Match patterns
Match patterns are a way to specify groups of URLs: a match pattern matches a specific set of URLs. They are used in WebExtensions APIs in a few places, most notably to specify which documents to load content scripts into, and to specify which URLs to add webRequest
listeners to.
APIs that use match patterns usually accept a list of match patterns, and will perform the appropriate action if the URL matches any of the patterns. See, for example, the content_scripts
key in manifest.json.
Match pattern structure
Note: Some browsers don't support certain schemes. Check the Browser compatibility table for details.
All match patterns are specified as strings. Apart from the special
pattern, match patterns consist of three parts: scheme, host, and path. The scheme and host are separated by ://
.
://
scheme
The scheme component may take one of two forms:
Form | Matches |
---|---|
* |
Only "http" and "https" and in some browsers also "ws" and "wss". |
One of http , https , ws ,
wss , ftp , data ,
file , or (chrome-)extension .
|
Only the given scheme. |
host
The host component may take one of three forms:
Form | Matches |
---|---|
* |
Any host. |
*. followed by part of the hostname. |
The given host and any of its subdomains. |
A complete hostname, without wildcards. | Only the given host. |
host must not include a port number.
host is optional only if the scheme is "file".
Note that the wildcard may only appear at the start.
path
The path component must begin with a /
.
After that, it may subsequently contain any combination of the *
wildcard and any of the characters that are allowed in URL paths or query strings. Unlike host, the path component may contain the *
wildcard in the middle or at the end, and the *
wildcard may appear more than once.
The value for the path matches against the string which is the URL path plus the URL query string. This includes the ?
between the two, if the query string is present in the URL. For example, if you want to match URLs on any domain where the URL path ends with foo.bar
, then you need to use an array of Match Patterns like ["*://*/*foo.bar", "*://*/*foo.bar?*"]
. The ?*
is needed, rather than just bar*
, in order to anchor the ending *
as applying to the URL query string and not some portion of the URL path.
Neither the URL fragment identifier, nor the #
which precedes it, are considered as part of the path.
Note:
The path pattern string should not include a port number. Adding a port, as in: http://localhost:1234/*
causes the match pattern to be ignored. However, http://localhost:1234
will match with http://localhost/*
.
The special value
matches all URLs under any of the supported schemes: that is "http", "https", "ws", "wss", "ftp", "data", and "file".
Examples
Pattern | Example matches | Example non-matches |
---|---|---|
Match all URLs. |
|
|
Match all HTTP, HTTPS and WebSocket URLs. |
|
|
Match all HTTP, HTTPS and WebSocket URLs that are hosted at "mozilla.org" or one of its subdomains. |
|
|
Match all HTTP, HTTPS and WebSocket URLs that are hosted at exactly "mozilla.org/". |
|
|
Match only "ftp://mozilla.org/". |
ftp://mozilla.org |
|
Match HTTPS URLs on any host, whose path is "path". |
|
|
Match HTTPS URLs on any host, whose path is "path/" and which has no URL query string. |
|
|
Match HTTPS URLs only at "mozilla.org", with any URL path and URL query string. |
|
|
Match only this URL, or this URL with any URL fragment. |
|
Anything else. |
Match HTTPS URLs hosted on "mozilla.org", whose path contains a
component "b" somewhere in the middle. Will match URLs with query
strings, if the string ends in a |
|
|
Match any FILE URL whose path begins with "blah". |
|
file:///bleh/ (unmatched path) |
Invalid match patterns
Invalid pattern | Reason |
---|---|
resource://path/ |
Unsupported scheme. |
https://mozilla.org |
No path. |
https://mozilla.*.org/ |
"*" in host must be at the start. |
https://*zilla.org/ |
"*" in host must be the only character or be followed by ".". |
http*://mozilla.org/ |
"*" in scheme must be the only character. |
https://mozilla.org:80/ |
Host must not include a port number. |
*://* |
Empty path: this should be *://*/* . |
file://* |
Empty path: this should be file:///* . |