From 06ae7bc0b2c73234e12f0152d6a2db3a2f3eebdd Mon Sep 17 00:00:00 2001
From: Spencer Connaughton <spencer@spencerconnaughton.com>
Date: Mon, 19 Feb 2024 17:10:17 -0500
Subject: [PATCH] Use constants for disposition.

---
 examples/helpers/mail/example.go            |  5 ++---
 helpers/mail/mail_v3.go                     | 21 ++++++++++++++-------
 helpers/mail/mail_v3_test.go                |  2 +-
 use-cases/attachments-with-mailer-helper.md |  8 ++++----
 4 files changed, 21 insertions(+), 15 deletions(-)

diff --git a/examples/helpers/mail/example.go b/examples/helpers/mail/example.go
index 53c68dbd..a7cda206 100644
--- a/examples/helpers/mail/example.go
+++ b/examples/helpers/mail/example.go
@@ -6,7 +6,6 @@ import (
 	"fmt"
 	"os"
 
-	"github.com/sendgrid/sendgrid-go"
 	"github.com/sendgrid/sendgrid-go/helpers/mail"
 )
 
@@ -102,14 +101,14 @@ func kitchenSink() []byte {
 	a.SetContent("TG9yZW0gaXBzdW0gZG9sb3Igc2l0IGFtZXQsIGNvbnNlY3RldHVyIGFkaXBpc2NpbmcgZWxpdC4gQ3JhcyBwdW12")
 	a.SetType("application/pdf")
 	a.SetFilename("balance_001.pdf")
-	a.SetDisposition("attachment")
+	a.SetDisposition(mail.DispositionAttachment)
 	m.AddAttachment(a)
 
 	a2 := mail.NewAttachment()
 	a2.SetContent("BwdW")
 	a2.SetType("image/png")
 	a2.SetFilename("banner.png")
-	a2.SetDisposition("inline")
+	a2.SetDisposition(mail.DispositionInline)
 	// Content-ID header is included when the attachment disposition is set to "inline"
 	a2.SetContentID("Banner")
 	m.AddAttachment(a2)
diff --git a/helpers/mail/mail_v3.go b/helpers/mail/mail_v3.go
index 6d7ac6b4..7cbb3701 100644
--- a/helpers/mail/mail_v3.go
+++ b/helpers/mail/mail_v3.go
@@ -66,14 +66,21 @@ type Content struct {
 	Value string `json:"value,omitempty"`
 }
 
+type disposition string
+
+const (
+	DispositionInline     disposition = "inline"
+	DispositionAttachment disposition = "attachment"
+)
+
 // Attachment holds attachement information
 type Attachment struct {
-	Content     string `json:"content,omitempty"`
-	Type        string `json:"type,omitempty"`
-	Name        string `json:"name,omitempty"`
-	Filename    string `json:"filename,omitempty"`
-	Disposition string `json:"disposition,omitempty"`
-	ContentID   string `json:"content_id,omitempty"`
+	Content     string      `json:"content,omitempty"`
+	Type        string      `json:"type,omitempty"`
+	Name        string      `json:"name,omitempty"`
+	Filename    string      `json:"filename,omitempty"`
+	Disposition disposition `json:"disposition,omitempty"`
+	ContentID   string      `json:"content_id,omitempty"`
 }
 
 // Asm contains Grpip Id and int array of groups ID
@@ -393,7 +400,7 @@ func (a *Attachment) SetFilename(filename string) *Attachment {
 }
 
 // SetDisposition ...
-func (a *Attachment) SetDisposition(disposition string) *Attachment {
+func (a *Attachment) SetDisposition(disposition disposition) *Attachment {
 	a.Disposition = disposition
 	return a
 }
diff --git a/helpers/mail/mail_v3_test.go b/helpers/mail/mail_v3_test.go
index 28af9192..40139ca2 100644
--- a/helpers/mail/mail_v3_test.go
+++ b/helpers/mail/mail_v3_test.go
@@ -406,7 +406,7 @@ func TestV3AttachmentSetContentID(t *testing.T) {
 }
 
 func TestV3AttachmentSetDisposition(t *testing.T) {
-	disposition := "inline"
+	disposition := DispositionInline
 	a := NewAttachment().SetDisposition(disposition)
 
 	assert.Equal(t, disposition, a.Disposition, fmt.Sprintf("Disposition should be %s, got %s", disposition, a.Disposition))
diff --git a/use-cases/attachments-with-mailer-helper.md b/use-cases/attachments-with-mailer-helper.md
index a6da7e5c..6f272c85 100644
--- a/use-cases/attachments-with-mailer-helper.md
+++ b/use-cases/attachments-with-mailer-helper.md
@@ -12,7 +12,7 @@ import (
   "github.com/sendgrid/sendgrid-go"
   "github.com/sendgrid/sendgrid-go/helpers/mail"
 )
-
+[]()
 func main() {
   // create new *SGMailV3
   m := mail.NewV3Mail()
@@ -42,7 +42,7 @@ func main() {
   a_txt.SetContent(encoded)
   a_txt.SetType("text/plain")
   a_txt.SetFilename("testing.txt")
-  a_txt.SetDisposition("attachment")
+  a_txt.SetDisposition(mail.DispositionAttachment)
   
   // read/attach .pdf file
   a_pdf := mail.NewAttachment()
@@ -54,7 +54,7 @@ func main() {
   a_pdf.SetContent(encoded)
   a_pdf.SetType("application/pdf")
   a_pdf.SetFilename("testing.pdf")
-  a_pdf.SetDisposition("attachment")
+  a_pdf.SetDisposition(mail.DispositionAttachment)
 
   // read/attach inline .jpg file
   a_jpg := mail.NewAttachment()
@@ -66,7 +66,7 @@ func main() {
   a_jpg.SetContent(encoded)
   a_jpg.SetType("image/jpeg")
   a_jpg.SetFilename("testing.jpg")
-  a_jpg.SetDisposition("inline")
+  a_jpg.SetDisposition(mail.DispositionInline)
   a_jpg.SetContentID("Test Attachment")
   
   // add `a_txt`, `a_pdf` and `a_jpg` to `m`