Ok, guys, so I'm recently developing android app that saves user's ID and PASSWORD to SharedPreferences. Now, when the user starts app second time, he will be redirected directly to MainActivity with a few options in listView. And now I have a huge headache and it's driving me REAL crazy. I cannot login to website and fetch the data to my phone. I've tried using Http(s)UrlConnection, HttpClient, but it just doesn't seem to work for me. All I get from POST method is a source code of login page.
Now, there is login page: https://medeine.vgtu.lt/studentams/login.jsp?klb=en
and my target page: https://medeine.vgtu.lt/studentams/pask_stud.jsp <-- I need to fetch data from there
Have you got any thoughts or tips/methods/guides/anything how to do that?
For this you must send two POST requests. In the first request, you need to send login data and save cookies, when the login was successful. In the second request, you need to send saved cookies and you can get the data. Data for POST must be formatted like this: var=value&var2=value2
In your case:
String data = "studKnNr=login&asmKodas=password";
And url for request: https://medeine.vgtu.lt/studentams/submit.jsp
See the following code:
String data = "studKnNr=login&asmKodas=password";
String loginUrl = "https://medeine.vgtu.lt/studentams/submit.jsp";
String Login = POST_req(loginUrl, data, 10000); /*last parameter is a limit of page content length*/
//And after succcessful login you can send the second request:
String pageContent = POST_req(someUrl, "", 10000);
//Methods for sending requests and saving cookie:
//(this doesn't need any changes, you can just paste it in your project)
public String POST_req(String url, String post_data, int len) {
URL addr = null;
try {
addr = new URL(url);
} catch (MalformedURLException e) {
return "Incorrect URL";
}
StringBuffer data = new StringBuffer();
HttpURLConnection conn = null;
try {
conn = (HttpURLConnection) addr.openConnection();
} catch (IOException e) {
return "Open connection error";
}
conn.setRequestProperty("Connection", "keep-alive");
conn.setRequestProperty("Accept-Language", "ru,en-GB;q=0.8,en;q=0.6");
conn.setRequestProperty("Accept-Charset", "utf-8");
conn.setRequestProperty("Accept", "text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8");
conn.setRequestProperty("Cookie", "");
conn.setDoOutput(true);
conn.setDoInput(true);
//conn.setInstanceFollowRedirects(true);
set_cookie(conn);
//POST data:
String post_str = post_data;
data.append(post_str);
try {
conn.connect();
} catch (IOException e) {
return "Connecting error";
}
DataOutputStream dataOS = null;
try {
dataOS = new DataOutputStream(conn.getOutputStream());
} catch (IOException e2) {
return "Out stream error";
}
try {
((DataOutputStream) dataOS).writeBytes(data.toString());
} catch (IOException e) {
return "Out stream error 1";
}
/*If redirect: */
int status;
try {
status = conn.getResponseCode();
} catch (IOException e2) {
return "Response error";
}
if (status == HttpURLConnection.HTTP_MOVED_TEMP || status == HttpURLConnection.HTTP_MOVED_PERM || status == HttpURLConnection.HTTP_SEE_OTHER) {
String new_url = conn.getHeaderField("Location");
String cookies = conn.getHeaderField("Set-Cookie");
URL red_url;
try {
red_url = new URL(new_url);
} catch (MalformedURLException e) {
return "Redirect error";
}
try {
conn = (HttpURLConnection) red_url.openConnection();
} catch (IOException e) {
return "Redirect connection error";
}
//conn.setRequestProperty("Content-type", "text/html");
conn.setRequestProperty("Connection", "keep-alive");
conn.setRequestProperty("Accept-Language", "ru,en-GB;q=0.8,en;q=0.6");
conn.setRequestProperty("Accept-Charset", "utf-8");
conn.setRequestProperty("Accept", "text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8");
conn.setRequestProperty("Cookie", cookies);
conn.setDoOutput(true);
conn.setDoInput(true);
//conn.setInstanceFollowRedirects(true);
}
java.io.InputStream in = null;
try {
in = (java.io.InputStream) conn.getInputStream();
} catch (IOException e) {
return "In stream error";
}
InputStreamReader reader = null;
try {
reader = new InputStreamReader(in, "UTF-8");
} catch (UnsupportedEncodingException e) {
return "In stream error";
}
char[] buf = new char[len];
try {
reader.read(buf);
} catch (IOException e) {
return "In stream error";
}
get_cookie(conn);
return (new String(buf));
}
public void get_cookie(HttpURLConnection conn) {
SharedPreferences sh_pref_cookie = getSharedPreferences("cookies", Context.MODE_PRIVATE);
String cook_new;
String COOKIES_HEADER;
if (conn.getHeaderField("Set-Cookie") != null) {
COOKIES_HEADER = "Set-Cookie";
}
else {
COOKIES_HEADER = "Cookie";
}
cook_new = conn.getHeaderField(COOKIES_HEADER);
if (cook_new.indexOf("sid", 0) >= 0) {
SharedPreferences.Editor editor = sh_pref_cookie.edit();
editor.putString("Cookie", cook_new);
editor.commit();
}
}
public void set_cookie(HttpURLConnection conn) {
SharedPreferences sh_pref_cookie = getSharedPreferences("cookies", Context.MODE_PRIVATE);
String COOKIES_HEADER = "Cookie";
String cook = sh_pref_cookie.getString(COOKIES_HEADER, "no_cookie");
if (!cook.equals("no_cookie")) {
conn.setRequestProperty(COOKIES_HEADER, cook);
}
}
Of course you must send requests in async thread.
Hope it's helpful. And excuse me for my bad english:)