Uploading image and text values to server - ios

Question

I'm trying to create a new object with an image and some other values using multipart but I can't get it to work.
This is the code I was using without uploading an image (this works):
let request = NSMutableURLRequest(URL: NSURL(string: self.submitLink)!)
let session = NSURLSession.sharedSession()
let params = [
"article": [
"name" : name,
"description" : fullDescription.text!,
"subdescription" : sDescription,
"category_id" : categoriesArray[self.categoryPicked]["id"] as! Int,
"location_id" : locationsArray[self.locationPicked]["id"] as! Int,
"Xcoordinate" : self.lat,
"Ycoordinate" : self.lng,
"user_id" : User.sharedInstance.userId,
"article_images_attributes[][image]" : ""
]
]
request.HTTPBody = try? NSJSONSerialization.dataWithJSONObject(params, options: NSJSONWritingOptions())
request.addValue("application/json", forHTTPHeaderField: "Content-Type")
request.addValue("application/json", forHTTPHeaderField: "Accept")
request.HTTPMethod = "POST"
let task = session.dataTaskWithRequest(request, completionHandler: { data, response, error -> Void in
print("article created.")
})
task.resume()
and this is the code I'm using at the moment (not working):
let params = [
"article[name]" : name,
"article[description]" : fullDescription.text!,
"article[subdescription]" : sDescription,
"article[category_id]" : categoriesArray[self.categoryPicked]["id"] as! Int,
"article[location_id]" : locationsArray[self.locationPicked]["id"] as! Int,
"article[Xcoordinate]" : self.lat,
"article[Ycoordinate]" : self.lng,
"article[user_id]" : User.sharedInstance.userId
]
let boundaryConstant = "----------V2ymHFg03ehbqgZCaKO6jy"
let fileParamConstant = "article[article_images_attributes][][image]"
let session = NSURLSession.sharedSession()
let request = NSMutableURLRequest(URL: NSURL(string: self.submitLink)!)
request.HTTPMethod = "POST"
let contentType = "multipart/form-data; boundary=\(boundaryConstant)"
request.setValue(contentType, forHTTPHeaderField: "Content-Type")
let body = NSMutableData()
for param in params {
print(param)
body.appendData("--\(boundaryConstant)\r\n".dataUsingEncoding(NSUTF8StringEncoding)!)
body.appendData("Content-Disposition: form-data; \(param.key)=\r\n\r\n".dataUsingEncoding(NSUTF8StringEncoding)!)
body.appendData("\(param.value)\r\n".dataUsingEncoding(NSUTF8StringEncoding)!)
}
let imageData = UIImageJPEGRepresentation(self.photoArray[0], 1)
if imageData != nil {
body.appendData("--\(boundaryConstant)\r\n".dataUsingEncoding(NSUTF8StringEncoding)!)
body.appendData("Content-Disposition: form-data; name=\(fileParamConstant); filename=\"image.jpg\"\r\n".dataUsingEncoding(NSUTF8StringEncoding)!)
body.appendData("Content-Type: application/octet-stream\r\n\r\n".dataUsingEncoding(NSUTF8StringEncoding)!)
body.appendData(imageData!)
body.appendData("\r\n".dataUsingEncoding(NSUTF8StringEncoding)!)
}
body.appendData("--\(boundaryConstant)\r\n".dataUsingEncoding(NSUTF8StringEncoding)!)
request.HTTPBody = body
let task = session.dataTaskWithRequest(request, completionHandler: { data, response, error -> Void in
print(request)
print(data)
})
task.resume()
Whenever I try to submit my form the server replies with:
NoMethodError (undefined method `name' for nil:NilClass)
So I assume there is something wrong with the way I defined my params? Could someone explain it to me a bit more in-depth so I know what I did wrong?

Answer 1

It looks like you are using the wrong Content-Type for your image and the name may not be correct.
Try something like this to set up your image:
NSMutableData *body = [NSMutableData data];
double compressionRatio=0.7;
NSData* imageData = UIImageJPEGRepresentation((UIImage*)dataParam, compressionRatio);
[self utfAppendBody:body data:[NSString stringWithFormat:#"Content-Disposition: form-data; name=\"%#\"; filename=\".jpg\"\r\n", paramName]];
[self utfAppendBody:body data:#"Content-Type: image/jpeg\r\n\r\n"];
[body appendData:imageData];
With this helper function:
- (void)utfAppendBody:(NSMutableData *)body data:(NSString *)data {
[body appendData:[data dataUsingEncoding:NSUTF8StringEncoding]];
}