Add custom JSON marshallers to cache data

notifications.go

@@ -2,7 +2,9 @@ package notifications
 
 import (
 	"bytes"
+	"encoding/json"
 	"io"
+	"io/ioutil"
 	"log"
 	"os"
 	"text/template"
@@ -109,6 +111,41 @@ func (attachment Attachment) execute(data io.Writer) error {
 	return err
 }
 
+func (attachment *Attachment) MarshalJSON() ([]byte, error) {
+	data, err := ioutil.ReadAll(attachment.Data)
+	if err != nil {
+		return []byte{}, err
+	}
+
+	return json.Marshal(&struct {
+		ContentType string `json:"content_type"`
+		Data        []byte `json:"data"`
+		Filename    string `json:"filename"`
+	}{
+		ContentType: attachment.ContentType,
+		Data:        data,
+		Filename:    attachment.Filename,
+	})
+}
+
+func (attachment *Attachment) UnmarshalJSON(data []byte) error {
+	inner := struct {
+		ContentType string `json:"content_type"`
+		Data        []byte `json:"data"`
+		Filename    string `json:"filename"`
+	}{}
+
+	if err := json.Unmarshal(data, &inner); err != nil {
+		return err
+	}
+
+	attachment.ContentType = inner.ContentType
+	attachment.Filename = inner.Filename
+	attachment.Data = bytes.NewReader(inner.Data)
+
+	return nil
+}
+
 func SendEmail(email Email) error {
 	if debugLogging {
 		log.Printf("DEBUG notifications email: %+v \n", email)

notifications_test.go

@@ -1,8 +1,12 @@
 package notifications
 
 import (
+	"encoding/json"
+	"io/ioutil"
 	"strings"
 	"testing"
+
+	"github.com/stretchr/testify/assert"
 )
 
 func TestNotificationsLive(t *testing.T) {
@@ -41,3 +45,34 @@ func TestNotificationsWithAttachmentsLive(t *testing.T) {
 		t.Fatal(err)
 	}
 }
+
+func TestJSONMarshalAndUnmarshal(t *testing.T) {
+	data := strings.NewReader("oh hi I am an attachment")
+
+	email := Email{
+		To:      "david@banham.id.au",
+		From:    "testrun@takehome.io",
+		ReplyTo: "lolwut@takehome.io",
+		Text:    "this is the text part of a test run",
+		HTML:    "this <i>is the HTML part of a test</i> run",
+		Subject: "test run",
+		Attachments: []Attachment{
+			Attachment{
+				ContentType: "text/plain",
+				Data:        data,
+				Filename:    "test_data.txt",
+			},
+		},
+	}
+
+	result, err := json.Marshal(email)
+	assert.Nil(t, err)
+
+	newEmail := Email{}
+
+	assert.Nil(t, json.Unmarshal(result, &newEmail))
+
+	contents, err := ioutil.ReadAll(newEmail.Attachments[0].Data)
+	assert.Nil(t, err)
+	assert.Equal(t, string(contents), "oh hi I am an attachment")
+}