Feat: metadata endpoint (#512)

eligibility_server/app.py

@@ -9,6 +9,7 @@
 from flask_restful import Api
 
 from eligibility_server import __version__, db, sentry
+from eligibility_server.db.models import Metadata
 from eligibility_server.keypair import get_server_public_key
 from eligibility_server.settings import Configuration
 from eligibility_server.verify import Verify
@@ -53,6 +54,17 @@ def healthcheck():
     return TextResponse("Healthy")
 
 
+@app.route("/metadata")
+def metadata():
+    app.logger.info("Request metadata")
+
+    md = Metadata.query.first()
+    return {
+        "app": {"version": __version__},
+        "db": {"timestamp": md.timestamp, "users": md.users, "eligibility": md.eligibility},
+    }
+
+
 @app.route("/publickey")
 def publickey():
     app.logger.info("Request public key")

eligibility_server/db/models.py

@@ -1,6 +1,16 @@
 from eligibility_server.db import db
 
 
+class Metadata(db.Model):
+    id = db.Column(db.Integer, primary_key=True)
+    timestamp = db.Column(db.String, unique=True, nullable=False)
+    users = db.Column(db.Integer, nullable=False)
+    eligibility = db.Column(db.PickleType, nullable=False)
+
+    def __repr__(self):
+        return f"<Metadata [{self.timestamp}]: {self.users} users, {len(self.eligibility)} type{'s' if len(self.eligibility) > 1 else ''}>"  # noqa: E501
+
+
 user_eligibility = db.Table(
     "user_eligibility",
     db.Column("user_id", db.Integer, db.ForeignKey("user.id"), primary_key=True),

eligibility_server/db/setup.py

@@ -1,13 +1,14 @@
 import csv
+from datetime import datetime, timezone
 from tempfile import NamedTemporaryFile
 
 import click
 from flask import current_app
-from sqlalchemy import inspect
+from sqlalchemy import column, inspect
 import requests
 
 from eligibility_server.db import db
-from eligibility_server.db.models import User, Eligibility
+from eligibility_server.db.models import User, Eligibility, Metadata
 from eligibility_server.settings import Configuration
 
 
@@ -29,9 +30,10 @@ def init_db_command():
             click.echo("Creating table...")
             db.create_all()
             click.echo("Table created.")
-
             import_users()
 
+    update_metadata()
+
 
 def import_users():
     """
@@ -135,3 +137,17 @@ def drop_db_command():
             click.echo("Database dropped.")
         else:
             click.echo("Database does not exist.")
+
+
+def update_metadata():
+    Metadata.query.delete()
+
+    ts = datetime.now(tz=timezone.utc).isoformat(timespec="seconds")
+    users = User.query.count()
+    eligibility = [e.name for e in Eligibility.query.add_column(column("name"))]
+
+    metadata = Metadata(timestamp=ts, users=users, eligibility=eligibility)
+    db.session.add(metadata)
+    db.session.commit()
+
+    click.echo("Database metadata updated.")

terraform/front_door.tf

@@ -83,7 +83,11 @@ resource "azurerm_cdn_frontdoor_firewall_policy" "main" {
     match_condition {
       match_variable = "RequestUri"
       operator       = "BeginsWith"
-      match_values   = ["https://${azurerm_cdn_frontdoor_endpoint.main.host_name}:443/healthcheck", "https://${azurerm_cdn_frontdoor_endpoint.main.host_name}:443/static/"]
+      match_values   = [
+        "https://${azurerm_cdn_frontdoor_endpoint.main.host_name}:443/healthcheck",
+        "https://${azurerm_cdn_frontdoor_endpoint.main.host_name}:443/metadata",
+        "https://${azurerm_cdn_frontdoor_endpoint.main.host_name}:443/static/"
+      ]
     }
   }
 

tests/db/test_setup.py

@@ -1,21 +1,30 @@
+from datetime import datetime, timedelta, timezone
+
 import pytest
 from sqlalchemy import inspect
 
 from eligibility_server.db import db
-from eligibility_server.db.models import Eligibility, User
+from eligibility_server.db.models import Eligibility, Metadata, User
 
 
 @pytest.mark.usefixtures("flask")
 def test_init_db_command(runner):
     """Assumes that IMPORT_FILE_PATH is data/server.csv."""
     runner.invoke(args="drop-db")
 
+    start_time = datetime.now(tz=timezone.utc)
     result = runner.invoke(args="init-db")
 
     assert result.exit_code == 0
 
     assert User.query.count() == 26
     assert Eligibility.query.count() == 1
+    assert Metadata.query.count() == 1
+
+    metadata = Metadata.query.first()
+    assert metadata.users == User.query.count()
+    assert datetime.fromisoformat(metadata.timestamp) - start_time < timedelta(seconds=1)
+    assert metadata.eligibility == ["agency_card"]
 
     user_with_one_eligibility = User.query.filter_by(sub="32587", name="Gonzales").first()
     agency_card_type = Eligibility.query.filter_by(name="agency_card").first()

tests/test_app.py

@@ -4,6 +4,7 @@
 
 import re
 
+from eligibility_server import __version__
 from eligibility_server.settings import APP_NAME
 from eligibility_server.keypair import get_server_public_key
 
@@ -20,6 +21,23 @@ def test_healthcheck(client):
     assert "Strict-Transport-Security" in response.headers
 
 
+def test_metadata(client):
+    response = client.get("metadata")
+    assert response.status_code == 200
+    assert response.mimetype == "application/json"
+    assert "Strict-Transport-Security" in response.headers
+
+    data = response.json
+
+    assert "app" in data
+    assert data["app"]["version"] == __version__
+    assert "db" in data
+    assert isinstance(data["db"]["timestamp"], str)
+    assert isinstance(data["db"]["users"], int)
+    assert isinstance(data["db"]["eligibility"], list)
+    assert len(data["db"]["eligibility"]) > 0
+
+
 def test_404(client):
     response = client.get("/random")