Just wondering if there is anyway to save data across the line without the response coming back. i.e. Im using the objc odata sdk. If I create an employee entity on the ipad, than I save it, I dont need to receive the the saved entity back. So really its sending the data across the line than returning it for no reason. Only really need to send it across.
Any ideas on how I can set saves to be push to server and not have to wait for the return?
Thanks in advance
In the latest CTP (http://blogs.msdn.com/b/astoriateam/archive/2011/10/13/announcing-wcf-data-services-oct-2011-ctp-for-net-4-and-silverlight-4.aspx) you can use the Prefer header. The client can send the request with Prefer header set to return-no-content and the server will send an empty response back. The header is described here: https://datatracker.ietf.org/doc/html/draft-snell-http-prefer-01.
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I'm trying to send xAPI statements from an "Activity Provider" to the ADL LRS live demo. The goal is to implement this from my C# .NET application, but I was having trouble implementing it so I tried running a simple POST request from JMeter.
I do get a 200 response, but when I try to check whether the statement was successfully stored at https://lrs.adlnet.gov/me/statements, it's empty.
Am I completely misunderstanding how this structure is supposed to work? I'm going to install the ADL LRS eventually for testing purposes, but I wanted to get the actual request structure worked out first.
The path looks incorrect, the POST should be to {endpoint}/statements, so in your case it looks like it should be https://lrs.adlnet.gov/xAPI/statements. Additionally you should make sure you are setting the X-Experience-API-Version header. If this doesn't solve the issue, you should look at more than just the response status code, and see what the body contains (and add it to your question). The body for the type of request you are sending should return JSON, with an array with a single statement identifier in it. Additionally when you retrieve the statements the URL you use should match the one that you specify when you send, so /me/ is not correct.
If it is a basic C# .NET project you may be interested in https://github.com/RusticiSoftware/TinCan.NET. It is showing its age, but in general for a number of projects it will still work or would at least be a reasonable place to start.
I am designing my first REST API.
Suppose I have a (SOAP) web service that takes MyData1 and returns MyData2.
It is a pure function with no side effects, for example:
MyData2 myData2 = transform(MyData myData);
transform() does not change the state of the server. My question is, what REST call do I use? MyData can be large, so I will need to put it in the body of the request, so POST seems required. However, POST seems to be used only to change the server state and not return anything, which transform() is not doing. So POST might not be correct? Is there a specific REST technique to use for pure functions that take and return something, or should I just use POST, unload the response body, and not worry about it?
I think POST is the way to go here, because of the sheer fact that you need to pass data in the body. The GET method is used when you need to retrieve information (in the form of an entity), identified by the Request-URI. In short, that means that when processing a GET request, a server is only required to examine the Request-URI and Host header field, and nothing else.
See the pertinent section of the HTTP specification for details.
It is okay to use POST
POST serves many useful purposes in HTTP, including the general purpose of “this action isn’t worth standardizing.”
It's not a great answer, but it's the right answer. The real issue here is that HTTP, which is a protocol for the transfer of documents over a network, isn't a great fit for document transformation.
If you imagine this idea on the web, how would it work? well, you'd click of a bunch of links to get to some web form, and that web form would allow you to specify the source data (including perhaps attaching a file), and then submitting the form would send everything to the server, and you'd get the transformed representation back as the response.
But - because of the payload, you would end up using POST, which means that general purpose components wouldn't have the data available to tell them that the request was safe.
You could look into the WebDav specifications to see if SEARCH or REPORT is a satisfactory fit -- every time I've looked into them for myself I've decided against using them (no, I don't want an HTTP file server).
I have a subroutine in my Controller
<HttpPost>
Sub Index(Id, varLotsOfData)
'Point B.
'By the time it gets here - all the data has been accepted by server.
What I would like to do it capture the Id of the inbound POST and mark, for example, a database record to say "Id xx is receiving data"
The POST receive can take a long time as there is lots of data.
When execution gets to point B I can mark the record "All data received".
Where can I place this type of "pre-POST completed" code?
I should add - we are receiving the POST data from clients that we do not control - that is, it is most likely a client's server sending the data - not a webbrowser client that we have served up from our webserver.
UPDATE: This is looking more complex than I had imagined.
