Type System Deep Dive

const users = container('users', {
  id: field.string(),
  email: field.string(),
  name: field.string().optional(),
  age: field.number()
}).partitionKey('email');

// The type is automatically inferred:
type User = typeof users.infer;
// {
//   id: string;
//   email: string;
//   name?: string;
//   age: number;
// }

// Query results are typed automatically
const user = await db.users.findUnique({
  where: { id: '123', email: 'john@example.com' }
});
// Type: User | null (no manual type annotation needed!)

// Select creates a new type
const partial = await db.users.findUnique({
  where: { id: '123', email: 'john@example.com' },
  select: { name: true, age: true }
});
// Type: { name?: string; age: number } | null

// Missing partition key
const user = await db.users.findUnique({
  where: { id: '123' }
});

// Error message in IDE:
// ❌ PARTITION KEY REQUIRED
//
// This operation requires a partition key to avoid expensive cross-partition queries.
//
// 💡 Fix: Add the partition key to your where clause:
//    where: { id: '123', email: 'john@example.com' }
//
// 📖 Learn more about partition keys: https://cosmosql.dev/docs/partition-keys

import { isCosmosError } from 'cosmosql';

try {
  await db.users.create({ data: user });
} catch (error) {
  if (isCosmosError(error)) {
    // error is now typed as CosmosError
    console.log(error.code, error.statusCode, error.retryAfter);
  }
}