Regular Expression Socket Reader Input Adapter Sample

Contents

Importing This Sample into StreamBase Studio
Sample Location
Running This Sample in StreamBase Studio
Running This Sample in Terminal Windows

This sample demonstrates a StreamBase application that processes a text log file, storing the information extracted from the log in a query table. The log file is typical of a server log: it contains information about user logins, as well as other, spurious information. The format of the log file means it is not particularly suited to direct use in an application. It does not, for example, consist of CSV records that are ready to be turned into tuples; it must be parsed first and useful information extracted. Because the log file is text and line oriented, it is well suited to parsing using regular expressions.

This example is based on the Regular Expression File Reader sample. The file reader in that application has been replaced by a socket reader, which is configured to connect to port 9000 on the local computer. The sample comes with a very simple server written in Java. The source code and compiled JAR of this server can be found in the sample's directory. The server simply listens on port 9000 and serves the contents of a file (by default, input.txt, though this can be specified on the command line) at one line per second to any connections.

Note

Before the sample application is started, the file server included in the sample directory must be running.

Importing This Sample into StreamBase Studio

In StreamBase Studio, import this sample with the following steps:

From the top menu, click File → Load StreamBase Sample.
Select this sample from the Embedded Adapters list.
Click OK.

StreamBase Studio creates a single project containing the sample files.

Sample Location

By default, the sample files are installed in:

On Windows: C:\Program Files\StreamBase Systems\StreamBase.n.m\sample\adapter\embedded\regexsocketreader\
On UNIX: /opt/streambase/sample/adapter/embedded/regexsocketreader/

When you load the sample into StreamBase Studio, Studio copies the sample project's files to your Studio workspace. StreamBase Systems recommends that you use the workspace copy of the sample, especially on UNIX, where you may not have write access to /opt/streambase. In the default installation, the path to this sample in your Studio workspace is:

UNIX:       
  ~/streambase-studio-n.m-workspace/sample_adapter_embedded_regexsocketreader
Windows XP:
  C:\Documents and Settings\username\My Documents\StreamBase Studio n.m Workspace\
      sample_adapter_embedded_regexsocketreader
Windows 7 and Windows Vista:
  C:\Users\username\Documents\StreamBase Studio n.m Workspace\
      sample_adapter_embedded_regexsocketreader

Running This Sample in StreamBase Studio

A simple Java server is provided as part of this sample. Run it as follows:
1. In the Package Explorer, open the Reference Libraries folder in this sample's project folder.
2. Select simpleserver.jar, right-click, and select Run As → Java Application. This opens a Console view that shows a message like the following:
```
Serving .\input.txt on port 9000 at one line per 1.0 seconds.
```
In the Package Explorer, double-click to open the RegexSocketReader.sbapp application. Make sure the application is the currently active tab in the EventFlow Editor.
Click the Run button. This opens the SB Test/Debug perspective and starts the application.
The Application Output view shows activity as the StreamBase application reads input from the Simple Server Java application.
Select the Manual Input tab.
Enter joe, fred, bob, or max for Username, and press Send Data.
The Application Output pane shows the time and IP address for the last queried user, according to the log.
When done, press F9 or click the Stop Running Application button to stop the StreamBase application.
In the Console view, use the Display Selected Console button to select the console showing SimpleServer.
Click the red square above the Console view to terminate the SimpleServer process.

Running This Sample in Terminal Windows

This section describes how to run the sample in UNIX terminal windows or Windows command prompt windows. On Windows, be sure to use the StreamBase Command Prompt from the Start menu as described in the Test/Debug Guide, not the default command prompt.

Open several terminal windows on UNIX, or several StreamBase Command Prompts on Windows. In each window, navigate to the directory where the sample is installed, or to your workspace copy of the sample, as described above.
Launch simpleserver.jar. To do from a terminal, run java -jar simpleserver.jar.
In another window, run sbd RegexSocketReader.sbapp
In another window, run sbc dequeue Output.
In another window, run sbc enqueue Queries.
In the enqueue window, type joe, fred, bob, or max, and press Enter. The result of your query appears in the dequeue window.
Run sbadmin shutdown.
In the window running simpleserver.jar, press Ctrl+C to stop the server.