I'm thinking that a possible solution would be to inspect the worker processes in IIS programatically. Via the IIS Manager you can do this for example - How to use IIS Manager to get Worker Processes (w3wp.exe) details information ?
From your description, you want to display on the client page that the method is executing and you can show also a loading gif, and when the execution completed, you will show a message to the user that the execution is completed.
The answer is simply: use SignalR
here you can find some references
Getting started with signalR 1.x and Mvc4
Creating your first SignalR hub MVC project
Hope this will help you
If I understand your goal correctly, it sounds like HttpRequest.GetBufferlessInputStream might be worth a look. It allows you to begin acting on incoming post data immediately and in "pieces" rather than waiting until the entire post has been received.
An excerpt from Microsoft's documentation:
...provides an alternative to using the InputStream propertywhich waits until the whole request has been received. In contrast, the GetBufferlessInputStream method returns the Stream object immediately. You can use the method to begin processing the entity body before the complete contents of the body have been received and asynchronously read the request entity in chunks. This method can be useful if the request is uploading a large file and you want to begin accessing the file contents before the upload is finished.
So you could grab the beginning of the post, and provided your client-facing page sends the ID towards the beginning of its transmission, you may be able to pull that out. Of course, this would be reading raw byte data which would need to be decoded so you could grab the inbound post's ID. There's also a buffered one that will allow the stream to be read in pieces but will also build a complete request object for processing once it has been completely received.
Create a custom action filter,
Action Filters for executing filtering logic either before or after an action method is called. Action Filters are custom attributes that provide declarative means to add pre-action and post-action behavior to the controller's action methods.
Specifically you'll want to look at the
OnActionExecuted – This method is called after a controller action is executed.
Here are a couple of links:
http://www.infragistics.com/community/blogs/dhananjay_kumar/archive/2016/03/04/how-to-create-a-custom-action-filter-in-asp-net-mvc.aspx
http://www.asp.net/mvc/overview/older-versions-1/controllers-and-routing/understanding-action-filters-vb
Here is a lab, but I think it's C#
http://www.asp.net/mvc/overview/older-versions/hands-on-labs/aspnet-mvc-4-custom-action-filters
For a RESTful API that I'm creating, I need to have some functionality that get's a resource, but if it doesn't exist, creates it and then returns it. I don't think this should be the default behaviour of a GET request. I could enable this functionality on a certain parameter I give to the GET request, but it seems a little bit dirty.
The main point is that I want to do only one request for this, as these requests are gonna be done from mobile devices that potentially have a slow internet connection, so I want to limit the requests that need to be done as much as possible.
I'm not sure if this fits in the RESTful world, but if it doesn't, it will disappoint me, because it will mean I have to make a little hack on the REST idea.
Does anyone know of a RESTful way of doing this, or otherwise, a beatiful way that doesn't conflict with the REST idea?
Does the client need to provide any information as part of the creation? If so then you really need to separate out GET and POSTas otherwise you need to send that information with each GET and that will be very ugly.
If instead you are sending a GET without any additional information then there's no reason why the backend can't create the resource if it doesn't already exist prior to returning it. Depending on the amount of time it takes to create the resource you might want to think about going asynchronous and using 202 as per other answers, but that then means that your client has to handle (yet) another response code so it might be better off just waiting for the resource to be finalised and returned.
very simple:
Request: HEAD, examine response code: either 404 or 200. If you need the body, use GET.
It not available, perform a PUT or POST, the server should respond with 204 and the Location header with the URL of the newly created resource.
Using HttpWebRequest/Response, and the Trailer headers in the chunked-encoded response are being thrown away (I've actually stepped through the .Net 4.0 reference source to see where it calls RemoveTrailers after the final chunk). Is there any way to retrieve those headers? Also, does anyone know why this behavior is in place to begin with?
In case anyone asks, no, I can't ensure that the trailer headers are moved to the rest of the headers. This is simply the data stream format I have to work with.
I dont think there is any way to do that. As to why it is like this, when this feature was first being implemented, there was no known HTTP server that sent headers in chunked response trailers.
What kind of server is this? Is this a custom server that is doing this?
If you absolutely care about this, you can find a feature request at the MS connect website (http://connect.microsoft.com).