Blazor WASM C# .NET 6 Content-Disposition is not Accessible - html

I'm extremely confused as I've been doing web development for many years now. Granted, this is my first time using Bazor and .NET 6.
Here's a screenshot of what I'm looking at:
Can someone please tell me why I can't get the content-disposition at all?
This should be trivial, but I tried logging all of the headers on the response and I just don't see anything.
My API is returning a file using File(Stream fileStream, string contentType, string? fileDownloadName) and you can see the filename in the response header.

I finally figured it out. I wasn't able to get ANY header value until I updated my API CORS Policy as follows:
You must expose the headers. I'm not sure why you can see the headers in the response, but Blazor can't, but that's what you have to do.

Related

Is there some kind of http validator?

I am writing a web service in node, and testing it with Postman. I spent a long timing looking for an error. When I finally found it, it turned out to be a simple error formatting the response body, which is json.
If I leave off the final brace in the response body, Postman waits for two minutes, and then reports that it received everything, just fine.
If I leave off the closing quote in the last value in the json, Postman says the server didn't respond, perhaps I should check my security certificates.
I would much rather Postman said "Hey, Buddy, you left off a quote!"
If there some validation service I can talk to? Or a plugin in Postman?
Here there are some validation javascript libraries, you can use:
Validator provides a declarative way of validating javascript objects.
Express-validator acts as an express.js middleware for node-validator.
Meanwhile, Postman got API testing and Collection Runner that can help you through this; which you can write some pre-request script as well as test script for each request.
Also, they got Newman which is a command-line collection runner. It allows you to effortlessly run and test a Postman collection directly from the command-line. It is built with extensibility in mind so that you can easily integrate it with your continuous integration servers and build systems.
I found that Paw worked (https://paw.cloud/). And so far I haven't paid for it.
Where Postman said "check your security certificates," Paw said "we were expecting 376 bytes but you only sent us 312."
Cuts down my time solving the problem a lot!
I use Fiddler for this. It is very good at identifying (with an error message that pops up) problems and bad implementations of the HTTP protocol. Browse the web with it running, and within a few minutes you'll undoubtedly hit a poorly implemented server.
Postman won't be able to handle these cases since it's insulated from poor behavior by the browser's framework.
That's not your problem though.
When I finally found it, it turned out to be a simple error formatting the response body, which is json.
That has absolutely nothing to do with HTTP. HTTP doesn't know or care what your request/response bodies are.
The problem you face is that your API endpoint could be returning whatever it wants. You need a custom solution to your problem, as there is no standard API server in this case.
Most folks will run unit tests that hit common endpoints of your service to ensure they're alive and well.
I should also point out that it should be all but impossible for you to break the JSON response if you're doing it correctly. Sounds like you're serializing JSON manually... never do that, we have JSON serializers for this purpose. Send in an object and let it worry about building the JSON output for you. Otherwise, you'll waste a lot of time on problems like these.

How to make request and send response on the network?

I am working on a JSON project and I basically want to hit on some specified URL with some request and get the response back. I want to know if there are some sites available that can provide me help for request, response on JSON?
Any sort of help is welcome!
Back when "Ajax" was being coined (and well before), we often used the XML HTTP Request object (W3 Schools) but web development is more mature now. Libraries such as jQuery wrap this functionality for easy use (jQuery Ajax)

How to specify mime-type in URL to specify JSON from RESTful web service

Can anyone tell me if it is possible to specify mime-type returned from a RESTful web service through the URL? I am trying to demo a simple service that I created to someone and I am just using a web browser (Chrome) to invoke the service. I am trying things like this:
http://localhost:8088/providers?mimeType={application/json}
http://localhost:8088/providers?mimeType=application/json
http://localhost:8088/providers?mimeType=json
None of these work for me - I just keep getting XML returned no matter what I select.
I found several posts related to this subject, but nothing with an answer about how to do this through a URL (I found some which talked about setting headers, but I am using a browser and don't have the ability to specify headers). I found this post:
REST Content-Type: Should it be based on extension or Accept header?
And that post linked to this: http://www.xml.com/pub/a/2004/08/11/rest.html
On the xml.com site, I found this text:
URI-Specified Representation [PS, AR]
A client can specify the representation using the following query string:
mimeType={mime-type}
A REST server should support this query.
So it seems that what I am trying to do should be possible, but I can't figure out how to make it work. Can anyone help?
Thanks.
To define the headers added to your request, you can use a Chrome extension like Postman.
Then you will be able to specify an Accept header to tell Talend to return json:
Accept: Application/json

WCF Data Services ODATA throwing error with JSONP

Ok so I have a WCF ODATA service hosted locally for testing purposes. Then I have a Kendo Grid trying to query the service using a Kendo Datasource configured for ODATA exactly like the demo!
On the deployed service, I also implemented the "JSONPSupportBehavior" attribute and class that everyone is talking about!
Still I get this in Fiddler : A supported MIME type could not be found that matches the acceptable MIME types for the request. The supported type(s) 'application/atom+xml;type=feed, application/atom+xml, application/json;odata=verbose' do not match any of the acceptable MIME types 'application/json'
Is this IIS issue now or something else? This is driving me crazy!
This is a change made in the WCF Data Services release. In order to get JSON response back (or JSONP) you need to send Accept header with value application/json;odata=verbose. Pure "application/json" is now reserved for the soon to be coming JSON Light format.
See http://blogs.msdn.com/b/astoriateam/archive/2012/04/11/what-happened-to-application-json-in-wcf-ds-5-0.aspx for more details.

