Specify a larger length as the default of 200 isn't always enough (#5114)

CHANGELOG.txt

@@ -60,6 +60,7 @@ Changelog
  * Fix: Updated draftjs_exporter to 2.1.5 to fix bug in handling adjacent entities (Thibaud Colas)
  * Fix: Page titles consisting only of stopwords now generate a non-empty default slug (Andy Chosak, Janneke Janssen)
  * Fix: Sitemap generator now allows passing a sitemap instance in the URL configuration (Mitchel Cabuloy, Dan Braghis)
+ * Fix: Increase max length on `Embed.thumbnail_url` to 255 characters (Kevin Howbrook)
 
 
 2.3 LTS (23.10.2018)

docs/releases/2.5.rst

@@ -41,6 +41,7 @@ Bug fixes
  * Page Copy will now also copy ParentalManyToMany field relations (LB (Ben Johnston))
  * Admin HTML header now includes correct language code (Matt Westcott)
  * Unclear error message when saving image after focal point edit (Hugo van den Berg)
+ * Fix: Increase max length on ``Embed.thumbnail_url`` to 255 characters (Kevin Howbrook)
 
 
 Upgrade considerations

wagtail/embeds/migrations/0005_specify_thumbnail_url_max_length.py

@@ -0,0 +1,18 @@
+# Generated by Django 2.1.7 on 2019-03-04 08:49
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('wagtailembeds', '0004_embed_verbose_name_plural'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='embed',
+            name='thumbnail_url',
+            field=models.URLField(blank=True, max_length=255, null=True),
+        ),
+    ]

wagtail/embeds/models.py

@@ -27,7 +27,7 @@ class Embed(models.Model):
     title = models.TextField(blank=True)
     author_name = models.TextField(blank=True)
     provider_name = models.TextField(blank=True)
-    thumbnail_url = models.URLField(null=True, blank=True)
+    thumbnail_url = models.URLField(max_length=255, null=True, blank=True)
     width = models.IntegerField(null=True, blank=True)
     height = models.IntegerField(null=True, blank=True)
     last_updated = models.DateTimeField(auto_now=True)