Java API V2 Session Upload

This API is kind of a mess right now.  We need to sort some things out to make it clearer, but for now, this might work:

```

DbxClientV2 client = ...

uploader = client.files.uploadSessionStart();

String sessionId;

try {

    uploader.getBody().write(first_chunk_of_upload)

    sessionId = uploader.finish()

} finally {

    uploader.close()

}

uploader = client.files.uploadSessionAppend(sessionId, offset)

try {

    uploader.getBody().write(second_chunk_of_upload)

    uploader.finish()

} finally {

    uploader.close()

}

cursor = UploadSessionCursor(sessionId, offset);

FileMetadata md = client.files.uploadSessionFinishBuilder(cursor, ...).run(third_chunk_of_upload);

```

I don't have time to test the code right now.  Lemme know if you run into any issues and I'll take a closer look.

I don't believe we have a sample for that, but I'll be sure to pass this along as feedback. 

If you elaborate on what you're stuck on we'll be happy to help though. Please share your code and whatever output/errors you're getting.

Thank you ... I can work from this ... it was not obvious how you to get the session ID.

A comment ... the interface is a little strange ...

I get an OutputStream that I must write to for uploading the initial chunk.

I must supply an InputStream that the API reads from for the middle and last chunks.

Yeah, sorry about that.  We're definitely going to change the interface to make it more consistent.

Hi @Kannan G thanks for the code sample,

at last i have successfully wrote an example and works like charm :)

DbxRequestConfig config = new DbxRequestConfig("dropbox/java-tutorial",
"en_US");
DbxClientV2 client = new DbxClientV2(config, ACCESS_TOKEN);
try {
URL url = new URL(url_d);
// Upload Files to Dropbox
String fileName = url_d.substring(url_d.lastIndexOf('/') + 1,
url_d.length());
HttpURLConnection hc = (HttpURLConnection) url.openConnection();
hc.addRequestProperty("Range", "bytes=0-256");
hc.connect();
DbxFiles.UploadSessionStartUploader re = client.files.uploadSessionStart();
re.getBody().write(IOUtils.toByteArray(hc.getInputStream()));
UploadSessionStartResult sa = re.finish();
String ss = sa.sessionId;
System.out.println(ss);
hc.disconnect();
HttpURLConnection hc1 = (HttpURLConnection) url.openConnection();
hc1.addRequestProperty("Range", "bytes=257-512");
hc1.connect();
UploadSessionAppendBuilder re1 = client.files.uploadSessionAppendBuilder(ss, 257);
re1.run(hc1.getInputStream());
hc1.disconnect();
HttpURLConnection hc2 = (HttpURLConnection) url.openConnection();
hc2.addRequestProperty("Range", "bytes=513-");
hc2.connect();
UploadSessionCursor usc = new UploadSessionCursor(ss, 513);
FileMetadata nn = client.files.uploadSessionFinishBuilder(
usc,
new CommitInfo("/" + fileName, DbxFiles.WriteMode.add,
false, new Date(), false))
.run(hc2.getInputStream());
System.out.println(nn.toStringMultiline());
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} catch (UploadException e) {
e.printStackTrace();
} catch (DbxException e) {
e.printStackTrace();
}

hi @pankaj kumar t. where is url_d, you can post the url that you use?

Christian, it looks like Pankaj's example reads the data to upload from an arbitrary URL, likely specific to their app. When developing your own implementation, you can retrieve the data to upload from wherever it is in your app, e.g., a local file.

hi @christian i had written a logic to upload files to dropbox 

feel free to ask any doubt.

here is the code which upload entire file.

String url_d = "<your download url here>";

long buffer = 33554432; // 32mb buffer
DbxRequestConfig config = new DbxRequestConfig("dropbox/java-tutorial",
"en_US");
DbxClientV2 client = new DbxClientV2(config, ACCESS_TOKEN);
try {
URL url = new URL(url_d);
String sessionId = ";
// Upload Files to Dropbox
String fileName = java.net.URLDecoder.decode(url_d.substring(url_d.lastIndexOf('/') + 1,url_d.length()), "UTF-8");;
HttpURLConnection getLength = (HttpURLConnection) url.openConnection();
getLength.connect();
long size = getLength.getContentLengthLong();
// Start session
HttpURLConnection hc = (HttpURLConnection) url.openConnection();
hc.addRequestProperty("Range", "bytes=0-"+buffer);
hc.connect();
DbxFiles.UploadSessionStartUploader result = client.files.uploadSessionStart();
result.getBody().write(IOUtils.toByteArray(hc.getInputStream()));
UploadSessionStartResult sa = result.finish();
sessionId = sa.sessionId;
hc.disconnect();
if (size > 0) {
//System.out.println("large ");

long s2 = buffer;
long tmp = 0;
//System.out.println("0"+" "+buffer);
while (tmp <= size && (buffer + s2) < size) {
buffer++;
tmp = buffer + s2;
if (tmp < size) {
System.out.println(buffer + "\t" + (tmp)+"\t"+(tmp-buffer));
// Append to session
HttpURLConnection hc1 = (HttpURLConnection) url.openConnection();
hc1.addRequestProperty("Range", "bytes="+buffer+"-"+tmp);
hc1.setReadTimeout(10000);
hc1.connect();
UploadSessionAppendBuilder re1 = client.files.uploadSessionAppendBuilder(sessionId, buffer);
re1.run(hc1.getInputStream());
hc1.disconnect();
buffer = tmp;
}
}
if((tmp+1)+buffer>size){
// finish session
HttpURLConnection hc2 = (HttpURLConnection) url.openConnection();
hc2.addRequestProperty("Range", "bytes="+(tmp+1)+"-"+size);
hc2.setReadTimeout(10000);
hc2.connect();
UploadSessionCursor usc = new UploadSessionCursor(sessionId, (tmp+1));
FileMetadata nn = client.files.uploadSessionFinishBuilder(
usc,
new CommitInfo("/" + fileName, DbxFiles.WriteMode.add,false, new Date(), false))
.run(hc2.getInputStream());
// End
System.out.println("Done");
}
}
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} catch (UploadException e) {
e.printStackTrace();
} catch (DbxException e) {
e.printStackTrace();
}