Local request context in GWT - gwt

In Java, there is ThreadLocal, which can be used to carry some data from one object to another without explicit passing as method argument.
I need to intercept GWT request and extract custom HTTP header from it, then I need to store the header value somehow to be processed later.
The problem is that the place to extract the header belongs to RequestBuilder, and there is no way (?) to pass the variable from within RequestBuilder to the custom code actually handling the request/response from server. And it is not possible to pass some variable from client code to that request builder.
ThreadLocal could be the solution, however it is not available in GWT. Is there something I can use?

You can use RequestBuilder.setHeader to set header values for your HTTP request.
On the backend you can use HttpServletRequest of your servlet to retrieve the header values from your HTTP request.
Update:
Some class with a static instance variable:
public class SomeClass {
public static String myVar;
}
And in the RequestBuilder code you can do following:
RequestBuilder request = new RequestBuilder(url);
request.setCallback(new RequestCallback() {
#Override
public void onResponseReceived(Request request, Response response) {
SomeClass.myVar = response.getHeader("someheader");
}
});

Related

How to access suffixes using HTL/Sightly?

TLDR: Create a new AEM page called "mypage.html". Supply suffixes in the URL. Pass this suffixes to an Sling servlet. The suffixes act as URL parameters.
sample desired URL: http://localhost:4502/mypage.html/john/smith
So I created a servlet (used this guide: http://www.aemcq5tutorials.com/tutorials/sling-servlet-in-aem/) that can read a suffix.
#SuppressWarnings("serial")
#SlingServlet(paths="geometrixx/components/hompepage", selectors="name", extensions="html",methods="GET", metatype=true)
public class StaffProfileServlet extends SlingAllMethodsServlet {
private static final Logger log = LoggerFactory.getLogger(CourseBookmarkServlet.class);
#Override
protected void doGet(final SlingHttpServletRequest request,
final SlingHttpServletResponse response) throws ServletException, IOException {
RequestPathInfo rpi = request.getRequestPathInfo();
String[] suffixes = rpi.getSuffix().split("/");
and it working fine if I access it via http://localhost:4502/content/geometrixx/en.name.html/first/last
What I want to do next is create a new page called "mypage.html" and supply first and last as suffixes.
mypage will display information relevant to the person in a properly formatted page. With code above, all I get is JSON response.
Some assumptions/changes which I think is needed to achieve my goal:
I will be using paths and using request parameters (i.e. using request.getParameter("myparameter") on servlet code
I will be using AJAX to access the servlet
If my assumptions are correct, how do I access suffixes from HTL/Sightly? I understand I can get the URI via ${request.requestURI} or even Javascript. And using this value, I can then use this in my AJAX call.
But is this the AEM/Sling way of doing it? Or perhaps there is a better way to do what I want?
Thanks a lot!
You can use RequestPathInfo interface from HTL to access suffix's. ${request.requestPathInfo.suffix}
Global objects accessible through HTL -> here.
Methods accessible through request object -> here.

How to Pass object to REST Get Method

I am using Jersey Rest implementation. There are one Rest Services Called HelloWorld. See the below code.
Please consider this code as reference not as compiled code.
#Path("helloWorld")
public class HelloWorld{
#Path("test")
#Produces(...)
#Consum(...)
#GET
public Response test(Person person){
System.out.println(person);
}
}
I am using Jersey client to sent the request.
Here My question is apart from POST method is there any way to send the object to GET method directly. Instead of QueryString.
Please let me if there is any way to do so.
Thanks
So the problem shouldn't be with the server. I did a few tests on different servers (not weblogic as I don't use it) and all of them seem to have no problems accepting a body in the GET request. The problem seem to be with the client. To test I used the following code
ClientBuilder.newClient()
.target("http://localhost:8080/api/get-body")
.property(ClientProperties.SUPPRESS_HTTP_COMPLIANCE_VALIDATION, true)
.request()
.method(HttpMethod.GET, Entity.text("Hello World"));
The SUPPRESS_HTTP_COMPLIANCE_VALIDATION allows us to pass a body to the request. If we didn't use this, then we would get an error.
The problem with this code, is that even though we set this override property, the client completely overrides the GET method and automatically makes it a POST method, so I would get back a 405 Method Not Allowed.
The solution I came up with is to just allow the client to set a header, e.g. X-GET-BODY-OVERRIDE, and then use a #PreMatching filter on the server side to check for this header. If the header is present, then just change the method to a GET
#Provider
#PreMatching
public class GetWithBodyFilter implements ContainerRequestFilter {
#Override
public void filter(ContainerRequestContext request) throws IOException {
String getOverride = request.getHeaderString("X-GET-BODY-OVERRIDE");
if (getOverride != null && "true".equalsIgnoreCase(getOverride)) {
request.setMethod(HttpMethod.GET);
}
}
}
Then just register the filter with the server side. On the client, you would simply need to add the header
ClientBuilder.newClient()
.target("http://localhost:8080/api/get-body")
.property(ClientProperties.SUPPRESS_HTTP_COMPLIANCE_VALIDATION, true)
.request()
.header("X-GET-BODY-OVERRIDE", "True")
.method(HttpMethod.GET, Entity.text("Hello World"));
This solution is good because it takes into account more than just the Jersey client, in regards with being able to send a body in the GET request.

