Sahara (Data Processing) UI User Guide
======================================

This guide assumes that you already have the Sahara service and Horizon
dashboard up and running. Don't forget to make sure that Sahara is registered in
Keystone. If you require assistance with that, please see the
`installation guide <../installation.guide.html>`_.

Launching a cluster via the Sahara UI
-------------------------------------
Registering an Image
--------------------

1) Navigate to the "Project" dashboard, then the "Data Processing" tab, then
   click on the "Image Registry" panel

2) From that page, click on the "Register Image" button at the top right

3) Choose the image that you'd like to register with Sahara

4) Enter the username of the cloud-init user on the image

5) Click on the tags that you want to add to the image. (A version ie: 1.2.1 and
   a type ie: vanilla are required for cluster functionality)

6) Click the "Done" button to finish the registration

Create Node Group Templates
---------------------------

1) Navigate to the "Project" dashboard, then the "Data Processing" tab, then
   click on the "Node Group Templates" panel

2) From that page, click on the "Create Template" button at the top right

3) Choose your desired Plugin name and Version from the dropdowns and click
   "Create"

4) Give your Node Group Template a name (description is optional)

5) Choose a flavor for this template (based on your CPU/memory/disk needs)

6) Choose the storage location for your instance, this can be either "Ephemeral
   Drive" or "Cinder Volume".  If you choose "Cinder Volume", you will need to add
   additional configuration

7) Choose which processes should be run for any instances that are spawned from
   this Node Group Template

8) Click on the "Create" button to finish creating your Node Group Template

Create a Cluster Template
-------------------------

1) Navigate to the "Project" dashboard, then the "Data Processing" tab, then
   click on the "Cluster Templates" panel

2) From that page, click on the "Create Template" button at the top right

3) Choose your desired Plugin name and Version from the dropdowns and click
   "Create"

4) Under the "Details" tab, you must give your template a name

5) Under the "Node Groups" tab, you should add one or more nodes that can be
   based on one or more templates

  - To do this, start by choosing a Node Group Template from the dropdown and
    click the "+" button
  - You can adjust the number of nodes to be spawned for this node group via
    the text box or the "-" and "+" buttons
  - Repeat these steps if you need nodes from additional node group templates

6) Optionally, you can adjust your configuration further by using the "General
   Parameters", "HDFS Parameters" and "MapReduce Parameters" tabs

7) Click on the "Create" button to finish creating your Cluster Template

Launching a Cluster
-------------------

1) Navigate to the "Project" dashboard, then the "Data Processing" tab, then
   click on the "Clusters" panel

2) Click on the "Launch Cluster" button at the top right

3) Choose your desired Plugin name and Version from the dropdowns and click
   "Create"

4) Give your cluster a name (required)

5) Choose which cluster template should be used for your cluster

6) Choose the image that should be used for your cluster (if you do not see any
   options here, see `Registering an Image`_ above)

7) Optionally choose a keypair that can be used to authenticate to your cluster
   instances

8) Click on the "Create" button to start your cluster

  - Your cluster's status will display on the Clusters table
  - It will likely take several minutes to reach the "Active" state

Scaling a Cluster
-----------------
1) From the Data Processing/Clusters page, click on the "Scale Cluster" button
   of the row that contains the cluster that you want to scale

2) You can adjust the numbers of instances for existing Node Group Templates

3) You can also add a new Node Group Template and choose a number of instances
   to launch

  - This can be done by selecting your desired Node Group Template from the
    dropdown and clicking the "+" button
  - Your new Node Group will appear below and you can adjust the number of
    instances via the text box or the "+" and "-" buttons

4) To confirm the scaling settings and trigger the spawning/deletion of
   instances, click on "Scale"

Elastic Data Processing (EDP)
-----------------------------
Data Sources
------------
Data Sources are where the input and output from your jobs are housed.

