Using HTTP client to send requests, it is found that request HTTP header is all lowercase.

[fly512]

Using HTTP client to send requests, it is found that request HTTP header is all lowercase.
Such a part of the server will reject my request
How to correct the repair

[jonahwilliams]

@fly512 Which HttpClient are you using - dart:io or package:http?

[jonahwilliams]

Also field headers are case insensitive, per my understanding of http

[zoechi]

Looks like a dup of dart-lang/sdk#25120

[fly512]

I read the IO Library of dart
https://github.com/dart-lang/sdk/blob/0b58c4bd10df3f41baa19b1dc2aa25c76137b09c/sdk/lib/_http/http_headers.dart#L44

[zoechi]

@fly512 it's intentional. The server you are using is not HTTP compliant.

[fly512]

@zoechi I think so, but we can't control the header sent by HTTP, which sounds strange. Or do I need to use socket to handle it on my own? But it may take a long time, and it may not be reliable.

[zoechi]

You are not supposed to influence casing of headers because according to the standard it needs to be ignored.

[boapps]

I also have the same problem and I tried contacting the support, but they didn't want change the headers, so now I have to make it work somehow. Can I modify Flutter source files so the headers are case-sensitive, or write a plugin for that, or create a plugin that uses the native (Java/Swift) HTTP requests, because I know that Android's HttpsURLConnection uses case-sensitive headers, not sure about Swift though.

[zoechi]

@boapps They shouldn't need to change their headers.
They should change their code to accept headers independent of casing according to the HTTP standard.

Sure, you can create a Flutter plugin that uses native Android or iOS implementations.
There is no way to change the Flutter source. This functionality is part of the Dart SDK.

[boapps]

@zoechi Thanks for the reply sorry for bad wording, I contacted them and I actually asked them to make their headers case-sensitive and told them that their API is not HTTP compliant, nothing changed and got a template response (to be fair, I am creating an unofficial client app for the official Hungarian-school-evaluation-management-system thing and their API was not documented anywhere, I discovered it with wireshark).
I will try implementing native HTTP requests with a plugin then, I might also open-source it and maybe share progress here, thanks for the help!

[zoechi]

I'm going to close this because I there is nothing the Flutter team can do.

[catalin260]

@zoechi Thanks for the reply sorry for bad wording, I contacted them and I actually asked them to make their headers case-sensitive and told them that their API is not HTTP compliant, nothing changed and got a template response (to be fair, I am creating an unofficial client app for the official Hungarian-school-evaluation-management-system thing and their API was not documented anywhere, I discovered it with wireshark).
I will try implementing native HTTP requests with a plugin then, I might also open-source it and maybe share progress here, thanks for the help!

Hello @boapps ,

Did you find a solution for this problem? I'm in the same problem as you described here.

[boapps]

@catalin260 I wrote a plugin that could do simple http push and get requests. Nothing special, it just passes some headers and a URL to the Android HttpURLConnection then returns the result text. It only works for Android. But I don't use it, because I found a workaround the initial problem.

[gsy13213009]

What? the bug is closed? So what can we do to keep the header?

[ghost]

@boapps whats is the workaround?

[cdm2012]

Creating an API Client using HTTPClient with the following request headers:

I/flutter (32611): headers: {
I/flutter (32611):   "Content-type": "application/json",
I/flutter (32611):   "Accept": "application/json",
I/flutter (32611):   "Authorization": "Bearer: E7HlYmfiXwhLQT1nYApOAE4wqhvCZZXndrT7kiRv8tUBycj3npVnYwnQnH34"
I/flutter (32611): }
I/flutter (32611): 
I/flutter (32611): 
I/flutter (32611): 
I/flutter (32611): request.headers: 
I/flutter (32611): content-type: application/json
I/flutter (32611): accept: application/json
I/flutter (32611): authorization: Bearer: E7HlYmfiXwhLQT1nYApOAE4wqhvCZZXndrT7kiRv8tUBycj3npVnYwnQnH34

And the server (nginx/1.15.8) is returning a 400 error:

I/flutter (32611): <html>
I/flutter (32611): <head><title>400 Bad Request</title></head>
I/flutter (32611): <body>
I/flutter (32611): <center><h1>400 Bad Request</h1></center>
I/flutter (32611): <hr><center>nginx/1.15.8</center>
I/flutter (32611): </body>
I/flutter (32611): </html>

Using the same headers in android with the following request headers:

E: Called doInBackground w/ headers: [Accept: application/json, Content-type: application/json, Authorization: Bearer E7HlYmfiXwhLQT1nYApOAE4wqhvCZZXndrT7kiRv8tUBycj3npVnYwnQnH34]

And the same server is returning a 200 response, so I'm really looking forward to integrating the change by @zichangg : dart-lang/sdk#39657 (comment)

See Dart Issue Comment on the same issue here dart-lang/sdk#33501 (comment)

[MiriDevAndro]

do you have find an solution ?

[lock]

This thread has been automatically locked since there has not been any recent activity after it was closed. If you are still experiencing a similar issue, please open a new bug, including the output of flutter doctor -v and a minimal reproduction of the issue.