I am new in android app Development my task is to upload data to localhost server that a user will (fill a form & press submit button to) upload.Tell also if any library is needed.
thanks in advance.
Are you using an HTML page? If so it is like a normla html page where you have a form with your fields and a submit button.
If you have, instead, a UI and wants to upload the data to a remove server there are several options:
Manually
Using some library (OkHttp or Volley)
If you want to do it manually:
HttpURLConnection con = (HttpURLConnection) ( new URL(url)).openConnection();
con.setRequestMethod("POST");
con.setDoInput(true);
con.setDoOutput(true);
con.connect();
con.getOutputStream().write( ("name=" + name).getBytes());
InputStream is = con.getInputStream();
byte[] b = new byte[1024];
while ( is.read(b) != -1)
buffer.append(new String(b));
con.disconnect();
Hope it helps you!
If you like i wrote a post about it in my blog
Related
i'm trying to get the source code from a site using this code
conn = (HttpURLConnection)url.openConnection();
conn.setReadTimeout(10000);
conn.setConnectTimeout(20000);
conn.setRequestMethod("GET");
conn.setDoInput(true);
conn.addRequestProperty("User-Agent", "Mozilla/5.0");
conn.setRequestProperty("Accept-Encoding", "gzip, deflate");
int response = conn.getResponseCode();
if (response = 307){
String locationHeader = conn.getHeaderField("Location");
URL redirectURL = new URL(locationHeader);
...
}
when the server responds with a 307 code i create a new connection with the same parameters as above with the new url given by the server.
this code works fine while following the first 2 redirects, at the third the server gives a relative url that forces a MalformedURLException when my code executes ' new URL(locationHeader); '.
so i tried to fix that adding the ' http://servername/ ' to the ' locationHeader ' string but doing that creates a loop cause the server then redirects to the first url of his redirection chain.
since my browser gets the source code from that server with no problems is there a way to achieve that with HttpURLConnection?
if someone is interested thanks to Fiddler i worked out a solution to this issue.
first i changed the "User-Agent" property to mimic the one of Mozilla then i manually tweaked the cookie the serer was sending in its reply with the relative path.
that did the trick. thank you Fiddler.
I am trying to download files from a server in android and show progress dialog using code very similar to the answer provided in this thread but i am not able to get content length in HttpURLConnection's getContentLength() method. Content length for all files is -1.
For the same file, i get correct content length in iOS app with NSHTTPURLResponse's expectedContentLength method.
Is there some basic difference in the way these methods fetch the content length for an http connection/response?
EDIT 1:
Tried following few things as suggested some answers and comments.
Set Accept-Encoding header to identity
Fetching the content length as string (from header field Content-Length) and then converting it to long
Tried conn.getContent().toString().length() instead of getContentLength()
None of these worked for me yet.
What baffles me most is i get the content length in iOS but not on android.
EDIT 2:
Heres my iOS and Android code for comparison -
iOS:
NSURLRequest *request = [NSURLRequest requestWithURL:self.url cachePolicy:NSURLRequestUseProtocolCachePolicy timeoutInterval:1200.0];
NSURLConnection *connection = [[NSURLConnection alloc] initWithRequest:request delegate:self startImmediately:NO];
[connection scheduleInRunLoop:[NSRunLoop currentRunLoop] forMode:NSDefaultRunLoopMode];
[connection start];
Android:
URL url = new URL(downloadUrlString);
connection = (HttpURLConnection) url.openConnection();
connection .setRequestProperty("Accept-Encoding", "identity");
connection.connect();
The only difference i can see is caching.
So i added following line in android code as well but nothing changed.
connection.setUseCaches(true);
try this:
HttpURLConnection conn = (HttpURLConnection)url.openConnection();
conn .setRequestProperty("Accept-Encoding", "identity");
conn.connect();
if you just need to content length, can you try
conn.getContent().toString().length()
where conn is the HttpURLConnection object
Root cause for this problem turned out to be Cookies.
I am using a web view in one of the activities in my application. Some cookies are stored by the web view. All other REST api and file download requests work without those cookies however for a particular type of requests, the cookies are necessary.
Apparently, android web view and the connection requests do not share cookies out of the box like iOS. As a result i had to make changes in my code to make sure that the HttpUrlConnection uses WebKit's cookie store. I did it using method described in the accepted answer for this question.
