feat: adds the ability to show a specific log from the past with a permanent link (#3958)

internal/web/logs.go

@@ -4,6 +4,7 @@ import (
 	"compress/gzip"
 	"context"
 	"errors"
+	"math"
 	"regexp"
 	"sort"
 	"strconv"
@@ -62,7 +63,6 @@ func (h *handler) fetchLogsBetweenDates(w http.ResponseWriter, r *http.Request)
 		return
 	}
 
-	buffer := utils.NewRingBuffer[*container.LogEvent](500)
 	delta := max(to.Sub(from), time.Second*3)
 
 	var regex *regexp.Regexp
@@ -82,8 +82,9 @@ func (h *handler) fetchLogsBetweenDates(w http.ResponseWriter, r *http.Request)
 	}
 
 	minimum := 0
-	if r.URL.Query().Has("minimum") {
-		minimum, err = strconv.Atoi(r.URL.Query().Get("minimum"))
+	buffer := utils.NewRingBuffer[*container.LogEvent](500)
+	if r.URL.Query().Has("min") {
+		minimum, err = strconv.Atoi(r.URL.Query().Get("min"))
 		if err != nil {
 			http.Error(w, err.Error(), http.StatusBadRequest)
 			return
@@ -93,6 +94,21 @@ func (h *handler) fetchLogsBetweenDates(w http.ResponseWriter, r *http.Request)
 			http.Error(w, errors.New("minimum must be between 0 and buffer size").Error(), http.StatusBadRequest)
 			return
 		}
+		buffer = utils.NewRingBuffer[*container.LogEvent](minimum)
+	}
+
+	maxStart := math.MaxInt
+	if r.URL.Query().Has("maxStart") {
+		maxStart, err = strconv.Atoi(r.URL.Query().Get("maxStart"))
+		if err != nil {
+			http.Error(w, err.Error(), http.StatusBadRequest)
+			return
+		}
+
+		if maxStart < 1 || maxStart > buffer.Size {
+			http.Error(w, errors.New("invalid maxStart").Error(), http.StatusBadRequest)
+			return
+		}
 	}
 
 	levels := make(map[string]struct{})
@@ -120,7 +136,7 @@ func (h *handler) fetchLogsBetweenDates(w http.ResponseWriter, r *http.Request)
 	}
 
 	for {
-		if buffer.Len() > minimum {
+		if minimum > 0 && buffer.Len() >= minimum {
 			break
 		}
 
@@ -157,6 +173,10 @@ func (h *handler) fetchLogsBetweenDates(w http.ResponseWriter, r *http.Request)
 					break
 				}
 
+				if buffer.Len() >= maxStart {
+					break
+				}
+
 				support_web.EscapeHTMLValues(event)
 				buffer.Push(event)
 			}
@@ -166,13 +186,19 @@ func (h *handler) fetchLogsBetweenDates(w http.ResponseWriter, r *http.Request)
 			break
 		}
 
+		if minimum == 0 {
+			break
+		}
+
 		from = from.Add(-delta)
 		delta = delta * 2
 	}
 
 	log.Debug().Int("buffer_size", buffer.Len()).Msg("sending logs to client")
 
-	for _, event := range buffer.Data() {
+	data := buffer.Data()
+
+	for _, event := range data {
 		if err := encoder.Encode(event); err != nil {
 			log.Error().Err(err).Msg("error encoding log event")
 			return

internal/web/logs_test.go

@@ -268,6 +268,7 @@ func Test_handler_between_dates_with_fill(t *testing.T) {
 	q.Add("stderr", "true")
 	q.Add("fill", "true")
 	q.Add("levels", "info")
+	q.Add("min", "10")
 
 	req.URL.RawQuery = q.Encode()
 
@@ -280,16 +281,22 @@ func Test_handler_between_dates_with_fill(t *testing.T) {
 	mockedClient.On("ContainerLogsBetweenDates", mock.Anything, id, from, to, container.STDALL).
 		Return(io.NopCloser(bytes.NewReader([]byte{})), nil).
 		Once()
+
 	mockedClient.On("ContainerLogsBetweenDates", mock.Anything, id, time.Date(2017, time.December, 31, 14, 0, 0, 0, time.UTC), to, container.STDALL).
 		Return(io.NopCloser(bytes.NewReader(data)), nil).
 		Once()
-	mockedClient.On("FindContainer", mock.Anything, id).Return(container.Container{ID: id}, nil)
-	mockedClient.On("Host").Return(container.Host{
-		ID: "localhost",
-	})
+
+	mockedClient.On("ContainerLogsBetweenDates", mock.Anything, id, time.Date(2017, time.December, 30, 18, 0, 0, 0, time.UTC), to, container.STDALL).
+		Return(io.NopCloser(bytes.NewReader(data)), nil).
+		Once()
+
+	mockedClient.On("FindContainer", mock.Anything, id).Return(container.Container{ID: id, Created: time.Date(2017, time.December, 31, 10, 0, 0, 0, time.UTC)}, nil)
+	mockedClient.On("Host").Return(container.Host{ID: "localhost"})
+
 	mockedClient.On("ListContainers", mock.Anything, mock.Anything).Return([]container.Container{
 		{ID: id, Name: "test", Host: "localhost", State: "running"},
 	}, nil)
+
 	mockedClient.On("ContainerEvents", mock.Anything, mock.AnythingOfType("chan<- container.ContainerEvent")).Return(nil)
 
 	handler := createDefaultHandler(mockedClient)