Hi i have been learning rails for a bit , now i need to make some mobile applications android & IOS connecting to my webapp, I know that the API is used to make the connections like the endpoints / url and then the methods for each and everyone of them is used to make it, my problem how can i know or test that my API for the mobile is working properly?
I am currently doing the android par and i don't know where to start with that. can guys also help with pointing out where to learn them, i mean creating user's in my webapp , I used device so i need to make an android application to make user's , insert data into my PG(postgresql) , get some geolocaion (geocoder), from the webapp , but i don't know where to start with the android how to send and get data from that, also how to test if the API that i made is working properly....
any help willbe greatly appreciated specially links to tutorials for rails version 4.+
I'm showing you the simplest way to do this things.
First make a json formatted api using rails. And you can make a URL that can accept GET method value(www.exmp.com?val=asd).
In your android application make a Class name JsonParser.
copy and paste the following code.
private String jsonurl;
public JsonParser(String url) {
this.jsonurl = url;
}
public String fetchJSON(){
try {
URL url = new URL(jsonurl);
HttpURLConnection conn = (HttpURLConnection) url.openConnection();
conn.setReadTimeout(15000);
conn.setConnectTimeout(25000);
conn.setRequestMethod("GET");
conn.setDoInput(true);
conn.connect();
InputStream stream = conn.getInputStream();
String data = convertStreamToString(stream);
return data;
} catch (Exception e) {
Log.d("Check", e.getMessage());
return null;
}
}
private String convertStreamToString(java.io.InputStream is) {
java.util.Scanner s = new java.util.Scanner(is).useDelimiter("\\A");
return s.hasNext() ? s.next() : "";
}
After that make a Object of that class in a Asynctask thread. and also give the URL as a parameter.you will get the Json formatted data.
To get the actual data you need to make a JSONObject type object and call like this .
JSONObject reader = new JSONObject(jsonData); // returning json formatted data
this.status = reader.getString("status");
Now you can make java Bean to get or set the value for further uses.
Related
I am trying to develop a part of my app in which i want to get video details for a keyword. I am using the search list API. I think I have an issue with the authorization. I am getting a 401. I have tried passing my authorization details.
I have tried the following code after going through a few resources online and I am current getting the java.io.FileNotFoundException at the line at which i get the Input Stream. The connection code that I am getting is a 401.
The given code is in the doInBackground of an AsyncTask.
String ytres="";
URL url;
HttpURLConnection urlConnection = null;
try {
Log.d("youtubedata","a1");
url = new URL("https://www.googleapis.com/youtube/v3/search?part=id&q=queen%20bohemian");
Log.d("youtubedata","a2");
Log.d("youtubedata","a");
urlConnection = (HttpURLConnection) url
.openConnection();
urlConnection.setRequestMethod("GET");
urlConnection.setRequestProperty ("Authorization", "Bearer MYAPIKEY");
urlConnection.setRequestProperty ("Accept", "application/json");
Log.d("youtubedatanum",Integer.toString(urlConnection.getResponseCode()));
InputStream in = urlConnection.getInputStream();
InputStreamReader isw = new InputStreamReader(in);
int data = isw.read();
while (data != -1) {
char current = (char) data;
data = isw.read();
ytres=ytres+current;
System.out.print(current);
}
Log.d("youtubedata",ytres);
} catch (Exception e) {
e.printStackTrace();
} finally {
if (urlConnection != null) {
urlConnection.disconnect();
}
}
return ytres;
I do suspect the issue is in the way i have passed my API Key.
Please go through the API docs at Calling the API and at Search Endpoint.
You'll see that your URL does not contain the needed API key passed on as the key parameter.
It may also worth it to dug up Google's own sample Java implementation at Search.java. However, that code, due to the layer of library abstraction it uses, is not of immediate help since it obscures the way a client should work directly with the API.
For You-tube Data API error 401
Possible issue for unauthorized (401) can be
authorizationRequired
youtubeSignupRequired
Check You-tube Data API error doc Here.
Also confirm that you have follow THIS steps to integrate API.
Sample API Code you can find Here
Hope this can help you.
I'm facing a problem in my app Android that consists in a failure to recover large json data from web service. The JSON data is large because contains images which are recovered from a table in my database.
Some days ago everything was working fine, but the number of registers in this table grew up fastly and then the problem rises.
This problem is not happening on iOS or on Android emulator, just on real Android device.
The code is stopping the download suddenly and throwing the error
org.json.JSONException: Unterminated string at character <cccc> of <json data>
That is, the code is not downloading the entire JSON data. Besides, the download stops in a different point always I run the code.
Someone know why that is happening?
