sjwiesman commented on a change in pull request #13171: URL: https://github.com/apache/flink/pull/13171#discussion_r472338737
########## File path: docs/dev/table/python/debugging.md ########## @@ -0,0 +1,80 @@ +--- +title: "Debugging" +nav-parent_id: python_tableapi +nav-pos: 130 +--- +<!-- +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. +--> + +This page describes how to debug in PyFlink. + +* This will be replaced by the TOC +{:toc} + +## Logging Infos + +You can take use of Logging module of Python to print infos in Python UDF. e.g. + Review comment: ```suggestion Python UDFs can log contextual and debug information via standard Python logging modules. ``` ########## File path: docs/dev/table/python/debugging.md ########## @@ -0,0 +1,80 @@ +--- +title: "Debugging" +nav-parent_id: python_tableapi +nav-pos: 130 +--- +<!-- +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. +--> + +This page describes how to debug in PyFlink. + +* This will be replaced by the TOC +{:toc} + +## Logging Infos + +You can take use of Logging module of Python to print infos in Python UDF. e.g. + +{% highlight python %} + +@udf(input_types=[DataTypes.BIGINT(), DataTypes.BIGINT()], result_type=DataTypes.BIGINT()) +def add(i, j): + import logging + import sys + logging.basicConfig(stream=sys.stdout, level=logging.INFO, format="%(message)s") + logging.info("debug") + return i + j + +{% endhighlight %} + +## Watching Logs + +If you set the environment variable `FLINK_HOME`, logs will be placed in the log directory under `FLINK_HOME`. +Otherwise, logs will be placed in the directory of PyFlink module. You can execute following command to find +the log directory of PyFlink module: Review comment: ```suggestion If the environment variable `FLINK_HOME` is set, logs will be written in the log directory under `FLINK_HOME`. Otherwise, logs will be placed in the directory of the PyFlink module. You can execute the following command to find the log directory of PyFlink module: ``` ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: us...@infra.apache.org
