Need a way to add HTTP Headers

[conanoc]

I need a way to add custom HTTP headers to parse http requests.
Parse android SDK has an API to add "network interceptors" which can modify request object (or response object either).

It will be good if I can add or remove headers at any point before making requests. I can only set network interceptors at initialization time on android SDK.

[nlutsenko]

This sounds like a good feature request.
Network interceptors sounds like a little bit of overkill, because at that point you might as well fork the SDK and add that functionality.

In terms of headers, let me ask you few questions:

• Would you set the http headers once at the initialization time of the SDK or per every request is a requirement?
• What is your use case for the headers? Purely so we can understand it better and maybe extend more portions that just this, or suggest an alternative solution...

[conanoc]

Okay. Let me add some information.
I need additional http headers for authentication. The parse server will be placed inside of a kind of gateway and that gateway requires some headers.

The required headers are dependent to the user, so the headers could be changed. Not have to be changed per every request but can be changed at some point after the initialization time.

[nlutsenko]

This is challenging, though we probably can find a way to make this work.
You can definitely get this working using OSS fork of the SDK and exposing/changing PFURLSessionCommandRunner. Let me know if that solution works for you.

[conanoc]

Yes. If the commandRunner instance is accessible and it provides an API to set headers, it will be enough.

[nlutsenko]

Would a fork work in your case then?

[conanoc]

I'm not sure how to get the instance of PFURLSessionCommandRunner.

[conanoc]

I found a way to get the instance of PFURLSessionCommandRunner.

commandRunner = [[ParseManager currentParseManager_] commandRunner];

But that commandRunner is a singleton and has fixed headers already set. So I will not be able to change the headers later.

I think the following way might be possible.

1. add a setter in PFCommandURLRequestConstructor to set additional headers.
2. change _getURLRequestHeadersAsyncForCommand: to include the headers.

I think I could get the PFCommandURLRequestConstructor by [commandRunner __requestConstructor]
@nlutsenko what do you think? I hope It can be done without fork.

[janajri]

Bump, @conanoc were you able to find a work around for this?

[jcnm]

This could be paired/a response to the parse-server's issue #1059 ?

[conanoc]

@jakeblakeley not yet.

[conanoc]

I end up use swizzling as an adhoc way.
It seems to work well and I could add headers without fork. Lynk and LynkRequestConstructor are classes in my app.

@implementation LynkRequestConstructor

///--------------------------------------
#pragma mark - Public
///--------------------------------------

+ (NSMutableURLRequest *)urlRequestWithURL:(NSURL *)url
                                httpMethod:(NSString *)httpMethod
                               httpHeaders:(NSDictionary *)httpHeaders
                                parameters:(NSDictionary *)parameters {
    NSDictionary *additionalHeaders = [[Lynk sharedInstance] neoidHeaders];
    NSMutableDictionary *headers = [NSMutableDictionary dictionaryWithDictionary:httpHeaders];
    [headers addEntriesFromDictionary:additionalHeaders];

    return [LynkRequestConstructor urlRequestWithURL:url httpMethod:httpMethod httpHeaders:headers parameters:parameters];
}

+ (void) swizzleMethod {
    SEL selector = @selector(urlRequestWithURL:httpMethod:httpHeaders:parameters:);
    Method originalMethod = class_getClassMethod(NSClassFromString(@"PFHTTPURLRequestConstructor") , selector);
    Method swizzledMethod = class_getClassMethod([self class] , selector);
    method_exchangeImplementations(originalMethod, swizzledMethod);
}

@end

[seejayuu]

I am trying to get Gzip working for all parse requests. I enabled and tested compression on my heroku-hosted Parse instance and all is good. However, my iOS app isn't setting Accept Encoding: Gzip. Am I doing something stupid or is this another instance where custom headers would help?

[richardjrossiii]

@seejayuu I remember testing this a long time ago (GZIP is enabled on all Parse.com responses over 1KB IIRC), and it seemed like NSURLConnection which we were using at the time automatically inserted that header.

It's possible that NSURLSession no longer shares that behavior, which would be quite odd, and a separate bug in its own regard.

[conanoc]

@seejayuu NSURLSession also sends Accept Encoding: Gzip header by defaults. You don't have to do anything to enable gzip in your ios app. You could see your packets gzipped if you capture them by packet sniffers.