CommunicationSingleton *CSS = [CommunicationSingleton sharedSingleton];

    // building the json object
    if (([emailString length] != 0) && ([passwordString length] != 0))
    {

        NSMutableURLRequest *request = [[NSMutableURLRequest alloc] init];
        NSString *requestURLString = [NSString stringWithFormat:@"%@authorize",[CSS getDefaultAPIURL]];
        [request setURL:[NSURL URLWithString:requestURLString]];
        [request setHTTPMethod:@"POST"];
        [request setValue:@"application/json" forHTTPHeaderField:@"Content-Type"];

        NSString *requestBodyString = [NSString stringWithFormat:@"{\"user_id\": \"%@\", \"password\": \"%@\", \"client_id\": \"%@\"}",emailString,passwordString,[[NSUserDefaults standardUserDefaults] objectForKey:@"ClientIdentificationForAuthorizationPurposes"]];
        [request setHTTPBody:[requestBodyString dataUsingEncoding:NSUTF8StringEncoding]];
        [request setTimeoutInterval:60];

        __block BOOL loginFailed = NO;

        __block BOOL invalidUser = NO;

        dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_HIGH, 0), ^(void){

            //build an info object and convert to json
            NSError *requestError;
            NSHTTPURLResponse *responseHTTP;

            NSData *response = [NSURLConnection sendSynchronousRequest:request returningResponse:&responseHTTP error:&requestError];

            if ([responseHTTP statusCode] == 200)
            {
                NSDictionary *tempdict = [NSJSONSerialization JSONObjectWithData:response options:NSJSONReadingMutableContainers error:&requestError];
                [CSS setUpAuthenticationForType:[tempdict valueForKey:@"token_type"] withID:[tempdict valueForKey:@"access_token"]];

                // authorization was successfull

            } else {

                loginFailed = YES;

                if (requestError.code == -1012) {

                    // Failed because it's an invalid user

                    invalidUser = YES;

                } else {

                    // check if project list stored on device.
                    // if yes, start offline mode
                }
            }
        });

    }

CommunicationSingleton *CSS = [CommunicationSingleton sharedSingleton];

    //build an info object and convert to json
    NSError *requestError;
    NSHTTPURLResponse *responseHTTP;

    NSMutableURLRequest *requestForSlug = [[NSMutableURLRequest alloc] init];

    NSString *teamRequestString = [NSString stringWithFormat:@"%@teams",[CSS getDefaultAPIURL]];
    [requestForSlug setURL:[NSURL URLWithString:teamRequestString]];
    [requestForSlug setHTTPMethod:@"GET"];
    [requestForSlug setValue:@"application/json" forHTTPHeaderField:@"Content-Type"];
    [requestForSlug setValue:[CSS getAuthorization] forHTTPHeaderField:@"Authorization"];

    NSData *responseForSlug = [NSURLConnection sendSynchronousRequest:requestForSlug returningResponse:&responseHTTP error:&requestError];
    [requestForSlug release];

    if ([responseHTTP statusCode] == 200) {
        // Success. Team names array.
        NSArray *tempdictForSlug = [NSJSONSerialization JSONObjectWithData:responseForSlug options:NSJSONReadingMutableContainers error:&requestError];
        NSLog(@"How many teams I am part of: %d", [tempdictForSlug count]);
    }else{
        // Login Failed.
    }

CommunicationSingleton *CSS = [CommunicationSingleton sharedSingleton];

    //build an info object and convert to json
    NSError *requestError;
    NSHTTPURLResponse *responseHTTP;

    //get projectList
    NSMutableURLRequest *requestForProjectList = [[NSMutableURLRequest alloc] init];

    NSString *projectListRequestString = [NSString stringWithFormat:@"%@%@/projects",[CSS getDefaultAPIURL],[CSS getSlug]];
    [requestForProjectList setURL:[NSURL URLWithString:projectListRequestString]];
    [requestForProjectList setHTTPMethod:@"GET"];
    [requestForProjectList setValue:@"application/json" forHTTPHeaderField:@"Content-Type"];
    [requestForProjectList setValue:[CSS getAuthorization] forHTTPHeaderField:@"Authorization"];

    NSData *responseForProjectList = [NSURLConnection sendSynchronousRequest:requestForProjectList returningResponse:&responseHTTP error:&requestError];

    [requestForProjectList release];

    if (responseForProjectList == NULL) {

            // Login Failed
    }
    else {

        NSError *error;
        NSArray *projectList = [NSJSONSerialization JSONObjectWithData:responseForProjectList options:NSJSONReadingMutableContainers error:&error];

        BOOL success = [[ProjectManager sharedProjectManager] loadProjectsFromData:projectList];

        if (!success){

            // Failed to Load Projects List

        }
    }

//build an info object and convert to json
        NSError *requestError;
        NSHTTPURLResponse *responseHTTP;
        NSError *dictError;

        //Get project details

        NSMutableURLRequest *requestForProjectDetails;
        requestForProjectDetails = [[NSMutableURLRequest alloc] init];

        [requestForProjectDetails setURL:[NSURL URLWithString:[NSString stringWithFormat:@"%@%@/projects/%@",[CSS getDefaultAPIURL],[CSS getSlug],proj.mID]]];
        [requestForProjectDetails setHTTPMethod:@"GET"];
        [requestForProjectDetails setValue:@"application/json" forHTTPHeaderField:@"Content-Type"];
        [requestForProjectDetails setValue:[CSS getAuthorization] forHTTPHeaderField:@"Authorization"];

