Tag rules syntax¶

Tag rules follow the doublestar (aka globstar: **) matching pattern. Regex is unfortunately unsupported.

doublestar supports the following special terms in the patterns:

Special Terms	Meaning	Example pattern	Example matches	Example doesn't match	Reason
`*`	matches any sequence of characters (excludes /)	`env-*/app`	`env-prod/app` `env-dev/app`	`env-prod/sub/app`	Only matches the single directory level
`**`	matches any sequence of characters (includes /)	`**/redis`	`lib/redis` `proj/cache/redis`	`lib/redis-proxy`	Matches any path ending in exactly `/redis`
`?`	matches any single character (excludes /)	`qa-team?/*`	`qa-team0` `qa-team9`	`qa-team10/app`	Forces a single digit/letter suffix
`[class]`	matches any single character against a class of characters (See below) (excludes /)				see below
`{alt1,alt2,...}`	matches a sequence of characters if one of the comma-separated alternatives matches	`release-{beta,rc}`	`release-beta` `release-rc`	`release-alpha`	`alpha` is not an alternative

Any character with a special meaning can be escaped with a backslash (\).

Character classes support the following:

Class	Meaning	Example pattern	Example matches	Example doesn't match	Reason
`[abc]`	matches any single character within the set	`service-[ab]`	`service-a` `service-b`	`service-c`	`c` is not in Character class `[ab]`
`[a-z]` `[0-9]`	matches any single character in the range	`build-[0-9]`	`build-1` `build-7`	`build-a`	`a` not in range
`[^class]`	matches any single character which does not match the class	`release-[^9]*`	`release-1.0`	`release-9.0`	`9` is excluded from the class

Example for common tag pattern: Semantic Versioning (SemVer):

This is the most common versioning strategy (e.g., v1.0.1, 1.5.2).

This pattern uses alt-matches with an empty alt option, matching "nothing":

The pattern {v,} matches v or an empty string ("nothing") which means it can match strings which start with v or not.
The pattern [0-9]{,[0-9],[0-9][0-9]} matches a single digit (always) and one of 3 alt options: empty, single digit, or two digits; this gives us a matching pattern between 0 to 999
This limits us to to max version of v999.999.999 which should suffice for most usage. If not enough, just add another alt choice with more digits: [0-9]{,[0-9],[0-9][0-9],[0-9][0-9][0-9]}

Goal Pattern Matches Does Not Match

Strict 3-part SemVer with optional v prefix

{v,}[0-9]{,[0-9],[0-9][0-9]}.[0-9]{,[0-9],[0-9][0-9]}.[0-9]{,[0-9],[0-9][0-9]}

v1.5.9

7.10.3

1.250.22

v1
v1.0
latest