So, I've read a lot about using ExtJS's fileuploadfield to submit a form via an IFRAME. I understand that I'm supposed to reply with a JSON object indicating success or failure; fine. What I want to know is, how can I get more information back to the calling code? I don't want to simple send a file and say "yup, that worked fine" -- I want to submit a document, act on it, and return a result.
Say I have the user upload an XML document -- I might want to do a lookup or conversion based on it and update the contents of a form on my page accordingly. Is this even possible? I'd strongly prefer to avoid involving Flash or embedded applets if at all possible. If need be, I could even restrict this behavior to HTML5-compliant browsers...
I honestly thought I wasn't seeing the response I sent, but it was a server-side error. My success callback is now firing, with the full text of my server's response available as f.responseText (where f is the first argument to the success callback). My mistake!
Related
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 already checked the following links but they weren't much helpful (in parenthesis I've explained why it didn't work in my case as suggested in their answers)
Streams - hasOutOfBandMetadata and getStreamingMetadata (our content is already HLS)
Sonos player not calling GetStreamingMetadata (getMetdata is not called, only getMediaMetada is called since radio stream has unique id and is not a collection)
In Sonos API documentation it is mentioned that "hasOutOfBandMetadata" is deprecated and it is recommended that metadata be embedded inline with the content. However due to some limitations it can't be achieved in our service thus I have to go with the old way itself (whatsoever it is).
I suppose, ideally "getStreamingMetadata" should be called after setting "hasOutOfBandMetadata" to true but it's not happening.
Secondly, for testing purposes I set "secondsRemaining" and "secondsToNextShow" for different values to find out that "description" is also being displayed for those different time intervals (if I set secondsRemaining/secondsToNextShow to 20 then description is displayed for 20 seconds, if set to 200 then for 200 seconds and likewise). After the time lapses, information inside "description" disappears. So I guess there must be some call going to refresh metadata after the time lapses but couldn't figure out which call.
Kindly explain what is the proper way to get metadata for a continuous radio stream. On TuneIn radio you can find Radio Paradise for which metadata is getting updated as track changes. Even if they use metadata inline with their content there must be some way to achieve this.
Can you please post the calls and the the response that you are sending? This would help with troubleshooting this issue. Also what mimeType are you trying to use?
At this time the only full supported method for getting metadata for a continuous radio stream on Sonos that will be guaranteed to work in future releases is to embed metadata in line.
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
i'm trying to follow the example code on google's website here, but it seems a little broken - the javascript references getting a list of people from the server, but in the server-side code there's no reference to calling those functions of the api, it just returns an HTTP status code and a text status, so i'm wondering if there's a step missing and i'm exchanging the wrong code at the wrong time.
my current flow is
login button button clicked, magic happens, my callback gets passed an object with a whole bunch of properties in it
I take the code property from that object, and post it back to my server in an ajax request
on my server, i run the following python, where auth_code_from_js is the data of my post request:
oauth_flow = client.flow_from_clientsecrets('client_secrets.json', scope='')
credentials = oauth_flow.step2_exchange(auth_code_from_js)
python throws a FlowExchangeError with the message invalid request and no other useful information
am i missing a step? is that initial 'code' property what i'm supposed to be passing in to the 'step2_exchange' method?