How to produce rendered output from a Sling POST in AEM?

It seems like Sling expects every form POST to modify the JCR. So the expected/standard behavior would be a POST-redirect-GET, which is fine for most things. However, I need to be able to POST to AEM and then use the data in that POST to create a rendered result. Our use of AEM is stateless and so I don't want to carry the POST'd data in Session in order to utilize it in a subsequent GET.
Some have recommended putting the POST'd data in Browser sessionStorage, but that doesn't have broad enough support to be sufficient.
As far as I can tell there is no way for Sling in AEM to take a POST and produce a rendered result.
Here is a screenshot of what a POST produces in the page/resourceType component and in any Sling included jsp's that happen to be involved in the rendering.
I have tried things like using the "nop" operation.
<input type="hidden" name=":operation" value="nop" />
But either way all servlets think a POST is happening and don't render properly.
There is the option of creating a custom servlet, to handle the POST, but then how do you render the templated output and change the request so that all the components think they are serving a GET?
UPDATED:
Here is a screenshot of the "nop" POST.jsp result.
What you can do is create a POST.jsp file in the appropiate resourceType.
If your POST request go to /content/yourapp/something, which has a resourceType: your/app/example. Then you can create a file /apps/your/app/example/POST.jsp with whatever render you wish. You can even include your default rendering script in the POST.jsp file if you need it to be rendered the same as the GET requests.
The other option is to use a servlet registered for POST requests and internally use the SlingRequestProcessor service. That service allow you to programmatically process a request through Sling. You can use a SlingRequestWrapper to wrap your request and override getMethod() to return "GET". That should process the request as if it was a GET request.
This sounds like a somewhat funky use case, IIUC you are using a large request parameter P to drive the rendering?
Using a custom POST servlet should work, if you use something like
slingRequest.getRequestDispatcher(resource).forward(request, response) where request is a wrapper around the actual request, where request.getMethod() returns GET. You can then store your P data in request attributes.
The SlingHttpServletRequestWrapper class can be used to create such wrappers.
Creating a custom servlet to handle a post could be an idea. After successfull write you could redirect to the modified resource - simple 302.
The other solution that comes to my mind is a custom Filter that would do the same. However, since AEM expects to get 200 instead of 302, it would be good to tell by atrribute or parameter that this POST needs to be redirected. Otherwise some of the AEM UI functionalities could brake. This is a quick example of an idea. You would probably need to write something more sophisticated.
#Component(immediate = true)
#Service
#Properties({
#Property(name = Constants.SERVICE_DESCRIPTION, value = "Desc"),
#Property(name = Constants.SERVICE_VENDOR, value = "Company name"),
#Property(name = Constants.SERVICE_RANKING, intValue = RedirectFilter.RANKING),
#Property(name = "filter.scope", value = "request") })
public class RedirectFilter implements Filter {
public static final int RANKING = -1000; // low ranking
#Override
public void init(final FilterConfig filterConfig) throws ServletException {
}
#Override
public void destroy() {
}
#Override
public void doFilter(final ServletRequest request, final ServletResponse response, final FilterChain chain)
throws IOException, ServletException {
if (request.getParameter("redirect").equals("true")) {
((SlingHttpServletResponse) response).sendRedirect(((SlingHttpServletRequest)request).getRequestURI());
}
}
}

GWT JSONPRequestBuilder - "Unknown Token :" error in browser console with Timeout exception at the end

