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Microsoft Graph: Requesting an Extension returns http 400 bad request

I added an open extension to an event in a calendar and am trying to read it back.
Here is the url:
https://graph.microsoft.com/v1.0/users/{userid}/calendars/{calendarId}=/events?$expand=Extensions($filter=Id eq 'c.i.m.p.server.entities.outlook.Event')
I cannot get this to work in a Java program. The following combinations do work:
It works my Java program if I remove the $expand... parameter. I can also ask for certain fields, that works too.
The request works in Postman (I just have to set the token)
The request works in Graph Explorer when I log in as the owner of the calendar
Here is the extension (inside one of the events) when I use Postman to read the event. It is the last item in the event:
"extensions#odata.context": "https://graph.microsoft.com/v1.0/$metadata#users('{userid}')/calendars('{calendarId}')/events('{eventId})/extensions",
"extensions": [
{
"#odata.type": "#microsoft.graph.openTypeExtension",
"id": "Microsoft.OutlookServices.OpenTypeExtension.c.i.m.p.server.entities.outlook.Event",
"extensionName": "c.i.m.p.server.entities.outlook.Event",
"adherentId": "12346",
"timeSlotID": "346463"
}
]
Here is the Java code (Java 8, using java.io and java.net libraries):
private static void doSomething(String _accessToken) throws IOException {
String urlString = "https://graph.microsoft.com/v1.0/users/{userId}/calendars/{calendarId}/events?$expand=Extensions($filter=Id eq 'c.i.m.p.server.entities.outlook.Event')";
URL url = new URL(urlString);
Proxy webProxy
= new Proxy(Proxy.Type.HTTP, new InetSocketAddress({proxy-address}, {port}));
HttpURLConnection connection = (HttpURLConnection) url.openConnection(webProxy);
// Set the appropriate header fields in the request header.
connection.setRequestProperty("Authorization", "Bearer " + _accessToken);
connection.setRequestProperty("Accept", "application/json");
connection.setDoOutput(true);
connection.setReadTimeout(5000);
connection.setRequestMethod(HttpMethod.GET);
try {
connection.connect();
int responseCode = connection.getResponseCode();
System.out.println("execute(), response code = " + responseCode);
String responseMessage = connection.getResponseMessage();
System.out.println("execute(), response Message = " + responseMessage);
String responseString = null;
try {
InputStream ins = connection.getInputStream();
BufferedReader br=new BufferedReader(new InputStreamReader(ins));
StringBuffer sb=new StringBuffer();
String line;
while ((line=br.readLine()) != null) {
sb.append(line);
}
responseString = sb.toString();
} catch (Exception e) {
System.out.println("Could not get input stream from response, error is " + e.toString());
}
System.out.println("execute(), httpResult = " + responseString);
} catch (IOException e) {
System.out.println(".execute(), IOException : " + e.toString());
} finally {
connection.disconnect();
}
}
How do I fix this? Thanks!

400 means bad request. It could be because of url encoding. Url encode the query string.
Something like
String query = "Extensions($filter=Id eq 'c.i.m.p.server.entities.outlook.Event'";
String url = "https://graph.microsoft.com/v1.0/users/{userId}/calendars/{calendarId}/events?
$expand=" + URLEncoder.encode(query, StandardCharsets.UTF_8.name());
Alternatively you could use graph service java api based on your need which will help abstract all the interactions for you or you could use any of the rest clients available.

First of all, you should provide more info on the error - Stacktrace and error message. But 400 code indicates that was a user mistake, meaning that you are sending an invalid request. Since you say that postman request works then compare all the headers that are sent by postman and see if your code misses some hearer. As for the code, instead of coding your own Http client functionality I would suggest using 3d party Http client. Here are a few suggestions:
Apache Http client - very popular and well known 3d party Http Client
OK Http client - Open-source Http client. Here is tutorial
MgntUtils Http client - very simple 3d party HttpClient: Provided in MgntUtils Open source library (written by me). Very simple in use. Take a look at Javadoc. Library itself provided as Maven artifacts and on Git (including source code and Javadoc).

