Values of this type are objects. They contain these properties:

domainType Optional

A string. Specifies whether the network request is first-party or third-party to the domain from where it originated. If omitted, all requests are accepted. Possible values are "firstParty" and "thirdParty".

domains Deprecated Optional

An array of string. Use initiatorDomains instead. The rule only matches network requests originating from this list of domains.

excludedDomains Deprecated Optional

An array of string. Use excludedInitiatorDomains instead. The rule does not match network requests originating from this list of domains.

initiatorDomains Optional

An array of string. The rule only matches network requests originating from this list of domains. If the list is omitted, the rule is applied to requests from all domains. An empty list is not allowed. A canonical domain should be used. This matches against the request initiator and not the request URL.

excludedInitiatorDomains Optional

An array of string. The rule does not match network requests originating from this list of domains. If the list is empty or omitted, no domains are excluded. This takes precedence over initiatorDomains. A canonical domain should be used. This matches against the request initiator and not the request URL.

isUrlFilterCaseSensitive Optional

A boolean. Whether the urlFilter or regexFilter (whichever is specified) is case sensitive. Default is true in (older) versions of Chrome and Safari, and false in Firefox. There is consensus on defaulting to true across browsers in WECG issue 269.

regexFilter Optional

A string. Regular expression to match against the network request URL. Note that:

• The supported format is not stable and varies across browsers, see "Regular expressions in DNR API (regexFilter)" in WECG issue 344 for details.
• Only one of urlFilter or regexFilter can be specified.
• The regexFilter must be composed of only ASCII characters. This is matched against a URL where the host is encoded in the punycode format (in case of internationalized domains) and any other non-ascii characters are URL encoded in utf-8.

requestDomains Optional

An array of string. The rule only matches network requests when the domain matches one from this list. If the list is omitted, the rule is applied to requests from all domains. An empty list is not allowed. A canonical domain should be used.

excludedRequestDomains Optional

An array of string. The rule does not match network requests when the domains matches one from this list. If the list is empty or omitted, no domains are excluded. This takes precedence over requestDomains. A canonical domain should be used.

requestMethods Optional

An array of string. List of HTTP request methods that the rule matches. An empty list is not allowed. Specifying a requestMethods rule condition also excludes non-HTTP(s) requests, whereas specifying excludedRequestMethods does not.

excludedRequestMethods Optional

An array of string. List of request methods that the rule does not match on. Only one of requestMethods and excludedRequestMethods should be specified. If neither of them is specified, all request methods are matched.

resourceTypes Optional

An array of declarativeNetRequest.ResourceType. List of resource types that the rule matches with. An empty list is not allowed. This must be specified for "allowAllRequests" rules and may only include the "sub_frame" and "main_frame" resource types.

excludedResourceTypes Optional

An array of declarativeNetRequest.ResourceType. List of resource types that the rule does not match on. Only one of resourceTypes and excludedResourceTypes should be specified. If neither of them is specified, all resource types except "main_frame" are blocked.

tabIds Optional

An array of number. List of tabs.Tab.id that the rule should match. An ID of tabs.TAB_ID_NONE matches requests that don't originate from a tab. An empty list is not allowed. Only supported for session-scoped rules.

excludedTabIds Optional

An array of number. List of tabs.Tab.id that the rule should not match. An ID of tabs.TAB_ID_NONE excludes requests that do not originate from a tab. Only supported for session-scoped rules.

urlFilter Optional

A string. The pattern that is matched against the network request URL. Supported constructs:

• '*' : Wildcard: Matches any number of characters.
• '|' : Left or right anchor: If used at either end of the pattern, specifies the beginning or end of the URL respectively.
• '||' : Domain name anchor: If used at the beginning of the pattern, specifies the start of a (sub-)domain of the URL.
• '^' : Separator character: This matches anything except a letter, a digit. or one of _, -, ., or %. The last ^ may also match the end of the URL instead of a separator character. urlFilter is composed of the following parts: (optional left/domain name anchor) + pattern + (optional right anchor). If omitted, all URLs are matched. An empty string is not allowed. A pattern beginning with ||* is not allowed. Use * instead. Note that:
• Only one of urlFilter or regexFilter can be specified.
• The urlFilter must be composed of only ASCII characters. This is matched against a URL where the host is encoded in the punycode format (in case of internationalized domains) and any other non-ASCII characters are URL encoded in utf-8. For example, when the request URL is http://abc.рф?q=ф, the urlFilter is matched against the URL http://abc.xn--p1ai/?q=%D1%84.

Domains specified in initiatorDomains, excludedInitiatorDomains, requestDomains, or excludedRequestDomains should comply with the following:

• Sub-domains such as "a.example.com" are allowed.
• The entries must consist of only lowercase ASCII characters.
• Use Punycode encoding for internationalized domains.
• IPv4 addresses must be represented as 4 numbers separated by a dot.
• IPv6 addresses should be represented in their canonical form, wrapped in brackets.

To programmatically generate the canonical domain for a URL, use the URL API and read its hostname property, i.e., new URL(url).hostname.