I want to send my id & password to server and get the response from server. Here is my code. It is not working for the first time. But iam getting the response from server if i execute my application on second time. It is throwing "Post method failed: -1 null" on first time. Where iam wrong?? Why if() block is executing on first time?? could you please tell me.
HttpsURLConnection con = null;
String httpsURL = "https://www.abc.com/login";
String query = "id=xyz&password=pqr";
URL url = new URL(httpsURL);
con = (HttpsURLConnection) url.openConnection();
con.setRequestMethod("POST");
con.setRequestProperty("Content-length", String.valueOf(query.length()));
con.setRequestProperty("Content-Type","application/x-www-form-urlencoded");
con.setRequestProperty("User-Agent","Mozilla/4.0(compatible; MSIE 5.0; Windows 98; DigExt)");
con.setDoInput(true);
con.setDoOutput(true);
DataOutputStream output = new DataOutputStream(con.getOutputStream());
output.writeBytes(query);
output.close();
int respCode = con.getResponseCode();
if (respCode != HttpsURLConnection.HTTP_OK)
{
throw new Exception("POST method failed: " + con.getResponseCode()+ "\t" + con.getResponseMessage()); }
else {
//read the content from server
}
1/ It is recommanded to use apache HttpClient rather than URLConnection (see http://developer.android.com/reference/org/apache/http/impl/client/DefaultHttpClient.html)
2/ for login and password, why not use Http Authentication ? both basic and digest are supported by android.
3/ as for you problem, you don't close the underlying outputStream.
you should do:
OutputStream os = con.getOutputStream();
DataOutputStream output = new DataOutputStream(os);
output.writeBytes(query);
output.close();
os.close();
Check Server service validity with other technology and/or classic java. You didn say in your question if you succeed to discriminate the server from the issue.
from java doc ...getResponseCode returns -1 if no code can be discerned from the response (i.e., the response is not valid HTTP).
Java https post request example : http://www.java-samples.com/java/POST-toHTTPS-url-free-java-sample-program.htm
try to close your outputstream after querying the status and not before...that may help
Here is how you should send POST requests in Android
HttpPost httpGet = new HttpPost(server + "/login?email="+username+"&password="+password);
DefaultHttpClient httpClient = new DefaultHttpClient();
HttpResponse response = httpClient.execute(httpGet);
You can read response using:
response.getEntity().getContent()
Related
I have this situation: there is a Jersey rest web service working via HTTPS. I'm working on an Android code that will POST Json to that service and read response. I managed to connect, from API log i can see that call has been received and no errors are displayed, i also get data in the "InputStream" of the connection, but data is encrypted! Even when i try using plain HTTP connection and run web service in HTTP mode result is the same.
What confuses me is that equal cURL request produces proper output without any issues... Where am i wrong? This is the code i'm using:
URL url = new URL("https://myServer:8780/api/<apicall>");
HttpsURLConnection conn = (HttpsURLConnection) url.openConnection();
// Create the SSL connection
SSLContext sc;
sc = SSLContext.getInstance("TLS");
sc.init(null, null, new java.security.SecureRandom());
conn.setSSLSocketFactory(sc.getSocketFactory());
// set Timeout and method
conn.setReadTimeout(7000);
conn.setConnectTimeout(7000);
conn.setRequestMethod("POST");
conn.setDoInput(true);
conn.setRequestProperty("Accept-Encoding", "gzip");
conn.setRequestProperty("Accept", "application/json");
// Add any data you wish to post here
String json = "{\"test\":\"hello\"}";
byte[] bytes = json.getBytes("UTF-8");
OutputStream out = conn.getOutputStream();
out.write(bytes);
out.flush();
out.close();
String result = new String();
InputStream is = null;
/*if ("gzip".equals(conn.getContentEncoding()))
is = new GZIPInputStream(conn.getInputStream()); THIS WOULD FAIL WITH ERROR MESSAGE THAT CONTENT IS NOT IN GZIP FORMAT!
