App.WebNotificationComponent = Em.Component.extend
subscriptionQueue: null
connection: (->
App.StompConnection.create(subscriptionQueue: #get('subscriptionQueue'))
).property('subscriptionQueue')
willDestroy: ->
#get('connection').destroy()
App.AlertsIndexAlertWebNotificationComponent = App.WebNotificationComponent.extend
subscriptionQueue: "notifications"
didInsertElement: ->
#get('connection').onMessage = ((message) ->
result = JSON.parse(message.body)
App.AlertNotification.store.find('alert_notification', result.id).then (notification) =>
debugger
).bind(#get('targetObject'))
#get('connection').connect()
At the debugger breakpoint, I am no longer able to access message or result.
Is there anything that I am doing wrong or another way to do this ?
You can't access those values in the debugger because you didn't close over them, so they're not available in the closure. If you use them in the closure, they'll be available. Javascript has to know that you're going to use a variable in order to save it in the closed scope.
In other words, this will work as expected:
result = JSON.parse(message.body)
App.AlertNotification.store.find('alert_notification', result.id).then (notification) =>
console.log(message)
console.log(result)
Related
I have a simple rust program that interacts with a PostgreSQL database.
The actual code is:
for row in &db_client.query("select magic_value from priv.magic_value();", &[]).unwrap()
{
magic_value = row.get("magic_value");
println!("Magic value is = {}", magic_value);
}
And.. it works. But I don't like it: I know this function will return one and only one value.
From the example I found, for example here: https://docs.rs/postgres/latest/postgres/index.html
and here: https://tms-dev-blog.com/postgresql-database-with-rust-how-to/
You always have a recordset to loop on.
Which is the clean way to call a function without looping?
query returns a Result<Vec<Row>, _>. You are already unwrapping the Vec, so you can just use it directly instead of looping. By turning the Vec into an owning iterator yourself, you can even easily obtain a Row instead of a &Row.
magic_value = db_client.query("select magic_value from priv.magic_value();", &[])
.unwrap() // -> Vec<Row>
.into_iter() // -> impl Iterator<Item=Row>
.next() // -> Option<Row>
.unwrap() // -> Row
.get("magic_value");
Trying to test a binding of lit-html method html
open Jest;
let write = () => LitHtml.html("<div></div>");
open Expect;
describe("LitHtml", () =>
test("#html", () =>
expect(() =>
write()
) |> not_ |> toThrow
)
);
I am told this cryptic error:
Error: Unbound value not__
Hint: Did you mean not_?
Jest.Expect.plainPartial('a) => Jest.Expect.invertedPartial('a)
But clearly wrote not_ as it suggests, not not__.
My attempted binding:
[#bs.module "LitHtml"] [#bs.val]
external html: string => Js.nullable(string) = "html";
let html = htmlStr => html(htmlStr) |> Js.Nullable.toOption;
Thanks for any assistance. Just getting started with ReasonML ;)
Seems like this is caused by a largely undocumented change in Reason 3.3.4. I think it might hide in PR #2197.
not is a keyword in OCaml, which is why Expect.not_ is named such as it is in the first place. And this change seems to "mangle" (ie. translate) not in Reason into not_ in OCaml, and then not_ to not__ and so on.
So the solution is simply to replace all instances of not_ in your code with not. OR you can update bs-jest to 0.4.7 where I've added not__ as an alias to not_, so you can use either not or not_.
I am writing a simple app in Coffeescript to control a Philips Hue light. I have included this module into my project. The below code seems to work fine up until I try to set the color of the lights using setLightState. The compiler says the function isn't a function. I don't quite understand why it doesn't recognize the function.
# Connect with Philips Hue bridge
jsHue = require 'jshue'
hue = jsHue()
# Get the IP address of any bridges on the network
hueBridgeIPAddress = hue.discover().then((bridges) =>
if bridges.length is 0
console.log 'No bridges found. :('
else
(b.internalipaddress for b in bridges)
).catch((e) => console.log 'Error finding bridges', e)
if hueBridgeIPAddress.length isnt 0 # if there is at least 1 bridge
bridge = hue.bridge(hueBridgeIPAddress[0]) #get the first bridge in the list
# Create a user on that bridge (may need to press the reset button on the bridge before starting the tech buck)
user = bridge.createUser('myApp#testdevice').then((data) =>
username = data[0].success.username
console.log 'New username:', username
bridge.user(username)
)
if user?
#assuming a user was sucessfully created set the lighting to white
user.setLightState(1, {on:true, sat:0, bri:100, hue:65280}).then((data) =>
# process response data, do other things
)
As you can see on the github page of the jshue lib, bridge.createUser does not directly return a user object.