1) From the Data Processing/Data Sources page, click on the "Create Data Source"
   button at the top right

2) Give your Data Source a name

3) Enter the URL of the the Data Source

  - For a Swift object, enter <container>/<path> (ie: *mycontainer/inputfile*).
    Sahara will prepend *swift://* for you
  - For an HDFS object, enter an absolute path, a relative path or a full URL:

    + */my/absolute/path* indicates an absolute path in the cluster HDFS
    + *my/path* indicates the path */user/hadoop/my/path* in the cluster HDFS
      assuming the defined HDFS user is *hadoop*
    + *hdfs://host:port/path* can be used to indicate any HDFS location

4) Enter the username and password for the Data Source (also see
   `Additional Notes`_)

5) Enter an optional description

6) Click on "Create"

7) Repeat for additional Data Sources

Job Binaries
------------
Job Binaries are where you define/upload the source code (mains and libraries)
for your job.

1) From the Data Processing/Job Binaries page, click on the "Create Job Binary"
   button at the top right

2) Give your Job Binary a name (this can be different than the actual filename)

3) Choose the type of storage for your Job Binary

  - For "Swift", enter the URL of your binary (<container>/<path>) as well as
    the username and password (also see `Additional Notes`_)
  - For "Internal database", you can choose from "Create a script" or "Upload
    a new file"

4) Enter an optional description

5) Click on "Create"

6) Repeat for additional Job Binaries

Jobs
----
Jobs are where you define the type of job you'd like to run as well as which
"Job Binaries" are required

1) From the Data Processing/Jobs page, click on the "Create Job" button at the
   top right

2) Give your Job a name

3) Choose the type of job you'd like to run

4) Choose the main binary from the dropdown

   - This is required for Hive, Pig, and Spark jobs
   - Other job types do not use a main binary

5) Enter an optional description for your Job

6) Click on the "Libs" tab and choose any libraries needed by your job

   - MapReduce and Java jobs require at least one library
   - Other job types may optionally use libraries

7) Click on "Create"

Job Executions
--------------
Job Executions are what you get by "Launching" a job.  You can monitor the
status of your job to see when it has completed its run

1) From the Data Processing/Jobs page, find the row that contains the job you
   want to launch and click on the "Launch Job" button at the right side of that
   row

2) Choose the cluster (already running--see `Launching a Cluster`_ above) on
   which you would like the job to run

3) Choose the Input and Output Data Sources (Data Sources defined above)

4) If additional configuration is required, click on the "Configure" tab

  - Additional configuration properties can be defined by clicking on the "Add"
    button
  - An example configuration entry might be mapred.mapper.class for the Name and
    org.apache.oozie.example.SampleMapper for the Value

5) Click on "Launch".  To monitor the status of your job, you can navigate to
   the Sahara/Job Executions panel

6) You can relaunch a Job Execution from the Job Executions page by using the
   "Relaunch on New Cluster" or "Relaunch on Existing Cluster" links

  - Relaunch on New Cluster will take you through the forms to start a new
    cluster before letting you specify input/output Data Sources and job
    configuration
  - Relaunch on Existing Cluster will prompt you for input/output Data Sources
    as well as allow you to change job configuration before launching the job

Example Jobs
------------
There are sample jobs located in the sahara repository. In this section, we
will give a walkthrough on how to run those jobs via the Horizon UI. These steps
assume that you already have a cluster up and running (in the "Active" state).

