cappuccino/Foundation/CPURLConnection.j

/*
 * CPURLConnection.j
 * Foundation
 *
 * Created by Francisco Tolmasky.
 * Copyright 2008, 280 North, Inc.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

@import "CPData.j"
@import "CPObject.j"
@import "CPRunLoop.j"
@import "CPURLRequest.j"
@import "CPURLResponse.j"

var CPURLConnectionDelegate = nil;

/*!
    @class CPURLConnection
    @ingroup foundation
    @brief Provides loading of a URL request.

    An interface to downloading content at a specified URL. Using one of the
    class methods, you can obtain the data.

    @delegate -(void)connection:(CPURLConnection)connection didFailWithError:(id)error;
    Called when the connection encounters an error.
    @param connection the connection that had an error
    @param error the error, which is either a javascript DOMException or an http
    status code (javascript number/CPNumber)

    @delegate -(void)connection:(CPURLConnection)connection didReceiveResponse:(CPHTTPURLResponse)response;
    Called when the connection receives a response.
    @param connection the connection that received a response
    @param response the received response

    @delegate -(void)connection:(CPURLConnection)connection didReceiveData:(CPString)data;
    Called when the connection has received data.
    @param connection the connection that received data
    @param data the received data

    @delegate -(void)connectionDidFinishLoading:(CPURLConnection)connection;
    Called when the URL has finished loading.
    @param connection the connection that finished loading

    Class Delegate Method:

    @delegate -(void)connectionDidReceiveAuthenticationChallenge:(id)connection
    The class delegate allows you to set global behavior for when authentication challenges (401 status codes) are returned.

    The recommended way to handle this method is to store a reference to the connection, and then use whatever
    method you have to authenticate yourself.  Once you've authenticated yourself, you should cancel
    and then start the connection:

<pre>
[connection cancel];
[connection start];
</pre>

    @param connection the connection that received the authentication challenge.
*/
@implementation CPURLConnection : CPObject
{
    CPURLRequest    _request;
    id              _delegate;
    BOOL            _isCanceled;
    BOOL            _isLocalFileConnection;

    BOOL            _withCredentials    @accessors(property=withCredentials);

    HTTPRequest     _HTTPRequest;
}

+ (void)setClassDelegate:(id)delegate
{
    CPURLConnectionDelegate = delegate;
}

/*
    Sends a request for the data from a URL. This is the easiest way to obtain data from a URL.
    @param aRequest contains the URL to request the data from
    @param aURLResponse not used
    @param anError not used
    @return the data at the URL or \c nil if there was an error
*/
+ (CPData)sendSynchronousRequest:(CPURLRequest)aRequest returningResponse:(/*{*/CPURLResponse/*}*/)aURLResponse
{
    var cfHTTPRequest = new CFHTTPRequest();

    return [CPURLConnection _sendSynchronousRequest:aRequest returningResponse:aURLResponse withCFHTTPRequest:cfHTTPRequest];
}

+ (CPData)sendSynchronousRequest:(CPURLRequest)aRequest returningResponse:(/*{*/CPURLResponse/*}*/)aURLResponse withCredentials:(BOOL)withCredentials
{
    var cfHTTPRequest = new CFHTTPRequest();

    cfHTTPRequest.setWithCredentials(withCredentials);

    return [CPURLConnection _sendSynchronousRequest:aRequest returningResponse:aURLResponse withCFHTTPRequest:cfHTTPRequest];
}

+ (CPData)_sendSynchronousRequest:(CPURLRequest)aRequest returningResponse:(/*{*/CPURLResponse/*}*/)aURLResponse withCFHTTPRequest:(CFHTTPRequest)aCFHTTPRequest
{
    try
    {
        aCFHTTPRequest.open([aRequest HTTPMethod], [[aRequest URL] absoluteString], NO);

        var fields = [aRequest allHTTPHeaderFields],
            key = nil,
            keys = [fields keyEnumerator];

        while ((key = [keys nextObject]) !== nil)
            aCFHTTPRequest.setRequestHeader(key, [fields objectForKey:key]);

        aCFHTTPRequest.send([aRequest HTTPBody]);

        if (!aCFHTTPRequest.success())
            return nil;

        return [CPData dataWithRawString:aCFHTTPRequest.responseText()];
    }
    catch (anException)
    {
    }

    return nil;
}

/*
    Creates a url connection with a delegate to monitor the request progress.
    @param aRequest contains the URL to obtain data from
    @param aDelegate will be sent messages related to the request progress
    @return a connection that can be \c started to initiate the request
*/
+ (CPURLConnection)connectionWithRequest:(CPURLRequest)aRequest delegate:(id)aDelegate
{
    return [[self alloc] initWithRequest:aRequest delegate:aDelegate];
}

//overloaded method that allows user to set _withCredentials
+ (CPURLConnection)connectionWithRequest:(CPURLRequest)aRequest delegate:(id)aDelegate withCredentials:(BOOL)withCredentials
{
    var connection = [[self alloc] initWithRequest:aRequest delegate:aDelegate startImmediately:NO];