Instead the example code sets the user variable inside the then function of the returned promise:
bridge.createUser('myApp#testdevice').then(data => {
// extract bridge-generated username from returned data
var username = data[0].success.username;
// instantiate user object with username
var user = bridge.user(username);
user.setLightState( .... )
});
It can be expected that - using this approach - the user variable will be set correctly and user.setLightState will be defined.
A self-contained example:
Take this Codepen for example:
url = "https://api.ipify.org?format=json"
outside = axios.get(url).then (response) =>
inside = response.data.ip
console.log "inside: #{inside}"
inside
console.log "outside: #{outside}"
The console output is
outside: [object Promise]
inside: 178.19.212.102
You can see that:
the outside log is first and is a Promise object
the inside log comes last and contains the actual object from the Ajax call (in this case your IP)
the then function implicitly returning inside does not change anything
My code is as follows. I would expect the code inside configureMission() to finish running before running mapSurface. This does not appear to be happening.
missionCommands = "" # you don't have a mission yet
$('#startExploration').click -> # Set #missionControl as input for game configuration
configureMission()
mapSurface()
configureMission =->
$('#MissionControl').on "submit", ->
# cool helper function shamelessly pinched from http://jsfiddle.net/sxGtM/3/
$.fn.serializeObject = function() # not shown
missionCommands = JSON.stringify($('form').serializeObject())
return false #stops click event from firing
mapSurface =->
console.log('map')
console.log(missionCommands)
I have noticed that if I submit the form a second time, the missionCommands variable has been updated with the json data, so it appears that the form data has been processed, but that this is happening after the second function has run.
map login.js:60
login.js:61
map login.js:60
{"xMaximum":"","yMaximum":"","xCoord":["iuoiuyi",""],"yCoord":["",""],"orientaiton":["",""]} login.js:61
I can make it work by moving the mapSurface function inside the configureMission function, but this seems like bad form. I wonder, is there a more correct pattern I could use to achieve my desired result of processing the form data into json, setting this into a variable and passing the variable to a second function.
You're treating asynchronous commands as synchronous commands. JavaScript (and thereby CoffeeScript) works asynchronously, meaning that functions will be run in parallel.
You can solve this problem by specifying mapSurface() as the callback for configureMission() as follows:
missionCommands = ""
$('#startExploration').click ->
configureMission(mapSurface)
configureMission = (cb) ->
console.log "now running configureMission()"
$('#MissionControl').on "submit", ->
$.fn.serializeObject = function() # not shown
missionCommands = JSON.stringify($('form').serializeObject())
console.log "completed configureMission()"
return cb()
mapSurface = ->
console.log "now running mapSurface()"
console.log missionCommands
console.log "completed mapSurface()"
Learn about JavaScript callbacks here: http://recurial.com/programming/understanding-callback-functions-in-javascript/.
I have this class in which i try to initialize array attributes with query results:
class data
minute: []
hour: []
constructor: () ->
findMin = events.find({"aggr":"minute"}).sort({$natural:-1}).limit(120)
findHour = events.find({"aggr":"hour"}).sort({$natural:-1}).limit(14)
findMin.execFind (errMin, resMin) ->
for recMin in resMin
#minute.push recMin
findHour.execFind (errH, resH) ->
for recH in resH
#hour.push recH
So i call smth = new data() and console.log smth and get an empty attributes and an error about undefined not having 'push' method. While i can understand an error i cant get why my arrays are empty. Dont get me wrong - i know this error causes them to be empty, but i tried several kinds of variants. And ive read about acync and callbacks, but still don't have a clue how to use callbacks not to 'alert' smth, but to use it afterwards. If you could help me with that or with some links that could - i would appreciate it SO much.
You have two issues. The one that is causing the error you are observing is that '#' inside of your two callbacks is not bound to your data instance, so you need to use =>. Secondly, and as pointed out by #AaronDufour, your hour and minute arrays are declared at the class level so they will be shared between every instance of data, which I doubt is what you want, so you need to move them into your constructor.
class data
constructor: () ->
#minute = []
#hour = []
findMin = events.find({"aggr":"minute"}).sort({$natural:-1}).limit(120)
findHour = events.find({"aggr":"hour"}).sort({$natural:-1}).limit(14)
findMin.execFind (errMin, resMin) =>
for recMin in resMin
#minute.push recMin
findHour.execFind (errH, resH) =>
for recH in resH
#hour.push recH
I assume you want minute and hour to be instance variables? They must be initialized in the constructor. The way you're doing it now, they're on the prototype, so it won't work properly. Try this:
class data
constructor: () ->
#minute = []
#hour = []
findMin = events.find({"aggr":"minute"}).sort({$natural:-1}).limit(120)
findHour = events.find({"aggr":"hour"}).sort({$natural:-1}).limit(14)
findMin.execFind (errMin, resMin) =>
for recMin in resMin
#minute.push recMin
findHour.execFind (errH, resH) =>
for recH in resH
#hour.push recH