This is the function which tries to recover the data from web service:
protected static JSONObject executeJSONQuery(ContentValues values,
WebServiceResolverCode code, Context context)
throws ContratoInativoException, JSONException {
URL url;
HttpURLConnection conn;
JSONObject jArray = null;
// build the string to store the response text from the server
String response = "";
try {
url = new URL(WebServiceResolver.getWebServiceSufix(code, context));
String param = "";
for (String key : values.keySet()) {
Object value = values.get(key);
param += key+"="+ URLEncoder.encode(value!=null?values.getAsString(key):"", "UTF-8")+"&";
}
conn = (HttpURLConnection) url.openConnection();
conn.setDoOutput(true);
conn.setRequestMethod("POST");
conn.setFixedLengthStreamingMode(param.getBytes().length);
conn.setRequestProperty("Content-Type", "application/x-www-form-urlencoded");
// send the POST out
OutputStreamWriter out = new OutputStreamWriter(conn.getOutputStream());
out.write(param);
out.flush();
out.close();
// start listening to the stream
Scanner inStream = new Scanner(conn.getInputStream());
while (inStream.hasNextLine()){
response += (inStream.nextLine());
}
inStream.close();
// process the stream and store it in StringBuilder
jArray = new JSONObject(response);
} catch (IOException ex) {
ex.printStackTrace();
Log.d("ERROR JSON STRING", response);
}
return jArray;
}
Firstly, do not keep an image in a table. Keep it in your server space and keep the URL to the image in your table. When you need to load the image, load it with the URL kept in the table.
Secondly, JSON is a light weight data interchange format. You should limit the number of items it carries. Its advisable not to let it carry up to a hundred rows in your table(when converting to JSON). If you have to, then load a little at first, then load another little, till it gets to the end. That's the idea behind infinite scrolling.
That way, it loads your data efficiently.
Looks like your json string object is not forming correctly. It may be missing s double quote at the end of a string. Check the param string object.
I am trying to get list of videos uploaded on my YouTube channel using following
https://www.googleapis.com/youtube/v3/search?part=snippet&channelId{MY_CHANNEL_ID}&maxResults=50&key={MY_APP_ID}
I have created App in Google App Console and generate APP ID for the same. But when I trying to access it through my Android application getting java.io.FileNotFoundException error
I have given application identifier and SHA1 also, If I try to access through Web Browser key without any other constrains it works well and returns all the video list but in case of Android it is not working.
#Override
protected String doInBackground(Void... voids) {
HttpURLConnection urlConnection = null;
String urlString = "https://www.googleapis.com/youtube/v3/search?part=snippet&channelId=UCrF362wkcVnjqqPRsSEzvgg&maxResults=50&key=AIzaSyAiAFjZb1eVdRxVWnymrhuAb1iDlmYupu8";
//urlString = "https://www.googleapis.com/youtube/v3/playlistItems?part=snippet&playlistId=PLTqSMwQKOhUhl7gm7h6YwX6XPYr0ViBtu&key=AIzaSyAiAFjZb1eVdRxVWnymrhuAb1iDlmYupu8";
String jsonString = new String();
URL url = null;
try {
url = new URL(urlString);
urlConnection = (HttpURLConnection) url.openConnection();
urlConnection.setRequestMethod("GET");
urlConnection.setReadTimeout(10000 /* milliseconds */);
urlConnection.setConnectTimeout(15000 /* milliseconds */);
urlConnection.setDoOutput(true);
urlConnection.connect();
BufferedReader br=new BufferedReader(new InputStreamReader(url.openStream()));
char[] buffer = new char[1024];
StringBuilder sb = new StringBuilder();
String line;
while ((line = br.readLine()) != null) {
sb.append(line+"\n");
}
br.close();
jsonString = sb.toString();
System.out.println("JSON: " + jsonString);
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (ProtocolException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return jsonString;
}
Error Log
BasicNetwork.performRequest: Unexpected response code 403 for https://www.googleapis.com/youtube/v3/search?part=snippet&channelId=UCrF362wkcVnjqqPRsSEzvgg&maxResults=50&key=AIzaSyAiAFjZb1eVdRxVWnymrhuAb1iDlmYupu8
05-13 15:28:26.607 19118-19151/com.jeevanmulmantra W/System.err: java.io.FileNotFoundException: https://www.googleapis.com/youtube/v3/search?part=snippet&channelId=UCrF362wkcVnjqqPRsSEzvgg&maxResults=50&key=AIzaSyAiAFjZb1eVdRxVWnymrhuAb1iDlmYupu8
Without looking at your API Console settings, I cannot say for sure. But from looking at the HTTP response, it looks like your IP address might be blocked by the Google authorization server. Hence, it is sending you back an unauthorized request HTTP status code 403.
Go to your API Console and select the None radio button from under the Key restrictions section. Then try again. It should work.
This is not exactly what you are asking but I will share my experience.
I had a similar situation a couple of months ago. Seaching on line I got to the conclusion that the YouTube api option for Android just doesn't work. I ended up with a more convenient solution for my development:
I got a YT api key for a website and bound it to the corresponding domain.
I Created a php file that gets the playlist from youtube twice a day using curl and cron job setup on the server. The playlist file in json format is then written to the web server (refreshed twice a day).
