Portfolio Manager demo

A demonstration of a financial application where users can actively create and manage a portfolio of stocks.

The use case is a financial application where users can actively create and manage a portfolio of stocks. On the Cassandra OLTP (online transaction processing) side, each portfolio contains a list of stocks, the number of shares purchased, and the purchase price. The demo's pricer utility simulates real-time stock data where each portfolio updates based on its overall value and the percentage of gain or loss compared to the purchase price. This utility also generates 100 days of historical market data (the end-of-day price) for each stock. On the DSE OLAP (online analytical processing) side, a Hive MapReduce job calculates the greatest historical 10 day loss period for each portfolio, which is an indicator of the risk associated with a portfolio. This information is then fed back into the real-time application to allow customers to better gauge their potential losses.

Prerequisites

Before running the demo, make sure the following items have been completed:

A single-node or multiple node instance of DataStax Enterprise is installed.
The cluster is configured and running.

Procedure

To run the demo:

Check which mode DataStax Enterprise is running in:
- Packaged installs:
```
$ nodetool status
```
- Tarball installs:
```
$ bin/nodetool status
```
If the data center is not Analytics, stop the node:
- Packaged installs:
```
$ sudo service dse stop
```
- Tarball installs: From the install location:
```
$ install_location/bin/dse cassandra-stop  ## Use sudo if necessary
```
  In the unlikely event that the cassandra-stop command fails because it cannot find the process DataStax Enterprise Java process ID (PID), the output instructs you to find the DataStax Enterprise Java process ID (PID) manually, and stop the process using its PID number.
```
$ ps auwx | grep dse
$ bin/dse cassandra-stop -p PID
```
Start DataStax Enterprise as an analytics node:
- Packaged installs: Edit the /etc/default/dse file, and change
```
HADOOP_ENABLED=0
```
  to
```
HADOOP_ENABLED=1
```
  and then start DataStax Enterprise:
```
$ sudo service dse start
```
- Tarball installs:
```
$ install_location/bin/dse cassandra -t
```
Go to the portfolio manager demo directory:
1. Test whether the dse-demos directory exists.
```
$ file ~/dse-demos
```
2. If the directory does not exist:
```
$ install_dir/bin/make-dse-demos.sh
```
  The dse-demos directory is created in your current directory.
- GUI/Text Services and package installations: $ cd ~/dse-demos/portfolio_manager
- GUI/Text No Services and tarball installations: $ cd install_location/dse-demos/portfolio_manager
- Ran script to create directory $ cd dir-you-ran-script-in/dse-demos
Start the web service:
```
$ cd website
$ ./start
```
Open a browser and go to http://localhost:8983/portfolio.

The real-time Portfolio Manager demo application is displayed.
Open another terminal.
Start Hive and run the MapReduce job for the demo in Hive.
- GUI/Text Services and package installations: $ dse hive -f /usr/share/dse-demos/portfolio_manager/10_day_loss.q
- GUI/Text No Services and tarball installations: $ install_location/bin/dse hive -f install_location/demos/portfolio_manager/10_day_loss.q
The MapReduce job takes several minutes to run.
To watch the progress in the job tracker, open the following URL in a browser.

http://localhost:50030/jobtracker.jsp
After the job completes, refresh the Portfolio Manager web page.

The results of the Largest Historical 10 day Loss for each portfolio are displayed.