channels

问题 I want to deploy my service to docker. and my service is developed using python+django and django-channels ── myproject ├── myproject │ ├── settings.py │ ├── urls.py │ ├── asgi.py │ ├── ... ├── collected_static │ ├── js │ ├── css │ ├── ... ├── nginx │ ├── Dockerfile │ ├── service.conf ├── requirements.txt ├── manage.py ├── Dockerfile └── docker-compose.yml myproject/Dockerfile : FROM python ENV PYTHONUNBURRERED 1 RUN mkdir -p /opt/myproject WORKDIR /opt/myproject ADD . /opt/myproject RUN pip

问题 I am using goroutines/channels. Here is my code. Why is the timeout case not getting executed? func main() { c1 := make(chan int, 1) go func() { for { time.Sleep(1500 * time.Millisecond) c1 <- 10 } }() go func() { for { select { case i := <-c1: fmt.Println(i) case <-time.After(2000 * time.Millisecond): fmt.Println("TIMEOUT") // <-- Not Executed } } }() fmt.Scanln() } 回答1: Your timeout doesn't happen, because one of your goroutine sends a value on your c1 channel in every 1.5 seconds (or so)

问题 I am using goroutines/channels. Here is my code. Why is the timeout case not getting executed? func main() { c1 := make(chan int, 1) go func() { for { time.Sleep(1500 * time.Millisecond) c1 <- 10 } }() go func() { for { select { case i := <-c1: fmt.Println(i) case <-time.After(2000 * time.Millisecond): fmt.Println("TIMEOUT") // <-- Not Executed } } }() fmt.Scanln() } 回答1: Your timeout doesn't happen, because one of your goroutine sends a value on your c1 channel in every 1.5 seconds (or so)

问题 I have a GeoTIFF image that contains a color table and a single raster band with 8-bit table keys, and that uses LZW compression, that I load with gdal.Open. I also have a numpy array containing 24-bit RGB-values (for a blurred version of the image), corresponding to three 8-bit raster bands. I need to substitute these three raster bands for the raster band that is currently in the image, and then save the image (preferably as a new file if possible). How do I do that? I would like to keep

问题 I am working on a Django Channels-2 project , where channel layer is used to offload information from browsers to a consumer who analyses it and send the results back to the Browsers via groups mechanism. The data comes from pusher via a pusher-client , and is therefore the same for many client browsers. My first took was to set-up the following infrastructure: layout 1: ( browser1: Pusher-client, websocket; ... browserN: Pusher-client, websocket) <----> WebsocketConsumer (member of group ;

问题 Is there a way to test for failure of a go channel send without actually attempting the send? The standard non-blocking send is like so: msg := "hi" select { case messages <- msg: fmt.Println("sent message", msg) default: fmt.Println("no message sent") } The problem is that I need to have "msg" ready to send in order to test the channel. I would like to test to see if a send will fail in a way that does not require having "msg" ready for sending. 回答1: That would do no good in the general case

问题 I am trying to implement websockets using channels in Django project. I am getting 404 for webscoketbridge.js Below is html template. {% load staticfiles %} {% block title %} Delivery {% endblock %} <link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.6/css/bootstrap.min.css"> <link href='https://fonts.googleapis.com/css?family=Satisfy' rel='stylesheet' type='text/css'> <script src="https://ajax.googleapis.com/ajax/libs/jquery/1.12.0/jquery.min.js"></script> <script src=

问题 Just experimenting with go recently. I was wondering what will happen if you have a select statement waiting for communication on a few channels and if a message comes AT THE SAME time on two or more channels. How will the select determine which channel to accept if all the messages come at the same time? Thanks! 回答1: From the spec: If multiple cases can proceed, a uniform pseudo-random choice is made to decide which single communication will execute. So the choice is non-deterministic. 来源：

问题 I'm currently trying to devise a scheme where the following happens. Client A is subscribed/connected to topic/channel T . A sends a message in the form of a select query to T . Only A receives the query results, no other subscribers. Is this even possible using Channels? The main reason I chose Channels was for the excellent websocket support - however I'm open to other Phoenix solutions. 回答1: Yes, Channels should do the work you want. You can push the query results down to the user who sent

问题 I've encountered a strange behaviour. I was playing around with buffered channels, and when using large buffers the whole program execution would block. In the following code snippet: package main import ( "fmt" ) func main() { choke := make(chan string, 150000) go func() { for i := 0; i < 10000000; i++ { choke <- string(i) fmt.Println("i=", i) } }() for { //fmt.Println(len(choke)) if len(choke) >= 150000 { fmt.Println("Full") } } } My program blocks at ~96000 iterations and never reaches the