OkHttp Reverse Http

How to implement reverse http as described in link using OkHttp
Currently my implementation is something like
Issue is I have to parse http responses which I don't feel safe, its just a coarse implementation, if someone can provide a better alternative
String request = "POST /reverse HTTP/1.1\r\n" +
"Upgrade: PTTH/1.0\r\n" +
"Connection: Upgrade\r\n" +
"\r\n";
Socket socket = null;
try {
socket = client.socketFactory().createSocket(ip, port);
final PrintWriter out = new PrintWriter(socket.getOutputStream(), true);
final BufferedReader in = new BufferedReader(new InputStreamReader(socket.getInputStream()));
// send the reverse http request
out.write(request);
out.flush();
// read the reverse http response
String reverseResponse = readResponse(in);
if (!reverseResponse.trim().startsWith("HTTP/1.1 101 Switching Protocols")) {
throw new IOException("can't setup reverse connection");
}
while (!stopped) {
String eventData = readResponse(in);
out.write("HTTP/1.1 200 OK\r\n" +
"Content- Length: 0\r\n\" + " +
"\r\n");
out.flush();
}
} catch (Exception e) {
e.printStackTrace();
} finally {
if (socket != null) {
try {
socket.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}

Trivia: Coincidentally, there is a different guy who drafted a similar solution and coincidentally named it reverse-http as well. This spec has a Reference Java Implementation, but not useful to you, since you are in no control of the server side.
On track:
I could find a Javascript implementation for the reverse-http that you are interested in here. Take a look for implementation hints, but, I guess you already have details.
For your problem, you would need a code fragment that can handle http requests (an http server functionality), while being embedded in a http client library.
Using Okhttp (I hope you are referring this) to achieve what you want may be a bit of work. It provides Websocket support, which is a more evolved version of reverse-http. So, you may try customizing the Websocket implementation of okhttp for your case.
A simplistic solution like yours, where you need not parse the http response can be achieved by adapting the code of popular NanoHTTPD library. Latest releases have added more dependency but an older release has just 1 java file, with no dependency and ideal for such adaptations.

Apache Jackrabbit webDAV PUT Method.

beginning to work with Jackrabbit 2.6.3 and commons httpclient 3.
I've written a simple webDav client to upload a file to a server and want to test it against jackrabbit's standalone server's default repository. Simply I just want to put a file in the default repository.
my httpclient connects and the method begins buffering my file. Trouble is, I can't seem to work what URL I should point my http method at to correctly put it in the repository. The standalone server is running on:
http://localhost:8080.
I seem to either get a 405 PUT not supported or 404 or 403 or the even more curious "repository '/' does not begin with '/default' for all the urls I've tried. I can see the default repository content if I point my browser at:
http://localhost:8080/repository/default/
Simply, my question is, what is the url to do this with a PutMethod? As rudimentary as that sounds.
I've included some truncated code for the class I've written, specifically the method I'm working with at the moment, I think it should be enough to show my approach is correct.
public void insertFile(byte[] content, String id) throws Exception {
PutMethod httpMethod = new PutMethod("http://localhost:8080/repository/default/");
InputStream is = new ByteArrayInputStream(content);
FileMetaData meta = new FileMetaData();
meta.address = destUri;
meta.id = id;
meta.mimeType = Files.probeContentType(Paths.get(meta.address));
RequestEntity requestEntity = new InputStreamRequestEntity(is, meta.mimeType);
httpMethod.setRequestEntity(requestEntity);
try {
int statusCode = client.executeMethod(httpMethod);
if (statusCode != HttpStatus.SC_OK) System.err.println("Method failed: " + httpMethod.getStatusLine());
byte[] responseBody = httpMethod.getResponseBody();
System.out.println(new String(responseBody));
} catch (HttpException e) {
System.err.println("Fatal protocol violation: " + e.getMessage());
e.printStackTrace();
} catch (IOException e) {
System.err.println("Fatal transport error: " + e.getMessage());
e.printStackTrace();
} finally {
httpMethod.releaseConnection();
}
}
I'm sure it's a simple answer, but trawling the docs don't seem to show up any resources or tutorials relating to this. Any help appreciated.

