adding test containers

haven-notify/templates.go

@@ -0,0 +1,135 @@
+package main
+
+import (
+	"bytes"
+	"embed"
+	"encoding/json"
+	"fmt"
+	"io/fs"
+	"strconv"
+	"text/template"
+)
+
+//go:embed template/*.tmpl
+var templatesFS embed.FS
+
+type templateRenderer struct {
+	templates map[string]*template.Template
+}
+
+type templateExtra struct {
+	Name  string
+	Value string
+}
+
+type backupTemplateData struct {
+	Title          string
+	Asset          string
+	BackupSizeInMB float64
+	Extra          []templateExtra
+}
+
+type updateTemplateData struct {
+	Host  string
+	Asset string
+	Time  float64
+}
+
+type errorTemplateData struct {
+	Caller   string
+	Message  string
+	Critical bool
+	Extra    []templateExtra
+}
+
+func newTemplateRenderer() (*templateRenderer, error) {
+	return newTemplateRendererFromFS(templatesFS)
+}
+
+func newTemplateRendererFromFS(templateFS fs.FS) (*templateRenderer, error) {
+	functions := template.FuncMap{
+		"formatSize":    formatSize,
+		"formatSeconds": formatSeconds,
+		"json":          jsonLiteral,
+	}
+	templates := make(map[string]*template.Template, 3)
+	for _, name := range []string{"backup", "update", "error"} {
+		contents, err := fs.ReadFile(templateFS, "template/"+name+".tmpl")
+		if err != nil {
+			return nil, err
+		}
+		parsed, err := template.New(name).Funcs(functions).Parse(string(contents))
+		if err != nil {
+			return nil, err
+		}
+		templates[name] = parsed
+	}
+	return &templateRenderer{templates: templates}, nil
+}
+
+func (r *templateRenderer) renderBackup(request backupRequest) (discordPayload, error) {
+	return r.render("backup", backupTemplateData{
+		Title:          *request.Title,
+		Asset:          *request.Asset,
+		BackupSizeInMB: *request.BackupSizeInMB,
+		Extra:          templateExtras(request.Extra),
+	})
+}
+
+func (r *templateRenderer) renderUpdate(request updateRequest) (discordPayload, error) {
+	return r.render("update", updateTemplateData{
+		Host:  *request.Host,
+		Asset: *request.Asset,
+		Time:  *request.Time,
+	})
+}
+
+func (r *templateRenderer) renderError(request errorRequest) (discordPayload, error) {
+	return r.render("error", errorTemplateData{
+		Caller:   *request.Caller,
+		Message:  *request.Message,
+		Critical: *request.Critical,
+		Extra:    templateExtras(request.Extra),
+	})
+}
+
+func (r *templateRenderer) render(name string, data any) (discordPayload, error) {
+	parsed, ok := r.templates[name]
+	if !ok {
+		return discordPayload{}, fmt.Errorf("unknown template %q", name)
+	}
+	var rendered bytes.Buffer
+	if err := parsed.Execute(&rendered, data); err != nil {
+		return discordPayload{}, err
+	}
+	var payload discordPayload
+	if err := json.Unmarshal(rendered.Bytes(), &payload); err != nil {
+		return discordPayload{}, fmt.Errorf("template produced invalid JSON: %w", err)
+	}
+	normalizeDiscordPayload(&payload)
+	return payload, nil
+}
+
+func templateExtras(extra extraRequests) []templateExtra {
+	result := make([]templateExtra, 0, len(extra))
+	for _, field := range extra {
+		result = append(result, templateExtra{Name: *field.Name, Value: *field.Value})
+	}
+	return result
+}
+
+func jsonLiteral(value any) (string, error) {
+	encoded, err := json.Marshal(value)
+	return string(encoded), err
+}
+
+func formatSize(size float64) string {
+	if size >= 1024 {
+		return fmt.Sprintf("%.2f GiB", size/1024)
+	}
+	return fmt.Sprintf("%.2f MiB", size)
+}
+
+func formatSeconds(seconds float64) string {
+	return strconv.FormatFloat(seconds, 'f', -1, 64) + " seconds"
+}