feat: text/mustacheutil: init

go.mod

@@ -8,6 +8,7 @@ require (
 	github.com/aws/aws-sdk-go v1.55.5
 	github.com/buaazp/fasthttprouter v0.1.1
 	github.com/buger/jsonparser v1.1.1
+	github.com/cbroglie/mustache v1.4.0
 	github.com/derekstavis/go-qs v0.0.0-20180720192143-9eef69e6c4e7
 	github.com/emersion/go-imap v1.2.1
 	github.com/go-logfmt/logfmt v0.6.0

go.sum

@@ -16,6 +16,8 @@ github.com/buger/jsonparser v1.1.1 h1:2PnMjfWD7wBILjqQbt530v576A/cAbQvEW9gGIpYMU
 github.com/buger/jsonparser v1.1.1/go.mod h1:6RYKKt7H4d4+iWqouImQ9R2FZql3VbhNgx27UK13J/0=
 github.com/caarlos0/env/v11 v11.3.1 h1:cArPWC15hWmEt+gWk7YBi7lEXTXCvpaSdCiZE2X5mCA=
 github.com/caarlos0/env/v11 v11.3.1/go.mod h1:qupehSf/Y0TUTsxKywqRt/vJjN5nz6vauiYEUUr8P4U=
+github.com/cbroglie/mustache v1.4.0 h1:Azg0dVhxTml5me+7PsZ7WPrQq1Gkf3WApcHMjMprYoU=
+github.com/cbroglie/mustache v1.4.0/go.mod h1:SS1FTIghy0sjse4DUVGV1k/40B1qE1XkD9DtDsHo9iM=
 github.com/cespare/xxhash/v2 v2.3.0 h1:UL815xU9SqsFlibzuggzjXhog7bL6oX9BbNZnL2UFvs=
 github.com/cespare/xxhash/v2 v2.3.0/go.mod h1:VGX0DQ3Q6kWi7AoAeZDth3/j3BFtOZR5XLFGgcrjCOs=
 github.com/cockroachdb/apd v1.1.0 h1:3LFP3629v+1aKXU5Q37mxmRxX/pIu1nijXydLShEq5I=

text/mustacheutil/mustacheutil.go

@@ -0,0 +1,46 @@
+package mustacheutil
+
+import (
+	"bytes"
+	"fmt"
+
+	"github.com/cbroglie/mustache"
+)
+
+type MustacheSet struct {
+	Filenames map[string]string
+	Templates map[string]*mustache.Template
+}
+
+func (ms *MustacheSet) ReadTemplates() error {
+	for key, filename := range ms.Filenames {
+		if filename == "" {
+			continue
+		}
+		if tmpl, err := mustache.ParseFile(filename); err != nil {
+			return err
+		} else {
+			if ms.Templates == nil {
+				ms.Templates = map[string]*mustache.Template{}
+			}
+			ms.Templates[key] = tmpl
+		}
+	}
+	return nil
+}
+
+func (ms *MustacheSet) RenderTemplate(key string, data map[string]string) (*bytes.Buffer, error) {
+	tmpl, ok := ms.Templates[key]
+	if !ok {
+		return nil, fmt.Errorf("template key not present for key (%s)", key)
+	} else if tmpl == nil {
+		return nil, fmt.Errorf("template is nil for key (%s)", key)
+	} else {
+		var buf bytes.Buffer
+		if err := tmpl.FRender(&buf, data); err != nil {
+			return nil, err
+		} else {
+			return &buf, nil
+		}
+	}
+}