Feat/ext langgraph checkpoint

examples/langgraph-checkpointer/.env.template

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+OPENAI_API_KEY="sk-proj-very-secret-key"

examples/langgraph-checkpointer/README.md

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+# Dapr For Agents - LangGraph Checkpointer
+
+Supporting Dapr backed Checkpointer for LangGraph based Agents.
+
+1. Initialize Dapr
+
+```shell
+dapr init
+```
+
+2. Install dependencies either with
+```shell
+uv sync
+```
+or 
+```shell
+pip install -r requirements.txt
+```
+
+3. Ensure to correct the template file for `.env` with your OpenAI API Key
+
+4. Run the agent
+```shell
+dapr run -f dapr.yaml
+```
+
+This will provision the redis & SQLite state stores (which we use in this example, see `./components/*-memory.yaml`) to store the state, the Checkpointer, for the LangGraph agent to have short term memory. See [State Management](https://docs.dapr.io/developing-applications/building-blocks/state-management/) for more details on State Managenent and [LangGraph - Memory](https://docs.langchain.com/oss/python/langgraph/add-memory) for details on LangGraph Agent Memory.
+
+This example is based on the LangGraph Academy Demo repository for [agent-memory in module-1](https://github.com/langchain-ai/langchain-academy/blob/b20cf608f2bf165e09080961537d329f813cfb20/module-1/agent-memory.ipynb).
+
+## Inspect
+
+After running you'll find `./data.db`.
+
+1. Connect
+```shell
+sqlite3 data.db
+```
+
+2. List tables
+```shell
+.tables
+```
+
+3. Inspect state table
+```shell
+select * from state;
+```
+
+In this example we ran 2 threads that each had their own seperate memory checkpointer and by using dapr it was completely transparent that one was using Redis and the other SQLite DB.

examples/langgraph-checkpointer/components/redis-memory.yaml

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+apiVersion: dapr.io/v1alpha1
+kind: Component
+metadata:
+  name: dapr-redis
+spec:
+  type: state.redis
+  version: v1
+  metadata:
+  - name: redisHost
+    value: localhost:6379

examples/langgraph-checkpointer/components/sqlite-memory.yaml

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+apiVersion: dapr.io/v1alpha1
+kind: Component
+metadata:
+  name: dapr-sqlite
+spec:
+  type: state.sqlite
+  version: v1
+  metadata:
+  - name: connectionString
+    value: "data.db"

examples/langgraph-checkpointer/dapr.yaml

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+version: 1
+common:
+  resourcesPath: ./components
+  logLevel: info
+  appLogDestination: console
+  daprdLogDestination: console
+
+apps:
+- appID: langgraph_app
+  appDirPath: .
+  command: ["python", "main.py"]

examples/langgraph-checkpointer/main.py

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+import os
+
+from dapr.ext.langgraph import DaprCheckpointer
+from dotenv import load_dotenv
+from langchain_core.messages import HumanMessage, SystemMessage
+from langchain_openai import ChatOpenAI
+from langgraph.graph import START, MessagesState, StateGraph
+from langgraph.prebuilt import ToolNode, tools_condition
+
+load_dotenv()
+
+
+def add(a: int, b: int) -> int:
+    """Adds a and b.
+
+    Args:
+        a: first int
+        b: second int
+    """
+    return a + b
+
+
+def multiply(a: int, b: int) -> int:
+    """Multiply a and b.
+
+    Args:
+        a: first int
+        b: second int
+    """
+    return a * b
+
+
+tools = [add, multiply]
+llm = ChatOpenAI(model='gpt-4o', api_key=os.environ['OPENAI_API_KEY'])
+llm_with_tools = llm.bind_tools(tools)
+
+sys_msg = SystemMessage(
+    content='You are a helpful assistant tasked with performing arithmetic on a set of inputs.'
+)
+
+
+def assistant(state: MessagesState):
+    return {'messages': [llm_with_tools.invoke([sys_msg] + state['messages'])]}
+
+
+builder = StateGraph(MessagesState)
+
+builder.add_node('assistant', assistant)
+builder.add_node('tools', ToolNode(tools))
+
+builder.add_edge(START, 'assistant')
+builder.add_conditional_edges(
+    'assistant',
+    tools_condition,
+)
+builder.add_edge('tools', 'assistant')
+
+memory = DaprCheckpointer(store_name='dapr-redis', key_prefix='dapr')
+react_graph_memory = builder.compile(checkpointer=memory)
+
+config = {'configurable': {'thread_id': '1'}}
+
+messages = [HumanMessage(content='Add 3 and 4.')]
+messages = react_graph_memory.invoke({'messages': messages}, config)
+for m in messages['messages']:
+    m.pretty_print()
+
+messages = [HumanMessage(content='Multiply that by 2.')]
+messages = react_graph_memory.invoke({'messages': messages}, config)
+for m in messages['messages']:
+    m.pretty_print()
+
+memory = DaprCheckpointer(store_name='dapr-sqlite', key_prefix='dapr')
+react_graph_memory = builder.compile(checkpointer=memory)
+
+config = {'configurable': {'thread_id': '2'}}
+
+messages = [HumanMessage(content='Add 5 and 6.')]
+messages = react_graph_memory.invoke({'messages': messages}, config)
+for m in messages['messages']:
+    m.pretty_print()
+
+messages = [HumanMessage(content='Multiply that by 3.')]
+messages = react_graph_memory.invoke({'messages': messages}, config)
+for m in messages['messages']:
+    m.pretty_print()

examples/langgraph-checkpointer/pyproject.toml

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+[project]
+name = "langgraph-dapr"
+version = "0.1.0"
+description = "Add your description here"
+readme = "README.md"
+requires-python = ">=3.14"
+dependencies = [
+    "dotenv>=0.9.9",
+    "langchain-core>=1.0.7",
+    "langchain-openai>=1.0.3",
+    "langgraph>=1.0.3",
+    "dapr-ext-langgraph>=1.16.0",
+]

examples/langgraph-checkpointer/requirements.txt

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+dotenv>=0.9.9
+langchain-core>=1.0.7
+langchain-openai>=1.0.3
+langgraph>=1.0.3
+dapr-ext-langgraph>=1.16.0