diff --git a/api/streamlogs.go b/api/streamlogs.go
new file mode 100644
index 0000000..cdd9143
--- /dev/null
+++ b/api/streamlogs.go
@@ -0,0 +1,174 @@
+package api
+
+import (
+ "io/ioutil"
+ "log"
+ "net/http"
+ "os"
+ "strconv"
+ "text/template"
+ "time"
+
+ "github.com/gorilla/websocket"
+)
+
+const (
+ // Time allowed to write the file to the client.
+ writeWait = 10 * time.Second
+
+ // Time allowed to read the next pong message from the client.
+ pongWait = 60 * time.Second
+
+ // Send pings to client with this period. Must be less than pongWait.
+ pingPeriod = (pongWait * 9) / 10
+
+ // Poll file for changes with this period.
+ filePeriod = 10 * time.Second
+)
+
+var (
+ homeTempl = template.Must(template.New("").Parse(homeHTML))
+ filename = "/var/lib/docker/containers/1967dededef67f90df186c7569ccfa5d7d6828447bd47c4c48657c837990943a/1967dededef67f90df186c7569ccfa5d7d6828447bd47c4c48657c837990943a-json.log"
+ upgrader = websocket.Upgrader{
+ ReadBufferSize: 1024,
+ WriteBufferSize: 1024,
+ }
+)
+
+func readFileIfModified(lastMod time.Time) ([]byte, time.Time, error) {
+ fi, err := os.Stat(filename)
+ if err != nil {
+ return nil, lastMod, err
+ }
+ if !fi.ModTime().After(lastMod) {
+ return nil, lastMod, nil
+ }
+ p, err := ioutil.ReadFile(filename)
+ if err != nil {
+ return nil, fi.ModTime(), err
+ }
+ return p, fi.ModTime(), nil
+}
+
+func reader(ws *websocket.Conn) {
+ defer ws.Close()
+ ws.SetReadLimit(512)
+ ws.SetReadDeadline(time.Now().Add(pongWait))
+ ws.SetPongHandler(func(string) error { ws.SetReadDeadline(time.Now().Add(pongWait)); return nil })
+ for {
+ _, _, err := ws.ReadMessage()
+ if err != nil {
+ break
+ }
+ }
+}
+
+func writer(ws *websocket.Conn, lastMod time.Time) {
+ lastError := ""
+ pingTicker := time.NewTicker(pingPeriod)
+ fileTicker := time.NewTicker(filePeriod)
+ defer func() {
+ pingTicker.Stop()
+ fileTicker.Stop()
+ ws.Close()
+ }()
+ for {
+ select {
+ case <-fileTicker.C:
+ var p []byte
+ var err error
+
+ p, lastMod, err = readFileIfModified(lastMod)
+
+ if err != nil {
+ if s := err.Error(); s != lastError {
+ lastError = s
+ p = []byte(lastError)
+ }
+ } else {
+ lastError = ""
+ }
+
+ if p != nil {
+ ws.SetWriteDeadline(time.Now().Add(writeWait))
+ if err := ws.WriteMessage(websocket.TextMessage, p); err != nil {
+ return
+ }
+ }
+ case <-pingTicker.C:
+ ws.SetWriteDeadline(time.Now().Add(writeWait))
+ if err := ws.WriteMessage(websocket.PingMessage, []byte{}); err != nil {
+ return
+ }
+ }
+ }
+}
+
+func StreamLogs(w http.ResponseWriter, r *http.Request) {
+ ws, err := upgrader.Upgrade(w, r, nil)
+ if err != nil {
+ if _, ok := err.(websocket.HandshakeError); !ok {
+ log.Println(err)
+ }
+ return
+ }
+
+ var lastMod time.Time
+ if n, err := strconv.ParseInt(r.FormValue("lastMod"), 16, 64); err == nil {
+ lastMod = time.Unix(0, n)
+ }
+
+ go writer(ws, lastMod)
+ reader(ws)
+}
+
+func Logs(w http.ResponseWriter, r *http.Request) {
+ if r.URL.Path != "/logs" {
+ http.Error(w, "Not found", http.StatusNotFound)
+ return
+ }
+ if r.Method != "GET" {
+ http.Error(w, "Method not allowed", http.StatusMethodNotAllowed)
+ return
+ }
+ w.Header().Set("Content-Type", "text/html; charset=utf-8")
+ p, lastMod, err := readFileIfModified(time.Time{})
+ if err != nil {
+ p = []byte(err.Error())
+ lastMod = time.Unix(0, 0)
+ }
+ var v = struct {
+ Host string
+ Data string
+ LastMod string
+ }{
+ r.Host,
+ string(p),
+ strconv.FormatInt(lastMod.UnixNano(), 16),
+ }
+ homeTempl.Execute(w, &v)
+}
+
+const homeHTML = `
+
+
+ WebSocket Example
+
+
+ {{.Data}}
+
+
+
+`
diff --git a/go.mod b/go.mod
index 5fa89ef..0dedd5e 100644
--- a/go.mod
+++ b/go.mod
@@ -6,9 +6,9 @@ require (
github.com/cloudflare/cloudflare-go v0.14.0
github.com/golang/gddo v0.0.0-20210115222349-20d68f94ee1f
github.com/google/go-cmp v0.5.1 // indirect
- github.com/gorilla/websocket v1.4.2 // indirect
- github.com/rs/cors v1.8.0 // indirect
+ github.com/gorilla/websocket v1.4.2
+ github.com/rs/cors v1.8.0
golang.org/x/time v0.0.0-20210220033141-f8bda1e9f3ba // indirect
golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1 // indirect
- gopkg.in/yaml.v3 v3.0.0-20210107192922-496545a6307b // indirect
+ gopkg.in/yaml.v3 v3.0.0-20210107192922-496545a6307b
)
diff --git a/main.go b/main.go
index 81ebeb6..b813ac0 100644
--- a/main.go
+++ b/main.go
@@ -16,6 +16,8 @@ func main() {
mux.HandleFunc("/hello", api.Hello)
mux.HandleFunc("/createservice", api.CreateService)
mux.HandleFunc("/githubAuth", api.GithubAuth)
+ mux.HandleFunc("/logs", api.Logs)
+ mux.HandleFunc("/streamlogs", api.StreamLogs)
// TODO: remove http version
c := cors.New(cors.Options{
AllowedOrigins: []string{"https://spinup.host", "http://spinup.host"},