other_headers and other_headers_x match the HEADERS zone except Cookie, User-Agent Referer. Each list item is header_name:header_value both parts are Base64. At least one part must be set. Items in the list are combined with logical and.
The header name cannot contain !, &, or |. For other_headers, the logical operator ! on header_name follows the rule below. other_headers_x uses a regular expression in the value.
Base64 of header_name is aGVhZGVyX25hbWU=. An empty value matches any content of that header:
"other_headers": [
"aGVhZGVyX25hbWU=:"
]
Base64 of test-header is dGVzdC1oZWFkZXI=. Base64 of abc is YWJj. The rule matches only that header when its value contains abc:
"other_headers": [
"dGVzdC1oZWFkZXI=:YWJj"
]
Prefix the Base64 name with ! when the rule must not apply to that header. The rest of the list is still combined with &. Do not put ! inside the header name itself do not end the value with an operator. The combinations ||, &&, |& &| are not allowed. The same operator rules are in Request processing rules.