else*/
is = conn.getInputStream();
BufferedReader in = new BufferedReader(new InputStreamReader(is));
String inputLine;
while ((inputLine = in.readLine()) != null) {
result += inputLine;
}
In the same time, this cURL call (i'm using Linux) works perfectly and returns expected JSON response from the server:
curl -H 'Accept-Encoding: gzip' -X POST https://myServer:8780/api/<apicall> -d '{"test":"hello"}'
EDIT Issue was caused by my server using both "Content-encoding: gzip" and "Transfer-encoding: gzip". When i removed "Transfer-Encoding" issue was solved!
I am trying to login through url and i am getting status code 500 in httpurlconnevtion
public static String excutePost(String targetURL, String urlParameters)
{
URL url;
HttpURLConnection connection = null;
try {
//Create connection
url = new URL(targetURL);
connection = (HttpURLConnection)url.openConnection();
connection.setRequestMethod("POST");
connection.setRequestProperty("Content-Type",
"application/x-www-form-urlencoded");
connection.setRequestProperty("Connection", "Keep-Alive");
connection.setRequestProperty("Content-Length", "" +
Integer.toString(urlParameters.getBytes().length));
connection.setRequestProperty("Content-Language", "en-US");
connection.setRequestProperty("Accept-Encoding", "");
connection.setUseCaches (false);
connection.setDoInput(true);
connection.setDoOutput(true);
//Send request
DataOutputStream wr = new DataOutputStream (
connection.getOutputStream ());
wr.writeBytes (urlParameters);
wr.flush ();
wr.close ();
System.out.println("status :"+connection.getResponseCode());
System.out.println("getErrorStream() :"+connection.getErrorStream());
//Get Response
InputStream is = connection.getInputStream();
BufferedReader rd = new BufferedReader(new InputStreamReader(is));
String line;
StringBuffer response = new StringBuffer();
while((line = rd.readLine()) != null) {
response.append(line);
response.append('\r');
}
rd.close();
return response.toString();
} catch (Exception e) {
e.printStackTrace();
return null;
} finally {
if(connection != null) {
connection.disconnect();
}
}
}
and my params are
String urlParameters =
"pwd1=" + URLEncoder.encode("DEMO123", "UTF-8") +
"&badge=" + URLEncoder.encode("1233", "UTF-8");
i am getting logcat
status :500
getErrorStream() :libcore.net.http.FixedLengthInputStream#417bc5c0
thank you
**EDITED 2**
I have also try with
DataOutputStream dos = new DataOutputStream(connection.getOutputStream());
// Add badge
dos.writeBytes(LINE_START + BOUNDRY + LINE_END);
dos.writeBytes("Content-Disposition: form-data; name='badge';");
dos.writeBytes(LINE_END + LINE_END);
dos.writeBytes("1233");
dos.writeBytes(LINE_END);
// Add password
dos.writeBytes(LINE_START + BOUNDRY + LINE_END);
dos.writeBytes("Content-Disposition: form-data; name='pwd1';");
dos.writeBytes(LINE_END + LINE_END);
dos.writeBytes("DEMO123");
dos.writeBytes(LINE_END);
500 denotes an Internal Server Error. There is probably no error on your side, it's on the server. Even if you are sending something incorrectly and it's causing the server to return 500, it's still a server problem.
Edit:
Okey, the server should rather return something like 400 Bad Request instead of 500 Internal Server Error but I found your error now:
connection.setRequestProperty("Content-Length", Integer.toString(urlParameters.getBytes().length));
...
//Send request
DataOutputStream wr = new DataOutputStream (connection.getOutputStream ());
wr.writeBytes (urlParameters);
The problem here is that your first get the the bytes from urlParameters using getBytes which (quoting javadoc):
Encodes this String into a sequence of bytes using the platform's default charset
And then you write the bytes using DataOutputStream.writeBytes which (quoting javadoc):
Each character in the string is written out, in sequence, by discarding its high eight bits.