Really silly, totally thought that the requestEntity would send some data on file and use that as a file name, instead I have to specify that myself. PROTIP: Step away from the computer for 5 - 10 minutes. For anyone else with my issue it should be '"yourUrl/repository/default" + fileName'. Easy.

Incrementally handling twitter's streaming api using apache httpclient?

I am using Apache HTTPClient 4 to connect to twitter's streaming api with default level access. It works perfectly well in the beginning but after a few minutes of retrieving data it bails out with this error:
2012-03-28 16:17:00,040 DEBUG org.apache.http.impl.conn.SingleClientConnManager: Get connection for route HttpRoute[{tls}->http://myproxy:80->https://stream.twitter.com:443]
2012-03-28 16:17:00,040 WARN com.cloudera.flume.core.connector.DirectDriver: Exception in source: TestTwitterSource
java.lang.IllegalStateException: Invalid use of SingleClientConnManager: connection still allocated.
at org.apache.http.impl.conn.SingleClientConnManager.getConnection(SingleClientConnManager.java:216)
Make sure to release the connection before allocating another one.
at org.apache.http.impl.conn.SingleClientConnManager$1.getConnection(SingleClientConnManager.java:190)
I understand why I am facing this issue. I am trying to use this HttpClient in a flume cluster as a flume source. The code looks like this:
public Event next() throws IOException, InterruptedException {
try {
HttpHost target = new HttpHost("stream.twitter.com", 443, "https");
new BasicHttpContext();
HttpPost httpPost = new HttpPost("/1/statuses/filter.json");
StringEntity postEntity = new StringEntity("track=birthday",
"UTF-8");
postEntity.setContentType("application/x-www-form-urlencoded");
httpPost.setEntity(postEntity);
HttpResponse response = httpClient.execute(target, httpPost,
new BasicHttpContext());
BufferedReader reader = new BufferedReader(new InputStreamReader(
response.getEntity().getContent()));
String line = null;
StringBuffer buffer = new StringBuffer();
while ((line = reader.readLine()) != null) {
buffer.append(line);
if(buffer.length()>30000) break;
}
return new EventImpl(buffer.toString().getBytes());
} catch (IOException ie) {
throw ie;
}
}
I am trying to buffer 30,000 characters in the response stream to a StringBuffer and then return this as the data received. I am obviously not closing the connection - but I do not want to close it just yet I guess. Twitter's dev guide talks about this here It reads:
Some HTTP client libraries only return the response body after the
connection has been closed by the server. These clients will not work
for accessing the Streaming API. You must use an HTTP client that will
return response data incrementally. Most robust HTTP client libraries
will provide this functionality. The Apache HttpClient will handle
this use case, for example.
It clearly tells you that HttpClient will return response data incrementally. I've gone through the examples and tutorials, but I haven't found anything that comes close to doing this. If you guys have used a httpclient (if not apache) and read the streaming api of twitter incrementally, please let me know how you achieved this feat. Those who haven't, please feel free to contribute to answers. TIA.
UPDATE
I tried doing this: 1) I moved obtaining stream handle to the open method of the flume source. 2) Using a simple inpustream and reading data into a bytebuffer. So here is what the method body looks like now:
byte[] buffer = new byte[30000];
while (true) {
int count = instream.read(buffer);
if (count == -1)
continue;
else
break;
}
return new EventImpl(buffer);
This works to an extent - I get tweets, they are nicely being written to a destination. The problem is with the instream.read(buffer) return value. Even when there is no data on the stream, and the buffer has default \u0000 bytes and 30,000 of them, so this value is getting written to the destination. So the destination file looks like this.. " tweets..tweets..tweeets.. \u0000\u0000\u0000\u0000\u0000\u0000\u0000...tweets..tweets... ". I understand the count won't return a -1 coz this is a never ending stream, so how do I figure out if the buffer has new content from the read command?

