Custom ConnectorConfigurator not being detected

Camunda 7 Topics Discussion & Questions
1

Hi,

I am using a pre-built distribution of Camunda BPM 7.7.0 on Windows 10 and I am having trouble getting a ConnectorConfigurator for the HTTPConnector working.

The goal of my ConnectorConfigurator is to alter the headers for requests sent by the HTTPConnector so that the ‘Authorization’ attribute is controlled via server configuration. The ConnectorConfigurator registers a ConnectorRequestInterceptor which, on invocation, modifies the headers of the request but I am unable to get the ConnectorConfigurator to be detected/registered with the Camunda Engine. Nothing appears in the logs about the loading of the ConnectorConfigurator and the authentication header is not set.

I believe that the part that is causing the issue is this part in the documentation:

Add the configurator’s fully qualified classname to a file named
‘META-INF/services/org.camunda.connect.spi.ConnectorConfigurator’

There are multiple META-INF folders located in the pre-built distribution but I imagine it belongs in the camunda webapp folder: camunda-bpm-tomcat-7.7.0\server\apache-tomcat-8.0.24\webapps\camunda

This directory contains two META-INF folders: \META-INF\services and \WEB-INF\classes\META-INF\services

I have created org.camunda.connect.spi.ConnectorConfigurator in both META-INF containing the following line: org.awesome.camunda.ConnectorConfiguration.HttpConnectorConfigurator

I am building the jar file using IntelliJ IDEA and in the Kotlin language. I have a working Camunda engine plugin written in Kotlin which works wonders to perform REST webservice calls using Retrofit upon certain tasks being started so i am ruling out Kotlin as being an issue. The jar file is being deployed to: camunda-bpm-tomcat-7.7.0\server\apache-tomcat-8.0.24\lib

If anyone could provide any assistance or examples of a working ConnectorConfigurator using a pre-built re-built distribution of Camunda BPM 7.7.0 that would be fantastic. There doesn’t appear to be any similar issues in the forums or the old google groups section.

Code:

package org.awesome.camunda.ConnectorConfiguration

import org.camunda.connect.httpclient.HttpConnector
import org.camunda.connect.httpclient.impl.AbstractHttpRequest
import org.camunda.connect.httpclient.impl.HttpRequestImpl
import org.camunda.connect.httpclient.impl.HttpRequestInvocation
import org.camunda.connect.spi.ConnectorConfigurator
import org.camunda.connect.spi.ConnectorInvocation
import org.camunda.connect.spi.ConnectorRequestInterceptor
import java.util.logging.Logger

class HttpConnectorConfigurator : ConnectorConfigurator<HttpConnector>
{
    private final var LOGGER: Logger = Logger.getLogger(this.javaClass.name);

    override fun configure(httpConnector: HttpConnector) {
        LOGGER.info("HttpConnectorConfigurator - configure");
        httpConnector.addRequestInterceptor(HttpConnectorRequestInterceptor());
    }

    override fun getConnectorClass(): Class<HttpConnector> {
        LOGGER.info("HttpConnectorConfigurator - getConnectorClass");
        return HttpConnector::class.java
    }
}

class HttpConnectorRequestInterceptor : ConnectorRequestInterceptor
{
    private final var LOGGER: Logger = Logger.getLogger(this.javaClass.name);

    override fun handleInvocation(connectorInvocation: ConnectorInvocation): Any {
        LOGGER.info("HttpConnectorRequestInterceptor - handleInvocation");

        if(connectorInvocation is HttpRequestInvocation)
        {
            val request = connectorInvocation.target;
            if(request is HttpRequestBase)
            {
                request.addHeader("Authorization", "test");
            }
        }

        return connectorInvocation.proceed()
    }
}
2

Hi @Zek99,

The file should be part of the jar file that contains the connector.

Here is an example project for a Camunda Spin configurator: https://github.com/camunda/camunda-bpm-examples/tree/master/spin/dataformat-configuration-global. Configuring Spin works in the same way as configuring Connect. You can build it by running mvn clean install and the take a look at the resulting jar file.

Cheers,
Thorben

3

Thanks a lot. I can see how basic my mistake was now that I have read up on META-INF and META-INF/services. I had no idea about Java’s ServiceLoader functionality and thought I was configuring a feature of Camunda.

4