Stator stats overhaul

Removes the error table, adds a stats table and admin page.
Fixes #166

9 files changed, 223 insertions, 47 deletions

diff --git a/stator/admin.py b/stator/admin.py
index 2d001ea..d22fd1b 100644
--- a/stator/admin.py
+++ b/stator/admin.py
@@ -1,20 +1,15 @@
 from django.contrib import admin
 
-from stator.models import StatorError
+from stator.models import Stats
 
 
-@admin.register(StatorError)
+@admin.register(Stats)
 class DomainAdmin(admin.ModelAdmin):
     list_display = [
-        "id",
-        "date",
         "model_label",
-        "instance_pk",
-        "state",
-        "error",
+        "updated",
     ]
-    list_filter = ["model_label", "date"]
-    ordering = ["-date"]
+    ordering = ["model_label"]
 
     def has_add_permission(self, request, obj=None):
         return False
diff --git a/stator/migrations/0002_stats_delete_statorerror.py b/stator/migrations/0002_stats_delete_statorerror.py
new file mode 100644
index 0000000..5d22003
--- /dev/null
+++ b/stator/migrations/0002_stats_delete_statorerror.py
@@ -0,0 +1,31 @@
+# Generated by Django 4.1.4 on 2022-12-15 18:38
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ("stator", "0001_initial"),
+    ]
+
+    operations = [
+        migrations.CreateModel(
+            name="Stats",
+            fields=[
+                (
+                    "model_label",
+                    models.CharField(max_length=200, primary_key=True, serialize=False),
+                ),
+                ("statistics", models.JSONField()),
+                ("created", models.DateTimeField(auto_now_add=True)),
+                ("updated", models.DateTimeField(auto_now=True)),
+            ],
+            options={
+                "verbose_name_plural": "Stats",
+            },
+        ),
+        migrations.DeleteModel(
+            name="StatorError",
+        ),
+    ]
diff --git a/stator/models.py b/stator/models.py
index 261584c..c6e777a 100644
--- a/stator/models.py
+++ b/stator/models.py
@@ -1,5 +1,4 @@
 import datetime
-import pprint
 import traceback
 from typing import ClassVar, cast
 
@@ -128,6 +127,19 @@ class StatorModel(models.Model):
         return await sync_to_async(cls.transition_get_with_lock)(number, lock_expiry)
 
     @classmethod
+    async def atransition_ready_count(cls) -> int:
+        """
+        Returns how many instances are "queued"
+        """
+        return await (
+            cls.objects.filter(
+                state_locked_until__isnull=True,
+                state_ready=True,
+                state__in=cls.state_graph.automatic_states,
+            ).acount()
+        )
+
+    @classmethod
     async def atransition_clean_locks(cls):
         await cls.objects.filter(state_locked_until__lte=timezone.now()).aupdate(
             state_locked_until=None
@@ -158,7 +170,6 @@ class StatorModel(models.Model):
         try:
             next_state = await current_state.handler(self)
         except BaseException as e:
-            await StatorError.acreate_from_instance(self, e)
             await exceptions.acapture_exception(e)
             traceback.print_exc()
         else:
@@ -209,46 +220,126 @@ class StatorModel(models.Model):
     atransition_perform = sync_to_async(transition_perform)
 
 
-class StatorError(models.Model):
+class Stats(models.Model):
     """
-    Tracks any errors running the transitions.
-    Meant to be cleaned out regularly. Should probably be a log.
+    Tracks summary statistics of each model over time.
     """
 
     # appname.modelname (lowercased) label for the model this represents
-    model_label = models.CharField(max_length=200)
+    model_label = models.CharField(max_length=200, primary_key=True)
 
-    # The primary key of that model (probably int or str)
-    instance_pk = models.CharField(max_length=200)
+    statistics = models.JSONField()
 
-    # The state we were on
-    state = models.CharField(max_length=200)
+    created = models.DateTimeField(auto_now_add=True)
+    updated = models.DateTimeField(auto_now=True)
 
-    # When it happened
-    date = models.DateTimeField(auto_now_add=True)
-
-    # Error name
-    error = models.TextField()
+    class Meta:
+        verbose_name_plural = "Stats"
 
-    # Error details
-    error_details = models.TextField(blank=True, null=True)
+    @classmethod
+    def get_for_model(cls, model: type[StatorModel]) -> "Stats":
+        instance = cls.objects.filter(model_label=model._meta.label_lower).first()
+        if instance is None:
+            instance = cls(model_label=model._meta.label_lower)
+        if not instance.statistics:
+            instance.statistics = {}
+        # Ensure there are the right keys
+        for key in ["queued", "hourly", "daily", "monthly"]:
+            if key not in instance.statistics:
+                instance.statistics[key] = {}
+        return instance
 