    [connection setWithCredentials:withCredentials];
    [connection start];

    return connection;
}

/*
    Default class initializer. Use one of the class methods instead.
    @param aRequest contains the URL to contact
    @param aDelegate will receive progress messages
    @param shouldStartImmediately whether the \c -start method should be called from here
    @return the initialized url connection
*/
- (id)initWithRequest:(CPURLRequest)aRequest delegate:(id)aDelegate startImmediately:(BOOL)shouldStartImmediately
{
    self = [super init];

    if (self)
    {
        _request = aRequest;
        _delegate = aDelegate;
        _isCanceled = NO;
        _withCredentials = NO;

        var URL = [_request URL],
            scheme = [URL scheme];

        // Browsers use "file:", Titanium uses "app:"
        _isLocalFileConnection =    scheme === "file" ||
                                    ((scheme === "http" || scheme === "https") &&
                                     window.location &&
                                     (window.location.protocol === "file:" || window.location.protocol === "app:"));

        _HTTPRequest = new CFHTTPRequest();

        if (shouldStartImmediately)
            [self start];
    }

    return self;
}

- (id)initWithRequest:(CPURLRequest)aRequest delegate:(id)aDelegate
{
    return [self initWithRequest:aRequest delegate:aDelegate startImmediately:YES];
}

/*
    return the delegate
*/
- (id)delegate
{
    return _delegate;
}

/*
    Start the connection. Not needed if you used the class method +connectionWithRequest:delegate:
*/
- (void)start
{
    _isCanceled = NO;

    _HTTPRequest.setWithCredentials(_withCredentials);

    try
    {
        _HTTPRequest.open([_request HTTPMethod], [[_request URL] absoluteString], YES);

        _HTTPRequest.onreadystatechange = function() { [self _readyStateDidChange]; };

        var fields = [_request allHTTPHeaderFields],
            key = nil,
            keys = [fields keyEnumerator];

        while ((key = [keys nextObject]) !== nil)
            _HTTPRequest.setRequestHeader(key, [fields objectForKey:key]);

        _HTTPRequest.send([_request HTTPBody]);
    }
    catch (anException)
    {
        if ([_delegate respondsToSelector:@selector(connection:didFailWithError:)])
            [_delegate connection:self didFailWithError:anException];
    }
}

/*
    Cancels the current request.
*/
- (void)cancel
{
    _isCanceled = YES;

    try
    {
        _HTTPRequest.abort();
    }
    // We expect an exception in some browsers like FireFox.
    catch (anException)
    {
    }
}

- (BOOL)isLocalFileConnection
{
    return _isLocalFileConnection;
}

/* @ignore */
- (void)_readyStateDidChange
{
    if (_HTTPRequest.readyState() === CFHTTPRequest.CompleteState)
    {
        var statusCode = _HTTPRequest.status(),
            URL = [_request URL];

        if (statusCode === 401 && [CPURLConnectionDelegate respondsToSelector:@selector(connectionDidReceiveAuthenticationChallenge:)])
            [CPURLConnectionDelegate connectionDidReceiveAuthenticationChallenge:self];
        else
        {
            if ([_delegate respondsToSelector:@selector(connection:didReceiveResponse:)])
            {
                if (_isLocalFileConnection)
                    [_delegate connection:self didReceiveResponse:[[CPURLResponse alloc] initWithURL:URL]];
                else
                {
                    var response = [[CPHTTPURLResponse alloc] initWithURL:URL];
                    [response _setStatusCode:statusCode];
                    [response _setAllResponseHeaders:_HTTPRequest.getAllResponseHeaders()];
                    [_delegate connection:self didReceiveResponse:response];
                }
            }

            if (!_isCanceled)
            {
                if ([_delegate respondsToSelector:@selector(connection:didReceiveData:)])
                    [_delegate connection:self didReceiveData:_HTTPRequest.responseText()];
                if ([_delegate respondsToSelector:@selector(connectionDidFinishLoading:)])
                    [_delegate connectionDidFinishLoading:self];
            }
        }
    }

    [[CPRunLoop currentRunLoop] limitDateForMode:CPDefaultRunLoopMode];
}

/* @ignore */
- (HTTPRequest)_HTTPRequest
{
    return _HTTPRequest;
}

@end

@implementation CPURLConnection (Deprecated)

+ (CPData)sendSynchronousRequest:(CPURLRequest)aRequest returningResponse:(/*{*/CPURLResponse/*}*/)aURLResponse error:(id)anError
{
    _CPReportLenientDeprecation(self, _cmd, @selector(sendSynchronousRequest:returningResponse:));

    return [self sendSynchronousRequest:aRequest returningResponse:aURLResponse];
}

- (HTTPRequest)_XMLHTTPRequest
{
    _CPReportLenientDeprecation(self, _cmd, @selector(_HTTPRequest));

    return [self _HTTPRequest];
}

@end