From 9a85d766d7c40da4746cef21904eef6df1ff10bf Mon Sep 17 00:00:00 2001
From: kert <kert@rack.localdomain>
Date: Sat, 31 Oct 2026 20:49:08 -0400
Subject: [PATCH] feat(prisma): Congress.gov bill parser

---
 src/prisma/congress.py        | 53 +++++++++++++++++++++++++++++++++++
 tests/prisma/test_congress.py | 51 +++++++++++++++++++++++++++++++++
 2 files changed, 104 insertions(+)
 create mode 100644 src/prisma/congress.py
 create mode 100644 tests/prisma/test_congress.py

diff --git a/src/prisma/congress.py b/src/prisma/congress.py
new file mode 100644
index 0000000..b15bc35
--- /dev/null
+++ b/src/prisma/congress.py
@@ -0,0 +1,53 @@
+"""Congress.gov bill list. The HTTP call is a transport the caller supplies."""
+
+from __future__ import annotations
+
+from collections.abc import Callable, Mapping
+from dataclasses import dataclass
+
+_BILL_URL = "https://api.congress.gov/v3/bill/{congress}?api_key={key}&format=json"
+
+
+@dataclass(frozen=True)
+class Bill:
+    congress: int
+    bill_type: str
+    number: int
+    title: str
+    latest_action: str
+
+
+def parse_bills(payload: Mapping[str, object]) -> tuple[Bill, ...]:
+    """Read the ``bills`` array. Missing action text becomes an empty string."""
+    raw = payload.get("bills") or ()
+    bills: list[Bill] = []
+    if not isinstance(raw, list):
+        return ()
+    for item in raw:
+        if not isinstance(item, Mapping):
+            continue
+        action = item.get("latestAction") or {}
+        text = action.get("text") if isinstance(action, Mapping) else ""
+        bills.append(
+            Bill(
+                congress=int(item["congress"]),
+                bill_type=str(item.get("type") or ""),
+                number=int(item["number"]),
+                title=str(item.get("title") or ""),
+                latest_action=str(text or ""),
+            )
+        )
+    return tuple(bills)
+
+
+def fetch_bills(
+    congress: int,
+    *,
+    key: str,
+    transport: Callable[[str], Mapping[str, object]],
+) -> tuple[Bill, ...]:
+    """GET the bill list for one congress. An empty key raises and does not fetch."""
+    if not key:
+        raise ValueError("Congress.gov API key is required")
+    payload = transport(_BILL_URL.format(congress=congress, key=key))
+    return parse_bills(payload)
diff --git a/tests/prisma/test_congress.py b/tests/prisma/test_congress.py
new file mode 100644
index 0000000..6b8c967
--- /dev/null
+++ b/tests/prisma/test_congress.py
@@ -0,0 +1,51 @@
+"""Congress.gov bill payloads. The transport is injected. No HTTP."""
+
+from __future__ import annotations
+
+import pytest
+
+from prisma.congress import Bill, fetch_bills, parse_bills
+
+_PAYLOAD = {
+    "bills": [
+        {
+            "congress": 119,
+            "type": "hr",
+            "number": 1,
+            "title": "A bill",
+            "latestAction": {"text": "Introduced"},
+        }
+    ]
+}
+_BILL = Bill(
+    congress=119,
+    bill_type="hr",
+    number=1,
+    title="A bill",
+    latest_action="Introduced",
+)
+
+
+def test_parse_bills_reads_one_bill():
+    assert parse_bills(_PAYLOAD) == (_BILL,)
+
+
+def test_fetch_bills_passes_the_congress_url_to_the_transport():
+    seen: list[str] = []
+
+    def transport(url: str) -> dict[str, object]:
+        seen.append(url)
+        return _PAYLOAD
+
+    assert fetch_bills(119, key="test-key", transport=transport) == (_BILL,)
+    assert len(seen) == 1
+    assert "119" in seen[0]
+    assert "api_key=test-key" in seen[0]
+
+
+def test_empty_key_does_not_call_the_transport():
+    def transport(url: str) -> dict[str, object]:
+        raise AssertionError(url)
+
+    with pytest.raises(ValueError):
+        fetch_bills(119, key="", transport=transport)