johnhpatton

server {

...

  location ~ ^/api/product/check_availability/.+ {
    # The key zone to use for cache lookups.
    # http://nginx.org/en/docs/http/ngx_http_proxy_module.html#proxy_cache
    proxy_cache                   availability;

    # http://nginx.org/en/docs/http/ngx_http_proxy_module.html#proxy_ignore_headers

johnhpatton

map $variable_to_check $variable_to_set {
    "check_if_variable_matches_me"   "variable_matches_checked_value";
    default                          "no_match";
}

johnhpatton

if [ "$variable_to_check" == "check_if_variable_matches_me" ]; then
    variable_to_set="variable_matches_checked_value"
else
    variable_to_set="no_match"
fi

johnhpatton

case $variable_to_check in:
    check_if_variable_matches_me)
        variable_to_set="variable_matches_checked_value"
        ;;
    *)
        variable_to_set="no_match"
        ;;
esac

johnhpatton

map $thing $useful_variable {
    "thing_matches_me"         "thing_matched_1";
    "nope_thing_matches_me"    "thing_matched_2";
    default                    "no_match";
}

johnhpatton

if ($thing1 = $thing2) {
   return 301 "{'Error': 'Things don't match!'}";
}

johnhpatton

# if delimeter between two variables is ':'
map $thing1:$thing2 $do_things_match {
    "~^([^:]+):\1$"         1;
    default                 0;
}

johnhpatton

map $request_uri $uri_only {
    "~^(?<u>[^\?]+)\?(?:.*)?"  $u;
    default                    $request_uri;
}

map $uri_only $shun_if_client_is_a_baddy {
    "~\/\/"                    1;
    "~*%2f"                    1;
    default                    0;
}

johnhpatton

if ($shun_if_client_is_a_baddy = 1) {
    return 403 'You shall not pass!!!';
}

johnhpatton

map $arg_FOO:$http_x_bar $shun_mismatched_payload {
    "~^([^:]+):\1$"         1;
    default                 0;
}