How to use a PDI job to move a file into the MapR filesystem.
In order to follow along with this how-to guide you will need the following:
The sample data file needed for this guide is:
Start MapR if it is not already running.
Create a Job to Put the Files into MapR
In this task you will load a file into the MapR filesystem.
You can download the Kettle Job load_cldb.kjb if you don't want to do every step
- Start PDI on your desktop. Once it is running choose 'File' -> 'New' -> 'Job' from the menu system or click on the 'New file' icon on the toolbar and choose the 'Job' option.
- Add a Start Job Entry: You need to tell PDI where to start the job, so expand the 'General' section of the Design palette and drag a 'Start' job entry onto the job canvas.
- Add a Copy Files Job Entry: You will copy files from your local disk to the MapR filesystem, so expand the 'Big Data' section of the Design palette and drag a 'Hadoop Copy Files' job entry onto the job canvas. Your canvas should look like this:
- Connect the Start and Copy Files Job Entries: Hover the mouse over the 'Start' node and a tooltip will appear. Click on the output connector (the green arrow pointing to the right) and drag a connector arrow to the 'Hadoop Copy Files' node. Your canvas should look like this:
- Edit the Copy Files Job Entry: Double-click on the 'Hadoop Copy Files' node to edit its properties. Enter this information:
- File/Folder source(s): The folder containing the sample files you want to add to the MapR filesystem.
- File/Folder destination(s): maprfs://<CLDB>:<PORT>/weblogs/raw
When running PDI on the same machine as the MapR cluster use: maprfs:///weblogs/raw the MapR filesystem and port are not required.
<CLDB> is the server name of the machine running the MapR filesystem.
<PORT> is the port the MapR filesystem is running on.
- Wildcard (RegExp): Enter ^.*\.txt
- Click the Add button to add the above entries to the list of files you wish to copy.
- Check the "Create destination folder" option to ensure that the weblogs folder is created in the MapR filesystem the first time this job is executed.
When you are done your 'Copy Files' window should look like this (your file paths may be different):
Click 'OK' to close the window.
- Save the Job: Choose 'File' -> 'Save as...' from the menu system. Save the transformation as 'load_cldb.kjb' into a folder of your choice.
- Run the Job: Choose 'Action' -> 'Run' from the menu system or click on the green run button on the job toolbar. An 'Execute a job' window will open. Click on the 'Launch' button. An 'Execution Results' panel will open at the bottom of the PDI window and it will show you the progress of the job as it runs. After a few seconds the job should finish successfully:
If any errors occurred the job step that failed will be highlighted in red and you can use the 'Logging' tab to view error messages.
- If you have mounted your MapR filesystem onto your local machine you may verify the file loaded by navigating to the MapR directory.
This should return:
- If you have not mounted your MapR filesystem onto your local machine you may alternatively check MapR by:
This should return:
hadoop fs -ls /weblogs/raw
-rwxrwxrwx 3 demo demo 77908174 2011-12-28 07:16 /weblogs/raw/weblog_raw.txt
In this guide you learned how to copy local files into MapR's filesystem using PDI's graphical design tool. You can use this tool to put files into the MapR filesystem from many different sources.