The problem is that your code is leaking connections. Please make sure that no matter what you either close the content stream or abort the request.
InputStream instream = response.getEntity().getContent();
try {
BufferedReader reader = new BufferedReader(
new InputStreamReader(instream));
String line = null;
StringBuffer buffer = new StringBuffer();
while ((line = reader.readLine()) != null) {
buffer.append(line);
if (buffer.length()>30000) {
httpPost.abort();
// connection will not be re-used
break;
}
}
return new EventImpl(buffer.toString().getBytes());
} finally {
// if request is not aborted the connection can be re-used
try {
instream.close();
} catch (IOException ex) {
// log or ignore
}
}

It turns out that it was a flume issue. Flume is optimized to transfer events of size 32kb. Anything beyond 32kb, Flume bails out. (The workaround is to tune event size to be greater than 32KB). So, I've changed my code to buffer 20,000 characters at least. It kind of works, but it is not fool proof. This can still fail if the buffer length exceeds 32kb, however, it hasn't failed so far in an hour of testing - I believe it has to do with the fact that Twitter doesn't send a lot of data on its public stream.
while ((line = reader.readLine()) != null) {
buffer.append(line);
if(buffer.length()>20000) break;
}

HttpsURLConnection Connection Problems

I'm a problem with a HttpsURLConnection that I can't seem to solve. Basically, I'm sending up some info to a server and if some of that data is wrong, the server sends me a 500 response code. However, it also sends a message in the response telling me which bit of data was wrong. The problem is that the message is always empty when I read it in. I think this is because a filenotfound exception always gets thrown before the stream can be read. Am I right? I tried reading the errorstream as well but this is always empty. Here's a snippet:
conn = (HttpsURLConnection) connectURL.openConnection();
conn.setDoOutput(true);
conn.setConnectTimeout(30000);
conn.setReadTimeout(30000);
conn.setRequestMethod("POST");
conn.setRequestProperty("Content-Length",
Integer.toString(outString.getBytes().length));
DataOutputStream wr = new DataOutputStream(conn
.getOutputStream());
wr.write(outString.getBytes());
wr.flush();
wr.close();
if(conn.getResponseCode>400{
String response = getErrorResponse(conn);
public String getErrorResponse(HttpsURLConnection conn) {
Log.i(TAG, "in getResponse");
InputStream is = null;
try {
//is = conn.getInputStream();
is = conn.getErrorStream();
// scoop up the reply from the server
int ch;
StringBuffer sb = new StringBuffer();
while ((ch = is.read()) != -1) {
sb.append((char) ch);
}
//System.out.println(sb.toString());
return sb.toString();
// return conferenceId;
}
catch (Exception e){
e.printStackTrace();
}
}

So just to follow up on this, here is how I solved it:
public static String getResponse(HttpsURLConnection conn) {
Log.i(TAG, "in getResponse");
InputStream is = null;
try {
if(conn.getResponseCode()>=400){
is = conn.getErrorStream();
}
else{
is=conn.getInputStream();
}
...read stream...
}
It seems that calling them like this produced an error stream with a message. Thanks for the suggestions!

Try setting content-type request property to "application/x-www-form-urlencoded"
The same is mentioned on this link:
http://developers.sun.com/mobility/midp/ttips/HTTPPost/
The Content-Length and Content-Type headers are critical because they tell the web server how many bytes of data to expect, and what kind, identified by a MIME type.
In MIDP clients the two most popular MIME types are application/octet-stream, to send raw binary data, and application/x-www-form-urlencoded, to send name-value pairs

Are you in control of the server? In other words, did you write the process that runs on the server and listens to the port you're trying to access?
If you did, then you should also be able to debug it and see why your process returns 404.
If you didn't, then describe your architecture (HTTP server, the component it invokes to respond to your HTTP(S) request, etc) and we'll take it from there.
In the very simplest case, of an HTTP server being an Apache server yielding control to some PHP script, it means that Apache couldn't assign your request to anything. Most likely a Web server misconfiguration. Provide some more details and we'll help you out.