Has anyone released code to show the full HTTP request/response headers, any intermediate redirects, and any cookie data for the Android HttpURLConnection? This would be similar to Firefox Web Console
I roughly know how to write this myself, but 1) it's a non-trivial amount of code 2) it's tricky to get this kind of code to work in all instances. So i'm interested in finding a readymade solution. I know how to tcpdump the emulator, but I'm searching for code to print this information into the Android Log class for really quick runtime debugging.
for header fields
URL url = new URL(str_url);
HttpURLConnection conection = (HttpURLConnection) url.openConnection();
conection.setConnectTimeout(TIMEOUT_SOCKET);
conection.setReadTimeout(TIMEOUT_CONNECTION);
conection.addRequestProperty("Accept-Encoding", "gzip");
RedirectLocations locations = new RedirectLocations();
// here u get all header fields and properties write it in logs
conection.getHeaderFields();
conection.getRequestProperties();
// conection.getOutputStream().write(buffer);
// download the file
InputStream is = conection.getInputStream();
// This is file path were a; quiz data will get saved.
// String file_path = context.getDir(folder,Activity.MODE_PRIVATE).getAbsolutePath();
return unzip(is,save_file_path);
for redirects
link
after u get response, again u ve to look for header fields
I am trying to develop an application where I can get the HTML source of any web page. I am able to get the code but when I am trying the same code using some facebook profile links, it gives me an empty string.
I am using HttpURLConnection. I am trying the code as follows:
URL url = new URL(urlPassed);
HttpURLConnection urlc = (HttpURLConnection) url.openConnection();
BufferedInputStream buffer = new BufferedInputStream(urlc.getInputStream());
and I am trying to read that buffer in a loop as buffer.read(by) where "by" is a byte array of size 7024. However, it works fine for all other web pages except facebook pages.
Any reason for this? Any idea to solve this?
I'm trying around with the HttpURLConnection for quite some time now and I tried several solution posted here and on other places, but nothing seems to work.
I have the following architecture:
A Ruby on Rails Web Service (Rest interface with JSON)
An iPhone Client with RestKit
An Android Client with HttpURLConnection
The iPhone Client works like a charm. It connects to the web service with RestKit.
Now the Android Client is a completely different story. I always get a 401 Unauthorized message from the server (which results in a local FileNotFoundException).
The strange thing is, that the iPhone Client gets the same error, but RestKit somehow manages the handle it by sending the same request again. I tried that of course, but I just get the same error twice.
On the Rails Log Output it looks like this:
Started POST "/api/v1/login" for 127.0.0.1 at 2012-05-03 12:44:56 +0200
Processing by Api::V1::ApiController#session_login as JSON
Parameters: {"device"=>{"model"=>"Simulator", "system"=>"Android", "version"=>"Hugo", "name"=>"Android Simulator"}, "email"=>"florian.letz#simpliflow.com", "api"=>{"device"=>{"model"=>"Simulator", "system"=>"Android", "version"=>"Hugo", "name"=>"Android Simulator"}, "email"=>"florian.letz#simpliflow.com", "action"=>"session_login", "controller"=>"api/v1/api"}}
Filter chain halted as :require_login_from_http_basic rendered or redirected
Completed 401 Unauthorized in 0ms (ActiveRecord: 0.0ms)
The exact same message occurs when the iPhone Client connect's but then suddenly a magical second request occurs and it goes through.
On the Android Client I do the following:
HttpURLConnection con = (HttpURLConnection) url.openConnection();
con.setRequestMethod(HTTP_POST);
con.setRequestProperty("Content-Type", "application/json");
con.setRequestProperty("Accept", "application/json");
con.setRequestProperty("Accept-Encoding", "gzip, deflate");
String userpassword = email + ":" + password;
con.setRequestProperty("Authorization", "Basic " + new String(Base64.encodeBase64(userpassword.getBytes())));
String body = jsonLogin.toString();
byte[] body_bytes = body.getBytes();
con.setRequestProperty("Content-Length", "" + Integer.toString(body_bytes.length));
con.setRequestProperty("Content-Language", "en-US");
con.setInstanceFollowRedirects(false);
con.setUseCaches (false);
con.setDoInput(true);
con.setDoOutput(true);
DataOutputStream wr = new DataOutputStream (con.getOutputStream ());
wr.write(body_bytes);
wr.flush ();
wr.close ();
InputStream is = con.getInputStream();
And on the last line the exception occurs.
I've read some things about redirects, but there is no redirect implemented at the server and I do not receive one on the client. I just get the 401 Unauthorized. The code in the web service and the iphone client indicate a quite simple workflow. Just send the data and receive the answer. I don't know where the SECOND login call comes from when the iPhone connects.
Does anyone here have any idea what the problem could be?
Thanks a lot!
EDIT #1:
I have identified the "magical" second request. The RestKit Log shows the following:
Asked if canAuthenticateAgainstProtectionSpace: with authenticationMethod = NSURLAuthenticationMethodDefault
This then results in the second request with quite a buch of headers I cannot make any sense of.
So do you know a way to implement this in Android?