Contents
This adapter sample illustrates the use of the Spotfire Streaming Text File Reader Adapter for Apache Hadoop Distributed File System (HDFS) by reading a file and emitting a tuple that contains the file's contents in a string field.
The MyFile.txt file used in this sample must be placed
on your HDFS file system before this sample can run.
You must also open the filereader.sbapp file in the
src/main/eventflow/ folder. Select the Parameters tab and edit the packageNameHDFS_FILE_PATH and HDFS_USER values to
represent your HDFS setup, as well as to be able to access the required files.
In StreamBase Studio, import this sample with the following steps:
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From the top-level menu, select >.
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Enter
hdfsto narrow the list of options. -
Select HDFS File reader input adapter from the Large Data Storage and Analysis category.
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Click .
StreamBase Studio creates a project for this sample.
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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 > from the context menu.
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Open the
src/main/eventflow/folder.packageName -
Open the
filereader.sbappfile and click the
Run button. This opens the SB
Test/Debug perspective and starts the module.
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In the Manual Input view, click to send the default
nulltuple. -
In the Output Streams view, observe tuples emitted on the
StatusandDataoutput streams, the latter of which contains the contents of the configured default file,MyFile.txt. -
Press F9 or click the
Terminate EventFlow Fragment button.
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_hdfsfilereader
See Default Installation
Directories for the default location of studio-workspace on your system.