In summary, your Content-Length doesn't match the data. So the server returns you the
java.io.IOException: exceeded content-length limit of 20 bytes
Solution:
//consider urlParameters.getBytes("UTF-8") method instead of using default encoding
byte[] bodyData = urlParameters.getBytes();
connection.setRequestProperty("Content-Length", Integer.toString(bodyData.length));
...
//Send request
InputStream out = connection.getOutputStream();
out.write(bodyData);
Edit 2:
Edit 1 is definitely valid, however, looking over the problem again, I believe the error is definitely caused by the server. I think the server is returning a bad Content-Length header and, when the data is read on Android, the system realizes there is more data coming from the server than it should be by the Content-Length and throws an exception, also replacing the status code by 500 because it really is a server error.
Edit 3:
connection.setRequestProperty("Content-Language", "en-US");
connection.setRequestProperty("Accept-Encoding", "");
Instead of setting Content-Language which is not neccessary here, you should set Content-Encoding to UTF-8 and instead of empty Accept-Encoding, you should add the real expected MIME-type. I believe this is a server error, but you maybe it won't appear if you set the request headers correctly.
Status code 500 means Internal Server Error. Why this is thrown at you, only the server behind targetURL knows.
Verify that you're making correct usage of the API. Taking a look at the response's body (besides the status code) may provide a hint.
I have a REST service I can't alter, with methods for uploading an image, encoded as a Base64 string.
The problem is that the images can go up to sizes of 5-10MB, perhaps more. When I try to construct a Base64 representation of an image of this size on the device, I get an OutOfMemory exception.
I can however encode chunks of bytes at a time (3000 let's say), but this is useless as I would need the whole string to create a HttpGet/HttpPost object:
DefaultHttpClient client = new DefaultHttpClient();
HttpGet httpGet = new HttpGet("www.server.com/longString");
HttpResponse response = client.execute(httpGet);
Is there a way of going around this?
Edit: trying to use Heiko Rupp's suggestions + the android doc, I get an exception ("java.io.FileNotFoundException: http://www.google.com") at the following line: InputStream in = urlConnection.getInputStream();
try {
URL url = new URL("http://www.google.com");
HttpURLConnection urlConnection = (HttpURLConnection) url.openConnection();
urlConnection.setDoOutput(true);
urlConnection.setChunkedStreamingMode(0);
OutputStream out = new BufferedOutputStream(urlConnection.getOutputStream());
out.write("/translate".getBytes());
InputStream in = urlConnection.getInputStream();
BufferedReader r = new BufferedReader(new InputStreamReader(in));
StringBuilder total = new StringBuilder();
String line;
while ((line = r.readLine()) != null) {
total.append(line);
}
System.out.println("response:" + total);
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
Am I missing something? The GET request that I need to execute looks like this:
"http://myRESTService.com/myMethod?params=LOOONG-String", so the idea was to connect to http://myRESTService.com/myMethod and then output a few characters of the long string at a time. Is this correct?
You should try to use the URLConnection instead of the apache http client, as this does not require you to hold the object to send in memory, but instead you can do something like:
pseudocode!
HttpUrlConnection con = restUrl.getConnection();
while (!done) {
byte[] part = base64encode(partOfImage);
con.write (part);
partOfImage = nextPartOfImage();
}
con.flush();
con.close();
Also in Android after 2.2 Google recommends the URLConnection over the http client. See the description of DefaultHttpClient.
The other thing you may want to look into is the amount of data to be sent. 10 MB + base64 will take quite a while to transfer (even with gzip compression, which the URLConnection transparently enables if the server side accepts it) over a mobile network.
You must read docs for this REST service, no such service will require you to send such long data in GET. Images are always sent as POST. POST data is always at the end of request and allows to be added iteratively.
Context: In Android, when I use Java's HttpURLConnection object as shown below, I see the POST body correctly on the server side. However, when I use what I believe is the equivalent HttpClient code, the POST body is empty.
