# iceberg-js
[](https://github.com/supabase/iceberg-js/actions/workflows/ci.yml)
[](https://www.npmjs.com/package/iceberg-js)
[](https://pkg.pr.new/~/supabase/iceberg-js)
A small, framework-agnostic JavaScript/TypeScript client for the **Apache Iceberg REST Catalog**.
## Features
- **Generic**: Works with any Iceberg REST Catalog implementation, not tied to any specific vendor
- **Minimal**: Thin HTTP wrapper over the official REST API, no engine-specific logic
- **Type-safe**: First-class TypeScript support with strongly-typed request/response models
- **Fetch-based**: Uses native `fetch` API with support for custom implementations
- **Universal**: Targets Node 20+ and modern browsers (ES2020)
- **Catalog-only**: Focused on catalog operations (no data reading/Parquet support in v0.1.0)
## Documentation
📚 **Full API documentation**: [supabase.github.io/iceberg-js](https://supabase.github.io/iceberg-js/)
## Installation
```bash
npm install iceberg-js
```
## Quick Start
```typescript
import { IcebergRestCatalog } from 'iceberg-js'
const catalog = new IcebergRestCatalog({
baseUrl: 'https://my-catalog.example.com/iceberg/v1',
auth: {
type: 'bearer',
token: process.env.ICEBERG_TOKEN,
},
})
// Create a namespace
await catalog.createNamespace({ namespace: ['analytics'] })
// Create a table
await catalog.createTable(
{ namespace: ['analytics'] },
{
name: 'events',
schema: {
type: 'struct',
fields: [
{ id: 1, name: 'id', type: 'long', required: true },
{ id: 2, name: 'timestamp', type: 'timestamp', required: true },
{ id: 3, name: 'user_id', type: 'string', required: false },
],
'schema-id': 0,
'identifier-field-ids': [1],
},
'partition-spec': {
'spec-id': 0,
fields: [],
},
'write-order': {
'order-id': 0,
fields: [],
},
properties: {
'write.format.default': 'parquet',
},
}
)
```
## API Reference
### Constructor
#### `new IcebergRestCatalog(options)`
Creates a new catalog client instance.
**Options:**
- `baseUrl` (string, required): Base URL of the REST catalog
- `auth` (AuthConfig, optional): Authentication configuration
- `catalogName` (string, optional): Catalog name for multi-catalog servers. When specified, requests are sent to `{baseUrl}/v1/{catalogName}/...`. For example, with `baseUrl: 'https://host.com'` and `catalogName: 'prod'`, requests go to `https://host.com/v1/prod/namespaces`
- `fetch` (typeof fetch, optional): Custom fetch implementation
- `accessDelegation` (AccessDelegation[], optional): Access delegation mechanisms to request from the server
**Authentication types:**
```typescript
// No authentication
{ type: 'none' }
// Bearer token
{ type: 'bearer', token: 'your-token' }
// Custom header
{ type: 'header', name: 'X-Custom-Auth', value: 'secret' }
// Custom function
{ type: 'custom', getHeaders: async () => ({ 'Authorization': 'Bearer ...' }) }
```
**Access Delegation:**
Access delegation allows the catalog server to provide temporary credentials or sign requests on your behalf:
```typescript
import { IcebergRestCatalog } from 'iceberg-js'
const catalog = new IcebergRestCatalog({
baseUrl: 'https://catalog.example.com/iceberg/v1',
auth: { type: 'bearer', token: 'your-token' },
// Request vended credentials for data access
accessDelegation: ['vended-credentials'],
})
// The server may return temporary credentials in the table metadata
const metadata = await catalog.loadTable({ namespace: ['analytics'], name: 'events' })
// Use credentials from metadata.config to access table data files
```
Supported delegation mechanisms:
- `vended-credentials`: Server provides temporary credentials (e.g., AWS STS tokens) for accessing table data
- `remote-signing`: Server signs data access requests on behalf of the client
### Namespace Operations
#### `listNamespaces(parent?: NamespaceIdentifier): Promise<NamespaceIdentifier[]>`
List all namespaces, optionally under a parent namespace.
