It should have picked it up, going through the gateway.sh file, I don't see
any place where ext folder is added to class path, can you open a BUG for
this ?
as a workaround for this you can copy your jar into the lib folder and Knox
should pick it up on the startup.
Hopefully, this should help !
Best,
Sandepe
On Fri, Mar 15, 2019 at 5:37 AM Matteo Alessandroni <skylar...@apache.org>
wrote:
> Hi Sandeep,
>
> thank you for your answer!
> Ok so I tried to change my project and adding a simple class like this:
>
> package com.test.ext;
>
> import java.io.IOException;
> import java.net.URI;
> import java.net.URISyntaxException;
> import javax.servlet.http.HttpServletRequest;
> import javax.servlet.http.HttpServletResponse;
> import org.apache.knox.gateway.config.Configure;
> import org.apache.knox.gateway.config.Default;
> import org.apache.knox.gateway.dispatch.AbstractGatewayDispatch;
> import org.slf4j.Logger;
> import org.slf4j.LoggerFactory;
>
> public class MyDispatch extends AbstractGatewayDispatch {
>
> private static final Logger LOG =
> LoggerFactory.getLogger(MyDispatch.class);
>
> @Override
> public void destroy() {
> LOG.debug("******* destroy()");
> }
>
> @Configure
> protected void customMethod(@Default("Test") String test) {
> LOG.debug("******* @Configure customMethod(): {}", test);
> }
>
> @Override
> public void doGet(URI url, HttpServletRequest request,
> HttpServletResponse response)
> throws IOException, URISyntaxException {
>
> LOG.debug("******* doGet() request: {}, {}", request.getMethod(),
> new URI(request.getRequestURI()));
>
> super.doGet(url, request, response);
> }
>
> }
>
> made the ".jar" and put in the "ext" folder.
> Executed the REST request again:
>
> curl -i -k -u admin:admin-password -X GET '
> https://localhost:8443/gateway/sandbox/webhdfs/v1/?op=LISTSTATUS'
>
> and I expected to see some logs, e.g. from the "doGet()" method (I'm not
> sure about the "@Configure" method, when should a method with that
> annotation be executed?), but it seems it does not see the class.
> So I tried to configure my topology to use the dispatch (as written on
> [1]):
>
> <service>
> <role>WEBHDFS</role>
> <url>http://hadoop-namenode:50070/webhdfs</url>
>
> <dispatch>
> <classname>com.test.ext.MyDispatch</classname>
> <use-two-way-ssl>false</use-two-way-ssl>
> </dispatch>
> </service>
>
> and after saving logs say:
>
> ERROR knox.gateway (GatewayFilter.java:doFilter(170)) - Gateway processing
> failed: javax.servlet.ServletException:
> org.apache.shiro.subject.ExecutionException:
> java.security.PrivilegedActionException: javax.servlet.ServletException:
> javax.servlet.ServletException: java.lang.ClassNotFoundException:
> com.test.ext.MyDispatch
> javax.servlet.ServletException:
> org.apache.shiro.subject.ExecutionException:
> java.security.PrivilegedActionException: javax.servlet.ServletException:
> javax.servlet.ServletException: *java.lang.ClassNotFoundException:
> com.test.ext.MyDispatch*
>
> so it's not seeing my class.
> What am I missing?
>
> Thank you!
>
> Matteo
>
>
> [1] https://knox.apache.org/books/knox-1-3-0/dev-guide.html#service.xml
>
>
> On 14/03/19 20:47, Sandeep Moré wrote:
>
> Hello Matteo,
>
> I don't think this is a right way to add filters to Knox, if you want to
> add some custom logic between your Knox and the backend you can write
> custom dispatch [1]
> you can add this new jar in the ext folder and it should be picked up by
> Knox on start-up.
>
> [1]
> https://knox.apache.org/books/knox-1-3-0/dev-guide.html#Custom+Dispatch+Dependency+Injection
>
>
> On Thu, Mar 14, 2019 at 12:52 PM Matteo Alessandroni <skylar...@apache.org>
> wrote:
>
>> Hi,
>>
>> I'm trying to add a filter on a Knox instance so that I'll be able to add
>> a custom logic to (every / specific) REST requests to Knox.
>> I thought to use the "Class Path" feature [1], so I created a Maven Java
>> project, generated a ".jar" file and placed it in the "$GATEWAY_HOME/ext"
>> folder
>> Then, I thought it was necessary to link my custom class [2] on the
>> "gateway.xml" files of the resources I wanted, e.g.
>>
>> ./data/deployments/sandbox.topo.16977ef2478/%2F/WEB-INF/gateway.xml
>>
>> added:
>>
>> <filter>
>> <role>rewrite</role>
>> <name>url-rewrite</name>
>> <class>com.test.knox.MyUrlRewriteServletFilter</class>
>> </filter>
>>
>> then I made a REST request to Knox:
>>
>> curl -i -k -u admin:admin-password -X GET '
>> https://localhost:8443/gateway/sandbox/webhdfs/v1/?op=LISTSTATUS'
>>
>> but my filter is not called at all (I cannot see the log) and I'm not
>> sure whether it's because the class is not loaded or the filter is placed
>> in the wrong place or whatever.
>>
>> On [4] you can see the project I have built.
>>
>> So my questions are:
>>
>> - what am I doing wrong or missing?
>> - is there a better way to do that? I just need to add a logic when
>> executing REST requests to Knox and make another REST call to an external
>> service I need.
>>
>>
>> Thank you!
>> Regards,
>> Matteo
>>
>> [1] https://knox.apache.org/books/knox-1-2-0/dev-guide.html#Class+Path
>> [2]
>> https://github.com/mat-ale/apache-knox-filter/blob/master/src/main/java/com/plainid/ext/MyUrlRewriteServletFilter.java
>> [3]
>> [4] https://github.com/mat-ale/apache-knox-filter
>>
>>
>>
>
