Harrison/gr int (#1700)

Co-authored-by: Shreya Rajpal <ShreyaR@users.noreply.github.com>

langchain/output_parsers/__init__.py

@@ -3,6 +3,7 @@ from langchain.output_parsers.list import (
     CommaSeparatedListOutputParser,
     ListOutputParser,
 )
+from langchain.output_parsers.rail_parser import GuardrailsOutputParser
 from langchain.output_parsers.regex import RegexParser
 from langchain.output_parsers.regex_dict import RegexDictParser
 from langchain.output_parsers.structured import ResponseSchema, StructuredOutputParser
@@ -15,4 +16,5 @@ __all__ = [
     "BaseOutputParser",
     "StructuredOutputParser",
     "ResponseSchema",
+    "GuardrailsOutputParser",
 ]

langchain/output_parsers/rail_parser.py

@@ -0,0 +1,43 @@
+from __future__ import annotations
+
+from typing import Any, Dict
+
+from langchain.output_parsers.base import BaseOutputParser
+
+
+class GuardrailsOutputParser(BaseOutputParser):
+    guard: Any
+
+    @property
+    def _type(self) -> str:
+        return "guardrails"
+
+    @classmethod
+    def from_rail(cls, rail_file: str, num_reasks: int = 1) -> GuardrailsOutputParser:
+        try:
+            from guardrails import Guard
+        except ImportError:
+            raise ValueError(
+                "guardrails-ai package not installed. "
+                "Install it by running `pip install guardrails-ai`."
+            )
+        return cls(guard=Guard.from_rail(rail_file, num_reasks=num_reasks))
+
+    @classmethod
+    def from_rail_string(
+        cls, rail_str: str, num_reasks: int = 1
+    ) -> GuardrailsOutputParser:
+        try:
+            from guardrails import Guard
+        except ImportError:
+            raise ValueError(
+                "guardrails-ai package not installed. "
+                "Install it by running `pip install guardrails-ai`."
+            )
+        return cls(guard=Guard.from_rail_string(rail_str, num_reasks=num_reasks))
+
+    def get_format_instructions(self) -> str:
+        return self.guard.raw_prompt.format_instructions
+
+    def parse(self, text: str) -> Dict:
+        return self.guard.parse(text)