State Persistence

from polos import WorkflowState

class ShoppingCartState(WorkflowState):
    items: list[dict] = []
    total: float = 0.0

import { z } from 'zod';

const ShoppingCartStateSchema = z.object({
  items: z.array(z.record(z.unknown())).default([]),
  total: z.number().default(0),
});

type ShoppingCartState = z.infer<typeof ShoppingCartStateSchema>;

from polos import workflow, WorkflowContext

@workflow(id="shopping_cart", state_schema=ShoppingCartState)
async def shopping_cart(ctx: WorkflowContext, payload: CartPayload):
    if payload.action == "add" and payload.item:
        ctx.state.items.append(payload.item.model_dump())
        ctx.state.total += payload.item.price * payload.item.quantity

    elif payload.action == "remove" and payload.item_id:
        for i, item in enumerate(ctx.state.items):
            if item.get("id") == payload.item_id:
                ctx.state.total -= item["price"] * item["quantity"]
                ctx.state.items.pop(i)
                break

    elif payload.action == "clear":
        ctx.state.items = []
        ctx.state.total = 0.0

    return {"items": ctx.state.items, "total": ctx.state.total}

import { defineWorkflow } from '@polos/sdk';

const shoppingCartWorkflow = defineWorkflow<CartPayload, ShoppingCartState, CartResult>(
  { id: 'shopping_cart', stateSchema: ShoppingCartStateSchema },
  async (ctx, payload) => {
    if (payload.action === 'add' && payload.item) {
      ctx.state.items.push({
        id: payload.item.id,
        name: payload.item.name,
        price: payload.item.price,
        quantity: payload.item.quantity,
      });
      ctx.state.total += payload.item.price * payload.item.quantity;
    } else if (payload.action === 'remove' && payload.itemId) {
      const idx = ctx.state.items.findIndex((item) => item['id'] === payload.itemId);
      if (idx >= 0) {
        const item = ctx.state.items[idx]!;
        ctx.state.total -= (Number(item['price']) || 0) * (Number(item['quantity']) || 1);
        ctx.state.items.splice(idx, 1);
      }
    } else if (payload.action === 'clear') {
      ctx.state.items = [];
      ctx.state.total = 0;
    }

    return { items: ctx.state.items, total: ctx.state.total };
  },
);

# Start workflow with initial state
handle = await polos.invoke(
    "shopping_cart",
    payload={"action": "add", "item": {...}},
    initial_state={"items": [], "total": 0.0},
)

// Start workflow with initial state
const handle = await polos.invoke(
  'shopping_cart',
  { action: 'add', item: { /* ... */ } },
  { initialState: { items: [], total: 0 } },
);

git clone https://github.com/polos-dev/polos.git
cd polos/python-examples/10-state-persistence
cp .env.example .env  # Add your POLOS_PROJECT_ID and API key
uv sync
python main.py

git clone https://github.com/polos-dev/polos.git
cd polos/typescript-examples/10-state-persistence
cp .env.example .env  # Add your POLOS_PROJECT_ID and API key
npm install
npx tsx main.ts