Writing to Google Sheets without authentication

Question

In one of my projects I need to write data from an app (iOS and Android) to a Google Sheet document. I need to write the data to a spreadsheet that is not belonged to the user, the spread sheet is under my company account.

According to the docs, for this type of scenario I can use Create credentials > API key to set up a none-authentication key.
My concerns are that anyone could fetch this key within the app (using some basic reverse-engineering methods). I had an idea to create a user with write only credentials and using his API-KEY to preform the API requests. But i'm sure there is a better way to achieve this.

What are my options? Thank you so much!

Answer 1

you can use google app scripts to depoly a webapp that can be accessed by anyone even anonymous and then create an Async method in your app that runs that script. an example of such a webapp can be seen here: https://gist.github.com/petyr47/7af08ec2d982399c1b4ace2734597d3b.js then you can add an AsyncTask method that looks like this :

public class SendRequest extends AsyncTask<String, Void, String> {


        protected void onPreExecute(){}

        protected String doInBackground(String... arg0) {

            try{

                //Enter script URL Here
                URL url = new URL("Your App Script Web App URL");

                JSONObject postDataParams = new JSONObject();

                //Passing scanned code as parameter

               postDataParams.put("sdata",scannedData);


                Log.e("params",postDataParams.toString());

                HttpURLConnection conn = (HttpURLConnection) url.openConnection();
            conn.setReadTimeout(15000 /* milliseconds */);
            conn.setConnectTimeout(15000 /* milliseconds */);
            conn.setRequestMethod("GET");
            conn.setDoInput(true);
            conn.setDoOutput(true);

            OutputStream os = conn.getOutputStream();
            BufferedWriter writer = new BufferedWriter(
                    new OutputStreamWriter(os, "UTF-8"));
            writer.write(getPostDataString(postDataParams));

            writer.flush();
            writer.close();
            os.close();

            int responseCode=conn.getResponseCode();

            if (responseCode == HttpsURLConnection.HTTP_OK) {

                BufferedReader in=new BufferedReader(new InputStreamReader(conn.getInputStream()));
                StringBuffer sb = new StringBuffer("");
                String line="";

                while((line = in.readLine()) != null) {

                    sb.append(line);
                    break;
                }

                in.close();
                return sb.toString();

            }
            else {
                return new String("false : "+responseCode);
            }
        }
        catch(Exception e){
            return new String("Exception: " + e.getMessage());
        }
    }

    @Override
    protected void onPostExecute(String result) {
        Toast.makeText(getApplicationContext(), result,
                Toast.LENGTH_LONG).show();

    }
}

public String getPostDataString(JSONObject params) throws Exception {

    StringBuilder result = new StringBuilder();
    boolean first = true;

    Iterator<String> itr = params.keys();

    while(itr.hasNext()){

        String key= itr.next();
        Object value = params.get(key);

        if (first)
            first = false;
        else
            result.append("&");

        result.append(URLEncoder.encode(key, "UTF-8"));
        result.append("=");
        result.append(URLEncoder.encode(value.toString(), "UTF-8"));

    }
    return result.toString();
}

}

you can execute this method with:

 new SendRequest().execute();

replace the parameters in the method with what you would like to send. hope this helps

this is a solution for android though, i can't help with iOS but you can apply the same principle.