Camel Karavan : Servlet as component to rest configuration.

[MN-Dheeraj]

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I am adding my spring boot code to karavan to build route of an API. In my code, there is a common class for route builder that has this line.
restConfiguration().component("servlet");

I see that servlet is being added as component to the rest configuration. So, I tried to do that on karavan by going to REST>Create configuration and selected the component as servlet from the dropdown.
I get this error however.

Error:

2024-04-23 04:23:25.089 WARN 15 --- [ ReloadOnDemand] support.RouteOnDemandReloadStrategy : Error reloading routes due to Failed to create route route-a27c: Route(route-a27c)[From[rest:post:/LoanAccountDetails] -> [pr... because of Failed to resolve endpoint: rest://post:/LoanAccountDetails due to: No RestConfiguration for component: platform-http found, RestConfiguration targets: servlet. This exception is ignored.
org.apache.camel.FailedToCreateRouteException: Failed to create route route-a27c: Route(route-a27c)[From[rest:post:/LoanAccountDetails] -> [pr... because of Failed to resolve endpoint: rest://post:/LoanAccountDetails due to: No RestConfiguration for component: platform-http found, RestConfiguration targets: servlet
at org.apache.camel.reifier.RouteReifier.createRoute(RouteReifier.java:85) ~[camel-core-reifier-4.4.0.jar:4.4.0]
at org.apache.camel.impl.DefaultModelReifierFactory.createRoute(DefaultModelReifierFactory.java:49) ~[camel-core-engine-4.4.0.jar:4.4.0]
at org.apache.camel.impl.DefaultCamelContext.startRouteDefinitions(DefaultCamelContext.java:728) ~[camel-core-engine-4.4.0.jar:4.4.0]
at org.apache.camel.impl.DefaultModel.addRouteDefinitions(DefaultModel.java:249) ~[camel-core-engine-4.4.0.jar:4.4.0]

Here is my route on karavan.

• route:
  id: route-a27c
  nodePrefixId: route-06e
  from:
  id: from-1df0
  uri: rest
  parameters:
  method: post
  path: /LoanAccountDetails
  steps:
  - process:
  id: process-d06b
  description: Interception and logging to DB
  ref: Esbloginterceptorprocessor
  ------other steps----------

Can someone please guide me in adding servlet as component? I tried adding 'Consumer Component Name' of my 'from' REST component on my route itself. But, it doesn't work. When I make my API call, I get 404. Without, this modification, it works fine.

Variant

Web Application

Container Management (if applicable)

Docker

Operating System (if applicable)

Windows

Version

4.4.0

[davsclaus]

do not use servlet, you should use platform-http which is the default, so you do not have to configure it.

[MN-Dheeraj]

Hi @davsclaus ,

Do you mean to say that adding servlet as component doesn't work at all?
Actually, In my camel-springboot code, this happens

HttpServletRequest req = exchange.getIn(HttpServletRequest.class);
String remoteAddr = null;
if (req != null) {
remoteAddr = req.getRemoteAddr();
String method = Exchange.HTTP_METHOD;
apiLogDetail.setServiceName(apiName);
apiLogDetail.setEndPoint(req.getRequestURL().toString());
//saving apiLogDetail to DB
}

I am getting req as null probably because I commented this line because of the above mentioned issue.
restConfiguration().component("servlet");

When you say 'don't use servlet', do you suggest any alternative or that there is no provision to use it on karavan at all?

[davsclaus]

karavan comes with platform-http as its supported http server, so use that

[MN-Dheeraj]

This is my code.

HttpServletRequest req = exchange.getIn(HttpServletRequest.class);
remoteAddr = req.getRemoteAddr();
String url = req.getRequestURL().toString();

If servlet can't be used, the request would obviously be null.
Can you suggest an alternative logic in case of platform-http?

My code is in spring boot.

[MN-Dheeraj]

@davsclaus ,

I see that I can create rest configuration on karavan. In the list of the dropdown on the component, I see 'servlet' also. May I know how this works?

[davsclaus]

Karavan ui is ALL of camel and shows everything - also older http servers like jetty and coap for mqtt protocols.
But when you run in karavan web it runs only in vanilla camel standalone, and platform-http is only supported there (auto detected so you dont need to select anyway).

[MN-Dheeraj]

I have this in Vscode as well. Is it not possible there as well?

Also, I will mark it as answer myself, once it is fully clarified.