1) Sample Pig job -
   https://github.com/openstack/sahara/tree/master/etc/edp-examples/pig-job

  - Load the input data file from
    https://github.com/openstack/sahara/tree/master/etc/edp-examples/pig-job/data/input
    into swift

    - Click on Projet/Object Store/Containers and create a container with any
      name ("samplecontainer" for our purposes here)

    - Click on Upload Object and give the object a name
      ("piginput" in this case)

  - Navigate to Data Processing/Data Sources, Click on Create Data Source

    - Name your Data Source ("pig-input-ds" in this sample)

    - Type = Swift, URL samplecontainer/piginput, fill-in the Source
      username/password fields with your username/password and click "Create"

  - Create another Data Source to use as output for the job

    - Name = pig-output-ds, Type = Swift, URL = samplecontainer/pigoutput,
      Source username/password, "Create"

  - Store your Job Binaries in the Sahara database

    - Navigate to Data Processing/Job Binaries, Click on Create Job Binary

    - Name = example.pig, Storage type = Internal database, click Browse and
      find example.pig wherever you checked out the sahara project
      <sahara root>/etc/edp-examples/pig-job

    - Create another Job Binary:  Name = udf.jar, Storage type = Internal
      database, click Browse and find udf.jar wherever you checked out the
      sahara project <sahara root>/etc/edp-examples/pig-job

  - Create a Job

    - Navigate to Data Processing/Jobs, Click on Create Job

    - Name = pigsample, Job Type = Pig, Choose "example.pig" as the main binary

    - Click on the "Libs" tab and choose "udf.jar", then hit the "Choose" button
      beneath the dropdown, then click on "Create"

  - Launch your job

    - To launch your job from the Jobs page, click on the down arrow at the far
      right of the screen and choose "Launch on Existing Cluster"

    - For the input, choose "pig-input-ds", for output choose "pig-output-ds".
      Also choose whichever cluster you'd like to run the job on

    - For this job, no additional configuration is necessary, so you can just
      click on "Launch"

    - You will be taken to the "Job Executions" page where you can see your job
      progress through "PENDING, RUNNING, SUCCEEDED" phases

    - When your job finishes with "SUCCEEDED", you can navigate back to Object
      Store/Containers and browse to the samplecontainer to see your output.
      It should be in the "pigoutput" folder

2) Sample Spark job -
   https://github.com/openstack/sahara/tree/master/etc/edp-examples/edp-spark

  - Store the Job Binary in the Sahara database

    - Navigate to Data Processing/Job Binaries, Click on Create Job Binary

    - Name = sparkexample.jar, Storage type = Internal database, Browse to the
      location <sahara root>/etc/edp-examples/edp-spark and choose
      spark-example.jar, Click "Create"

  - Create a Job

    - Name = sparkexamplejob, Job Type = Spark,
      Main binary = Choose sparkexample.jar, Click "Create"

  - Launch your job

    - To launch your job from the Jobs page, click on the down arrow at the far
      right of the screen and choose "Launch on Existing Cluster"

    - Choose whichever cluster you'd like to run the job on

    - Click on the "Configure" tab

    - Set the main class to be:  org.apache.spark.examples.SparkPi

    - Under Arguments, click Add and fill in the number of "Slices" you want to
      use for the job.  For this example, let's use 100 as the value

    - Click on Launch

    - You will be taken to the "Job Executions" page where you can see your job
      progress through "PENDING, RUNNING, SUCCEEDED" phases

    - When your job finishes with "SUCCEEDED", you can see your results by
      sshing to the Spark "master" node

    - The output is located at /tmp/spark-edp/<name of job>/<job execution id>.
      You can do ``cat stdout`` which should display something like
      "Pi is roughly 3.14156132"

    - It should be noted that for more complex jobs, the input/output may be
      elsewhere. This particular job just writes to stdout, which is logged in
      the folder under /tmp

Additional Notes
----------------
1) Throughout the Sahara UI, you will find that if you try to delete an object
   that you will not be able to delete it if another object depends on it.
   An example of this would be trying to delete a Job that has an existing Job
   Execution.  In order to be able to delete that job, you would first need to
   delete any Job Executions that relate to that job.

2) In the examples above, we mention adding your username/password for the Swift
   Data Sources. It should be noted that it is possible to configure Sahara such
   that the username/password credentials are *not* required. For more
   information on that, please refer to:
   :doc:`Sahara Advanced Configuration Guide <../userdoc/advanced.configuration.guide>`
