fix: DynamoDB LATEST pointer + moto tests

.github/workflows/ci.yml

@@ -0,0 +1,31 @@
+name: CI
+
+on:
+  push:
+    branches: [main]
+  pull_request:
+
+permissions:
+  contents: read
+
+concurrency:
+  group: ci-${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+
+      - uses: actions/setup-python@v5
+        with:
+          python-version: "3.12"
+          cache: pip
+
+      - name: Install dependencies
+        run: pip install -r requirements.txt
+
+      - name: Run pytest
+        # moto mocks DynamoDB — no AWS credentials required
+        run: PYTHONPATH=. pytest tests/test_exclusao.py -v

README.md

@@ -18,3 +18,31 @@ API serverless para solicitação de exclusão de cliente com geração de QR Co
 ## Architecture Decision Records
 
 - [ADR-001 — Unificar exclusão Pix (CDK + Lambda)](docs/adr/ADR-001-unificar-exclusao-pix.md) — **Accepted** (CAB 2026-09-20). Este repo é o canônico; `aws-api-gateway-cdk` será arquivado após migrar o stack. Access pattern Dynamo: pointer `LATEST`. Auth (PR3): Cognito JWT.
+
+---
+
+## DynamoDB — ponteiro LATEST
+
+Tabela: PK `cliente_id`, SK `request_id`.
+
+Cada solicitação grava **dois** itens (histórico depois ponteiro):
+
+| SK | Papel |
+|----|--------|
+| UUID da solicitação | Histórico daquele pedido |
+| `LATEST` | Ponteiro do estado atual (`active_request_id`, `status`, …) |
+
+- **Dedup / status** leem só `LATEST` (antes o código gravava UUID e lia SK=`LATEST` — nunca achava).
+- **Confirmar pagamento** atualiza histórico e depois `LATEST` (condition em `active_request_id`).
+- Writes ordenados (`put`/`update`) de propósito neste PR — TransactWrite fica pra um follow-up se precisar atomicidade forte.
+
+### Testes
+
+```bash
+pip install -r requirements.txt
+PYTHONPATH=. pytest tests/test_exclusao.py -v
+```
+
+Usa **moto** (sem AWS real). O pacote `lambda/` importa via `importlib` (nome reservado).
+
+CI (GitHub Actions): mesmo comando em Python 3.12 em todo PR/`push` na `main` — sem credenciais AWS no runner.

lambda/app.py

@@ -1,108 +1,216 @@
 from aws_lambda_powertools import Logger, Tracer, Metrics
 from aws_lambda_powertools.event_handler import APIGatewayHttpResolver
 from aws_lambda_powertools.utilities.typing import LambdaContext
-from aws_lambda_powertools.utilities.idempotency import idempotent
 from aws_lambda_powertools.utilities.data_classes import APIGatewayProxyEvent
 import boto3
 import json
 import uuid
 import os
 from datetime import datetime, timedelta
+from decimal import Decimal
 
 logger = Logger(service="exclusao-cliente-lambda")
 tracer = Tracer()
 metrics = Metrics(namespace="ExclusaoCliente")
 app = APIGatewayHttpResolver()
 
-TABLE_NAME = os.environ.get('TABLE_NAME', 'ExclusaoClientes')
-PIX_FEE = float(os.environ.get('PIX_FEE', '50.00'))
+TABLE_NAME = os.environ.get("TABLE_NAME", "ExclusaoClientes")
+PIX_FEE = Decimal(str(os.environ.get("PIX_FEE", "50.00")))
+LATEST_SK = "LATEST"
 
-dynamodb = boto3.resource('dynamodb')
+dynamodb = boto3.resource("dynamodb")
 table = dynamodb.Table(TABLE_NAME)
 
