Trying to figure out a way where I can pass some data/fields from a web page back into my application. This needs to works on Windows/Linux/Mac so I can't use a DLL or ActiveX. Any ideas?
Here's the flow:
1. Application gathers some data and then sends it to a web page using POST that is either imbedded in the app or pops up a new IE window.
2. The web page does some services and then needs to relay the results back to the application.
The only way to do this that I can think of is writing the results locally from the page in a cookie or something like that and have the application monitor for a specific file in that folder.
Alternatively, make a web service that the application hits after passing control to the page and when the page is done the web service will return the data. This sounds like it might have some performance drawbacks.
Can anyone suggest any better solutions for this?
Thanks
My suggestion:
Break the processing logic out of the Web Page into a seperate assembly. You can then create a Web Service that handles all of the processing without needing to pass control over to a page.
Your application can then call the Web Service directly and then serialize the results and work with the data quite easily.
Update
Since the page is supplied by a third party, you obviously can't break anything out. The next best thing would be to handle the entire web request internal to your application (rather than popping a new Window).
With this method, you can get the raw HTTP response (and page markup) and work with it directly. You can then parse the Response stream and gather the required data from it.
During performing an HTTP request you should be able to retrieve the text returned by the page. For instance, if your HTTP POST was to hit a Java servlet, the doPost() method would be fired and you would then perform your actions, you could then use the PrintWriter object from the Response object (PrintWriter out = response.getWriter();) and write text back to the calling application. I'm not sure this helps?
The fact that
web page is hosted by a third party
and they need to be doing the
processing on their servers.
is important to this question.
I like your idea of having the app call a webservice after it passes the data to the third-paty web page. You can always call the webservice asynchronously if you're worried about blocking your application while waiting for results from this webservice.
Another option is that your application implements an XML-RPC server that can be called from the web page using PHP, Python or whatever you use to build the website
A REST server will do the job also...
Related
So I have the following scenario (it's a Grails 2.1 app):
I have a Controller that can be accessed via //localhost:8080/myController
This controller in turn executes a call to another URL opening a connection using new URL("https://my.other.url").openConnection()
I want to capture the request so I can log the information
I have a Filter present in my web.xml already which does the job well for controllers mapped in my app. But as soon as a request is fired to an external URL, I don't get anything.
I understand that my filter will only be invoked to URLs inside my app, and that depends on my filter mapping which is fine.
I'm struggling to see how a solution inside the app is actually viable. I'm thinking of using a mixed approach with the DevOps team to capture such outgoing calls from the container and then log them into a separate file.
I guess my questions are:
Is there a way to do it inside the app itself?
Is the approach I'm planning a sensible one?
Cheers!
Any reason why you don't want to use http-builder? There a Grails plugin for it, and it makes remote XML calls much easier than handling the plumbing yourself. At the bottom of the linked page they describe how you can enable request logging via log4j configuration.
I am trying to implement basic progress bar for file uploads to work across multiple browsers without additional plugins like Flash or Silverlight. There are multiple ways to approach this problem on a client-side, however I can't find anything to work on a server.
Anywhere on MVC controller (before/on authorization and before/on executing action) file is already uploaded to server as HttpPostedFileBase. If I use basic HTTP handler for form submission, I have access to Context.Request.InputStream as well as to Context.Request.Files, but as soon I access the properties the stream/files would load silently.
I did extensive research, but could not find anything what allows me to Cache or store file upload process in Session. That would at least allowed me to use periodic AJAX requests from a client to monitor the progress.
What am I missing?
You should try a Javascript alternative, instead of handling it server side. The controller should only come in action when the request is done sending.
Try this JavaScript/jQuery alternative to Flash/SL
http://blueimp.github.io/jQuery-File-Upload/
I have an ASP.NET MVC application presenting some data and I want it to
open a new tab, or
redirect to a new view
when a web service gives me a signal. This WS is supposed to handle some external data and requests and when some specific action is called, I want it to be able to give my web application some kind of signal.
I was thinking about using Html.Action to an asynch controller but then I don't know how to provide the signal from the WS to the controller (or all instances of them).
Hopefully, it is understandable. Do you have an idea what needs to be done?
Thanks in advance.
So basically your problem comes down to the fact that server state is changed (through WS) and we want to make something happen at the client side where the your web app is being viewed.
Frankly it's not straightforward. Internet works on the Client -> Server architecture. User sends a request to the server, server responds. What you are trying to do is reverse of it. You want to send a request from server to user. HTTP protocol doesn't work like that.
Right now, to do something similar following two strategies are used:
Websockets : try searching them on google. You create a socket between the client and server and once server gets updated by the WS, it sends a request to the client through the socket. You can ask it to navigate to a different view or open a new window. The downside with it is that its not supported by the majority of the browsers. Might take a year or so to be. Not really recommend now.
Polling : You can make Ajax requests from your browser to server in certain intervals (you know like every 5 seconds) and see if the server state has changed or now. If yes, then do your stuff. That's the most common technique. Twitter.com uses it. There is also another version of it called Comet or Long Polling but I won't confuse you with that.
The important thing to note here is that whatever you want to do (open tab, change view etc) you have to do it through Javascript at the client side.
hope that helps
i have to develop a java-applet which redirects to another webpage. Normaly i use the "showDocument(URL ul)"-method to do that. But in this case i have to send a lot of data to this page. So i need to do it via POST. But showDocument just allows GET-method.
My question: Is it possible to do a redirect to another webpage from within a japplet AND to send POST Data in the same request (like showDocument() but with POST data)? - I know that i can do a POST request from within the applet - but this will happen in the applet's context.
It's a bit complicated because the script from which the applet is called, runs on a client-auth protected server. So i need to do the requests with the browser (because he will be authenticated) - if i do these requests from within the applet, the applet have to authenticate again...
thanx
daniel
Directly with the Java Applet API this is not possible - showDocument is the only thing you have, and it supports only GET. You may be able to do something like this with the JavaScript bridge (i.e. call javascript functions from the applet, which then send the POST request to the server like the browser would (and show the result in a new browser window), but I never used this.
I'm building ASP.NET MVC2 website that lets users store and analyze data about goods found on various online trade sites. When user is filling a form to create or edit an item, he should have a button "Import data" that automatically fills some fields based on data from third party website.
The question is: what should this button do under the hood?
I see at least 2 possible solutions.
First. Do the import on client side using AJAX+jQuery load method.
I tried it in IE8 and received browser warning popup about insecure script actions. Of course, it is completely unacceptable.
Second. Add method ImportData(string URL) to ItemController class. It is called via AJAX, does the import + data processing server-side and returns JSON-d result to client.
I tried it and received server exception (503) Server unavailable when loading HTML data into XMLDocument. Also I have a feeling that dealing with not well-formed HTML (missing closing tags, etc.) will be a huge pain. Any ideas how to parse such HTML documents?
Unfortunately you can't do cross-site loading usting JavaScript without using JSONP. This is a security issue. Your best bet would be to AJAX a request to one of your controller's actions and have it do the web request and return the result to the client.
As far as the 503 Server Unavailable goes, does this happen on every request? It sounds like you're parsing information from WoW Armory. They throttle web requests and will ban you after a certain about of time.
Use http://htmlagilitypack.codeplex.com/ to process HTML on server. Or regexps. Or string.IndexOf. Or import MSHTML via Interop library and use it. Do not load HTML into XML documents unless you're absolutely sure it's pure XHTML.
Also, try to see if 3rd party websites provide more direct access to data - XML, REST, web services.