Set thread for incoming replies (#254)

* Correctly set thread for incoming replies * Add more logs when determining thread * Fix error with sent emails * Correctly return email sent time for sent emails
harryzcy · Apr 3, 2023 · 9a0269b · 9a0269b
1 parent 9c8ac0f
commit 9a0269b
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Showing 2 changed files with 64 additions and 25 deletions.
diff --git a/internal/email/get.go b/internal/email/get.go
@@ -117,8 +117,8 @@ func parseGetResult(attributeValues map[string]dynamodbTypes.AttributeValue) (*G
 	} else {
 		if result.Type == EmailTypeDraft {
 			result.TimeUpdated = emailTime
-		} else {
-			result.DateSent = emailTime
+		} else if result.Type == EmailTypeSent {
+			result.TimeSent = emailTime
 		}
 		result.Unread = nil
 	}

diff --git a/internal/email/thread.go b/internal/email/thread.go
@@ -3,6 +3,7 @@ package email
 import (
 	"context"
 	"errors"
+	"fmt"
 	"log"
 	"os"
 	"strings"
@@ -144,6 +145,7 @@ type DetermineThreadOutput struct {
 // If a thread already exists, the ThreadID is returned and Exists is true.
 // If a thread does not exist and a new thread should be created, the ThreadID is randomly generated and ShouldCreate is true.
 func DetermineThread(ctx context.Context, api QueryAndGetItemAPI, input *DetermineThreadInput) (*DetermineThreadOutput, error) {
+	fmt.Println("Determining thread...")
 	originalMessageID := ""
 	if len(input.InReplyTo) > 0 {
 		originalMessageID = input.InReplyTo
@@ -156,57 +158,94 @@ func DetermineThread(ctx context.Context, api QueryAndGetItemAPI, input *Determi
 		return &DetermineThreadOutput{}, nil
 	}
 
-	resp, err := api.Query(ctx, &dynamodb.QueryInput{
-		TableName:              aws.String(tableName),
-		IndexName:              aws.String(gsiOriginalIndexName),
-		KeyConditionExpression: aws.String("OriginalMessageID = :originalMessageID"),
-		ExpressionAttributeValues: map[string]dynamodbTypes.AttributeValue{
-			":originalMessageID": &dynamodbTypes.AttributeValueMemberS{Value: originalMessageID},
-		},
-	})
-	if err != nil {
-		if apiErr := new(dynamodbTypes.ProvisionedThroughputExceededException); errors.As(err, &apiErr) {
-			return nil, ErrTooManyRequests
-		}
-		return nil, err
+	sesDomain := region + ".amazonses.com"
+	var possibleSentID string
+	if strings.HasSuffix(originalMessageID, "@"+sesDomain+">") {
+		fmt.Println("incoming email is replying to a SES email")
+		// If the messageID ends with @<SES domain>, it maybe a messageID of a sent email.
+		// In this case, we need check if there's a corresponding sent email.
+		possibleSentID = strings.TrimSuffix(originalMessageID, "@"+sesDomain+">")
+		possibleSentID = strings.TrimPrefix(possibleSentID, "<")
 	}
-	// TODO: handle the case where len(resp.Items) > 1
-	if len(resp.Items) != 1 {
-		return &DetermineThreadOutput{}, nil
+
+	var previousEmail *GetResult
+	var err error
+	isSentEmail := false
+	if possibleSentID != "" {
+		// Check if the messageID is a sent email first
+		fmt.Println("checking possible sent email")
+		previousEmail, err = Get(ctx, api, possibleSentID)
+		if err != nil && !errors.Is(err, ErrNotFound) {
+			return nil, err
+		}
+		isSentEmail = true
 	}
 
-	searchMessageID := resp.Items[0]["MessageID"].(*dynamodbTypes.AttributeValueMemberS).Value
-	previousEmail, err := Get(ctx, api, searchMessageID)
-	if err != nil {
-		if errors.Is(err, ErrNotFound) {
+	if previousEmail == nil {
+		// If the messageID does not corresponded to a sent email, check if it's a received email
+		fmt.Println("checking original messageID")
+		var resp *dynamodb.QueryOutput
+		resp, err = api.Query(ctx, &dynamodb.QueryInput{
+			TableName:              aws.String(tableName),
+			IndexName:              aws.String(gsiOriginalIndexName),
+			KeyConditionExpression: aws.String("OriginalMessageID = :originalMessageID"),
+			ExpressionAttributeValues: map[string]dynamodbTypes.AttributeValue{
+				":originalMessageID": &dynamodbTypes.AttributeValueMemberS{Value: originalMessageID},
+			},
+		})
+		if err != nil {
+			if apiErr := new(dynamodbTypes.ProvisionedThroughputExceededException); errors.As(err, &apiErr) {
+				return nil, ErrTooManyRequests
+			}
+			return nil, err
+		}
+		// TODO: handle the case where len(resp.Items) > 1
+		if len(resp.Items) == 0 {
 			return &DetermineThreadOutput{}, nil
 		}
-		return nil, err
+
+		searchMessageID := resp.Items[0]["MessageID"].(*dynamodbTypes.AttributeValueMemberS).Value
+		previousEmail, err = Get(ctx, api, searchMessageID)
+		if err != nil {
+			if errors.Is(err, ErrNotFound) {
+				return &DetermineThreadOutput{}, nil
+			}
+			return nil, err
+		}
 	}
 
 	if previousEmail.ThreadID == "" {
+		// There's no thread for previousEmail, so we need to create a new thread
+		fmt.Println("determining thread finished: new thread should be created")
 		threadID := generateThreadID()
-		return &DetermineThreadOutput{
+		output := &DetermineThreadOutput{
 			ThreadID:        threadID,
 			ShouldCreate:    true,
 			CreatingEmailID: previousEmail.MessageID,
 			CreatingSubject: previousEmail.Subject,
 			CreatingTime:    previousEmail.TimeReceived,
-		}, nil
+		}
+		if isSentEmail {
+			output.CreatingTime = previousEmail.TimeSent
+		}
+		return output, nil
 	}
 
 	if previousEmail.IsThreadLatest {
+		fmt.Println("determining thread finished: previous email is the latest email in the thread")
 		return &DetermineThreadOutput{
 			ThreadID:          previousEmail.ThreadID,
 			Exists:            true,
 			PreviousMessageID: previousEmail.MessageID,
 		}, nil
 	}
 
+	fmt.Println("determining thread finished: previous email is not the latest email in the thread")
 	thread, err := GetThread(ctx, api, previousEmail.ThreadID)
 	if err != nil {
 		return nil, err
 	}
+	fmt.Println("get existing thread finished")
 	return &DetermineThreadOutput{
 		ThreadID:          previousEmail.ThreadID,
 		Exists:            true,