     @classmethod
-    async def acreate_from_instance(
-        cls,
-        instance: StatorModel,
-        exception: BaseException | None = None,
-    ):
-        detail = traceback.format_exc()
-        if exception and len(exception.args) > 1:
-            detail += "\n\n" + "\n\n".join(
-                pprint.pformat(arg) for arg in exception.args
-            )
+    async def aget_for_model(cls, model: type[StatorModel]) -> "Stats":
+        return await sync_to_async(cls.get_for_model)(model)
+
+    def set_queued(self, number: int):
+        """
+        Sets the current queued amount.
+
+        The queue is an instantaneous value (a "gauge") rather than a
+        sum ("counter"). It's mostly used for reporting what things are right
+        now, but basic trend analysis is also used to see if we think the
+        queue is backing up.
+        """
+        self.statistics["queued"][
+            int(timezone.now().replace(second=0, microsecond=0).timestamp())
+        ] = number
+
+    def add_handled(self, number: int):
+        """
+        Adds the "handled" number to the current stats.
+        """
+        hour = timezone.now().replace(minute=0, second=0, microsecond=0)
+        day = hour.replace(hour=0)
+        hour_timestamp = str(int(hour.timestamp()))
+        day_timestamp = str(int(day.timestamp()))
+        month_timestamp = str(int(day.replace(day=1).timestamp()))
+        self.statistics["hourly"][hour_timestamp] = (
+            self.statistics["hourly"].get(hour_timestamp, 0) + number
+        )
+        self.statistics["daily"][day_timestamp] = (
+            self.statistics["daily"].get(day_timestamp, 0) + number
+        )
+        self.statistics["monthly"][month_timestamp] = (
+            self.statistics["monthly"].get(month_timestamp, 0) + number
+        )
 
-        return await cls.objects.acreate(
-            model_label=instance._meta.label_lower,
-            instance_pk=str(instance.pk),
-            state=instance.state,
-            error=str(exception),
-            error_details=detail,
+    def trim_data(self):
+        """
+        Removes excessively old data from the field
+        """
+        queued_horizon = int((timezone.now() - datetime.timedelta(hours=2)).timestamp())
+        hourly_horizon = int(
+            (timezone.now() - datetime.timedelta(hours=50)).timestamp()
+        )
+        daily_horizon = int((timezone.now() - datetime.timedelta(days=62)).timestamp())
+        monthly_horizon = int(
+            (timezone.now() - datetime.timedelta(days=3653)).timestamp()
+        )
+        self.statistics["queued"] = {
+            ts: v
+            for ts, v in self.statistics["queued"].items()
+            if int(ts) >= queued_horizon
+        }
+        self.statistics["hourly"] = {
+            ts: v
+            for ts, v in self.statistics["hourly"].items()
+            if int(ts) >= hourly_horizon
+        }
+        self.statistics["daily"] = {
+            ts: v
+            for ts, v in self.statistics["daily"].items()
+            if int(ts) >= daily_horizon
+        }
+        self.statistics["monthly"] = {
+            ts: v
+            for ts, v in self.statistics["monthly"].items()
+            if int(ts) >= monthly_horizon
+        }
+
+    def most_recent_queued(self) -> int:
+        """
+        Returns the most recent number of how many were queued
+        """
+        queued = [(int(ts), v) for ts, v in self.statistics["queued"].items()]
+        queued.sort(reverse=True)
+        if queued:
+            return queued[0][1]
+        else:
+            return 0
+
+    def most_recent_handled(self) -> tuple[int, int, int]:
+        """
+        Returns the current handling numbers for hour, day, month
+        """
+        hour = timezone.now().replace(minute=0, second=0, microsecond=0)
+        day = hour.replace(hour=0)
+        hour_timestamp = str(int(hour.timestamp()))
+        day_timestamp = str(int(day.timestamp()))
+        month_timestamp = str(int(day.replace(day=1).timestamp()))
+        return (
+            self.statistics["hourly"].get(hour_timestamp, 0),
+            self.statistics["daily"].get(day_timestamp, 0),
+            self.statistics["monthly"].get(month_timestamp, 0),
         )
diff --git a/stator/runner.py b/stator/runner.py
index 7305a6e..ad3f660 100644
--- a/stator/runner.py
+++ b/stator/runner.py
@@ -4,12 +4,12 @@ import time
 import traceback
 import uuid
 
-from asgiref.sync import async_to_sync
+from asgiref.sync import async_to_sync, sync_to_async
 from django.utils import timezone
 
 from core import exceptions, sentry
 from core.models import Config
-from stator.models import StatorModel
+from stator.models import StatorModel, Stats
 
 
 class StatorRunner:
@@ -39,7 +39,7 @@ class StatorRunner:
 
     async def run(self):
         sentry.set_takahe_app("stator")
-        self.handled = 0
+        self.handled = {}
         self.started = time.monotonic()
         self.last_clean = time.monotonic() - self.schedule_interval
         self.tasks = []
@@ -52,7 +52,9 @@ class StatorRunner:
                     if (time.monotonic() - self.last_clean) >= self.schedule_interval:
                         # Refresh the config
                         Config.system = await Config.aload_system()
-                        print(f"{self.handled} tasks processed so far")
+                        print("Tasks processed this loop:")
+                        for label, number in self.handled.items():
+                            print(f"  {label}: {number}")
                         print("Running cleaning and scheduling")
                         await self.run_scheduling()
 
