Add text-based URL field, change columns to text

api/api/models/audio.py

@@ -163,8 +163,7 @@ class Audio(AudioFileMixin, AbstractMedia):
     )
 
     # Replaces the foreign key to AudioSet
-    audio_set_foreign_identifier = models.CharField(
-        max_length=1000,
+    audio_set_foreign_identifier = models.TextField(
         blank=True,
         null=True,
         help_text="Reference to set of which this track is a part.",

api/api/models/fields.py

@@ -0,0 +1,21 @@
+from django import forms
+from django.core import validators
+from django.db import models
+from django.utils.translation import gettext_lazy as _
+
+
+class URLTextField(models.TextField):
+    """URL field which uses the underlying Postgres TEXT column type."""
+
+    default_validators = [validators.URLValidator()]
+    description = _("URL")
+
+    def formfield(self, **kwargs):
+        # As with CharField, this will cause URL validation to be performed
+        # twice.
+        return super().formfield(
+            **{
+                "form_class": forms.URLField,
+                **kwargs,
+            }
+        )

api/api/models/mixins.py

@@ -2,6 +2,8 @@
 
 from django.db import models
 
+from api.models import fields
+
 
 class IdentifierMixin(models.Model):
     """
@@ -32,11 +34,10 @@ class ForeignIdentifierMixin(models.Model):
 
     This mixin adds
 
-    - foreign_identifier: CharField
+    - foreign_identifier: TextField
     """
 
-    foreign_identifier = models.CharField(
-        max_length=1000,
+    foreign_identifier = models.TextField(
         blank=True,
         null=True,
         db_index=True,
@@ -55,34 +56,31 @@ class MediaMixin(models.Model):
 
     The mixin adds
 
-    - title: CharField
-    - foreign_landing_url: CharField
-    - creator: CharField
-    - creator_url: CharField
-    - thumbnail: URLField
+    - title: TextField
+    - foreign_landing_url: URLTextField
+    - creator: TextField
+    - creator_url: URLTextField
+    - thumbnail: URLTextField
     - provider: CharField
     """
 
-    title = models.CharField(
-        max_length=2000,
+    title = models.TextField(
         blank=True,
         null=True,
         help_text="The name of the media.",
     )
-    foreign_landing_url = models.CharField(
-        max_length=1000,
+    foreign_landing_url = fields.URLTextField(
         blank=True,
         null=True,
         help_text="The landing page of the work.",
     )
 
-    creator = models.CharField(
-        max_length=2000,
+    creator = models.TextField(
         blank=True,
         null=True,
         help_text="The name of the media creator.",
     )
-    creator_url = models.URLField(
+    creator_url = fields.URLTextField(
         max_length=2000,
         blank=True,
         null=True,
@@ -92,8 +90,7 @@ class MediaMixin(models.Model):
     # Because all forms of media have a thumbnail for visual representation
     # For images, this field is not used as images are generated using Photon.
     # For audio, this field points to the artwork, or is ``null``.
-    thumbnail = models.URLField(
-        max_length=1000,
+    thumbnail = fields.URLTextField(
         blank=True,
         null=True,
         help_text="The thumbnail for the media.",
@@ -120,12 +117,12 @@ class FileMixin(models.Model):
 
     This mixin adds
 
-    - url: URLField
+    - url: URLTextField
     - filesize: IntegerField
     - filetype: CharField
     """
 
-    url = models.URLField(
+    url = fields.URLTextField(
         unique=True,
         max_length=1000,
         help_text="The actual URL to the media file.",