Contents
The basic adapter sample illustrates the use of the TIBCO StreamBase® File Writer for Apache Hadoop Distributed File System (HDFS) by taking in a tuple and writing one of its fields contents to a file.
The advanced adapter sample illustrates reading from a sample input file multiple times and writing that data back out in various compression formats.
You must also open the FileWriterBasic.sbapp
or the FileWriterAdvanced.sbapp
file and select the Parameters tab and edit the value to represent both your current HDFS setup and where you would like to store the sample data. The .sbapp
files are located in → →
The SampleIn.txt
file used in the FileWriterAdvanced.sbapp
sample must be placed on your HDFS file system before this sample can run.
In StreamBase Studio, import this sample with the following steps:
-
From the top-level menu, select
→ . -
Type
hdfs
to narrow the list of options. -
Select hdfsfilewriter from the Large Data Storage and Analysis category.
-
Click
.
StreamBase Studio creates a single project containing the sample files.
-
In the Project Explorer, open the sample you just loaded.
-
Open the
src/main/eventflow
folder. -
Open the package folder (most samples contain a single package folder. Open the top-level package folder if your sample contains more than one folder).
-
Open the
FileWriterBasic.sbapp
application file and click the Run button. This opens the SB Test/Debug perspective and starts the application.If you see red marks, wait a moment for the project in Studio to load its features.
If red marks do not resolve themselves in a moment, select the project and right-click
→ from the context menu. -
In the Manual Output view, switch the
Stream
toData
, then enter a string value such as 'test', and then click to send a data tuple to be written to the file. Repeat for as many lines as you wish. -
In the Output Streams view, observe tuples emitted on the
Status
output streams indicating actions performed to the file. -
In the Manual Output view, switch the
Stream
toControl
, then enter 'Close' into theCommand
field, and then click to send a control tuple which will close the current file for writing. -
Press F9 or click the Stop Running Application button.
-
This demo will have now created a file in your project called
SampleOut.txt
containing the lines of data you submitted.
-
In the Project Explorer, open the sample you just loaded.
-
Open the
src/main/eventflow
folder. -
Open the package folder (most samples contain a single package folder. Open the top-level package folder if your sample contains more than one folder).
-
Open the
FileWriterAdvanced.sbapp
application file and click the Run button. This opens the SB Test/Debug perspective and starts the application.If you see red marks, wait a moment for the project in Studio to load its features.
If red marks do not resolve themselves in a moment, select the project and right-click
→ from the context menu. -
In the Output Streams view, observe tuples emitted on the
Status
output streams indicating actions performed to the files. -
Press F9 or click the Stop Running Application button.
-
This demo will have now created multiple files in your project:
-
Sample.gz
- This file is a GZip compressed file created from theSampleIn.txt
file. -
Sample.gz2
- This file is a BZip2 compressed file created from theSampleIn.txt
file. -
Sample.zip
- This file is a Zip compressed file created from theSampleIn.txt
file. -
SampleOut.txt
- This file is a un-compressed file created from theSampleIn.txt
file.
-
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_hdfsfilewriter
See Default Installation Directories for the default location of studio-workspace
on your system.