completely failed to read post data in vertx route handler chain - tried all ways no success - groovy

Question

i'm running a gradle build with vertx web. my library dependecies include
// for mock API serving https://mvnrepository.com/artifact/io.vertx/vertx-core
compile group: 'io.vertx', name: 'vertx-core', version: '3.5.3'
compile group: 'io.vertx', name: 'vertx-web', version: '3.5.3'
so in my groovy script code i do this
Vertx vertx = Vertx.vertx()
HttpServer server = vertx.createHttpServer()
...
I then declare a route to catch all requests on resource and process the request and form a response - trying to keep it simple - just return simple string as response
Router allRouter = Router.router(vertx)
allRouter.route ( "/api/now/table/incident")
.handler(BodyHandler.create())
.blockingHandler { routingContext ->
def request = routingContext.request()
HttpMethod method = request.method()
def response = routingContext.response()
response.putHeader ("content-type", "text/plain")
def uri = routingContext.request().absoluteURI()
switch (method) {
case HttpMethod.GET:
println "processing a resource GET on uri : $uri "
response.end ("(GET) howdi will")
break
case HttpMethod.POST:
String bodyEnc = routingContext.getBodyAsJson().encodePrettily()
println "processing a resource POST on uri : $uri"
println "post request received post data : " + bodyEnc
response.end ("(POST) howdi will")
break
}
}
I create a handler for BodyHandling, before the general handler in the route.
Then I start the server with the route
server.requestHandler(allRouter.&accept)
server.listen(8081, "localhost")
works all fine for a get request from postman.
when i use a post request with a request body data - the service hangs and i have to cancel - it never gets to the switch statement. All that happens in the console when i issue the post is
23:30:16.455 [vert.x-eventloop-thread-1] DEBUG io.netty.util.Recycler - -Dio.netty.recycler.maxCapacityPerThread: 32768
23:30:16.455 [vert.x-eventloop-thread-1] DEBUG io.netty.util.Recycler - -Dio.netty.recycler.maxSharedCapacityFactor: 2
23:30:16.455 [vert.x-eventloop-thread-1] DEBUG io.netty.util.Recycler - -Dio.netty.recycler.linkCapacity: 16
23:30:16.455 [vert.x-eventloop-thread-1] DEBUG io.netty.util.Recycler - -Dio.netty.recycler.ratio: 8
23:30:16.478 [vert.x-eventloop-thread-1] DEBUG io.netty.buffer.AbstractByteBuf - -Dio.netty.buffer.bytebuf.checkAccessible: true
23:30:16.482 [vert.x-eventloop-thread-1] DEBUG io.netty.util.ResourceLeakDetectorFactory - Loaded default ResourceLeakDetector: io.netty.util.ResourceLeakDetector#51d486
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I have tried this countless ways now, set bodyHandler inside the request when i get it etc - can't get it to work.
my postman post looks like this - where the headers are set to Content-Type application/json, Content-Length is 296 bytes (length of bytes in utf16), and Accept is text/plain to receive simple response
The documentation is just not clear. Blown 12 hours trying to crack this.
Does any one know exactly how one should get the post data on a request when using vertx web please

Answer 1

It appears as though my problem was the size of bytes being sent. I had calculated the bytes of the reqBody string as 296 bytes (using UTF16 charset), and set this into the Postman request.
So the vertx server was trying to read that many when processing the body and hanged. When I just did reqBody.getBytes().size - effectively UTF8, this returned 147 bytes. When I changed the content-length to this in postman, it started to work.
There is a timing issue in where you setup the BodyHandler. I tried this is tin the switch case, and it fails with request has already been read.
However neither of these seem to work successfully.
option 1 : ' create body handler before the route (path) call'
allRouter.route().handler(BodyHandler.create())
//now try and setup the route for API path interception
allRouter.route ( "/api/now/table/incident")
.blockingHandler { routingContext -> ...
option 2 : 'chain the handlers but put the Body Handler first'
//now try and setup the route for API path interception, followed by body handler
allRouter.route ( "/api/now/table/incident")
.handler(BodyHandler.create())
.blockingHandler { routingContext ->...
This was setting the content-length, assuming UTF16 for internal byte size that was the real problem. Now back to trying to complete what I set out to do.