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diff --git a/vendor/github.com/gorilla/websocket/examples/chat/README.md b/vendor/github.com/gorilla/websocket/examples/chat/README.md deleted file mode 100644 index 7baf3e328..000000000 --- a/vendor/github.com/gorilla/websocket/examples/chat/README.md +++ /dev/null @@ -1,102 +0,0 @@ -# Chat Example - -This application shows how to use the -[websocket](https://github.com/gorilla/websocket) package to implement a simple -web chat application. - -## Running the example - -The example requires a working Go development environment. The [Getting -Started](http://golang.org/doc/install) page describes how to install the -development environment. - -Once you have Go up and running, you can download, build and run the example -using the following commands. - - $ go get github.com/gorilla/websocket - $ cd `go list -f '{{.Dir}}' github.com/gorilla/websocket/examples/chat` - $ go run *.go - -To use the chat example, open http://localhost:8080/ in your browser. - -## Server - -The server application defines two types, `Client` and `Hub`. The server -creates an instance of the `Client` type for each websocket connection. A -`Client` acts as an intermediary between the websocket connection and a single -instance of the `Hub` type. The `Hub` maintains a set of registered clients and -broadcasts messages to the clients. - -The application runs one goroutine for the `Hub` and two goroutines for each -`Client`. The goroutines communicate with each other using channels. The `Hub` -has channels for registering clients, unregistering clients and broadcasting -messages. A `Client` has a buffered channel of outbound messages. One of the -client's goroutines reads messages from this channel and writes the messages to -the websocket. The other client goroutine reads messages from the websocket and -sends them to the hub. - -### Hub - -The code for the `Hub` type is in -[hub.go](https://github.com/gorilla/websocket/blob/master/examples/chat/hub.go). -The application's `main` function starts the hub's `run` method as a goroutine. -Clients send requests to the hub using the `register`, `unregister` and -`broadcast` channels. - -The hub registers clients by adding the client pointer as a key in the -`clients` map. The map value is always true. - -The unregister code is a little more complicated. In addition to deleting the -client pointer from the `clients` map, the hub closes the clients's `send` -channel to signal the client that no more messages will be sent to the client. - -The hub handles messages by looping over the registered clients and sending the -message to the client's `send` channel. If the client's `send` buffer is full, -then the hub assumes that the client is dead or stuck. In this case, the hub -unregisters the client and closes the websocket. - -### Client - -The code for the `Client` type is in [client.go](https://github.com/gorilla/websocket/blob/master/examples/chat/client.go). - -The `serveWs` function is registered by the application's `main` function as -an HTTP handler. The handler upgrades the HTTP connection to the WebSocket -protocol, creates a client, registers the client with the hub and schedules the -client to be unregistered using a defer statement. - -Next, the HTTP handler starts the client's `writePump` method as a goroutine. -This method transfers messages from the client's send channel to the websocket -connection. The writer method exits when the channel is closed by the hub or -there's an error writing to the websocket connection. - -Finally, the HTTP handler calls the client's `readPump` method. This method -transfers inbound messages from the websocket to the hub. - -WebSocket connections [support one concurrent reader and one concurrent -writer](https://godoc.org/github.com/gorilla/websocket#hdr-Concurrency). The -application ensures that these concurrency requirements are met by executing -all reads from the `readPump` goroutine and all writes from the `writePump` -goroutine. - -To improve efficiency under high load, the `writePump` function coalesces -pending chat messages in the `send` channel to a single WebSocket message. This -reduces the number of system calls and the amount of data sent over the -network. - -## Frontend - -The frontend code is in [home.html](https://github.com/gorilla/websocket/blob/master/examples/chat/home.html). - -On document load, the script checks for websocket functionality in the browser. -If websocket functionality is available, then the script opens a connection to -the server and registers a callback to handle messages from the server. The -callback appends the message to the chat log using the appendLog function. - -To allow the user to manually scroll through the chat log without interruption -from new messages, the `appendLog` function checks the scroll position before -adding new content. If the chat log is scrolled to the bottom, then the -function scrolls new content into view after adding the content. Otherwise, the -scroll position is not changed. - -The form handler writes the user input to the websocket and clears the input -field. |