Do not fail export on email attachments without name (#23)

* Do not fail on email attachments without name

* Add changelog entry

* Allow posts to also have unnamed attachments

CHANGELOG.md

@@ -10,6 +10,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Handle the case where an email or event cannot be retrieved from Exchange due to an `ErrorCorruptData` error. Corso will skip over the item but report it in the backup summary.
 - Emails attached within other emails are now correctly exported
 - Use correct timezone for event start and end times in Exchange exports (helps fix issues in relative recurrence patterns)
+- Gracefully handle email and post attachments without name when exporting to eml
 
 ## [v0.19.0] (beta) - 2024-02-06
 

src/internal/converters/eml/eml.go

@@ -171,6 +171,13 @@ func getFileAttachment(ctx context.Context, attachment models.Attachmentable) (*
 	}
 
 	name := ptr.Val(attachment.GetName())
+	if len(name) == 0 {
+		// Graph as of now does not let us create any attachments
+		// without a name, but we have run into instances where we have
+		// see attachments without a name, possibly from old
+		// data. This is for those cases.
+		name = "Unnamed"
+	}
 
 	contentID, err := attachment.GetBackingStore().Get("contentId")
 	if err != nil {
@@ -472,6 +479,9 @@ func FromJSONPostToEML(
 			}
 
 			name := ptr.Val(attachment.GetName())
+			if len(name) == 0 {
+				name = "Unnamed"
+			}
 
 			contentID, err := attachment.GetBackingStore().Get("contentId")
 			if err != nil {

src/internal/converters/eml/eml_test.go

@@ -162,6 +162,18 @@ func (suite *EMLUnitSuite) TestConvert_edge_cases() {
 				require.NoError(suite.T(), err, "setting attachment content")
 			},
 		},
+		{
+			name: "attachment without name",
+			transform: func(msg models.Messageable) {
+				attachments := msg.GetAttachments()
+				attachments[1].SetName(ptr.To(""))
+
+				// This test has to be run on a non inline attachment
+				// as inline attachments use contentID instead of name
+				// even when there is a name.
+				assert.False(suite.T(), ptr.Val(attachments[1].GetIsInline()))
+			},
+		},
 	}
 
 	for _, test := range tests {