Uploaded image for project: 'JBoss Enterprise Application Platform'
  1. JBoss Enterprise Application Platform
  2. JBEAP-20356

[GSS](7.3.z) WFLY-13976 - Undertow subsystem <filter-ref> does not resolve property expression for the predicate attribute

XMLWordPrintable

    • Icon: Bug Bug
    • Resolution: Done
    • Icon: Major Major
    • 7.3.4.CR1, 7.3.4.GA
    • 7.3.3.CR1
    • Undertow
    • None
    • False
    • False
    • +
    • Undefined
    • Workaround Exists
    • Hide

      Use <expresion-filter> and specify predicate inside the "expression" instead of using "predicate" of <filter-ref>. For example:

      <expression-filter name="dump-request-filter" expression="path-prefix('/${my.predicate.path.test}') -> dump-request"/>

      I think this workaround can be used in most cases. However, we can not use <expression-filter> in some cases. For example, the "request-limit" expression does not support all configurable parameters that the <request-limit> filter supports. (e.g. queue-size can not be specified to the "request-limit" expression.) So, we can not configure the exact same setting with <expression-filter>.

      Show
      Use <expresion-filter> and specify predicate inside the "expression" instead of using "predicate" of <filter-ref>. For example: <expression-filter name= "dump-request-filter" expression= "path-prefix( '/${my.predicate.path.test}' ) -> dump-request" /> I think this workaround can be used in most cases. However, we can not use <expression-filter> in some cases. For example, the "request-limit" expression does not support all configurable parameters that the <request-limit> filter supports. (e.g. queue-size can not be specified to the "request-limit" expression.) So, we can not configure the exact same setting with <expression-filter>.

      Undertow subsystem supports the property expression for the "predicate" attribute of <filter-ref> as shown below in the resource description. However, it does not resolve and expand the specified property expression.

      [standalone@node1:9990 /] /subsystem=undertow/server=default-server/host=default-host/filter-ref=*:read-resource-description(recursive=true)
{
    ...
        "result" => {
            "description" => "Reference to filter",
            "attributes" => {
                "predicate" => {
                    "type" => STRING,
                    "description" => "Predicates provide a simple way of making a true/false decision  based on an exchange. Many handlers have a requirement 
that they be applied conditionally, and predicates provide a general way to specify a condition.",
                    "expressions-allowed" => true,
                    "required" => false,
                    "nillable" => true,
                    "access-type" => "read-write",
                    "storage" => "configuration",
                    "restart-required" => "all-services"
                },
                "priority" => {
                    "type" => INT,
                    "description" => "Defines filter order. A lower number instructs the server to be included earlier in the handler chain than others with h
igher numbers. Values range from 1, indicating the filter will be handled first, to 2147483647, resulting in the filter being handled last.",
                    "expressions-allowed" => true,
                    "required" => false,
                    "nillable" => true,
                    "default" => 1,
                    "min" => 1L,
                    "max" => 2147483647L,
                    "access-type" => "read-write",
                    "storage" => "configuration",
                    "restart-required" => "all-services"
                }
            },
            "operations" => undefined,
            "notifications" => undefined,
            "children" => {}
        }
    }]
}

      Example configuration:

        <subsystem xmlns="urn:jboss:domain:undertow:10.0" ...>
      ...
      <server name="default-server">
          ...
          <host name="default-host" alias="localhost">
              ...
              <filter-ref name="request-limit-filter" predicate="not path-prefix('/${env.FOOBAR}')"/>
              <filter-ref name="dump-request-filter" predicate="path-prefix('/${my.predicate.path.test}')"/>
          </host>
      </server>
      ...
      <filters>
          <request-limit name="request-limit-filter" max-concurrent-requests="10" queue-size="1"/>
          <expression-filter name="dump-request-filter" expression="dump-request"/>
      </filters>
  </subsystem>

      Then, start EAP 7 with specifying the system property and environment variable:

      FOOBAR=example ./bin/standalone.sh -Dmy.predicate.path.test=test

              rhn-support-ivassile Ilia Vassilev
              rhn-support-mmiura Masafumi Miura
              Votes:
              0 Vote for this issue
              Watchers:
              8 Start watching this issue

                Created:
                Updated:
                Resolved: