( + policy_id, json.dumps(policy_bodies)) + _LOGGER.info(log_line) + + latest_policy = None + if policy_bodies and policy_id in policy_bodies: + latest_policy = PolicyUtils.convert_to_policy(policy_bodies[policy_id]) + + if not PolicyUtils.validate_policy(latest_policy): + audit.set_http_status_code(AuditHttpCode.DATA_NOT_FOUND_OK.value) + _LOGGER.error(audit.error( + "received invalid policy from PDP: {}".format(json.dumps(latest_policy)), + error_code=AuditResponseCode.DATA_ERROR)) + + return latest_policy + except Exception as ex: + error_msg = ("{}: get_latest_policy({}) crash {}: {}" + .format(audit.request_id, policy_id, type(ex).__name__, str(ex))) + + _LOGGER.exception(error_msg) + audit.fatal(error_msg, error_code=AuditResponseCode.BUSINESS_PROCESS_ERROR) + audit.set_http_status_code(AuditHttpCode.SERVER_INTERNAL_ERROR.value) + return None |