From 2768ac0b314b175155954d256802a57b7087ca3f Mon Sep 17 00:00:00 2001
From: James Renken <james@renken.is>
Date: Wed, 25 Sep 2024 15:49:07 -0700
Subject: [PATCH 1/3] Change ClearEmail to use direct UPDATE query

---
 sa/model.go | 16 ++++++++++------
 1 file changed, 10 insertions(+), 6 deletions(-)

diff --git a/sa/model.go b/sa/model.go
index 5d0a15fd9bf..3f0c825f047 100644
--- a/sa/model.go
+++ b/sa/model.go
@@ -88,14 +88,18 @@ func ClearEmail(ctx context.Context, dbMap db.DatabaseMap, regID int64, email st
 			return nil, nil
 		}
 
-		currPb.Contact = newContacts
-		newModel, err := registrationPbToModel(currPb)
-		if err != nil {
-			return nil, err
-		}
+		// UPDATE the row with a direct database query, in order to avoid LockCol issues.
+		//
+		// TODO(#7716): Revert to use tx.Update() once LockCol has been removed.
+		_, err = dbMap.ExecContext(ctx,
+			"UPDATE registrations SET contact = ? WHERE id = ? LIMIT 1",
+			newContacts,
+			regID,
+		)
 
-		return tx.Update(ctx, newModel)
+		return nil, err
 	})
+
 	if overallError != nil {
 		return overallError
 	}

From 32d58476f0f165811f815479a383f4247712ce8b Mon Sep 17 00:00:00 2001
From: James Renken <james@renken.is>
Date: Thu, 26 Sep 2024 13:58:21 -0700
Subject: [PATCH 2/3] Address feedback & fix JSON data type

---
 sa/model.go | 27 ++++++++++++++++++++++-----
 1 file changed, 22 insertions(+), 5 deletions(-)

diff --git a/sa/model.go b/sa/model.go
index 3f0c825f047..548c63a8c07 100644
--- a/sa/model.go
+++ b/sa/model.go
@@ -88,16 +88,33 @@ func ClearEmail(ctx context.Context, dbMap db.DatabaseMap, regID int64, email st
 			return nil, nil
 		}
 
+		// We don't want to write literal JSON "null" strings into the database if the
+		// list of contact addresses is empty. Replace any possibly-`nil` slice with
+		// an empty JSON array. We don't need to check reg.ContactPresent, because
+		// we're going to write the whole object to the database anyway.
+		jsonContact := []byte("[]")
+		if len(newContacts) != 0 {
+			jsonContact, err = json.Marshal(newContacts)
+			if err != nil {
+				return nil, err
+			}
+		}
+
 		// UPDATE the row with a direct database query, in order to avoid LockCol issues.
-		//
-		// TODO(#7716): Revert to use tx.Update() once LockCol has been removed.
-		_, err = dbMap.ExecContext(ctx,
+		result, err := tx.ExecContext(ctx,
 			"UPDATE registrations SET contact = ? WHERE id = ? LIMIT 1",
-			newContacts,
+			jsonContact,
 			regID,
 		)
+		if err != nil {
+			return nil, err
+		}
+		rowsAffected, err := result.RowsAffected()
+		if err != nil || rowsAffected != 1 {
+			return nil, berrors.InternalServerError("no registration updated with new contact field")
+		}
 
-		return nil, err
+		return nil, nil
 	})
 
 	if overallError != nil {

From 625fd012077aae38ca67d7f86fce3af9ec98a655 Mon Sep 17 00:00:00 2001
From: James Renken <james@renken.is>
Date: Thu, 26 Sep 2024 14:00:26 -0700
Subject: [PATCH 3/3] Remove newline for style

---
 sa/model.go | 1 -
 1 file changed, 1 deletion(-)

diff --git a/sa/model.go b/sa/model.go
index 548c63a8c07..fa3ce717a29 100644
--- a/sa/model.go
+++ b/sa/model.go
@@ -116,7 +116,6 @@ func ClearEmail(ctx context.Context, dbMap db.DatabaseMap, regID int64, email st
 
 		return nil, nil
 	})
-
 	if overallError != nil {
 		return overallError
 	}