Android: sending notifications

Until now, my "Home server" Google application (running in the cloud :-)) was using basic XMPP for sending sensor notifications to my phone. With that, each time a sensor changed status, a small text message was sent to me, appearing in my Google Talk application, telling me what sensor changed, the time etc.
Easy, simple, very basic: a few lines of code, done. Even an event history for free!

However this basic solution started to be annoying:

  • No easy way to integrate the notifications with my "Client" Android application.
  • Impossible to use this if the Android Google Talk application got upgraded to "Hangouts": I tried and indeed, I never got a single message when using Hangouts. Apparently, this is a known limitation?

Luckily last month I finally discovered Google Cloud Messaging and had a bit of time to "practice" during the holidays. In short, it makes it possible to easily received/send messages from/to an Android device; the sender can be as simple as an HTTP POST or a few Java calls using an advanced API wrapping up the GCM possibilities.

Now I almost finished the switch from XMPP to GCM, and the result is nice: there is almost no delay (1 second?) between the moment I trigger a sensor and my Android application showing it!


Besides that, I did not yet manage to get the Z-Wave Alarm command class working on my system. Unfortunately no answers from the Z-Wave Me forum so far :-( and well... it seems the forums got abandoned and assaulted by advertisement bots so... May be everybody is at CES 2014?


Comments

Post a Comment

Popular posts from this blog

ZWay: getting the device list.

Back after a while... and a son! Here is a piece of code that can be used with the latest version of the ZWay library. It makes it possible to retrieve the Z-Wave device list and display the device names and associated XML file (each recognized device can be associated to an XML that contains a bunch of meta-data: name, description etc.). int main(int argc, char ** argv) { ZWay theZWay; ZWError result; memset(&theZWay, 0, sizeof(theZWay)); result = zway_init(&theZWay, "/dev/ttyAMA0", "/home/pi/src/razberry-proxy/config", "/home/pi/src/razberry-proxy/translations", "/home/pi/src/razberry-proxy/ZDDX", stdout, Warning); if (result == NoError) { result = zway_start(theZWay, &terminationCb); if (result == NoError) { printf("Discovering...\n"); result = zway_discover(theZW
Read more

First steps with the ZWay library

The Z-Wave "RaZberry" installation comes with everything needed to be able to do some custom development in C; everything is installed in the /opt/z-way-server  directory. There, one can find: A set of (documented, nice!) C header files found in /opt/z-way-server/libzway-dev : CommandClassesPublic.h FunctionClassesPublic.h ZDataPublic.h ZDefsPublic.h ZErrors.h ZPlatform.h ZWayLib.h A set of libraries found in /opt/z-way-server/libs : libmicrohttpd.so libv8.so libzwayhttp.so libzwayjs.so libzway.so For the ZWay stack to run properly, it is needed to provide the necessary configuration files. Instead of using these directly from the installation folder, I made a copy in order not to mess up too much with my working/configured setup. The following directories from the ZWay installation folder are needed: config translations ZDDX For experimenting I made a small Makefile in order to build and run. main.out: main.c gcc -I/opt/z-way-server/li
Read more

Libcurl: perform a REST HTTP PUT

The libcurl library does not provide a clear example on how to issue HTTP PUT operations in a REST context; the examples are mainly about file transfers . For my proxy application this is not really what I need: I want to perform a REST HTTP PUT, keep it simple, meaning without using the "Expect" and "Transfer-Encoding" that libcurl adds by default. After some struggling I discovered that this behavior can be changed by using the following code: CURL * pCurl; struct curl_slist *headers = NULL; headers = curl_slist_append(headers, "Content-Type: application/json "); headers = curl_slist_append(headers, "Content-Length: 12345 "); headers = curl_slist_append(headers, "Expect:"); headers = curl_slist_append(headers, "Transfer-Encoding:"); pCurl = curl_easy_init(); curl_easy_setopt(pCurl, CURLOPT_VERBOSE, 1); curl_easy_setopt(pCurl, CURLOPT_PUT, 1); curl_easy_setopt(pCurl, CURLOPT_URL, " https://your-server.app
Read more