-@idempotent
-@app.post('/solicitar-exclusao-cliente')
+
+def _get_latest(cliente_id: str) -> dict | None:
+    """Read the LATEST pointer row for a cliente."""
+    response = table.get_item(Key={"cliente_id": cliente_id, "request_id": LATEST_SK})
+    return response.get("Item")
+
+
+def _put_solicitacao_with_latest(
+    *,
+    cliente_id: str,
+    request_id: str,
+    motivo: str,
+    qr_code_data: str,
+    fee_amount: Decimal,
+    created_at: str,
+    expires_at: str,
+) -> None:
+    """Write history (SK=uuid) then LATEST pointer (SK=LATEST).
+
+    Ordered puts keep the PR small and moto-friendly. TransactWrite can
+    replace this later if we need stronger atomicity.
+    """
+    history = {
+        "cliente_id": cliente_id,
+        "request_id": request_id,
+        "status": "PENDING_PAYMENT",
+        "motivo": motivo,
+        "qr_code_data": qr_code_data,
+        "fee_amount": fee_amount,
+        "created_at": created_at,
+        "expires_at": expires_at,
+    }
+    latest = {
+        "cliente_id": cliente_id,
+        "request_id": LATEST_SK,
+        "active_request_id": request_id,
+        "status": "PENDING_PAYMENT",
+        "motivo": motivo,
+        "qr_code_data": qr_code_data,
+        "fee_amount": fee_amount,
+        "created_at": created_at,
+        "expires_at": expires_at,
+    }
+    table.put_item(Item=history)
+    table.put_item(Item=latest)
+
+
+def _confirm_payment(cliente_id: str, request_id: str) -> None:
+    """Mark history + LATEST as PAID when pointer matches request_id."""
+    ts = datetime.utcnow().isoformat()
+    table.update_item(
+        Key={"cliente_id": cliente_id, "request_id": request_id},
+        UpdateExpression="SET #status = :paid, updated_at = :ts",
+        ExpressionAttributeNames={"#status": "status"},
+        ExpressionAttributeValues={":paid": "PAID", ":ts": ts},
+        ConditionExpression="attribute_exists(cliente_id)",
+    )
+    table.update_item(
+        Key={"cliente_id": cliente_id, "request_id": LATEST_SK},
+        UpdateExpression="SET #status = :paid, updated_at = :ts",
+        ExpressionAttributeNames={"#status": "status"},
+        ExpressionAttributeValues={
+            ":paid": "PAID",
+            ":ts": ts,
+            ":rid": request_id,
+        },
+        ConditionExpression="active_request_id = :rid",
+    )
+
+
+def generate_pix_qr_code(cliente_id: str, amount: Decimal, request_id: str) -> str:
+    return f"pix-emv-stub://{cliente_id}/{amount}/{request_id}"
+
+
+@app.post("/solicitar-exclusao-cliente")
 @tracer.capture_method
 def solicitar_exclusao(event: APIGatewayProxyEvent):
     body = event.json_body or {}
-    cliente_id = body.get('cliente_id')
-    motivo = body.get('motivo', 'Não informado')
+    cliente_id = body.get("cliente_id")
+    motivo = body.get("motivo", "Não informado")
 
     if not cliente_id:
-        return {'statusCode': 400, 'body': json.dumps({'error': 'cliente_id is required'})}
+        return {
+            "statusCode": 400,
+            "body": json.dumps({"error": "cliente_id is required"}),
+        }
+
+    existing = _get_latest(cliente_id)
+    if existing and existing.get("status") in ("PENDING_PAYMENT", "PAID"):
+        return {
+            "statusCode": 200,
+            "body": json.dumps(
+                {
+                    "message": "Solicitação já existe",
+                    "request_id": existing.get("active_request_id"),
+                    "status": existing.get("status"),
+                }
+            ),
+        }
 
     request_id = str(uuid.uuid4())
     timestamp = datetime.utcnow().isoformat()
-
-    try:
-        response = table.get_item(Key={'cliente_id': cliente_id, 'request_id': 'LATEST'})
-        if 'Item' in response:
-            existing = response['Item']
-            if existing.get('status') in ['PENDING_PAYMENT', 'PAID']:
-                return {'statusCode': 200, 'body': json.dumps({'message': 'Solicitação já existe', 'request_id': existing.get('request_id'), 'status': existing.get('status')})}
-    except Exception:
-        pass
-
+    expires_at = (datetime.utcnow() + timedelta(days=7)).isoformat()
     qr_code_data = generate_pix_qr_code(cliente_id, PIX_FEE, request_id)
 
-    item = {
-        'cliente_id': cliente_id,
-        'request_id': request_id,
-        'status': 'PENDING_PAYMENT',
-        'motivo': motivo,
-        'qr_code_data': qr_code_data,
-        'fee_amount': PIX_FEE,
-        'created_at': timestamp,
-        'expires_at': (datetime.utcnow() + timedelta(days=7)).isoformat()
-    }
-    table.put_item(Item=item)
+    _put_solicitacao_with_latest(
+        cliente_id=cliente_id,
+        request_id=request_id,
+        motivo=motivo,
+        qr_code_data=qr_code_data,
+        fee_amount=PIX_FEE,
+        created_at=timestamp,
+        expires_at=expires_at,
+    )
 
     metrics.add_metric(name="exclusao_solicitada", unit="Count", value=1)
     logger.info("Solicitação criada", extra={"cliente_id": cliente_id})
 
-    return {'statusCode': 201, 'body': json.dumps({'message': 'Solicitação registrada', 'request_id': request_id, 'qr_code': qr_code_data, 'fee': PIX_FEE})}
+    return {
+        "statusCode": 201,
+        "body": json.dumps(
+            {
+                "message": "Solicitação registrada",
+                "request_id": request_id,
+                "qr_code": qr_code_data,
+                "fee": float(PIX_FEE),
+            }
+        ),
+    }
 
