Truncate input-data that exceeds max_length

Avoiding any (1406, "Data too long for column ...") on MySQL.

For the 'plainly provided' fields I followed the documented maximums which are
also our DB maximums. For calculated_* I harmonized with what Sentry &
GlitchTip both do (and which was already partially reflected in the code), i.e.
128 and 1024.

events/migrations/0016_truncate_exception_type_128.py

@@ -0,0 +1,20 @@
+from django.db import migrations
+from django.db.models import F
+from django.db.models.functions import Substr, Length
+
+
+def truncate_exception_type_128(apps, schema_editor):
+    Event = apps.get_model("events", "Event")
+    Event.objects.annotate(
+        l=Length('calculated_type')).filter(l__gte=128).update(calculated_type=Substr(F('calculated_type'), 1, 128))
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ("events", "0004_b_squashed"),
+    ]
+
+    operations = [
+        migrations.RunPython(truncate_exception_type_128),
+    ]

events/migrations/0017_alter_event_calculated_type_and_more.py

@@ -0,0 +1,23 @@
+# Generated by Django 4.2.19 on 2025-02-08 19:53
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ("events", "0016_truncate_exception_type_128"),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name="event",
+            name="calculated_type",
+            field=models.CharField(blank=True, default="", max_length=128),
+        ),
+        migrations.AlterField(
+            model_name="event",
+            name="calculated_value",
+            field=models.TextField(blank=True, default="", max_length=1024),
+        ),
+    ]

events/models.py

@@ -127,8 +127,8 @@ class Event(models.Model):
     debug_info = models.CharField(max_length=255, blank=True, null=False, default="")
 
     # denormalized/cached fields:
-    calculated_type = models.CharField(max_length=255, blank=True, null=False, default="")
-    calculated_value = models.CharField(max_length=255, blank=True, null=False, default="")
+    calculated_type = models.CharField(max_length=128, blank=True, null=False, default="")
+    calculated_value = models.TextField(max_length=1024, blank=True, null=False, default="")
     # transaction = models.CharField(max_length=200, blank=True, null=False, default="")  defined first-class above
     last_frame_filename = models.CharField(max_length=255, blank=True, null=False, default="")
     last_frame_module = models.CharField(max_length=255, blank=True, null=False, default="")
@@ -201,6 +201,9 @@ class Event(models.Model):
 
         irrelevance_for_retention = get_random_irrelevance(stored_event_count)
 
+        # A note on truncation (max_length): the fields we truncate here are directly from the SDK, so they "should have
+        # been" truncated already. But we err on the side of caution: this is the kind of SDK error that we can, and
+        # just want to, paper over (it's not worth dropping the event for).
         try:
             event = cls.objects.create(
                 event_id=event_metadata["event_id"],  # the metadata is the envelope's event_id, which takes precedence
@@ -212,25 +215,25 @@ class Event(models.Model):
                 data=json.dumps(parsed_data),
 
                 timestamp=parse_timestamp(parsed_data["timestamp"]),
-                platform=parsed_data["platform"],
+                platform=parsed_data["platform"][:64],
 
                 level=maybe_empty(parsed_data.get("level", "")),
-                logger=maybe_empty(parsed_data.get("logger", "")),
+                logger=maybe_empty(parsed_data.get("logger", ""))[:64],
                 # transaction=maybe_empty(parsed_data.get("transaction", "")), part of denormalized_fields
 
-                server_name=maybe_empty(parsed_data.get("server_name", "")),
-                release=maybe_empty(parsed_data.get("release", "")),
-                dist=maybe_empty(parsed_data.get("dist", "")),
+                server_name=maybe_empty(parsed_data.get("server_name", ""))[:255],
+                release=maybe_empty(parsed_data.get("release", ""))[:250],
+                dist=maybe_empty(parsed_data.get("dist", ""))[:64],
 
-                environment=maybe_empty(parsed_data.get("environment", "")),
+                environment=maybe_empty(parsed_data.get("environment", ""))[:64],
 
-                sdk_name=maybe_empty(parsed_data.get("", {}).get("name", "")),
-                sdk_version=maybe_empty(parsed_data.get("", {}).get("version", "")),
+                sdk_name=maybe_empty(parsed_data.get("", {}).get("name", ""))[:255],
+                sdk_version=maybe_empty(parsed_data.get("", {}).get("version", ""))[:255],
 
                 has_exception="exception" in parsed_data,
                 has_logentry="logentry" in parsed_data,
 
-                debug_info=event_metadata["debug_info"],
+                debug_info=event_metadata["debug_info"][:255],
 
                 digest_order=digest_order,
                 irrelevance_for_retention=irrelevance_for_retention,

issues/utils.py

@@ -64,7 +64,7 @@ def get_exception_type_and_value_for_logmessage(data):
     )
 
     if message:
-        return "Log Message", message.splitlines()[0]
+        return "Log Message", message.splitlines()[0][:1024]
 
     return "Log Message", "<no log message>"