Contents
This sample demonstrates the use of the Spotfire Streaming CSV File Reader Adapter for Apache Hadoop Distributed File System (HDFS).
The provided StreamBase module reads store sales data from CSV input files and computes total sales for storeID-productID
combinations. The HDFS CSV File Reader adapter instance named ReadFile1 reads from file1.csv, which contains sales data for storeA, while ReadFile2 reads from file2.csv containing sales data for storeX.
Both files contain records with missing productID values. ReadFile1 is configured to process such records, inserting null values for the unspecified productID fields. By contrast, ReadFile2 is configured to discard those records.
When you run the sample, look for output that shows the current total sales for each row read. Since ReadFile2 is configured to discard incomplete records, no output is emitted for storeX with null productID values.
The following files must be placed on your HDFS file system before the sample can run:
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file1.csv -
file2.csv
You must also open the csvreader-sample.sbapp file in the src/main/eventflow/ folder. Select the Parameters tab and edit the packageNameHDFS_FILE_PATH1, HDFS_FILE_PATH2, and HDFS_USER values to represent your HDFS setup to be able to access the required.
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
csvto narrow the list of options. -
Select HDFS CSV file 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
csvreader-sample.sbappfile and click the
Run button. This opens the SB Test/Debug perspective and starts the module.
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The two CSV reader adapters start reading from their input files and sending tuples downstream. Look for total sales computed values in the Output Streams view, and watch for line rejection warnings from
ReadFile2in the Console view. -
When done, 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_hdfscsvreaderSee Default Installation Directories for the default location of studio-workspace on your system.