        NSData *responseForProjectDetails = [NSURLConnection sendSynchronousRequest:requestForProjectDetails returningResponse:&responseHTTP error:&requestError];
        [requestForProjectDetails release];

        if (responseHTTP.statusCode == 200) {

            // Success, we have a project detail dictionary
            NSDictionary *projectDetails = [NSJSONSerialization JSONObjectWithData:responseForProjectDetails options:NULL error:&dictError];

            // Time to process this project details as you want/need
            [proj processProjectDetails:projectDetails];

        }else{
            // Download Failed
            return;
        }

//build an info object and convert to json
        NSError *requestError;
        NSHTTPURLResponse *responseHTTP;

        NSString* requestString = [[NSString alloc] initWithFormat:@"%@%@/projects/%@/topology",[CSS getDefaultAPIURL],[CSS getSlug], mProjectID];

        NSMutableURLRequest *requestForProjectsTree = [[NSMutableURLRequest alloc] init];
        [requestForProjectsTree setURL:[NSURL URLWithString:requestString]];
        [requestString release];

        [requestForProjectsTree setHTTPMethod:@"GET"];
        [requestForProjectsTree setValue:@"application/json" forHTTPHeaderField:@"Content-Type"];
        [requestForProjectsTree setValue:[[CommunicationSingleton sharedSingleton] getAuthorization] forHTTPHeaderField:@"Authorization"];

        NSData *response = [NSURLConnection sendSynchronousRequest:requestForProjectsTree returningResponse:&responseHTTP error:&requestError];
        [requestForProjectsTree release];

        NSString *path = [[proj getProjectFolderPath] stringByAppendingPathComponent:[NSString stringWithFormat:@"%@.topology", mProjectID]];

        if ([responseHTTP statusCode] == 200)
        {
            // Save project topology locally.
            [response writeToFile:path atomically:NO];

            // Load project topology to memory.
            [proj loadTopologyFromData:response];

        } else {

            // If Failed

            // Check if we have the last used topology for this project is available offline (rembember that this is could not be the last version)
            if ([[NSFileManager defaultManager] fileExistsAtPath:path]) {
                // Loading project topology offline

                NSData* data = [NSData dataWithContentsOfFile:path];
                [proj loadTopologyFromData:data];

            } else {
                // Download Failed + Local Storage not available
            }

        }

    Project* proj = [[ProjectManager sharedProjectManager] getProjectbyID:mProjectID];
    
    maxNodes = [[proj getAllNodesWithoutParents] count];
    
    // Don't download nodes data if we want to download them dynamically
    // we are still going to need the parents
    if ( ![[[NSUserDefaults standardUserDefaults] valueForKey:kDownloadNodesDynamically] boolValue] ) {
        
        dispatch_async(dispatch_get_main_queue(), ^(void){

            mDownloadManager = [[DownloadManager alloc] init];
            mDownloadManager.delegate = self;
            
            //get disciplines
            NSArray *disciplineIds = proj.projectsDisciplineIDs;
            for (int i = 0; i < [disciplineIds count]; i++) {
                [mDownloadManager downloadFiles:[proj getAllNodesWithoutParents] forProject:mProjectID forDiscipline:[disciplineIds objectAtIndex:i]];
            }
            
            if ([disciplineIds count] < 1) {
                [mDownloadManager downloadFiles:[proj getAllNodesWithoutParents] forProject:mProjectID forDiscipline:NULL];
            }
            
        });
    }

In "downloadFiles" method there are some logic and data storage operations and for each of the discipline you can call this snippet:


	NodeHeaderDatas *nodeDatas = [mFilesToProcess objectAtIndex:0];
	NSString *nodeidForAPICall = nodeDatas.nodeID;
    
	CommunicationSingleton *CSS = [CommunicationSingleton sharedSingleton];
	NSMutableURLRequest *requestForNodeData = [[NSMutableURLRequest alloc] init];
	NSString *nodesURL;
        if (nodeDatas.disciplineForDownloading != NULL) {
            nodesURL = [NSString stringWithFormat:
                        @"%@%@/objects/%@/disciplines/%@/geometries/threejs",
                        [CSS getDefaultAPIURL],
                        [CSS getSlug],
                        nodeidForAPICall,
                        nodeDatas.disciplineForDownloading];
        }else{
            nodesURL = [NSString stringWithFormat:
                        @"%@%@/objects/%@/geometries/threejs",
                        [CSS getDefaultAPIURL],
                        [CSS getSlug],
                        nodeidForAPICall];
            
        }
        [requestForNodeData setURL:[NSURL URLWithString:nodesURL]];
        [requestForNodeData setHTTPMethod:@"GET"];
        [requestForNodeData setValue:@"application/json" forHTTPHeaderField:@"Content-Type"];
        [requestForNodeData setValue:[CSS getAuthorization] forHTTPHeaderField:@"Authorization"];
        
        if(requestForNodeData){
            mConnection = [[NSURLConnection alloc] initWithRequest:requestForNodeData delegate:self startImmediately:YES];
        }
if (!mConnection)
        {
            // Connection Failed
        }
        else
        {
            [mConnection scheduleInRunLoop:[NSRunLoop currentRunLoop] forMode:NSRunLoopCommonModes];
            [mConnection start];
        }
        [requestForNodeData release];