GET history endpoint

Makefile

@@ -4,7 +4,7 @@ install:
 
 # Installs development dependencies
 install-dev:
-	pip install .[dev];
+	pip install ".[dev]";
 
 lock:
 	pip freeze --exclude guardrails-api-client > requirements-lock.txt

guardrails_api/app.py

@@ -9,6 +9,7 @@
 from opentelemetry.instrumentation.flask import FlaskInstrumentor
 from guardrails_api.clients.postgres_client import postgres_is_enabled
 from guardrails_api.otel import otel_is_disabled, initialize
+from guardrails_api.clients.cache_client import CacheClient
 
 
 # TODO: Move this to a separate file
@@ -80,6 +81,9 @@ def create_app(env: Optional[str] = None, config: Optional[str] = None):
 
         pg_client = PostgresClient()
         pg_client.initialize(app)
+
+    cache_client = CacheClient()
+    cache_client.initialize(app)
 
     from guardrails_api.blueprints.root import root_bp
     from guardrails_api.blueprints.guards import guards_bp

guardrails_api/blueprints/guards.py

@@ -10,6 +10,7 @@
 from opentelemetry.trace import Span
 from guardrails_api_client import Guard as GuardStruct
 from guardrails_api.classes.http_error import HttpError
+from guardrails_api.clients.cache_client import CacheClient
 from guardrails_api.clients.memory_guard_client import MemoryGuardClient
 from guardrails_api.clients.pg_guard_client import PGGuardClient
 from guardrails_api.clients.postgres_client import postgres_is_enabled
@@ -34,6 +35,8 @@
         is_guard = isinstance(export, Guard)
         if is_guard:
             guard_client.create_guard(export)
+
+cache_client = CacheClient()
 
 
 @guards_bp.route("/", methods=["GET", "POST"])
@@ -308,4 +311,16 @@ def validate_streamer(guard_iter):
     #     prompt_params=prompt_params,
     #     result=result
     # )
+    serialized_history = [
+        call.to_dict() for call in guard.history
+    ]
+    cache_key = f"{guard.name}-{result.call_id}"
+    cache_client.set(cache_key, serialized_history, 300)
     return result.to_dict()
+
+@guards_bp.route("/<guard_name>/history/<call_id>", methods=["GET"])
+@handle_error
+def guard_history(guard_name: str, call_id: str):
+    if request.method == "GET":
+        cache_key = f"{guard_name}-{call_id}"
+        return cache_client.get(cache_key)

guardrails_api/clients/cache_client.py

@@ -0,0 +1,35 @@
+from flask_caching import Cache
+
+
+# TODO: Add option to connect to Redis or MemCached backend with environment variables
+class CacheClient:
+    _instance = None
+
+    def __new__(cls):
+        if cls._instance is None:
+            cls._instance = super(CacheClient, cls).__new__(cls)
+        return cls._instance
+
+
+    def initialize(self, app):
+        self.cache = Cache(
+            app, 
+            config={
+                "CACHE_TYPE": "simple",
+                "CACHE_DEFAULT_TIMEOUT": 300,
+                "CACHE_NO_NULL_WARNING": True,
+                "CACHE_THRESHOLD": 50
+            }
+        )
+
+    def get(self, key):
+        return self.cache.get(key)
+
+    def set(self, key, value, ttl):
+        self.cache.set(key, value, timeout=ttl)
+
+    def delete(self, key):
+        self.cache.delete(key)
+
+    def clear(self):
+        self.cache.clear()

pyproject.toml

@@ -10,9 +10,10 @@ readme = "README.md"
 keywords = ["Guardrails", "Guardrails AI", "Guardrails API", "Guardrails API"]
 requires-python = ">= 3.8.1"
 dependencies = [
-    "guardrails-ai@git+https://github.com/guardrails-ai/guardrails.git@core-schema-impl",
+    "guardrails-ai@git+https://github.com/guardrails-ai/guardrails.git@0.5.0-dev",
     "flask>=3.0.3,<4",
     "Flask-SQLAlchemy>=3.1.1,<4",
+    "Flask-Caching>=2.3.0,<3",
     "Werkzeug>=3.0.3,<4",
     "jsonschema>=4.22.0,<5",
     "referencing>=0.35.1,<1",