feat(docs): add template preview (#1777)

pkg/notifications/preview/data/data.go

@@ -0,0 +1,143 @@
+package data
+
+import (
+	"encoding/hex"
+	"errors"
+	"math/rand"
+	"strconv"
+	"time"
+
+	"github.com/containrrr/watchtower/pkg/types"
+)
+
+type previewData struct {
+	rand           *rand.Rand
+	lastTime       time.Time
+	report         *report
+	containerCount int
+	Entries        []*logEntry
+	StaticData     staticData
+}
+
+type staticData struct {
+	Title string
+	Host  string
+}
+
+// New initializes a new preview data struct
+func New() *previewData {
+	return &previewData{
+		rand:           rand.New(rand.NewSource(1)),
+		lastTime:       time.Now().Add(-30 * time.Minute),
+		report:         nil,
+		containerCount: 0,
+		Entries:        []*logEntry{},
+		StaticData: staticData{
+			Title: "Title",
+			Host:  "Host",
+		},
+	}
+}
+
+// AddFromState adds a container status entry to the report with the given state
+func (pb *previewData) AddFromState(state State) {
+	cid := types.ContainerID(pb.generateID())
+	old := types.ImageID(pb.generateID())
+	new := types.ImageID(pb.generateID())
+	name := pb.generateName()
+	image := pb.generateImageName(name)
+	var err error
+	if state == FailedState {
+		err = errors.New(pb.randomEntry(errorMessages))
+	} else if state == SkippedState {
+		err = errors.New(pb.randomEntry(skippedMessages))
+	}
+	pb.addContainer(containerStatus{
+		containerID:   cid,
+		oldImage:      old,
+		newImage:      new,
+		containerName: name,
+		imageName:     image,
+		error:         err,
+		state:         state,
+	})
+}
+
+func (pb *previewData) addContainer(c containerStatus) {
+	if pb.report == nil {
+		pb.report = &report{}
+	}
+	switch c.state {
+	case ScannedState:
+		pb.report.scanned = append(pb.report.scanned, &c)
+	case UpdatedState:
+		pb.report.updated = append(pb.report.updated, &c)
+	case FailedState:
+		pb.report.failed = append(pb.report.failed, &c)
+	case SkippedState:
+		pb.report.skipped = append(pb.report.skipped, &c)
+	case StaleState:
+		pb.report.stale = append(pb.report.stale, &c)
+	case FreshState:
+		pb.report.fresh = append(pb.report.fresh, &c)
+	default:
+		return
+	}
+	pb.containerCount += 1
+}
+
+// AddLogEntry adds a preview log entry of the given level
+func (pd *previewData) AddLogEntry(level LogLevel) {
+	var msg string
+	switch level {
+	case FatalLevel:
+		fallthrough
+	case ErrorLevel:
+		fallthrough
+	case WarnLevel:
+		msg = pd.randomEntry(logErrors)
+	default:
+		msg = pd.randomEntry(logMessages)
+	}
+	pd.Entries = append(pd.Entries, &logEntry{
+		Message: msg,
+		Data:    map[string]any{},
+		Time:    pd.generateTime(),
+		Level:   level,
+	})
+}
+
+// Report returns a preview report
+func (pb *previewData) Report() types.Report {
+	return pb.report
+}
+
+func (pb *previewData) generateID() string {
+	buf := make([]byte, 32)
+	_, _ = pb.rand.Read(buf)
+	return hex.EncodeToString(buf)
+}
+
+func (pb *previewData) generateTime() time.Time {
+	pb.lastTime = pb.lastTime.Add(time.Duration(pb.rand.Intn(30)) * time.Second)
+	return pb.lastTime
+}
+
+func (pb *previewData) randomEntry(arr []string) string {
+	return arr[pb.rand.Intn(len(arr))]
+}
+
+func (pb *previewData) generateName() string {
+	index := pb.containerCount
+	if index <= len(containerNames) {
+		return "/" + containerNames[index]
+	}
+	suffix := index / len(containerNames)
+	index %= len(containerNames)
+	return "/" + containerNames[index] + strconv.FormatInt(int64(suffix), 10)
+}
+
+func (pb *previewData) generateImageName(name string) string {
+	index := pb.containerCount % len(organizationNames)
+	return organizationNames[index] + name + ":latest"
+}