feat: add FileAttachment type and functions for creating attachments from file content and file path

client/attachment.go

@@ -0,0 +1,33 @@
+package client
+
+import (
+	"encoding/base64"
+	"io"
+	"os"
+)
+
+func NewAttachmentFromFileContent(fileName string, f []byte) (*FileAttachment, error) {
+	base64.StdEncoding.Encode(f, f)
+
+	return &FileAttachment{
+		Filename: fileName,
+		Content:  string(f),
+	}, nil
+}
+
+func NewAttachmentFromFilePath(filePath string) (*FileAttachment, error) {
+	f, err := os.Open(filePath)
+	if err != nil {
+		return nil, err
+	}
+	defer func(f *os.File) {
+		_ = f.Close()
+	}(f)
+
+	content, err := io.ReadAll(f)
+	if err != nil {
+		return nil, err
+	}
+
+	return NewAttachmentFromFileContent(filePath, content)
+}