| #!/usr/bin/env python |
| """ |
| Licensed to the Apache Software Foundation (ASF) under one |
| or more contributor license agreements. See the NOTICE file |
| distributed with this work for additional information |
| regarding copyright ownership. The ASF licenses this file |
| to you 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. |
| |
| Ambari Agent |
| |
| """ |
| import re |
| |
| _MAX_SUBST = 20 |
| |
| def substitute_vars(raw, config): |
| """ |
| @param raw: str (e.g '${hbase.tmp.dir}/local') |
| @param config: dict (e.g {'hbase.tmp.dir': '/hadoop/hbase'}) |
| """ |
| result = raw |
| |
| pattern = re.compile("\$\{[^\}\$\x0020]+\}") |
| |
| for depth in range(0, _MAX_SUBST - 1): |
| match = pattern.search(result) |
| |
| if match: |
| start = match.start() |
| end = match.end() |
| |
| name = result[start + 2 : end - 1] |
| |
| try: |
| value = config[name] |
| except KeyError: |
| return result |
| |
| result = result[:start] + value + result[end:] |
| else: |
| break |
| |
| return result |