107 lines
1.8 KiB
Markdown
107 lines
1.8 KiB
Markdown
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# What
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Database changes notification library.
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### Example
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```go
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package main
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import (
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"encoding/json"
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"log"
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"net/http"
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"git.icod.de/dalu/notifier"
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"github.com/gin-gonic/gin"
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"gopkg.in/olahol/melody.v1"
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)
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func main() {
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r := gin.Default()
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m := melody.New()
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n := notifier.NewNotifier(m)
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h := NewHandler(n)
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r.GET("/", h.Index)
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r.GET("/ws", func(cx *gin.Context) {
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m.HandleRequest(cx.Writer, cx.Request)
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})
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r.GET("/acme/ins", h.InsertDB)
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go n.Listen(func(notification *notifier.Notification) {
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b, e := json.Marshal(notification)
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if e != nil {
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log.Println(e.Error())
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return
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}
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m.Broadcast(b)
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})
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r.Run(":5000")
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}
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type Handler struct {
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notifier *notifier.Notifier
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}
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func NewHandler(n *notifier.Notifier) *Handler {
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h := new(Handler)
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h.notifier = n
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return h
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}
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func (h *Handler) Index(cx *gin.Context) {
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http.ServeFile(cx.Writer, cx.Request, "index.html")
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}
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func (h *Handler) InsertDB(cx *gin.Context) {
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// Do database insert stuff
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h.notifier.Notify("acme", "INSERT", []byte(`{"id": 1, "name": acme}`))
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cx.JSON(201, map[string]interface{}{"status": "ok"})
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}
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```
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```html
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<html>
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<head>
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<title>Melody example: chatting</title>
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</head>
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<style>
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#chat {
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text-align: left;
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background: #f1f1f1;
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width: 500px;
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min-height: 300px;
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padding: 20px;
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}
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</style>
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<body>
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<div align="center">
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<h3>Chat</h3>
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<pre id="chat"></pre>
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</div>
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<script>
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let url = "ws://localhost:5000/ws";
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let ws = new WebSocket(url);
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let chat = document.getElementById("chat");
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let now = function () {
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let iso = new Date().toISOString();
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return iso.split("T")[1].split(".")[0];
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};
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ws.onmessage = function (msg) {
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let line = now() + " " + msg.data + "\n";
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chat.innerText += line;
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};
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</script>
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</body>
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</html>
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```
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