# WeaselDB Configuration

WeaselDB uses a TOML configuration file to control server behavior and API limits. The configuration is organized into three main sections that correspond to different aspects of the system.

## Configuration File Location

By default, WeaselDB looks for `config.toml` in the current directory. You can specify an alternative path:

```bash
./weaseldb /path/to/custom/config.toml
```

## Configuration Sections

### Server Configuration (`[server]`)

Controls basic server binding and request limits.

| Parameter | Type | Default | Description |
|-----------|------|---------|-------------|
| `bind_address` | string | `"127.0.0.1"` | IP address to bind the server to |
| `port` | integer | `8080` | Port number to listen on |
| `max_request_size_bytes` | integer | `1048576` (1MB) | Maximum size for incoming requests. Requests exceeding this limit receive a `413 Content Too Large` response |

### Commit Configuration (`[commit]`)

Controls behavior of the `/v1/commit` endpoint and request ID management.

| Parameter | Type | Default | Description |
|-----------|------|---------|-------------|
| `min_request_id_length` | integer | `20` | Minimum length required for client-provided `request_id` fields to ensure sufficient entropy for collision avoidance |
| `request_id_retention_hours` | integer | `24` | How long to retain request IDs in memory for `/v1/status` queries. Longer retention reduces the chance of `log_truncated` responses |
| `request_id_retention_versions` | integer | `100000000` | Minimum number of versions to retain request IDs for, regardless of time. Provides additional protection against `log_truncated` responses |

### Subscription Configuration (`[subscription]`)

Controls behavior of the `/v1/subscribe` endpoint and SSE streaming.

| Parameter | Type | Default | Description |
|-----------|------|---------|-------------|
| `max_buffer_size_bytes` | integer | `10485760` (10MB) | Maximum amount of unconsumed data to buffer for slow subscribers. Connections are closed if this limit is exceeded |
| `keepalive_interval_seconds` | integer | `30` | Interval between keepalive comments in the Server-Sent Events stream to prevent idle timeouts on network proxies |

## Example Configuration

```toml
# WeaselDB Configuration File

[server]
bind_address = "0.0.0.0"
port = 8080
max_request_size_bytes = 2097152  # 2MB

[commit]
min_request_id_length = 32
request_id_retention_hours = 48
request_id_retention_versions = 50000

[subscription]
max_buffer_size_bytes = 52428800  # 50MB
keepalive_interval_seconds = 15
```

## Configuration Loading

- If the specified config file doesn't exist or contains errors, WeaselDB will use default values and log a warning
- All configuration parameters are optional - any missing values will use the defaults shown above

## API Relationship

These configuration parameters directly affect API behavior:

- **`max_request_size_bytes`**: Determines when `/v1/commit` returns `413 Content Too Large`
- **`min_request_id_length`**: Validates `request_id` fields in `/v1/commit` requests
- **`request_id_retention_*`**: Affects availability of data for `/v1/status` queries and likelihood of `log_truncated` responses
- **`max_buffer_size_bytes`**: Controls when `/v1/subscribe` connections are terminated due to slow consumption
- **`keepalive_interval_seconds`**: Frequency of keepalive comments in `/v1/subscribe` streams