-def generate_pix_qr_code(cliente_id: str, amount: float, request_id: str) -> str:
-    return f"pix-emv-stub://{cliente_id}/{amount}/{request_id}"
 
-@app.get('/health')
+@app.get("/health")
 @tracer.capture_method
 def health_check():
     try:
         table.meta.client.describe_table(TableName=TABLE_NAME)
-        return {'statusCode': 200, 'body': json.dumps({'status': 'healthy'})}
+        return {"statusCode": 200, "body": json.dumps({"status": "healthy"})}
     except Exception as e:
-        return {'statusCode': 503, 'body': json.dumps({'status': 'unhealthy', 'error': str(e)})}
+        return {
+            "statusCode": 503,
+            "body": json.dumps({"status": "unhealthy", "error": str(e)}),
+        }
 
-@app.get('/status-exclusao/{cliente_id}')
+
+@app.get("/status-exclusao/{cliente_id}")
 @tracer.capture_method
 def get_status(cliente_id: str):
     try:
-        response = table.get_item(Key={'cliente_id': cliente_id, 'request_id': 'LATEST'})
-        if 'Item' in response:
-            item = response['Item']
-            return {'statusCode': 200, 'body': json.dumps({'cliente_id': cliente_id, 'status': item.get('status'), 'request_id': item.get('request_id')})}
-        return {'statusCode': 404, 'body': json.dumps({'error': 'Não encontrado'})}
+        item = _get_latest(cliente_id)
+        if item:
+            return {
+                "statusCode": 200,
+                "body": json.dumps(
+                    {
+                        "cliente_id": cliente_id,
+                        "status": item.get("status"),
+                        "request_id": item.get("active_request_id"),
+                    }
+                ),
+            }
+        return {"statusCode": 404, "body": json.dumps({"error": "Não encontrado"})}
     except Exception as e:
-        return {'statusCode': 500, 'body': json.dumps({'error': str(e)})}
+        return {"statusCode": 500, "body": json.dumps({"error": str(e)})}
+
 
-@app.post('/confirmar-pagamento')
+@app.post("/confirmar-pagamento")
 @tracer.capture_method
 def confirmar_pagamento(event: APIGatewayProxyEvent):
     body = event.json_body or {}
+    cliente_id = body.get("cliente_id")
+    request_id = body.get("request_id")
+    if not cliente_id or not request_id:
+        return {
+            "statusCode": 400,
+            "body": json.dumps(
+                {"error": "cliente_id and request_id are required"}
+            ),
+        }
     try:
-        table.update_item(
-            Key={'cliente_id': body.get('cliente_id'), 'request_id': body.get('request_id')},
-            UpdateExpression='SET #status = :paid, updated_at = :ts',
-            ExpressionAttributeNames={'#status': 'status'},
-            ExpressionAttributeValues={':paid': 'PAID', ':ts': datetime.utcnow().isoformat()}
-        )
+        _confirm_payment(cliente_id, request_id)
         metrics.add_metric(name="exclusao_paga", unit="Count", value=1)
-        return {'statusCode': 200, 'body': json.dumps({'message': 'Pagamento confirmado'})}
+        return {
+            "statusCode": 200,
+            "body": json.dumps({"message": "Pagamento confirmado"}),
+        }
     except Exception as e:
-        return {'statusCode': 500, 'body': json.dumps({'error': str(e)})}
+        return {"statusCode": 500, "body": json.dumps({"error": str(e)})}
+
 
 @logger.inject_lambda_context(correlation_id_path="requestContext.requestId")
 @tracer.capture_lambda_handler
 def lambda_handler(event: dict, context: LambdaContext) -> dict:
-    return app.resolve(event, context)
+    return app.resolve(event, context)

requirements.txt

@@ -1,3 +1,7 @@
 aws-lambda-powertools[all]
 boto3
 qrcode  # for real QR if needed
+
+# Local / CI testing
+pytest>=8.0.0
+moto[dynamodb]>=5.0.0

tests/test_app.py

@@ -1,22 +1 @@
-import json
-import pytest
-from unittest.mock import patch, MagicMock
-from lambda.app import app, hello, save_item
-
-mock_table = MagicMock()
-mock_table.put_item.return_value = {}
-
-@pytest.fixture
-def mock_dynamodb():
-    with patch('lambda.app.table', mock_table):
-        yield mock_table
-
-def test_hello_default():
-    result = hello()
-    assert result['message'] == 'Hello World from Lambda!'
-
-def test_save_item_success(mock_dynamodb):
-    item = {'id': '123', 'name': 'Test'}
-    result = save_item(item)
-    assert result['status'] == 'saved'
-    mock_dynamodb.put_item.assert_called_once_with(Item=item)
+"""Legacy stub tests removed — see tests/test_exclusao.py (moto + LATEST)."""