Question

I am looking to upload a photo from iPhone to a 4D Server. Specifically to upload a photo taken on an iPhone, uploaded to a 4D Server and stored as a JPEG image in the WebFolder. I am using 4D Server version 12 and 13. I have looked at other postings here but I cannot make any of them apply to 4D. Anyone know how to do this?

Answer 1

It took me a while but I finally puzzled together the various procedures to make this work. Thumbs up to the iriphon blog (http://www.iriphon.com/2011/11/09/ios-uploading-an-image-from-your-iphone-to-a-server/) for putting me on the right track.

Here is the iOS code I used:

-(IBAction)uploadPhoto:(id)sender {
NSMutableURLRequest *request = [[NSMutableURLRequest alloc] initWithURL:[NSURL URLWithString:@"http://www.domain.com/4DACTION/showcaseUploadPic"]
                                                            cachePolicy:NSURLRequestUseProtocolCachePolicy
                                                        timeoutInterval:60]; 

[request setHTTPMethod:@"POST"]; 

// We need to add a header field named Content-Type with a value that tells that it's a form and also add a boundary.
// I just picked a boundary by using one from a previous trace, you can just copy/paste from the traces.
NSString *boundary = @"----WebKitFormBoundaryQkZe6RUJZ2xbzXLB";

NSString *contentType = [NSString stringWithFormat:@"multipart/form-data; boundary=%@",boundary];

[request addValue:contentType forHTTPHeaderField: @"Content-Type"];
// end of what we've added to the header.

// the body of the post.
NSMutableData *body = [NSMutableData data];

// Now we need to append the different data 'segments'. We first start by adding the boundary.
[body appendData:[[NSString stringWithFormat:@"\r\n--%@\r\n",boundary] dataUsingEncoding:NSUTF8StringEncoding]];

// Now append the image
// Note that the name of the form field is exactly the same as in the trace ('picBLOB' in my case).
// You can choose whatever filename you want.
[body appendData:[[NSString stringWithString:@"Content-Disposition: form-data; name=\"picBLOB\" filename=\"image001.jpg\"\r\n"] dataUsingEncoding:NSUTF8StringEncoding]];

// We now need to tell the receiver what content type we have.
// In my case it's a jpg image. If you have a png, set it to 'image/png'.
[body appendData:[[NSString stringWithString:@"Content-Type: image/jpg\r\n\r\n"] dataUsingEncoding:NSUTF8StringEncoding]];

// Now we append the actual image data.
// I use a NSData object called photoData.
[body appendData:[NSData dataWithData:photoData]];

NSLog(@"photoData size = %i",[photoData length]);

// and again the delimiting boundary.
[body appendData:[[NSString stringWithFormat:@"\r\n--%@--\r\n",boundary] dataUsingEncoding:NSUTF8StringEncoding]];

// adding the body we've created to the request.
[request setHTTPBody:body];

NSURLConnection * connection = [[NSURLConnection alloc] initWithRequest:request delegate:self];
NSLog(@"connection = %@",connection);
}

Don’t forget to include the NSURLConnection delegates!

I used Wireshark, as described in the blog, to get the exact data I needed. I am using NSData to store the photo I had just taken with the camera and want to upload. Because of this my code is slightly different than if you wanted to upload a stored file.

Here is the 4D (version 12) code:

$ba:=BLOB size(picBLOB)
C_PICTURE(imageVar)
If (Undefined(picBLOB))  // in case user tries to reload /4DACTION/WEB_Set_Limits
C_BLOB(picBLOB)
End if 

If (BLOB size(picBLOB)>0)  // did user select a file for uploading?
C_STRING(255;$fileHeader)
$offset:=0  // BLOB to text requires a variable for the offset parameter
$fileHeader:=BLOB to text(picBLOB;Mac text without length;$offset;255)
$fileNameBegin:=Position("filename=";$fileHeader)+10
For ($i;$fileNameBegin;255)
If ($fileHeader≤$i≥=Char(Double quote))
$fileNameEnd:=$i
$i:=255
End if 
End for 
$fileName:=Substring($fileHeader;$fileNameBegin;$fileNameEnd-$fileNameBegin)
$contentTypeBegin:=Position("Content-Type:";$fileHeader)+14
For ($i;$contentTypeBegin;255)
If ($fileHeader≤$i≥=Char(Carriage return))
$contentTypeEnd:=$i
$i:=255
End if 
End for 
contentType:=Substring($fileHeader;$contentTypeBegin;$contentTypeEnd-$contentTypeBegin)
DELETE FROM BLOB(picBLOB;0;$contentTypeEnd+3)

BLOB TO PICTURE(picBLOB;imageVar;"JPEG")
$FILENAME:=":WebFolder:myPhoto.jpg"
WRITE PICTURE FILE($FILENAME;imageVar;"JPEG")

End if 

Here is the 4D (version 13) code:

C_BLOB(picBLOB)
C_PICTURE(imageVar)

WEB GET BODY PART(1;picBLOB;myPhoto)

If (BLOB size(picBLOB)>0)
BLOB TO PICTURE(picBLOB;imageVar;"JPEG")
$FILENAME:=":WebFolder:myPhoto.jpg"
WRITE PICTURE FILE($FILENAME;imageVar;"JPEG")
End if