How download file google drive api ios

Question

I tried to download file from google drive API since 3 day without success. I used this https://developers.google.com/drive/ios/devguide/files#reading_files.

But I can't understand what I need to put in *drive and *file?

I tried :
GTLDriveFile *file = @"fileText.txt"; (or I tried the url of my file on google drive...) The guide don't explain... And I didn't find real example.

GTLServiceDrive *drive = ...;
GTLDriveFile *file = ...;
NSString *url = [NSString stringWithFormat:@"https://www.googleapis.com/drive/v3/files/%@?alt=media",
                          file.identifier]
GTMSessionFetcher *fetcher = [drive.fetcherService fetcherWithURLString:url];

[fetcher beginFetchWithCompletionHandler:^(NSData *data, NSError *error) {
  if (error == nil) {
    NSLog(@"Retrieved file content");
    // Do something with data
  } else {
    NSLog(@"An error occurred: %@", error);
  }
}];

So I had search other code like but no one explain what I need to put in drive and file:

SOLUTION :

I had a problem of authorization with my scope, solved by total access to drive. I changed the scope (in quickstart code, look : "- (GTMOAuth2ViewControllerTouch *)createAuthController...") -->NSArray *scopes = [NSArray arrayWithObjects:kGTLAuthScopeDrive, nil];

For download (inspired by quickstart example) :

// self.service is my GTLServiceDrive

// When the view appears, ensure that the Drive API service is authorized, and perform API calls.
- (void)viewDidAppear:(BOOL)animated {
    if (!self.service.authorizer.canAuthorize) {
        // Not yet authorized, request authorization by pushing the login UI onto the UI stack.
        [self presentViewController:[self createAuthController] animated:YES completion:nil];
    } else {
        NSString *urltest = [NSString stringWithFormat:@"https://www.googleapis.com/drive/v3/files/%@?alt=media", identifier_file]; //the ID of my file in a string identifier_file
        GTMSessionFetcher *fetcher = [self.service.fetcherService fetcherWithURLString:urltest];  // the request
        // receive response and play it in web view:
        [fetcher beginFetchWithCompletionHandler:^(NSData *data, NSError *errorrr) {
            if (errorrr == nil) {
                NSLog(@"Retrieved file content");
                [webView_screen loadData:data MIMEType:@"application/pdf" textEncodingName:@"UTF-8" baseURL:nil]; //my file is a pdf
                [webView_screen reload];
            } else {
                NSLog(@"An error occurred: %@", errorrr);
            }
        }];
    }
}

If you want to save on the phone, you can look the Bala's code.

The problem is more, I have no idea what i need to put in *drive and *file: a identification? what type, what identification ? where can I find it? (it's the name of the file in the drive? but how this code can find the good file in the good folder in my google drive? (I don't understand the functionement of this protocol....) — G. Tommy

Bala Bala · Accepted Answer · 2016-05-02T06:05:34

First fetch the file from Drive

driveFiles = [[NSMutableArray alloc] init];
for (GTLDriveFile *file in files.items) {
    if ([file.mimeType isEqualToString:@"application/vnd.google-apps.folder"]) {

    } else {
        NSString *fileExtension = file.fileExtension;
        if (fileExtension) {
            if ([fileExtension isEqualToString:@"pdf"]) {
                [driveFiles addObject:file];
            }
        }
    }
}

And GTLDriveFile pass the object that you have in the array

GTLDriveFile *file=[driveFiles objectAtIndex:indexPath.row];

This is the code for download the file

NSString *link;
if (file.webContentLink) {
    link = file.webContentLink;
} else if (file.embedLink) {
    link = file.embedLink;
} else {
    UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"ERROR" message:@"File has no downloadable link" delegate:nil cancelButtonTitle:@"Ok" otherButtonTitles:nil, nil];
    [alert show];
}

if (link) {
    NSString *downloadUrl = file.downloadUrl;
    GTMHTTPFetcher *fetcher = [self.driveService.fetcherService fetcherWithURLString:downloadUrl];
    //async call to download the file data
    [fetcher beginFetchWithCompletionHandler:^(NSData *data, NSError *error) {
        if (error == nil) {
            if (data) {
                NSString *dirPath = [self directoryPathForSavingFile];
                NSString *filePath = [dirPath stringByAppendingPathComponent:file.title];
                [self saveFileJSONData:data forFileName:filePath withCompletionHandler:^(BOOL successStatus) {
                    // Adding skip attribute to avoid data sinking in iCloud
                    BOOL path = [[NSFileManager defaultManager] fileExistsAtPath:filePath];
                    if (path) {
                        NSLog(@"filePath %@", filePath);
                    }
                }];
            }
        } else {
            NSLog(@"An error occurred: %@", error);
        }
    }];
}

Code for Directory path for save the file

- (NSString *)directoryPathForSavingFile:(NSString *)directoryName {
    NSString *applicationDirectory = [NSHomeDirectory() stringByAppendingPathComponent:@"Documents"];
    applicationDirectory = [applicationDirectory stringByAppendingPathComponent:directoryName];
    return applicationDirectory;
}

How download file google drive api ios

1 Answers