```typescript
const namespaces = await catalog.listNamespaces()
// [{ namespace: ['default'] }, { namespace: ['analytics'] }]
const children = await catalog.listNamespaces({ namespace: ['analytics'] })
// [{ namespace: ['analytics', 'prod'] }]
```
#### `createNamespace(id: NamespaceIdentifier, metadata?: NamespaceMetadata): Promise<void>`
Create a new namespace with optional properties.
```typescript
await catalog.createNamespace({ namespace: ['analytics'] }, { properties: { owner: 'data-team' } })
```
#### `dropNamespace(id: NamespaceIdentifier): Promise<void>`
Drop a namespace. The namespace must be empty.
```typescript
await catalog.dropNamespace({ namespace: ['analytics'] })
```
#### `loadNamespaceMetadata(id: NamespaceIdentifier): Promise<NamespaceMetadata>`
Load namespace metadata and properties.
```typescript
const metadata = await catalog.loadNamespaceMetadata({ namespace: ['analytics'] })
// { properties: { owner: 'data-team', ... } }
```
### Table Operations
#### `listTables(namespace: NamespaceIdentifier): Promise<TableIdentifier[]>`
List all tables in a namespace.
```typescript
const tables = await catalog.listTables({ namespace: ['analytics'] })
// [{ namespace: ['analytics'], name: 'events' }]
```
#### `createTable(namespace: NamespaceIdentifier, request: CreateTableRequest): Promise<TableMetadata>`
Create a new table.
```typescript
const metadata = await catalog.createTable(
{ namespace: ['analytics'] },
{
name: 'events',
schema: {
type: 'struct',
fields: [
{ id: 1, name: 'id', type: 'long', required: true },
{ id: 2, name: 'timestamp', type: 'timestamp', required: true },
],
'schema-id': 0,
},
'partition-spec': {
'spec-id': 0,
fields: [
{
source_id: 2,
field_id: 1000,
name: 'ts_day',
transform: 'day',
},
],
},
}
)
```
#### `loadTable(id: TableIdentifier): Promise<TableMetadata>`
Load table metadata.
```typescript
const metadata = await catalog.loadTable({
namespace: ['analytics'],
name: 'events',
})
```
#### `updateTable(id: TableIdentifier, request: UpdateTableRequest): Promise<TableMetadata>`
Update table metadata (schema, partition spec, or properties).
```typescript
const updated = await catalog.updateTable(
{ namespace: ['analytics'], name: 'events' },
{
properties: { 'read.split.target-size': '134217728' },
}
)
```
#### `dropTable(id: TableIdentifier): Promise<void>`
Drop a table from the catalog.
```typescript
await catalog.dropTable({ namespace: ['analytics'], name: 'events' })
```
## Error Handling
All API errors throw an `IcebergError` with details from the server:
```typescript
import { IcebergError } from 'iceberg-js'
try {
await catalog.loadTable({ namespace: ['test'], name: 'missing' })
} catch (error) {
if (error instanceof IcebergError) {
console.log(error.status) // 404
console.log(error.icebergType) // 'NoSuchTableException'
console.log(error.message) // 'Table does not exist'
}
}
```
## TypeScript Types
The library exports all relevant types:
```typescript
import type {
NamespaceIdentifier,
TableIdentifier,
TableSchema,
TableField,
IcebergType,
PartitionSpec,
SortOrder,
CreateTableRequest,
TableMetadata,
AuthConfig,
AccessDelegation,
} from 'iceberg-js'
```
## Supported Iceberg Types
The following Iceberg primitive types are supported:
- `boolean`, `int`, `long`, `float`, `double`
- `string`, `uuid`, `binary`
- `date`, `time`, `timestamp`, `timestamptz`
- `decimal(precision, scale)`, `fixed(length)`
## Compatibility
This package is built to work in **all** Node.js and JavaScript environments:
| Environment | Module System | Import Method | Status |
| ------------------- | -------------------- | --------------------------------------- | --------------------- |
| Node.js ESM | `"type": "module"` | `import { ... } from 'iceberg-js'` | ✅ Fully supported |
| Node.js CommonJS | Default | `const { ... } = require('iceberg-js')` | ✅ Fully supported |
| TypeScript ESM | `module: "ESNext"` | `import { ... } from 'iceberg-js'` | ✅ Full type support |
| TypeScript CommonJS | `module: "CommonJS"` | `import { ... } from 'iceberg-js'` | ✅ Full type support |
| Bundlers | Any | Webpack, Vite, esbuild, Rollup, etc. | ✅ Auto-detected |
| Browsers | ESM | `<script type="module">` | ✅ Modern browsers |
| Deno | ESM | `import` from npm: | ✅ With npm specifier |
**Package exports:**
- ESM: `dist/index.mjs` with `dist/index.d.ts`
- CommonJS: `dist/index.cjs` with `dist/index.d.cts`
- Proper `exports` field for Node.js 12+ module resolution
All scenarios are tested in CI on Node.js 20 and 22.
