in node.js I am using for loop on server.js but it is not working and cause error
var myEasyrtcApp = function(err, appObj) {
for (i = 0; i < 10; i++) {
appObj.createRoom("room" + i ,null,function(err, roomObj){});
};
}
Please advice how can I use for loop to call appObj.createRoom several time to open different conference room
Sorry, but you almost not give any information... Asuming the last function is a Callback you need to make a Recursive "Loop" something like:
http://pastebin.com/LrKqLgyV
And to use it you can do this:
http://pastebin.com/L1bZZis0
To learn more about this, just google "recursive functions". (I can't post more than 2 links XD)
Hope It works for you ;)
Related
How can you detect if any sounds are playing in soundJS?
I have lots of sounds firing on and off sometimes legitimately over the top of each other. I need a way to find out if any sounds are playing at any given time
ie. something like
createjs.Sound.isPlaying()
or
createjs.Sound.status()
Nothing exists like this in SoundJS currently.
You can look it up yourself, but it involves digging into private members, which is not recommended, and could break content down the road. Here is a quick sample:
function countActiveSounds() {
var s = createjs.Sound.activePlugin,
count = 0;
for (var n in s._soundInstances) {
var inst = s._soundInstances[n];
for (var i=0, l=inst.length; i<l; i++) {
var p = inst[i];
if (p.playState == "playSucceeded") { count++; }
}
}
return count;
}
This involves reading the private _soundInstances hash, and checking if the sound state is "playSucceeded". Once it is complete, the state will changed to "playFinished".
Again, use this with caution :)
It might make sense to log a feature request to the SoundJS GitHub.
I'm fairly new at all this but have muddled my way to getting my Arduino to post values to a Xively stream I've named "Lux and Temp." Three values; count, lux, and temperature.
Now what I want to do is take those values and do something with them using Node-Red.
http://nodered.org
I have Node-Red up and running, but I'll be danged if I can figure out how to parse the data from the Xively API feed. https://api.xively.com/v2/feeds/1823833592
Sadly, I don't have enough reputation points to be able to actually post the data it returns to here, since it has more than 3 URLs embedded in the data. It's a LONG string of data too. ;)
I'm just stumped though as to how to write the function to extract the parts I want.
My initial want is to make a simple Twitter feed out of it. Something like;
"Count 40, Lux 30, Temp 78.3"
I'll eventually want to recycle the code for other things like making my RasPi do something; maybe a display or some LEDs. In either case I need to parse the data and build various messages with it.
Anybody have any experience with the Node-Red functions that can walk me through a solution? The Node-Red site is pretty awesome, but I think it assumes I'm a MUCH more experienced user than I really am. It gives hints, but frankly about all I know is fairly basic Arduino and trivial level Python.
OK, it shouldn't be too tricky, but try putting this in a function block:
var newPayload = "";
var count, lux, temp;
var data = msg.payload.datastreams;
for (var i = 0 ; i< data.length; i++) {
if (data[i].id === 'Count') {
count = data[i].current_value;
}else if (data[i].id === 'Lux') {
lux = data[i].current_value;
} else if (data[i].id === 'Temp') {
temp = data[i].current_value;
}
}
newPayload = util.format('Count: %s, Lux: %s, Temp: %s', count, lux, temp);
msg.payload = newPayload;
return msg;
You may need to add a msg.payload = JSON.parse(msg.payload); to the start if however your getting the feed from xively is not already considered to be json.
[edit]
You could also just run the flow through a JSON parse node. (I always forget the converter nodes)
You should be able to wire that to a twitter output node.
is the spotify models.Track object restricted to non-local tracks only?
I've built a little spotify app that will calculate the total play time of some random assortment of tracks that are dropped into the sidebar, but it seems like the Track object doesn't get any information from local files.
Here's what I got so far:
models.application.observe(models.EVENT.LINKSCHANGED, function () {
totalTime = 0;
var links = models.application.links;
if (links.length) {
for (var i = 0; i < links.length; i++) {
var track = models.Track.fromURI(links[i], function(t) {
totalTime = totalTime + t.duration;
});
}
}
document.getElementById("time").innerHTML = secondsToString(Math.round(totalTime/1000)) ;
});
Everything is firing correctly and working great on spotify tracks, but the whole reason i wrote this little app was so that I could calculate the total time of some of my really long audiobook files. Anyone know of a solution?
Link to the documentation page.
If this is indeed the case, I think you've found a bug/oversight.
However, local file URIs look like this: spotify:local:Coldplay:Mylo+Xyloto:Paradise:277
That last parameter is the length of the track, in integral seconds. It's a hacky workaround, but you could parse the URI and use the figure from that instead of models.Track.
I need to be able to make retries in node.js in the event of failure inside a function. I've setup a while loop as shown below, but I am getting slightly confused about how I should wrap the function call to not make sure that it won't block my whole server.
What should I do?
while(retryCount < 10 && !success){
// Alternative one
while(new Date().getTime() < now + 1000) {
myFunction();
}
// Or:
setTimeout( myFunction(), 1000);
}
You can store number of tryes in function object. It's will be fine for cronjob. If you need same behaviour in request context you must store attempts counter in request scope (not in function object).
var fnc = function() {
console.log('try');
if (true) { // Error condition
// Error here
if (!fnc.tryes) fnc.tryes = 0;
fnc.tryes++;
console.log(fnc.tryes);
if (fnc.tryes <= 10) {
setTimeout(fnc, 1000);
} else {
fnc.tryes = 0;
}
// Something wrong
} else {
// We hame result
}
};
fnc();
I'd say use the setTimeout method, that way the client won't be stuck inside the while loop that checks the time.
That outer while loop is going to block, you'd have to refactor using only setTimeout. However, the fact that you want this sort of thing indicates to me that your code structure is really terrible and needs more reworking. What is it that you are retrying? How are you detecting an error condition? Does doing it 10 times really make the chances of success higher?
I have a gist containing a generic function that will do this sort of thing for you, but I'm reluctant to share if this is an XY problem.
I believe this is related to the asynchronous nature of chrome extensions.
This section of my code:
alert(tab.title);
chrome.tabs.executeScript(tab.id, {code:"document.title = 'test'"});
Works fine, but as soon as I remove the alert, it stops working. Is there anything I can do to remove the alert but still have the js injected?
EDIT: More Code
tabs is a global array of tab objects.
chrome.tabs.onSelectionChanged.addListener(function (tabId) {
for (var i = 0; i < tabs.length; i++) {
if (tabs[i].id == tabId) {
var tab = tabs[i];
while (i < tabs.length) {//length-1
tabs[i] = tabs[i+1];
i++;
}
tabs.pop();
alert(tab.title);//WHY IS THIS NEEDED
chrome.tabs.executeScript(tab.id, {code:"document.title = document.title.substring(1)"});
return;
}
}
});
I am very confused. Changing it the following solves the problem:
chrome.tabs.executeScript(tab.id, {code:"setTimeout('document.title = document.title.substring(1)',100)"});
However, as soon as I change the delay to 50, the script doesn't get executed again. I would prefer not to have to have to make this delay. Does anyone know whats going on?
I know this is an old question, but if anyone is looking - wrap the chrome.tabs.executeScript method in a timeout.
setTimeout(function(){chrome.tabs.executeScript(tab.id, {code:"setTimeout('document.title = document.title.substring(1)',100)"});},500);
It's certainly not ideal but it gets the job done.
Sounds like you have a race condition. My best guess would be to change the injected code to execute on onLoad.