Description
A number of add-ons provide advanced features that require the use of regular expressions for pattern matching. Generally, just a simple understanding of regular expressions and a few examples are enough to get by for most use cases. This will just give a few simple examples to get started. Use the references for more advanced information.
Regex for workflow conditions
For JIRA workflow functions using regex expressions to condition whether the post function should continue processing, a blank pattern means that condition processing is not done and processing should continue.
Key tips
- Dot or period (.) is a special regex character. If you really want to match on it, you need to escape it with a backslash: \.
- Don't be confused with generic pattern matching used for file systems for instance. On a file system, *.png means all files ending with .png. That is an illegal regex expression. For regex you need: .*\.png. Or to simplify: .*png which will find all files ending in png (not necessarily ending in an extension of png).
- Regex is case sensitive by default. In most cases, use the case insensitive flag: (?i). See one of the examples below.
References
- Regex test site - test your expressions quickly
- Wikipedia regular expressions
- Regular expression reference
- Quick reference - best once you have the concepts
- Using word boundaries
Simple examples
Value | Regex | Matches | Demonstrates |
|---|---|---|---|
| ABC | A.C |  | . matches any single character |
| ABC | A.* | | * indicates 0 or more |
| ABC | .*C | | |
| A.B | A\.B | | Escape special regex characters with backslash if necessary |
| ABC | AB* |  | Regex is NOT generic matching |
| ABC | A.+ | | + indicates 1 or more |
| ABC | ABC.+ | | |
| ABC | ABC.* | | |
| ABCD | ABC.* | | |
| ABC | [ABCD] | | [ ] indicates a class of characters |
| ABC | [ABZ] | | |
| ABC8 | [A-Z0-9] | | - indicates a range of characters |
| ABC | [AB^C] | | ^ in a class means NOT the following character |
| ABC | DEF|ABC | | | indicates OR |
| image.png | .*png|.*jpg | | |
| image.jpg | .*png|.*jpg | | |
| image.JPG | .*png|.*jpg | | defaults to case sensitive matching |
| image.JPG | (?i).*png|.*jpg | | (?i) indicates case insensitive matching |
| ABAB | (AB)+ | | () indicates a grouping |
| ABCD | (AB)+ | | |
| 112233 | \d+ | | \d for digits |
| A B | A\s*B | | \s for whitespace |
| ABC | \S* | | \S for non whitespace |
| \S+ | | Value must have at least 1 non whitespace character | |
| A | \S+ | | |
| XYZ,ABC,UVW | .*\bABC\b.* | | Finding words in a comma or blank separated list using word boundaries |
| XYZ,ABCD,UVW | .*\bABC\b.* | |
Content with regex label
