Manual del Proveedor REST
A primera vista
Qué: Utilice el proveedor rest integrado para verificaciones de evidencia GET limitadas. Por qué: Controle las reclamaciones de API remotas sin construir un proveedor MCP externo. Quién: Operadores e integradores que crean condiciones respaldadas por REST. Requisitos previos: getting_started.md, condition_authoring.md
Alcance y Garantías
El proveedor REST V1 es intencionalmente limitado:
- SOLO GET
- checks:
json_path,header - validación de solicitud/respuesta que falla en cerrado
- emisión de anclaje de evidencia determinista (
rest_request)
Comportamiento crítico para la seguridad:
json_pathrequiere tipo de contenido JSON (application/jsono*+json)- los encabezados de consulta no pueden anular los encabezados reservados/gestionados por autenticación
- las redirecciones son rechazadas
- se aplican límites de tamaño de respuesta y tiempo de espera
Costura de extensibilidad (para integradores de plataforma):
- OSS runtime exposes
RestPolicyEvaluatorhooks for:- decisiones de host/esquema de salida
- decisiones del esquema de autenticación
- El evaluador OSS predeterminado preserva el comportamiento anterior (permitir).
- Los evaluadores personalizados pueden denegar con códigos de razón deterministas para auditoría/gobernanza.
Configuración del Proveedor
Registro mínimo incorporado:
[[providers]]
name = "rest"
type = "builtin"
config = { allow_http = false, timeout_ms = 5000, max_response_bytes = 1048576, allowed_hosts = ["api.example.com"], allow_private_networks = false, user_agent = "decision-gate/0.1", hash_algorithm = "sha256" }
Con autenticación y encabezados predeterminados:
[[providers]]
name = "rest"
type = "builtin"
allow_raw = true
config = { allow_http = false, timeout_ms = 5000, max_response_bytes = 1048576, allowed_hosts = ["api.example.com"], allow_private_networks = false, user_agent = "decision-gate/0.1", hash_algorithm = "sha256", auth = { bearer_token = "${env:API_TOKEN}" }, default_headers = { x_dg_client = "decision-gate" } }
Ejemplo de validación de configuración:
[server]
transport = "http"
bind = "127.0.0.1:4000"
mode = "strict"
[server.auth]
mode = "local_only"
[namespace]
allow_default = true
default_tenants = [1]
[trust]
default_policy = "audit"
min_lane = "verified"
[evidence]
allow_raw_values = true
require_provider_opt_in = true
[schema_registry]
type = "sqlite"
path = "decision-gate-registry.db"
[schema_registry.acl]
allow_local_only = true
require_signing = false
[run_state_store]
type = "sqlite"
path = "decision-gate.db"
journal_mode = "wal"
sync_mode = "full"
busy_timeout_ms = 5000
[[providers]]
name = "time"
type = "builtin"
[[providers]]
name = "env"
type = "builtin"
[[providers]]
name = "json"
type = "builtin"
config = { root = "./evidence", root_id = "evidence-root", max_bytes = 1048576, allow_yaml = true }
[[providers]]
name = "http"
type = "builtin"
[[providers]]
name = "rest"
type = "builtin"
allow_raw = true
config = { allow_http = true, timeout_ms = 5000, max_response_bytes = 1048576, allowed_hosts = ["127.0.0.1"], allow_private_networks = true, user_agent = "decision-gate/0.1", hash_algorithm = "sha256" }
Ejemplos de Condiciones
json_path condición:
{
"condition_id": "remote_approved",
"query": {
"provider_id": "rest",
"check_id": "json_path",
"params": {
"url": "https://api.example.com/decision/42",
"jsonpath": "$.approved",
"headers": { "x-client": "dg" }
}
},
"comparator": "equals",
"expected": true,
"policy_tags": []
}
header condición:
{
"condition_id": "remote_etag_present",
"query": {
"provider_id": "rest",
"check_id": "header",
"params": {
"url": "https://api.example.com/decision/42",
"header_name": "etag"
}
},
"comparator": "exists",
"expected": null,
"policy_tags": []
}
Consulta de Evidencia Ejecutable
Este bloque inicia un fixture HTTP local, llama a evidence_query contra el proveedor rest, y afirma los campos de determinismo de valor + ancla.
import json
import os
import threading
from http.server import BaseHTTPRequestHandler
from http.server import HTTPServer
from urllib import request
class Handler(BaseHTTPRequestHandler):
def do_GET(self) -> None:
if self.path != "/decision":
self.send_response(404)
self.end_headers()
return
body = json.dumps({"approved": True, "summary": {"count": 7}}).encode("utf-8")
self.send_response(200)
self.send_header("Content-Type", "application/json")
self.send_header("Content-Length", str(len(body)))
self.end_headers()
self.wfile.write(body)
def log_message(self, _format: str, *_args: object) -> None:
return
def call_tool(endpoint: str, tool_name: str, arguments: dict) -> dict:
payload = {
"jsonrpc": "2.0",
"id": 1,
"method": "tools/call",
"params": {"name": tool_name, "arguments": arguments},
}
req = request.Request(
endpoint,
data=json.dumps(payload).encode("utf-8"),
headers={"Content-Type": "application/json"},
method="POST",
)
with request.urlopen(req, timeout=10) as resp:
body = json.loads(resp.read().decode("utf-8"))
if "error" in body:
raise RuntimeError(f"tool call failed: {body['error']}")
content = body.get("result", {}).get("content", [])
if not content or "json" not in content[0]:
raise RuntimeError(f"unexpected tool result envelope: {body}")
return content[0]["json"]
server = HTTPServer(("127.0.0.1", 0), Handler)
thread = threading.Thread(target=server.serve_forever, daemon=True)
thread.start()
try:
endpoint = os.environ.get("DG_ENDPOINT", "http://127.0.0.1:8080/rpc")
fixture_url = f"http://127.0.0.1:{server.server_port}/decision"
response = call_tool(
endpoint,
"evidence_query",
{
"query": {
"provider_id": "rest",
"check_id": "json_path",
"params": {"url": fixture_url, "jsonpath": "$.approved"},
},
"context": {
"tenant_id": 1,
"namespace_id": 1,
"run_id": "docs-run-1",
"scenario_id": "docs-scenario",
"stage_id": "main",
"trigger_id": "docs-trigger-1",
"trigger_time": {"kind": "logical", "value": 1},
"correlation_id": None,
},
},
)
result = response["result"]
assert result["error"] is None, result
assert result["value"] == {"kind": "json", "value": True}, result
anchor = result["evidence_anchor"]
assert anchor["anchor_type"] == "rest_request", anchor
anchor_value = json.loads(anchor["anchor_value"])
assert anchor_value["check_id"] == "json_path", anchor_value
assert "response_body_hash" in anchor_value, anchor_value
finally:
server.shutdown()
thread.join(timeout=5)
Notas
- Utiliza
evidence_querypara la depuración a nivel de proveedor y la inspección de errores deterministas. - Para los resultados de la puerta, ejecuta
scenario_nexte inspecciona los artefactos de runpack cuando sea necesario. - Prefiera listas de permitidos de host explícitas y mantenga
allow_private_networks = falsea menos que sea necesario.