## Browser Usage
The library works in modern browsers that support native `fetch`:
```typescript
import { IcebergRestCatalog } from 'iceberg-js'
const catalog = new IcebergRestCatalog({
baseUrl: 'https://public-catalog.example.com/iceberg/v1',
auth: { type: 'none' },
})
const namespaces = await catalog.listNamespaces()
```
## Node.js Usage
Node.js 20+ includes native `fetch` support. For older versions, provide a custom fetch implementation:
```typescript
import { IcebergRestCatalog } from 'iceberg-js'
import fetch from 'node-fetch'
const catalog = new IcebergRestCatalog({
baseUrl: 'https://catalog.example.com/iceberg/v1',
auth: { type: 'bearer', token: 'token' },
fetch: fetch as any,
})
```
## Limitations (v0.1.0)
This is a catalog client only. The following are **not supported**:
- Reading table data (scanning Parquet files)
- Writing data to tables
- Advanced table operations (commits, snapshots, time travel)
- Views support
- Multi-table transactions
## Development
```bash
# Install dependencies
pnpm install
# Build the library
pnpm run build
# Run unit tests
pnpm test
# Run integration tests (requires Docker)
pnpm test:integration
# Run integration tests with cleanup (for CI)
pnpm test:integration:ci
# Run compatibility tests (all module systems)
pnpm test:compatibility
# Format code
pnpm run format
# Lint and test
pnpm run check
```
### Testing with Docker
Integration tests run against a local Iceberg REST Catalog in Docker. See [TESTING-DOCKER.md](./test/integration/TESTING-DOCKER.md) for details.
```bash
# Start Docker services and run integration tests
pnpm test:integration
# Or manually
docker compose up -d
npx tsx test/integration/test-local-catalog.ts
docker compose down -v
```
### Compatibility Testing
The `test:compatibility` script verifies the package works correctly in all JavaScript/TypeScript environments:
- **Pure JavaScript ESM** - Projects with `"type": "module"`
- **Pure JavaScript CommonJS** - Traditional Node.js projects
- **TypeScript ESM** - TypeScript with `module: "ESNext"`
- **TypeScript CommonJS** - TypeScript with `module: "CommonJS"`
These tests ensure proper module resolution, type definitions, and runtime behavior across all supported environments. See [test/compatibility/README.md](./test/compatibility/README.md) for more details.
## License
MIT
## Releases
This project uses [release-please](https://github.com/googleapis/release-please) for automated releases. Here's how it works:
1. **Commit with conventional commits**: Use [Conventional Commits](https://www.conventionalcommits.org/) format for your commits:
- `feat:` for new features (minor version bump)
- `fix:` for bug fixes (patch version bump)
- `feat!:` or `BREAKING CHANGE:` for breaking changes (major version bump)
- `chore:`, `docs:`, `test:`, etc. for non-release commits
2. **Release PR is created automatically**: When you push to `main`, release-please creates/updates a release PR with:
- Version bump in `package.json`
- Updated `CHANGELOG.md`
- Release notes
3. **Merge the release PR**: When you're ready to release, merge the PR. This will:
- Create a GitHub release and git tag
- Automatically publish to npm with provenance (using trusted publishing, no secrets needed)
**Example commits:**
```bash
git commit -m "feat: add support for view operations"
git commit -m "fix: handle empty namespace list correctly"
git commit -m "feat!: change auth config structure"
```
## Contributing
Contributions are welcome! This library aims to be a minimal, generic client for the Iceberg REST Catalog API.
