HDFS File Writer and File System Adapter Sample

About This Sample

This sample illustrates the use of the Spotfire Streaming File System Adapter for Apache HDFS. The information provided in this guide walks you through the sample setup to run with your HDFS installation.

Initial Setup

To access the required files, open the Sample.sbapp file in the src/main/eventflow/packageName folder. Select the Parameters tab and edit the HDFS_FILE_PATH and HDFS_USER values to represent your HDFS setup.

Importing This Sample into StreamBase Studio

In StreamBase Studio, import this sample with the following steps:

  • From the top-level menu, select File>Import Samples and Community Content.

  • Enter hdfs to narrow the list of options.

  • Select HDFS File System adapter from the Large Data Storage and Analysis category.

  • Click Import Now.

StreamBase Studio creates a project for this sample.

Running This Sample in StreamBase Studio

  1. In the Project Explorer view, open the sample you just loaded.

    If you see red marks on a project folder, wait a moment for the project to load its features.

    If the red marks do not resolve themselves after a minute, select the project, right-click, and select Maven>Update Project from the context menu.

  2. Open the src/main/eventflow/packageName folder.

  3. Open the Sample.sbapp file and click the Run button. This opens the SB Test/Debug perspective and starts the module.

  4. In the Manual Input view, select OpenFile, and click Send Data to send the default tuple.

  5. In the Output Streams view, observe tuples emitted on the WriteStatus output stream with information about the file open action.

  6. In the Manual Input view, select CloseFile, click Send Data to send the default tuple.

  7. In the Output Streams view, observe tuples emitted on the WriteStatus output stream with information about the file close action.

  8. In the Manual Input view, select DeleteControl, click Send Data to send the default tuple.

  9. In the Output Streams view, observe tuples emitted on the DeleteStatus output stream with information about the file delete action.

  10. Press F9 or click the Terminate EventFlow Fragment button.

Sample Location

When you load the sample into StreamBase® Studio, Studio copies the sample project's files to your Studio workspace, which is normally part of your home directory, with full access rights.

Important

Load this sample in StreamBase® Studio, and thereafter use the Studio workspace copy of the sample to run and test it, even when running from the command prompt.

Using the workspace copy of the sample avoids permission problems. The default workspace location for this sample is:

studio-workspace/sample_adapter_embedded_hdfs

See Default Installation Directories for the default location of studio-workspace on your system.