Connect to Azure DocumentDB from Android

Question

Has anyone experienced connecting to Azure\'s documentdb from android? I have tried using the new Java SDK, however it doesn\'t seem to be supported within android due to some

Answer 1

Okay, this was a nightmare to solve. Nine hours later... -_-'. Long story short, here is some code that will actually work successfully. This code isn't perfect, and is dependent on Retrofit

First, this is an example "Service" interface in Retrofit:

import retrofit.Callback;
import retrofit.http.Body;
import retrofit.http.Header;
import retrofit.http.POST;

public interface MyPojoService {
    @POST("/dbs/[db_id]/colls/[collection_id]/docs")
    void addDocument(@Header("authorization") String authorization, @Header("x-ms-date") String date, @Body MyPojo myPojo, Callback<MyPojo> cb);
}

Next, we have our initial setup fields within the class that will call DocumentDB:

// Replace with your DocumentDB master key.
private static final String MASTER_KEY = "[Insert Key Here]";

//Gson instance.
private Gson gson = new Gson();

Now we'll have our method that executes against the RESTful endpoint:

public void callDocumentDB() {
    SimpleDateFormat formatter = new SimpleDateFormat("EEE, dd MMM yyyy HH:mm:ss 'GMT'", Locale.US);
    formatter.setTimeZone(TimeZone.getTimeZone("GMT"));
    String headerDate = formatter.format(new Date()).toLowerCase();  //According to the spec the format matters here.  Make sure to use this format on the header dates.


    MyPojo myPojo = new MyPojo();
    myPojo.id = UUID.randomUUID().toString(); //This is the only required field, and does not have to be a UUID.

    RestAdapter restAdapter = new RestAdapter.Builder()
            .setEndpoint("https://[INSERT DB NAME HERE].documents.azure.com")
            .build();

    MyPojoService service = restAdapter.create(MyPojoService.class);

    service.addDocument(generateAuthHeader("post", "docs", "[INSERT COLLECTION ID HERE]", headerDate, MASTER_KEY), headerDate, myPojo, new Callback<MyPojo>() {
        @Override
        public void success(MyPojo myPojo, Response response) {
            //[INSERT API SUCCESSFUL CALL LOGIC HERE]
        }

        @Override
        public void failure(RetrofitError error) {
            throw error;
        }
    });
}

Lastly we have the method that generates the authorization header. This method was a nightmare to put together, but it works properly to the spec:

private String generateAuthHeader(String verb, String resourceType, String resourceId, String date, String masterKeyBase64) throws Exception
{
    //Decode the master key, and setup the MAC object for signing.
    byte[] masterKeyBytes = Base64.decode(masterKeyBase64, Base64.NO_WRAP);
    Mac mac = Mac.getInstance("HMACSHA256");
    mac.init(new SecretKeySpec(masterKeyBytes, "HMACSHA256"));

    //Build the unsigned auth string.
    String stringToSign = verb + "\n"
            + resourceType + "\n"
            + resourceId + "\n"
            + date + "\n"
            + "\n";

    //Sign and encode the auth string.
    String signature = Base64.encodeToString(mac.doFinal(stringToSign.toLowerCase().getBytes("UTF8")), Base64.NO_WRAP);

    //Generate the auth header.
    String authHeader = URLEncoder.encode("type=master&ver=1.0&sig=" + signature, "UTF8");

    return authHeader;
}

NOTE: Please be aware that generateAuthString and MyPojoService are setup to use the x-ms-date header instead of the date header. There is a bug with the current version of Azure's DocumentDB that seems to be keeping the generated token from authorizing correctly.

I hope this helps, and saves you some time.