Chapter 34. DNS

DNS

Available as of Camel 2.7
This is an additional component for Camel to run DNS queries, using DNSJava. The component is a thin layer on top of DNSJava. The component offers the following operations:
ip
To resolve a domain by its IP address.
lookup
To look up information about the domain.
dig
To run DNS queries.
Requires SUN JVM
The DNSJava library requires running on the SUN JVM. If you use Apache ServiceMix or Apache Karaf, you'll need to adjust the etc/jre.properties file, to add sun.net.spi.nameservice to the list of Java platform packages exported. The server will need restarting before this change takes effect.
Maven users will need to add the following dependency to their pom.xml for this component: 
<dependency>
    <groupId>org.apache.camel</groupId>
    <artifactId>camel-dns</artifactId>
    <version>x.x.x</version>
    <!-- use the same version as your Camel core version -->
</dependency>

URI format

The URI scheme for a DNS component is as follows 
dns://operation
This component only supports producers.

Options

None.

Headers

Header Type Operations Description
dns.domain String ip The domain name. Mandatory.
dns.name String lookup The name to lookup. Mandatory.
dns.type - lookup, dig The type of the lookup. Should match the values of org.xbill.dns.Type. Optional.
dns.class - lookup, dig he DNS class of the lookup. Should match the values of org.xbill.dns.DClass. Optional.
dns.query String dig The query itself. Mandatory.
dns.server String dig The server in particular for the query. If none is given, the default one specified by the OS will be used. Optional.

Examples

IP lookup

        <route id="IPCheck">
            <from uri="direct:start"/>
            <to uri="dns:ip"/>
        </route>
This looks up a domain's IP. For example, www.example.com resolves to 192.0.32.10. The IP address to lookup must be provided in the header with key "dns.domain".

DNS lookup

        <route id="IPCheck">
            <from uri="direct:start"/>
            <to uri="dns:lookup"/>
        </route>
This returns a set of DNS records associated with a domain. The name to lookup must be provided in the header with key "dns.name".

DNS Dig

Dig is a Unix command-line utility to run DNS queries. 
        <route id="IPCheck">
            <from uri="direct:start"/>
            <to uri="dns:dig"/>
        </route>
The query must be provided in the header with key "dns.query".