@@ -91,10 +93,23 @@ class StatorRunner:
         """
         with sentry.start_transaction(op="task", name="stator.run_scheduling"):
             for model in self.models:
+                asyncio.create_task(self.submit_stats(model))
                 asyncio.create_task(model.atransition_clean_locks())
                 asyncio.create_task(model.atransition_schedule_due())
             self.last_clean = time.monotonic()
 
+    async def submit_stats(self, model):
+        """
+        Pop some statistics into the database
+        """
+        stats_instance = await Stats.aget_for_model(model)
+        if stats_instance.model_label in self.handled:
+            stats_instance.add_handled(self.handled[stats_instance.model_label])
+            del self.handled[stats_instance.model_label]
+        stats_instance.set_queued(await model.atransition_ready_count())
+        stats_instance.trim_data()
+        await sync_to_async(stats_instance.save)()
+
     async def fetch_and_process_tasks(self):
         # Calculate space left for tasks
         space_remaining = self.concurrency - len(self.tasks)
@@ -110,7 +125,9 @@ class StatorRunner:
                     self.tasks.append(
                         asyncio.create_task(self.run_transition(instance))
                     )
-                    self.handled += 1
+                    self.handled[model._meta.label_lower] = (
+                        self.handled.get(model._meta.label_lower, 0) + 1
+                    )
                     space_remaining -= 1
 
     async def run_transition(self, instance: StatorModel):
diff --git a/takahe/urls.py b/takahe/urls.py
index dfdf4da..6bb239b 100644
--- a/takahe/urls.py
+++ b/takahe/urls.py
@@ -127,6 +127,11 @@ urlpatterns = [
         "admin/hashtags/<hashtag>/delete/",
         admin.HashtagDelete.as_view(),
     ),
+    path(
+        "admin/stator/",
+        admin.Stator.as_view(),
+        name="admin_stator",
+    ),
     # Identity views
     path("@<handle>/", identity.ViewIdentity.as_view()),
     path("@<handle>/inbox/", activitypub.Inbox.as_view()),
diff --git a/templates/admin/stator.html b/templates/admin/stator.html
new file mode 100644
index 0000000..64bd432
--- /dev/null
+++ b/templates/admin/stator.html
@@ -0,0 +1,13 @@
+{% extends "settings/base.html" %}
+
+{% block subtitle %}Stator{% endblock %}
+
+{% block content %}
+    {% for model, stats in model_stats.items %}
+        <fieldset>
+            <legend>{{ model }}</legend>
+            <p><b>Pending:</b> {{ stats.most_recent_queued }}</p>
+            <p><b>Processed today:</b> {{ stats.most_recent_handled.1 }}</p>
+        </fieldset>
+    {% endfor %}
+{% endblock %}
diff --git a/templates/settings/_menu.html b/templates/settings/_menu.html
index bcb404d..0a6062d 100644
--- a/templates/settings/_menu.html
+++ b/templates/settings/_menu.html
@@ -42,6 +42,9 @@
     <a href="{% url "admin_tuning" %}" {% if section == "tuning" %}class="selected"{% endif %} title="Tuning">
         <i class="fa-solid fa-wrench"></i> Tuning
     </a>
+    <a href="{% url "admin_stator" %}" {% if section == "stator" %}class="selected"{% endif %} title="Stator">
+        <i class="fa-solid fa-clock-rotate-left"></i> Stator
+    </a>
     <a href="/djadmin" title="">
         <i class="fa-solid fa-gear"></i> Django Admin
     </a>
diff --git a/users/views/admin/__init__.py b/users/views/admin/__init__.py
index b8ebc40..bb70ff7 100644
--- a/users/views/admin/__init__.py
+++ b/users/views/admin/__init__.py
@@ -22,6 +22,7 @@ from users.views.admin.settings import (  # noqa
     PoliciesSettings,
     TuningSettings,
 )
+from users.views.admin.stator import Stator  # noqa
 
 
 @method_decorator(admin_required, name="dispatch")
diff --git a/users/views/admin/stator.py b/users/views/admin/stator.py
new file mode 100644
index 0000000..c3ce01d
--- /dev/null
+++ b/users/views/admin/stator.py
@@ -0,0 +1,20 @@
+from django.utils.decorators import method_decorator
+from django.views.generic import TemplateView
+
+from stator.models import StatorModel, Stats
+from users.decorators import admin_required
+
+
+@method_decorator(admin_required, name="dispatch")
+class Stator(TemplateView):
+
+    template_name = "admin/stator.html"
+
+    def get_context_data(self):
+        return {
+            "model_stats": {
+                model._meta.verbose_name_plural.title(): Stats.get_for_model(model)
+                for model in StatorModel.subclasses
+            },
+            "section": "stator",
+        }