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C

Character encoding

Condition

Content

Context data

Cron

CSV

1 - Character encoding

Character Encoding is the means of encoding character data (i.e. text) into binary form. Therefore to decode character data from a stream of bytes, the character encoding must be known (or guessed).

Common examples of character encodings are ASCII, UTF-8 and UTF-16.

Each Feed has a defined character encoding for the data and context . This allows Stroom to decode the data sent into that Feed.

2 - Condition

A Condition in an query expression term, e.g. =, >, in, etc.

3 - Content

Content in Stroom typically means the user created documents/entities created in Stroom and as seen in the explorer tree. Content can be created/modified by Stroom users and imported/exported for sharing between different Stroom instances.

4 - Context data

This is an additional stream of contextual data that is sent along side the main event stream. It provides a means for the sending system to send additional data that relates only to the event stream it is sent alongside.

This can be useful where the sending system has no control over the data in the event stream and the event stream does not contain contextual information such as what machine it is running on or the location of that machine.

The contextual information (such as hostname, FQDN, physical location, etc.) can be sent in a Context Stream so that the two can be combined together during pipeline processing using stroom:lookup().

5 - Cron

Cron is a command line utility found on most linux/unix systems that is used for scheduling background tasks. Cron expressions (or variants of them) are widely used in other schedulers.

Stroom uses a scheduler called Quartz which supports cron expressions for scheduling. The full details of the cron syntax supported by Quartz can be found here .

6 - CSV

Comma Separated Values is a file format with typically one record per line and fields delimited by a ,. Fields may be optionally enclosed with double quotes, though there is no fixed standard for CSV data, particularly when it comes to escaping of double quotes and/or commas.