I am new to Vertx, I am writing a proxy server, which will take request, update header, and send to another server. On receiving response, send the complete response as it is to client.
In vertx, Is there a way I do this straign forward or I need to implement handler for each http method and content type, to create new request and send using new client?
If you are using vertx-web of version 3.x and below, then you can do:
void redirect( RoutingContext rc, String url ) {
if( !rc.response().ended() )
rc.response().setStatusCode( 303 ).putHeader( 'Location', url ).end()
}
Related
In REST API, specifically RestAssured, there is an option to remove the Query params, Headers, Cookies, Form params, Path params which is set in request after getting a response.
Is there an option to remove the multipart content set in request in REST API(RestAssured) after getting a response?
If you're looking a way to reuse the RequestSpecification object, then No, there are no reset method for all of these config.
You can create new RequestSpecification object each time you call the request. Sample here. https://stackoverflow.com/a/69569031/7574461
I'm new to vert.x and I'm trying to create a simple download service.
I used Request#sendFile(fileName) and it works well, but if I pass a directory path to Request#sendFile(fileName) it throws an exception, which is totally fine.
The problem is that, even if I catch that exception with an handler, I can't send any data nor end the request, an that leaves the http client (the browser) stuck on an endless spinning progress.
That is an example that reproduces the problem:
VertxOptions options = new VertxOptions();
options.setBlockedThreadCheckInterval(1000*60*60);
Vertx vertx = Vertx.vertx(options);
HttpServer server = vertx.createHttpServer();
Router router = Router.router(vertx);
router
.route(HttpMethod.GET,"/foo")
.handler(ctx->{
// this path exist but is not a file, is a directory.
ctx.response().sendFile("docs/pdf",asr->{
if(asr.failed()) {
ctx.response()
.setStatusCode(404)
// I can't end the connection the only thing I can do is close it
// I've commented out this lambda because is not what I want to happen.
// It's just an hack to end the request all the same.
.end("File not found: "+"docs/pdf" /*, (x)->{ctx.response().close();}*/ );
}
});
});
server
.requestHandler(router)
.listen(3000);
I can this problem by checking first if the path references to a file which both exsist and is not a directory (which in fact I did in the real code), but that leaves me with doubt about what would happen if the IOException was something different (like reading a broken file, or an unauthorized file ...).
When this error happens no data is sent through the wire, I've both checked form the browser and sniffing packets TCP packets (0 bytes send from the server to the browser).
The only things that works is closing the connection with Response#close(), which at least closes the keep-alive http connection, and ends the browser request.
What I want to achieve is to send some information back to the client to tell something went wrong, possibly setting the status code to an appropriate 4** error and possibly adding some details to it (either in status text or in the response body).
You should add failureHandler to your router:
route.failureHandler(frc-> {
frc.response().setStatusCode( 400 ).end("Sorry! Not today");
});
see https://vertx.io/docs/vertx-web/java/#_error_handling
I need to read gzipped json payload in a POST request in my SPringBoot app which accepts json data. How to do that in order to keep the application generic as there may be other clients in future sending data in plain json or other compression formats? I suppose this should be handled by the server itself so is there any way to instruct the embedded Tomcat to unzip the payload?
My SpringBoot application runs on embedded Tomcat 9.0.17.
The controller accepts JSON payload in a POST request.
#RequestMapping(value = "/update/v1", method = RequestMethod.POST, produces = "application/json", consumes = "application/json")
public ResponseEntity<String> receiveUpdates(#RequestBody String update) {
We recently changed our content provider and the new one is sending payload in "gzip" format (with header content-encoding=gzip) and without any content-type header. As a result it gives the following error
'error': 'Unsupported Media Type', 'message': "Content type '' not supported"
If I change my consume type to MediaType.ALL_VALUE, my controller starts receiving the request but the payload itself is gzipped. I can handle it in my service layer but that would make it specific to gzipped data.
This problem could be solved by introducing a Filter to handle gzipped payload as mentioned here and here.
But I believe there should be a way to instruct the Tomcat to handle this and serve unzipped data.
