Enable using Chrome with WebSocket

Dockerfile

@@ -9,9 +9,9 @@ RUN CGO_ENABLED=0 GOOS=linux go build -o ./out/app .
 # Runtime image
 FROM alpine
 COPY --from=build /app/out/app /usr/local/bin/changemonitor
-RUN apk add --no-cache chromium
+RUN apk add --no-cache tzdata
 ENV CONFIG_FILE=/config/config.json
 ENV STORAGE_DIRECTORY=/data
-ENV CHROME_PATH=/usr/bin/chromium-browser
+ENV CHROME_WS=ws://127.0.0.1:9222
 ENV ENABLE_WEBUI=false
 ENTRYPOINT ["/usr/local/bin/changemonitor"]

Dockerfile.chrome

@@ -0,0 +1,17 @@
+# Build image
+FROM golang:alpine AS build
+WORKDIR /app
+COPY go.mod go.sum ./
+RUN go mod download
+COPY . ./
+RUN CGO_ENABLED=0 GOOS=linux go build -o ./out/app .
+
+# Runtime image
+FROM alpine
+COPY --from=build /app/out/app /usr/local/bin/changemonitor
+RUN apk add --no-cache tzdata chromium
+ENV CONFIG_FILE=/config/config.json
+ENV STORAGE_DIRECTORY=/data
+ENV CHROME_PATH=/usr/bin/chromium-browser
+ENV ENABLE_WEBUI=false
+ENTRYPOINT ["/usr/local/bin/changemonitor"]

html/html.go

@@ -5,6 +5,7 @@ import (
 	"html/template"
 	"io"
 	"net/http"
+	"strings"
 
 	"github.com/Ordspilleren/ChangeMonitor/monitor"
 )
@@ -20,6 +21,10 @@ var (
 	monitorNew  = parse("monitornew.html")
 )
 
+var funcs = template.FuncMap{
+	"StringsJoin": strings.Join,
+}
+
 type MonitorListParams struct {
 	MonitorService *monitor.MonitorService
 }
@@ -39,7 +44,7 @@ func MonitorNew(w io.Writer, p MonitorNewParams) error {
 
 func parse(file string) *template.Template {
 	return template.Must(
-		template.New("layout.html").ParseFS(htmlTemplates, "layout.html", file))
+		template.New("layout.html").Funcs(funcs).ParseFS(htmlTemplates, "layout.html", file))
 }
 
 func GetAssetFS() http.FileSystem {

html/monitornew.html

@@ -23,21 +23,21 @@
     <div class="field">
         <label class="label">Interval</label>
         <div class="control">
-            <input name="interval" class="input" type="number"{{if .Monitor}} value="{{.Monitor.Interval}}"{{end}}>
+            <input name="interval" class="input" type="number"{{if .Monitor}} value="{{.Monitor.Interval.Nanoseconds}}"{{end}}>
         </div>
     </div>
 
     <div class="field">
         <label class="label">CSS Selectors</label>
         <div class="control">
-            <textarea name="cssselectors" class="textarea"></textarea>
+            <textarea name="cssselectors" class="textarea">{{if .Monitor.Selectors.CSS}}{{StringsJoin .Monitor.Selectors.CSS "\n"}}{{end}}</textarea>
         </div>
     </div>
 
     <div class="field">
         <label class="label">JSON Selectors</label>
         <div class="control">
-            <textarea name="jsonselectors" class="textarea"></textarea>
+            <textarea name="jsonselectors" class="textarea">{{if .Monitor.Selectors.JSON}}{{StringsJoin .Monitor.Selectors.JSON "\n"}}{{end}}</textarea>
         </div>
     </div>
 

main.go

@@ -22,6 +22,7 @@ var wg = &sync.WaitGroup{}
 var ConfigFile string
 var StorageDirectory string
 var ChromePath string
+var ChromeWs string
 var EnableWebUI bool
 
 type Config struct {
@@ -43,6 +44,7 @@ func init() {
 	ConfigFile = getEnv("CONFIG_FILE", "config.json")
 	StorageDirectory = getEnv("STORAGE_DIRECTORY", "data")
 	ChromePath = getEnv("CHROME_PATH", "/usr/bin/chromium")
+	ChromeWs = getEnv("CHROME_WS", "")
 	EnableWebUI, _ = strconv.ParseBool(getEnv("ENABLE_WEBUI", "false"))
 	log.Printf("Config File: %s", ConfigFile)
 	log.Printf("Storage Directory: %s", StorageDirectory)
@@ -62,7 +64,11 @@ func init() {
 	storageManager := storage.InitStorage(StorageDirectory)
 
 	monitorService = monitor.NewMonitorService(wg, config.Monitors, storageManager, notifierService)
-	monitorService.NewMonitorClients(ChromePath)
+	if ChromeWs != "" {
+		monitorService.NewMonitorClients(ChromeWs, true)
+	} else {
+		monitorService.NewMonitorClients(ChromePath, false)
+	}
 	monitorService.InitMonitors()
 }
 

monitor/monitor.go

@@ -86,7 +86,7 @@ func NewMonitorService(wg *sync.WaitGroup, monitors Monitors, storage Storage, n
 	return &monitorService
 }
 
-func (ms *MonitorService) NewMonitorClients(chromePath string) error {
+func (ms *MonitorService) NewMonitorClients(chromePath string, externalClient bool) error {
 	var usingChrome bool
 
 	for _, monitor := range ms.Monitors {
@@ -97,7 +97,7 @@ func (ms *MonitorService) NewMonitorClients(chromePath string) error {
 	}
 
 	if usingChrome {
-		chromeClient, err := newChromeClient(chromePath)
+		chromeClient, err := newChromeClient(chromePath, externalClient)
 		if err != nil {
 			return fmt.Errorf("failed to create new chrome client: %v", err)
 		}
@@ -375,7 +375,11 @@ func (h ChromeClient) getHTTPBody(url string, headers http.Header) (io.ReadClose
 	return readCloser, nil
 }
 
-func newChromeClient(chromePath string) (*ChromeClient, error) {
+func newChromeClient(chromePath string, externalClient bool) (*ChromeClient, error) {
+	if externalClient {
+		return newExternalChromeClient(chromePath)
+	}
+
 	launcher := launcher.New().Bin(chromePath)
 	u, err := launcher.Launch()
 	if err != nil {
@@ -398,3 +402,21 @@ func newChromeClient(chromePath string) (*ChromeClient, error) {
 
 	return chromeClient, nil
 }
+
+func newExternalChromeClient(chromeWs string) (*ChromeClient, error) {
+	url, err := launcher.ResolveURL(chromeWs)
+	if err != nil {
+		return nil, fmt.Errorf("failed to connect to browser: %v", err)
+	}
+	browser := rod.New().ControlURL(url)
+	err = browser.Connect()
+	if err != nil {
+		return nil, fmt.Errorf("failed to connect to browser: %v", err)
+	}
+
+	chromeClient := &ChromeClient{
+		Browser: browser,
+	}
+
+	return chromeClient, nil
+}