java - How to implement Facebook Realtime Update Subscription with callback URL -

how implement facebook realtime api

1. configure facebook app , install app on facebook pages/users want updates for.

2. we need maintain callback url facebook able post updates. jersey based implementation example:

           @path("/social/facebook/update")         public class facebookrealtimeapiresource         {             private static final string hub_mode = "hub.mode";             private static final string hub_challenge = "hub.challenge";             private static final string hub_verify_token = "hub.verify_token";              public facebookrealtimeapiresource()             {                 // desired implementation here             }              @get             @produces(mediatype.text_html)             public void validatefacebookrequest(             @defaultvalue("") @queryparam(hub_mode) string hubmode,             @defaultvalue("") @queryparam(hub_challenge) string hubchallenge,             @defaultvalue("") @queryparam(hub_verify_token) string hubverifytoken,             @context httpservletrequest request,             @context httpservletresponse response)             {                  try                 {                     // hubverifytoken based validation if desired                            response.setstatus(httpservletresponse.sc_ok);                     response.getwriter().write(hubchallenge);                     response.getwriter().flush();                     response.getwriter().close();                 }                 catch (ioexception exc)                 {                     throw new webapplicationexception(response.status.bad_request);                 }             }              @post             @consumes(mediatype.application_json)             public void processfacebookrealtimeupdate(@context httpservletrequest request, inputstream inputstream)             {                 stringbuilder sb = new stringbuilder();                 string newline = system.getproperty("line.separator");                 string line;                 string json = "";                  try                 {                     bufferedreader reader = new bufferedreader(new inputstreamreader(inputstream, request.getcharacterencoding()));                     while ((line = reader.readline()) != null)                     sb.append(line).append(newline);                 }                 catch (exception exc)                 {                     throw new webapplicationexception(response.status.bad_request);                 }                 json = sb.tostring(); // use json string desired purpose             }         } 

3. install app page , subscribe page updates

           public class facebookrealtimesubscriber         {             private accesstoken appaccesstoken = null;             private string appsecret = // app secret             private string useraccesstoken = // access token user owns page, generated using app             private string applicationid = // application id             private string callbackurl = "<your context root>/social/facebook/update";             private string pagename = // page name want install app             private facebookclient client = null;             private final string subscribedappsedge = "/subscribed_apps";             private final string appsubscriptions = "/subscriptions";             private final string verifytoken = "anyrandomverifytoken";             // below fields can subscribed page object             private final string pagefields = "feed,ratings,name,picture,category,description,founded,company_overview,conversations,mission,products,general_info,location,hours,parking,public_transit,phone,email,website,attire,payment_options,culinary_team,general_manager,price_range,restaurant_services,restaurant_specialties,videos,release_date,genre,starring,screenplay_by,directed_by,produced_by,studio,awards,plot_outline,network,season,schedule,written_by,band_members,hometown,current_location,record_label,booking_agent,press_contact,artists_we_like,influences,band_interests,bio,affiliation,birthday,personal_info,personal_interests,members,built,features,mpg,checkins,productlists";              public static void main(string[] args)             {                 new facebookrealtimesubscriber().subscribe();             }              private void subscribe()             {                 string pageaccesstoken = "";                 string pageid = "";                 client = new defaultfacebookclient(version.version_2_3);                 appaccesstoken = client.obtainappaccesstoken(applicationid, appsecret);                 client = new defaultfacebookclient(useraccesstoken, version.version_2_3);                 connection<account> pages = client.fetchconnection("me/accounts", account.class);                 list<account> accounts = pages.getdata();                 (account account : accounts)                 {                     if (pagename.equals(account.getname()))                     {                         pageaccesstoken = account.getaccesstoken();                         pageid = account.getid();                     }                 }                 client = new defaultfacebookclient(pageaccesstoken, appsecret, version.version_2_3);                 // subscribe app page                 object obj = client.publish(pageid + subscribedappsedge, jsonobject.class, parameter.with("id", long.valueof(pageid)));                 system.out.println(obj.tostring());                 // list subscriptions app                 obj = client.fetchobject(pageid + subscribedappsedge, jsonobject.class);                 system.out.println(obj.tostring());                 // subscribe page updates app                 client = new defaultfacebookclient(appaccesstoken.getaccesstoken(), appsecret, version.version_2_3);                 obj = client.publish(applicationid + appsubscriptions,                 jsonobject.class,                 parameter.with("object", "page"),                 parameter.with("callback_url", callbackurl),                 parameter.with("fields", pagefields),                 parameter.with("verify_token", verifytoken));                 system.out.println(obj);                 // subscriptions app                 obj = client.fetchobject(applicationid + appsubscriptions, jsonobject.class);                 system.out.println(obj);             }         }