I have an angular client which is making a POST call to my server. This server needs to get a response by calling another server(server2) with a POST call and pass the response from the server2 to the client. I tried the following approaches.
public Response call(){
String server2Url = "http://server2/path"
RestClient restClient = new RestClient();
return Response.fromResponse(restClient.post(server2Url)).build();
}
But in the above case the HTTP status code gets transferred but not the response body. The response body is empty
Then I tried:
public Response call() throws URISyntaxException{
String server2Url = "http://server2/path"
RestClient restClient = new RestClient();
return Response.temporaryRedirect(new URI(server2Url)).build();
}
but the browser client ends up making an OPTIONS call to the server2Url instead of a POST
and I tried.
public Response call() throws URISyntaxException{
String server2Url = "http://server2/path"
RestClient restClient = new RestClient();
return Response.seeOther(new URI(server2Url)).build();
}
but this ends up making a GET call instead of a POST.
How do I make the browser client make a POST call to server2
You can use Html Client from JAX-RS to make your own requests (from server1 to server2) and then return the response from server2 to the angular client.
public Response call() {
String url = "server2 url";
Response response;
try {
response = ClientBuilder
.newClient()
.target(url)
.request()
.post(Entity.json(null), Response.class);
}
catch (Exception e) {
// Whatever you want
return null; // or error
}
// Return the status returned by server 2
return Response.status(response.getStatus()).build();
}
What you are trying to accomplish is covered in the RFC 2616 I just found here.
If the 302 status code is received in response to a request other than GET or HEAD, the user agent MUST NOT automatically redirect the request unless it can be confirmed by the user, since this might change the conditions under which the request was issued.
So it looks like this is out of your hands if you´re not implementing the client.
Edit because I was told that RFC 2616 must not be used any longer.
RFC 7231 states that:
302 Found
The 302 (Found) status code indicates that the target resource
resides temporarily under a different URI. Since the redirection
might be altered on occasion, the client ought to continue to use the
effective request URI for future requests.
The server SHOULD generate a Location header field in the response
containing a URI reference for the different URI. The user agent MAY
use the Location field value for automatic redirection. The server's
response payload usually contains a short hypertext note with a
hyperlink to the different URI(s).
Note: For historical reasons, a user agent MAY change the request
method from POST to GET for the subsequent request. If this
behavior is undesired, the 307 (Temporary Redirect) status code
can be used instead.
What is:
307 Temporary Redirect
The 307 (Temporary Redirect) status code indicates that the target
resource resides temporarily under a different URI and the user agent
MUST NOT change the request method if it performs an automatic
redirection to that URI. Since the redirection can change over time,
the client ought to continue using the original effective request URI
for future requests.
The server SHOULD generate a Location header field in the response
containing a URI reference for the different URI. The user agent MAY
use the Location field value for automatic redirection. The server's
response payload usually contains a short hypertext note with a
hyperlink to the different URI(s).
Note: This status code is similar to 302 (Found), except that it
does not allow changing the request method from POST to GET. This
specification defines no equivalent counterpart for 301 (Moved
Permanently) ([RFC7238], however, defines the status code 308
(Permanent Redirect) for this purpose).
i'm new to Netty and intend to create a tcp socket server which reads the info of each client and replies back towards client before processing requests immediately ,i.e. sort of an acknowledgement towards client as and when the message enters overriden channelRead method of ChannelInboundHandlerAdapter class.
Please guide me in the above specified objective.
i'm currently trying the basic netty 4.1.4 echo server example however i wanted server to send back acknowledgement to the client so i updated channelread method as follows :
#Override
public void channelRead(ChannelHandlerContext ctx, Object msg) {
ctx.write(msg);
ChannelFuture cf = ctx.channel().write("FROM SERVER");
System.out.println("Channelfuture is "+cf);
}
and the output obtained was as follows:
Channelfuture is DefaultChannelPromise#3f4ee9dd(failure: java.lang.UnsupportedOperationException: unsupported message type: String (expected: ByteBuf, FileRegion))
I understand the error that it is expecting bytebuf but how do i achieve it? also, whether this method would be able to send out acknowledgement towards client
You can use String.getBytes(Charset) and Unpooled.wrappedBuffer(byte[]) to convert to ByteBuf.
ChannelFuture cf = ctx.channel()
.write(Unpooled.wrappedBuffer("FROM SERVER".getBytes(CharsetUtil.UTF_8)));
Also note that ctx.channel().write(...); may not be what you want. Consider ctx.write(...); instead. The difference is that if your handler is a ChannelDuplexHandler it would receive a write event when you do channel().write(). Using ctx instead of channel will send the write out from your handlers point in the pipeline instead of from the end of the pipeline, which is usually what you want.