The Android app connects to my server intead of YTs and get the "cached" json play list from there.
This option drastically reduces the impact on the quota consumption because all the hits to the playlist go to the website.
If you are interested in this option I can share the php used for getting the play list.
I had the same problem, just regenerate another key and restrict it again with the package name and SHA1 from your Android Studio. It wasn't working with the old key regenerating the key and restricting it again worked for me.
I followed this to Parse Json In Android
I have Successfully Done it with HttpData handler..
Here I am Successfully Posting Data to server and Getting Response..
Now I want to Use this same in the Part of HTTPS..
Can Any one suggest me How to do this Without Major Changes in my code.. Because In my application I am doing this for more activities.. Please Suggest me to Use HTTPs in my code..
I will provide Additional Info... Depending Responses...
Update
In my code I have Changed HttpURLConnection to HttpsURLConnection
Please suggest me How to through this error In my code..
Update 1
I have Changed Certificate on server side.. Now its working On Https..
But Now,
I want to Use HTTP and HTTPS Both in one app Depending on Client Requirement So here now its worked with Https....
But I also need to work with Http
In my Code Can any any one suggest me...I want I should Work with Https and Http Both In one App.
to use both HTTP and HTTPS, you need to have the 2 methods (i think you already have them)
GetHTTPData(String urlString)
GetHTTPSData(String urlString)
now in HTTPDataHandler class (where you have both methods above)
you need to create a 3rd method GetDataFromUrl(), that will check URL and decide which method to use (http or https)
public String GetDataFromUrl(String url){
if(url.toLowerCase().startsWith("https")){
//HTTPS:
return GetHTTPSData(url);
}else{
//HTTP:
return GetHTTPData(url);
}
}
now in the AsyncTask class ProcessJSON
replace this line stream = hh.GetHTTPData(urlString);
with this one stream = hh.GetDataFromUrl(urlString);
if you don't want to add that 3rd method in HTTPDataHandler, just use the if-statement in ProcessJSON at doInBackground() to call either one of the 2 methods (http or https)
You can use HttpsURLConnection, replace HttpURLConnection by HttpsURLConnection .
public String GetHTTPData(String urlString){
try{
URL url = new URL(urlString);
HttpsURLConnection urlConnection =(HttpsURLConnection)url.openConnection();
// Check the connection status
if(urlConnection.getResponseCode() == 200)
{
// if response code = 200 ok
InputStream in = new BufferedInputStream(urlConnection.getInputStream());
// Read the BufferedInputStream
BufferedReader r = new BufferedReader(new InputStreamReader(in));
StringBuilder sb = new StringBuilder();
String line;
while ((line = r.readLine()) != null) {
sb.append(line);
}
stream = sb.toString();
// End reading...............
// Disconnect the HttpURLConnection
urlConnection.disconnect();
}
else
{
// Do something
}
}catch (MalformedURLException e){
e.printStackTrace();
}catch(IOException e){
e.printStackTrace();
}finally {
}
// Return the data from specified url
return stream;
}
What I understand is in your server side, they used self signed SSL certificate. So you have to install that certificate in your android device also. Settings > Security > install form storage.But for production build you have to buy ssl certificate from CA Authorities.
Hope this will solve your problem.
Remove HttpDataHandler lines in doInBackground use HttpUrlConnection directly in doInBackground or use HttpUrlConnection in JSONparse class to post params to server follow this tutorial to post params Website
I need to send a JSON request similar to jQuery's ajax method.
The official documentation quote on the data parameter says:
If value is an Array, jQuery serializes multiple values with same key based on the value of the traditional setting
So I have the same situation - a key that maps to an array "parameters":[123123, {"category":"123"}]
The complete data parameter looks like
$.ajax({
url: "/api/",
data: {"parameters":[123123, {"category":"123"}], "anotherParameter":"anotherValue"}
Would you mind telling how to achieve the same functionality in Java ?
UPD:
I've made it to work with the use of gson + collections + post request.
Here're some guide lines:
Sending POST requests in JAVA.
You might also want to consider performance issues related to different kinds of json parsers
What have you tried so far and what exactly is the problem? Is it that you don't know how to create a connection, that you don't know how to serialize your objects or that you don't know how to make the thing run asynchronously?
I don't think Java has any asynchronous HTTP call methods, you need to use a regular URLConnection and run it in a separate thread. The connection itself is formed like this:
URL url = null;
URLConnection urlConnection = null;
String myURL = "http://example.com/ajax.php?foo=bar";
try {
url = new URL(myURL);
urlConnection = url.openConnection();
} catch (Exception e) {
e.printStackTrace();
return;
}
InputStream responseStream = null;
try {
responseStream = urlConnection.getInputStream();
} catch (IOException e) {
e.printStackTrace();
return;
}
Then you must use something like the AsyncTask class to make it a background job.
For converting your objects to JSON you might want to use the GSON library.