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JSR340 Filter in Worker

This tutorial will continue to introduce how to use JSR340 @WebFilter in zero system. Here are some points that should be mentioned because of some limitation between JSR340 and Vert.x:

  • All the filters must implement io.vertx.up.uca.web.filter.Filter instead of JSR340;
  • We recommend developers extend from io.vertx.up.uca.web.filter.HttpFilter directly because there are some abstract implementations in parent filters.
  • Please be careful of the signature of doFilter especially focus on the parameter types.

Demo projects:

  • Standalone - 6084: up-tethys

This tutorial will describe the usage of Filters in Consumer ( Worker ).

1. Source Code

1.1. Api

package up.god.micro.filter;

import io.vertx.core.json.JsonObject;
import io.vertx.up.annotations.Address;
import io.vertx.up.annotations.EndPoint;

import jakarta.ws.rs.BodyParam;
import javax.ws.rs.POST;
import javax.ws.rs.Path;

@EndPoint
@Path("/api")
public interface FilterApi {

    @POST
    @Path("/jsr340/worker")
    @Address("ZERO://JSR340/WORKER")
    JsonObject filter(@BodyParam final JsonObject data);
}

1.2. Consumer

package up.god.micro.filter;

import io.vertx.core.Future;
import io.vertx.core.json.JsonObject;
import io.vertx.up.annotations.Address;
import io.vertx.up.annotations.Queue;
import io.vertx.up.commune.Envelop;

@Queue
public class FilterWorker {

    @Address("ZERO://JSR340/WORKER")
    public Future<JsonObject> work(final Envelop envelop) {
        final String key = envelop.context("key", String.class);
        return Future.succeededFuture(new JsonObject().put("key", key));
    }
}

1.3. Filter

Here the code is the same as agent as following

package up.god.micro.filter;

import io.vertx.core.VertxException;
import io.vertx.core.http.HttpServerRequest;
import io.vertx.core.http.HttpServerResponse;
import io.vertx.up.uca.web.filter.HttpFilter;

import javax.servlet.annotation.WebFilter;
import java.io.IOException;

@WebFilter("/api/jsr340/*")
public class FirstFilter extends HttpFilter {

    @Override
    public void doFilter(final HttpServerRequest request,
                         final HttpServerResponse response)
            throws IOException, VertxException {
        System.out.println("First Filter");
        this.put("key", "First Filter");
    }
}

2. Testing

Then you can test this feature as following:

URL : http://localhost:6084/api/jsr340/worker

Method : POST

Response :

{
    "data": {
        "key": "First Filter"
    }
}

Here please be careful about the api of Envelop.context, you can extract the data from this api include any data type, the signature of this method is as following:

public <T> T context(final String key, final Class<T> clazz)

3. Summary

Based on current tutorial you can know how to use filters in Consumer ( Worker ) of zero system, and now you can set any code logical before your API.