Before anything, I am currently unable to post code info/examples because I am not presently at the machine that has the code. If necessary, I will get the appropriate snippits up when I get to that machine tomorrow.
The Setup
I am implementing GCM communication to local server, as according to Google's example code. Both the client and the server are slight modifications of the example. The server is a Java program (again, pulled almost entirely from the demo code).
The Problem
Currently, the App & Server communicate fine back and forth using the dummy 'echo' setup that is the initial setup of Google's GCM communication example code.
If I move over to the custom message content that I intend on using with GCM is where I get the issue. I can send messages find from the GCM-driven app, but for some reason I am not getting the messages from the server back down to the app.
At current I am testing a basic chat element of the app that is talking to an XMPP server through GCM. So, I can connect to the XMPP server w/Pidgin and see messages coming out of the app, and when I send messages back down, they get sent to the GCM service, but never come out # the App.
Confusions/Questions/Clarifications
I am thoroughly confused because the demo behavior works fine
(message is echoed back to the app).
I am sending to the correct registration ID, I can switch back and forth multiple times between demo behavior and my behavior and it will/will not work accordingly.
I do not have collapse_key, or time_to_live in any of my messages back down to the app, and delay_while_idle is explicitly set to false (not omitted). So there should be no super-fast premature timeout or anything like that (unless I am misunderstanding the behavior of these keys)
It was my understanding there are no 'required' keys inside the data field, is that incorrect? If so, I would greatly appreciate links to any appropriate documentation on required keys in the data field.
I can't imagine there are permission errors since it works with demo functionality.
Currently, the message I am sending from my server back to the GCM app has the following fields, and by my understanding only three of these are required (everything except delay_while_idle?):
to (yes the proper key is here)
delay_while_idle (set to false)
data (JSON string of data)
message_id (autogenerated message ID in the pattern of the example code, essentially a random UUID)
Any help is greatly appreciated. If you feel that some code snippit is important, please let me know what you would like to see.
Ok, so this information was not present in my original post, but upon a bit more debugging this morning I discovered the problem.
In the packaging of my custom message to send along the path Server->GCM->Device, I erroneously put in the key/value pair of "data":"{JSON Dictionary}" rather than
"data": {JSON Dictionary}, and was missing the error being sent back by the GCM service indicating the JSON formatting error.
For any confused by that, the value for the "data" key in your GCM message must be a dictionary, not a string-form of the dictionary (an unintentional error on my part, autopilot fingers for the fail).
Related
I was wondering if there is any way to restrict access to my REST webservices for non ios users. I am using Java and Jersey for my RESTful application.
The aim of this exercise is that since my webservice accepts POSTS of XML data, I would like to restrict the exchanges to an iphone client, to prevent manipulation of xml for security reasons.
the client side is an iphone application developed by us.
(moved to answer from comment by request)
No.
The TCP connection from the iPhone is no different than any other. Anything you receive via that connection as an "identifier" (A User-Agent string, for example) can be generated by any other device capable of making a TCP connection.
From your comment:
is there some kind of validation service, where we could check if the device token is an iphone ie the apple device id?
Even if there were ... you now simply have "security by obscurity"; All I need to do on any other device is send a valid id - you can not tell what is sending it.
Strictly speaking, no - as others have said.
However, since
the client side is an iphone application developed by us.
...you can ship a private key with that application, and hope nobody has enough incentive to bypass whatever security Apple has in place and reverse engineer your app to get their hands on that key.
(Note that this 'security' pattern has failed miserably for DVD encryption, console makers, etc... but if your app is confidential enough and the data you're protecting not worth much, it might be good enough for you).
Once you got that key, you can force authentication in your REST service based on some kind of challenge (initial request, 401 with challenge, client sign challenge with private key and send back with request repeat, server verifies with public key).
It may be helpfull if you make a check of user agent in your code like this :
if(request.getHeader("User-Agent").indexOf("iphone") != -1){
//Execute some code
}
I am writing an Android application that needs to communicate via sms. So for example application will send a message "Hi" to number 123, when number 123 receives the message it will be parsed on their phone by my application and acted on if it was determined to have been sent by my app.
Now I have the sending and receiving/parsing of messages working perfectly but I need a way to identify that the message was sent by my app. I could easily semd the message as "appName:hi" and check to see if the body contains 'appName' but the problem is if the user who receives my message doesn't have my app I would prefer if they just saw "Hi". So I was wondering if theres a way for example to send invisible characters or set some other identifying information either in the sms body or as part of the sms itself ie header. I would like to avoid data sms if possible and my app is intended to be offline.
Any ideas how I could accomplish this?
You can specify port when sending SMS. I do not know how to do this with Android API but since this feature has being supported for years by J2ME Android must support it too.
Your application should listen to this port and send to the same port. So, if user already has your application I think he even will not see the message in his inbox. At least this was the behavior in J2ME. If however he does not have the application yet he will either see it in inbox or will not see it at all. Check this with android. As far as I remember in J2ME it depends on the phone model.