Question:
What am I missing?
Server-side is a Django-python server. I have set up a debug point at the entry point of this endpoint but the post body is already empty. How can I debug through it to find out why the body is null?
Note: I already looked at this , but the solution does not work for me.
Code: using HttpURLConnection - this works:
try {
URL url = new URL("http://10.0.2.2:8000/accounts/signup/");
String charset = "UTF-8";
HttpURLConnection connection = (HttpURLConnection) url.openConnection();
connection.setRequestMethod("POST");
connection.setDoOutput(true);
connection.setRequestProperty ("Authorization", "Basic base64encodedstring==");
connection.setRequestProperty("Accept-Charset", charset);
connection.setRequestProperty("Content-Type",
"application/x-www-form-urlencoded; charset=" + charset);
connection.setDoInput(true);
StringBuilder sb = new StringBuilder();
sb.append("appver=6&user=value1pw=&hash=h1");
OutputStreamWriter outputWriter = new
OutputStreamWriter(connection.getOutputStream());
outputWriter.write(sb.toString());
outputWriter.flush();
outputWriter.close();
// handle response
} catch () {
// handle this
}
============================================================
Code: using Apache httpclient - does NOT work - server gets empty POST body:
HttpPost mHttpPost = new HttpPost(""http://10.0.2.2:8000/accounts/signup/"");
mHttpPost.addHeader("Authorization", "Basic base64encodedstring==");
mHttpPost.addHeader("Content-Type",
"application/x-www-form-urlencoded;charset=UTF-8");
mHttpPost.addHeader("Accept-Charset", "UTF-8");
String str = "appver=6&user=value1pw=&hash=h1"; // same as the above
StringEntity strEntity = new StringEntity(str);
mHttpPost.setEntity(strEntity);
HttpUriRequest pHttpUriRequest = mHttpPost;
DefaultHttpClient client = new DefaultHttpClient();
httpResponse = client.execute(pHttpUriRequest);
// more code
I figured the reason why this was happening:
The authorization header in the POST request had an extra new line character "\n" - this was causing the request to go through to the server side handler, but with the body getting cut off. I have never noticed this behavior before.
I have to connect to a webserver from android and I have to access a webservice and a webpage from the webserver. Can anybody help me? Please give step by step process with some code snippets because I am new to android and I don't know anything in connecting to a webserver.
You can use an HttpClient:
HttpClient httpClient = new DefaultHttpClient();
HttpGet httpGet = new HttpGet(uri);
HttpResponse httpResponse = httpClient.execute(httpGet);
BufferedReader reader = new BufferedReader(
new InputStreamReader(httpResponse.getEntity().getContent()));
// user reader to read & parse response
reader.close();
Parsing the response obviously depends on the format (e.g. SOAP, JSON, etc.)
You haven't given very much info (what kind of web page, XML/JSON/HTML/etc. ?). But the basic principles of regular Java apply. Using URL and InputStream:
URL url = new URL(...);
InputStream is = url.openStream();
And from there it depends what kind of data you're dealing with.
If you don't want to use an additional library, here is a means for sending an "id" and "name" to a server:
URL url = null;
try {
String registrationUrl = String.format("http://myserver/register?id=%s&name=%s", myId, URLEncoder.encode(myName,"UTF-8"));
url = new URL(registrationUrl);
URLConnection connection = url.openConnection();
HttpURLConnection httpConnection = (HttpURLConnection) connection;
int responseCode = httpConnection.getResponseCode();
if (responseCode == HttpURLConnection.HTTP_OK) {
Log.d("MyApp", "Registration success");
} else {
Log.w("MyApp", "Registration failed for: " + registrationUrl);
}
} catch (Exception ex) {
ex.printStackTrace();
}
You could just as easily send other data via this URI "GET" style, but if you need to send something more detailed a POST will be required.
Note: Originally posted to answer a similar question here: How to connect android to server