Read the REST Response Body in Chunks

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Demonstrates Rest.ReadRespChunkBd, which reads the response body one chunk at a time, appending each chunk to a BinData. A return value of 0 signals the body is complete, while -1 indicates a read failure.

#import <CkoRest.h>
#import <CkoStringBuilder.h>
#import <CkoBinData.h>

BOOL success = NO;

CkoRest *rest = [[CkoRest alloc] init];
BOOL bTls = YES;
BOOL bAutoReconnect = YES;
success = [rest Connect: @"example.com" port: [NSNumber numberWithInt: 443] tls: bTls autoReconnect: bAutoReconnect];
if (success == NO) {
    NSLog(@"%@",rest.LastErrorText);
    return;
}

success = [rest SendReqNoBody: @"GET" uriPath: @"/api/largefile"];
if (success == NO) {
    NSLog(@"%@",rest.LastErrorText);
    return;
}

int statusCode = [[rest ReadResponseHeader] intValue];
if (statusCode < 0) {
    NSLog(@"%@",rest.LastErrorText);
    return;
}

//  Check for the expected success status code.  If the response is not 200, the body is likely
//  error text formatted as JSON, XML, or HTML rather than the expected content.  In that case read
//  the body as text, report it, and return.
if (statusCode != 200) {
    CkoStringBuilder *sbError = [[CkoStringBuilder alloc] init];
    success = [rest ReadRespSb: sbError];
    if (success == NO) {
        NSLog(@"%@",rest.LastErrorText);
        return;
    }

    NSLog(@"%@%d",@"Request failed with status code ",statusCode);
    NSLog(@"%@",[sbError GetAsString]);
    return;
}

//  The status code is 200.  Read the response body in chunks, appending each chunk to the BinData.
//  Each call waits until at least the requested number of bytes is available, unless the response
//  ends first.  A return value of 0 means the final bytes were returned and the body is complete;
//  -1 indicates a read failure.
CkoBinData *bdBody = [[CkoBinData alloc] init];
int chunkResult = [[rest ReadRespChunkBd: [NSNumber numberWithInt: 8192] bd: bdBody] intValue];
while (chunkResult > 0) {
    chunkResult = [[rest ReadRespChunkBd: [NSNumber numberWithInt: 8192] bd: bdBody] intValue];
}

if (chunkResult < 0) {
    NSLog(@"%@",rest.LastErrorText);
    return;
}

NSLog(@"%@%d%@",@"Received ",[bdBody.NumBytes intValue],@" bytes.");