Amar3tto opened a new pull request #17053: URL: https://github.com/apache/beam/pull/17053
Cdap package contains an io-connector for [CDAP](https://cdap.atlassian.net/wiki/home) sources and sinks. `CdapIO` is the primary class used in working with the connector in a pipeline. It contains static `PTransform` classes that represents reads/writes within the I/O (e.g. `Read`, `Write`).  `CdapIO.<~>read()` method method starts constructing a `CdapIO.Read` transform, it receives a type parameters`<~>` that specify the output type for CDAP source. The `Read` class implements an interface similar to the builder pattern and has simple `withX()` methods for passing configuration and other settings needed before start reading from CDAP source: - `withCdapPluginClass()` - pass a source/sink plugin class marked with CDAP `@Plugin` annotation. (e.g. `ZendeskBatchSource.class`) - `withPluginConfig()`- pass a corresponding `PluginConfig` object (e.g. `ZendeskBatchSourceConfig.class`) - `withKeyClass()` - specify the key class for the output (e.g. `NullWritable.class`) - `withValueClass()`- specify the value class for the output (e.g. `StructuredRecord.class`) Inside the `.withCdapPluginClass()` method, the `CdapPlugin` object is constructed. `CdapPlugin` object contains the following information about CDAP plugin: - Bounded/Unbounded - Input/Output - `BatchContextImpl` object for stubbing some CDAP-specific behavior - Format / Key / Value classes needed for filling Hadoop `Configuration` object - `T cdapPluginObj` for performing `prepareRun()` call before reading The following steps are performed in the `Read.expand()` method: - Validating that all configs and other obligatory fields are set - Call `CdapPlugin.prepareRun()` method before reading (see javadoc) - Construct the needed `Read` transform depending on whether the `CdapPlugin` is bounded / unbounded: - - For bounded sources `HadoopFormatIO.<K, V>read()` method is called passing filled Hadoop `Configuration` object. - - For unbounded sources `SparkReceiverIO.<~>read()` method is called.  ------------------------ Thank you for your contribution! Follow this checklist to help us incorporate your contribution quickly and easily: - [ ] [**Choose reviewer(s)**](https://beam.apache.org/contribute/#make-your-change) and mention them in a comment (`R: @username`). - [ ] Format the pull request title like `[BEAM-XXX] Fixes bug in ApproximateQuantiles`, where you replace `BEAM-XXX` with the appropriate JIRA issue, if applicable. This will automatically link the pull request to the issue. - [ ] Update `CHANGES.md` with noteworthy changes. - [ ] If this contribution is large, please file an Apache [Individual Contributor License Agreement](https://www.apache.org/licenses/icla.pdf). See the [Contributor Guide](https://beam.apache.org/contribute) for more tips on [how to make review process smoother](https://beam.apache.org/contribute/#make-reviewers-job-easier). To check the build health, please visit [https://github.com/apache/beam/blob/master/.test-infra/BUILD_STATUS.md](https://github.com/apache/beam/blob/master/.test-infra/BUILD_STATUS.md) GitHub Actions Tests Status (on master branch) ------------------------------------------------------------------------------------------------ [](https://github.com/apache/beam/actions?query=workflow%3A%22Build+python+source+distribution+and+wheels%22+branch%3Amaster+event%3Aschedule) [](https://github.com/apache/beam/actions?query=workflow%3A%22Python+Tests%22+branch%3Amaster+event%3Aschedule) [](https://github.com/apache/beam/actions?query=workflow%3A%22Java+Tests%22+branch%3Amaster+event%3Aschedule) See [CI.md](https://github.com/apache/beam/blob/master/CI.md) for more information about GitHub Actions CI. -- 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. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