Null JSON in getJSON response from IIS6, not IIS7? Using MVC2, jQuery, Ajax

New here. I've searched quite a bit for a working solution to my problem, but even though I have found posts with promising titles, none of the solutions have worked.
I am deploying an MVC2 web app to a client's server.
I did my development on Win2k8 Server, but they are running Win2k3 sever.
The app's only purpose is to receive some record ID information as HTTP parameters, check in the database for the status of the given record or records, and then return the status information as a simple string such as "Completed" or "Incomplete" in JSON format.
This getJSON code works fine in the development environment.
Inexplicably to me, on the client's server, the getJSON request receives a null response from the application.
There is no cross-domain action AFAIK... the result is the same from the client's server or from my machine via VPN.
In the MVC model's Json code, a common solution for people is to add the "JsonRequestBehavior.AllowGet" attribute to the Json result being returned. I did this long before trying to deploy it, and as I said, it has worked fine in the dev environment.
Using Firebug, I have watched the same request URL get sent to both my local server and the client server - the response headers from both servers are the same, but the response content from my server is shown as:
{"Result":"No Data"}
Which is what I want.
There is literally no content shown in the response from the client's server..? But the request gets an HTTP 200 code and is recorded as a success in the reponse's status attribute.
The response header content type in both situations is "application/json"
But wait, there is more!
If I manually enter the request to each server in the Firefox nav bar, and hit enter, in both cases it responds with:
{"Result":"No Data"}
Which is what I want. So why can I get the result I want from the MVC app on the client's server only when I hand-enter the request URL in Firefox, but not from the Javascript code?
I have tried forcing different output content types ... using the jQuery ajaxSetup method...
$.ajaxSetup({
async: false,
dataType: 'text'
});
or
$.ajaxSetup({
async: false,
dataType: 'html'
});
and again wtih 'script', and 'json'. I also tried the conversion options such as 'text json' or 'html json' or 'json text' and so forth.
Some of the posts I'm reading, and my gut feeling, though, suggest the problem is not the jQuery code making the request that is at fault... I don't see how the same jQuery request point to a different server running the same app would suddenly cause that server to send back a 'null' value.
By null, I want to be clear... I mean nothing is sent. There is no {} or {null} or any sign of JSON... just blank whiteness of non-existence :P
Even if nobody knows the answer, I would love some input perhaps suggesting where I should focus my sleuthing ... client or server?
If the problem is the server, it seems hard to really know that the MVC stuff is running 100% on the IIS6 server, but in general it seems to work. I have a different MVC app running on the client server which responds to the virtual paths, and generally runs the same as on dev machine.
I have found one thing ... the request headers are somewhat different? The Request Headers sent to the IIS7 setup include an "X-Requested-With: XMLHttpRequest", "referrer" , and "cookie" field/value.
I could guess that the lack of the "X-requested-with: XMLHttpRequest" in the IIS6 request headers is a clue, but I do not see then how the same javascript code pointing at a different server can generate different request headers itself. So how else are those being generated?
The javascript is embedded in an ASP.NET page, btw.
Oooh.. frustration!
Thanks for any input.
Odd Progress ... apparently there is some sort of issue with IIS6 handling the query. Although I have not payed any attention to JSONP, a post elsewhere suggested that sometimes use the "&callback=?" parameter at the end of a .getJSON request URL would force it into GET mode and that worked frequently for problems getting data from the server. So I did that... and it did work, sort of. The proper {"Result":"No Data"} was returned in response to the request... which seems good. However, the way that the JSONP callback works, it generates its own script to do the calling and fetching and interpreting of the incoming JSON. In this case, it interprets the JSON to need a label which it does not have, thus an error is thrown "invalid label" ... there must be some way to hack things to just deliver the JSON, but the whole required use of JSONP callbacks suggests that the server configuration is wrong, right? Or why does it work without JSONP for IIS7 and not IIS6?
Despite my not liking the callback JSONP solution, it appears to work ok. The error is still returned about an invalid label, but that does not appear to stop the remaining javascript from running... and so the application is working with IIS6 now. I have not tested the fix of using the callbacks and JSONP against IIS7 yet, but I expect it will work well enough.
Here is a link to the discussion that lead me to my current solution. I do still hope to find a more elegant solution, however.
NeoWin.net
Are you certain that your App Extension Mappings are set up correct?
Follow this article for running MVC2 on IIS6 and ensure all the different configurations have been done, that's probably the first step before going further and investigating specifics.
I'm really inclined to believe it's related to HTTP Verbs.