I am trying to make an app that connect to the server.
The app is used by some devices.
If one of the devices upload something to the server, I would like other devices receive the notification about the server has something new.
My question is, how to check the server is change or not? How often we must check the server?
I wonder how the Online Messaging work, because someone send something, we receive the message ASAP
Is the concept can be use with my app?
Sounds like you want to take advantage of Google Could Messaging or GCM for short.
http://developer.android.com/guide/google/gcm/index.html
This could be a lightweight message telling the Android application that there is new data to be fetched from the server (for instance, a movie uploaded by a friend), or it could be a message containing up to 4kb of payload data (so apps like instant messaging can consume the message directly).
GCM is the standard for how your apps "talk" to your servers. Either for a message in it's entirety or just a message to go check the server because it's been updated.
I'm writing a program, that sends email messages and want to know when the receiver receives the email message I've sent to him. How can I do this using JavaMail API?
If I use SMTPMessage, how exactly to deal with the result after I've set the notify options?
SMTPMessage smtpMsg = new SMTPMessage(msg);
smtpMsg.setNotifyOptions(SMTPMessage.NOTIFY_SUCCESS);
There is no standard way of doing this that's accepted and honored across the board. I see that you have some options, though:
Add a header "Return-Receipt-To" with your e-mail address in the value. If the recipient of the e-mail has a client which honors this header, then a return receipt will be sent to you when the e-mail is opened. This is not reliable, mind you, as the user can always decide not to send the receipt, even if he has a client that supports it.
Add an image into your e-mail that loads from your server and put a parameter on the image that includes the user's e-mail address. When the e-mail loads, the image will load from your server. Write a script that collects the e-mail parameter and then delivers a blank image. This is also not reliable, however, as many mail clients prompt users if they wish to download images and they can always choose not to. Also, some (mostly older) e-mail clients do not support images.
Perhaps the most reliable way is not to include the message in your e-mail at all. Include only a link to a website where the message can be read, and include their e-mail address or a unique code in the link. This way, you know exactly who read the message. Of course, this has the downside that people aren't actually getting the message in their inbox, and they also may choose not to go to the website to read it.
Ultimately, I think you're going to have to come up with a creative solution to solve this problem, unless you're happy getting spotty results.
Ok, this is an old discussion, but:
I've found a simple and working solution here (link in spanish).
You just need to add one more field to the header of the message. To achieve this you must use method addHeader of Part class, implemented by Message class. This method receives 2 parameters, type and value of header.
To get confirmation you must add this header:
Disposition-Notification-To
And the value is the mail where we want to send the confirmation answer:
message.addHeader("Disposition-Notification-To","mail#example.com");
ATTENTION: be aware that, nowadays, a lot of mail servers like gmail are discarding this requests, so this will not have effect, but, if you are sure (like me) receiver server allows this, will work like a charm.
please see my answer here (when this questioned was asked about ruby on rails). Tis basically the same answer.
Email open notification - ruby on rails
There is another approach to finding out whether an email has been received or not, it's getting undelivered emails. I've seen a rather good Java implementation here.
They used javax.mail (for mail processing) and guava (for processing strings and collections).
Just add a dummy image with display set to none in your message.And set the src attribute of this image to the url you want to call
You can use SMTP message and request for a delivery status (I don't know if it's coming when the provider receive the mail or if it's when the user open the mail).
JavaMail don't support directly these feature directly and you have to read the RFC 3464.
I also find this thread with examples but didn't try it javamail
You can also look at websina
I am configuring my J2ME app to get an event from the push registry on receipt of an SMS.
Would I be able to access the SMS message, before it reaches the inbox?
I have read that messages sent to port0 of the mobile go directly to native inbox and we can't access it. Is there any way of diverting or even sniffing these messages so as to perform an operation on them from within the J2ME app.
According to this discussion, it is not possible to receive a SMS on port 0 using a MIDlet before it enters the inbox. And while I am not familiar with the
Wireless Messaging API, various other posts seems to indicate that you cannot access the inbox either (I might be wrong on this).
What I think you could do instead is to open a serial connection to the modem part of the phone and listen for an UR code (Unsolicited Response, "events") indicating
that a new SMS is arrived, read it and if it matches your criteria delete it (from the inbox, you still have your copy) using AT commands.
See the AT+CNMA command (New Message Acknowledgement) and similar in the standard (most mobile phone AT commands are by the way specified in 27.007).
For the following I have no idea if if even makes sense/is possible. I only mention it for completeness.
As for processing the SMS before it arrives in the inbox I think the
only option (without it having being sent to a specific port that you listen for) is
SIM application toolkit (which can do a hell of a lot of things), although that is way outside the scope of J2ME and highly obscure and highly un-trivial. Only follow this route if you are really, really desperate.