I am trying to call a Restful WS from GWT using JSOPRequestBuilder. I have a similar issue which was reported in the link
http://groups.google.com/group/google-web-toolkit/browse_thread/thread/ef93383aca7a3dfc/d4dc5bad1a9110ea
But, I could not figure out the solution. Kindly help me at the earliest.
My JAX-WS resource code snippet from server
#GET
#Produces(MediaType.APPLICATION_JSON)
public DealerAddress getDealerAddress(#QueryParam("dealerId") String sDealerId) {
DealerAddress dlrAd = new DealerAddress("test", "test", "test", "test", 10, new Date(), new Date());
return dlrAd;
}
Jersey returns a JSON object of DealerAddress.
Now rest URL "https://127.0.0.1:8181/application/rest/OrderManagementResource?alt=json-in-script&dealerId=DLR1"
works absolutely fine when i tried request in browser.
It even works with RequestBuilder approach from GWT but not with JSONPRequestBuilder approach.
Code snippet to invoke WS from GWT using JSONPRequestBuilder
JsonpRequestBuilder jsonPReqBuilder = new JsonpRequestBuilder();
jsonPReqBuilder.setTimeout(100000);
jsonPReqBuilder.setCallbackParam("callback");
jsonPReqBuilder.requestObject("https://127.0.0.1:8181/application/rest/OrderManagementResource?alt=json-in-script&dealerId=DLR1" , new AsyncCallback<DealerAddressJSON>() {
#Override
public void onFailure(Throwable caught) {
// TODO Auto-generated method stub
caught.printStackTrace();
Window.alert("Inside error"+caught.getLocalizedMessage());
}
#Override
public void onSuccess(DealerAddressJSON result) {
// TODO Auto-generated method stub
Window.alert("Inside success"+result);
}
});
where as DealerAddressJSON is a JavaScriptObject type class.
I could see that my JAX Rest resource getting called and saying returning from server.
Also, I could see that in Firebug that the response comes in browser but fails with an exception "Unknown token :"
At the end I always get a Timeout exception.
Now I am in big question whether the way we return JSON from JAX-RS resource is a problem in server
or
JSONPRequestBuilder calling procedure is a problem? I could not understand the callback changes which some of the links explained on this issue.
Kindly help me.
You are probably sending back JSON, while the JSONPRequestBuilder expects JSONP. These are not the same thing.
JSON is just the data, as is - make the request using AJAX (i.e. the RequestBuilder), and the contents can be read directly. These requests can only be made to the same server. Example JSON data:
{"response":"success", "items":[{"id":1}, {"id":2}]}
In contrast, JSONP is designed for cross-origin requests, so instead of just containing the data, the data is wrapped up in a JavaScript. Since your JSON service isn't wrapping the a response in a js function call, this isn't working. Example JSONP data:
callback_1({"response":"success", "items":[{"id":1}, {"id":2}]})
The callback changes with each request, so the server is supposed to change that callback function based on what the client requested each time.

adding http headers in call to SoapHttpClient service

I have to consume a service provided by one of our partners. I was given little direction, but was told the security was to be PasswordDigest. I looked it up and immediatly saw lots of references to WSE, so off I went. It was very easy to implement and in no time I had a standard WSE user token using PasswordDigest sitting in the SOAP headers of my messages.
When we started testing today I was immediatly told (by the error message) that things weren't right. Turns out, out partner doesn't look in the SOAP header, but rather wants the security info in the http header.
I have seen lots of articles on how to add custom http headers to a proxy class, but my proxy inherits from SoapHttpClientProtocol which doesn't have a headers collection to add to. I was looking at making a raw httpWebRequest, but I have a specific method to access that has some complex parameters to deal with (and besides it feels like going backwords).
What is the best way to add custom http headers to a service proxy class that doesn't have a GetWebRequest method?
For reference:
Proxy class decleration:
[System.CodeDom.Compiler.GeneratedCodeAttribute("System.Web.Services", "2.0.50727.3053")]
[System.Diagnostics.DebuggerStepThroughAttribute()]
[System.ComponentModel.DesignerCategoryAttribute("code")]
[System.Web.Services.WebServiceBindingAttribute(Name="MtomServiceSoap11", namespace="http://ws.xxxxxxx.com/")]
public partial class MtomServiceService : System.Web.Services.Protocols.SoapHttpClientProtocol {
Target method I need to call:
[System.Web.Services.Protocols.SoapDocumentMethodAttribute("", Use=System.Web.Services.Description.SoapBindingUse.Literal, ParameterStyle=System.Web.Services.Protocols.SoapParameterStyle.Bare)]
[return: System.Xml.Serialization.XmlElementAttribute("uploadDocumentResponse", Namespace="http://ws.edsmtom.citizensfla.com/")]
public uploadDocumentResponse uploadDocument([System.Xml.Serialization.XmlElementAttribute(Namespace="http://ws.xxxxxxx.com/")] uploadDocumentRequest uploadDocumentRequest) {
object[] results = this.Invoke("uploadDocument", new object[] {
uploadDocumentRequest});
return ((uploadDocumentResponse)(results[0]));
}
}
The actual call to the Service is simple. The objects being pass in are not:
request.criteria = docCriteria;
request.document = document;
var result = service.uploadDocument(request);
Thanks.
It figures that 30 minutes after posting I would stumble across the answer. While the proxy class decelaration does not create a GetWebRequest method, its base class System.Web.Services.Protocols.SoapHttpClientProtocol has it and it can be overridden.
protected override System.Net.WebRequest GetWebRequest(Uri uri)
{
var request = base.GetWebRequest(uri);
request.Headers.Add("blah", "blah"); // <----
return request;
}