# body-malformed

The body of the request is **not a JSON object of the expected shape**.

- **Status:** `400 Bad Request`
- **Routes:** `POST /api/v1/generate-events`, `QUERY /api/v1/read-data-set`, `QUERY /api/v1/read-domains`
- **Description:**
    - for `generate-events`: `body is malformed: expected a JSON object with domain, scenario, range, eventCount, seed, and format`
    - for `read-data-set`: `body is malformed: expected a JSON object with name and format`
    - for `read-domains`: `body is malformed: expected an empty JSON object`
- **Details:** Empty, or **`field`**, the field to blame, by its path from the root of the body, such as `eventTypePrefix` or `range.until`.

## Why It Happens

- The body is **not JSON**, or not a **single JSON object**, such as an array, `null`, or two objects in a row.
- The body has a **field that SynthEvents does not know**. Field names are case-sensitive, so `eventcount` is unknown. A request names no event type prefix, so `eventTypePrefix` is unknown, too. If there are several unknown fields, `field` names one of them.
- A value has the **wrong type**, such as `eventCount` given as the string `"5000"` rather than as a number, or `range` given as a string rather than as an object. `field` names it.
- For `read-data-set`, the body has a field other than `name` and `format`, such as `seed`: a ready-made data set has its seed already.
- For `read-domains`, the body has **any field at all**. It has to be exactly `{}`.

## How to Fix It

For `generate-events`, send a single JSON object with exactly the fields `domain`, `scenario`, `range` with `from` and `to`, `eventCount`, `seed`, and `format`, each of them with a value of its type (see **[API](/docs/synthevents/api#generating-events)**). For `read-data-set`, send a JSON object with exactly the fields `name` and `format`, both strings (see **[API](/docs/synthevents/api#reading-ready-made-data-sets)**). For `read-domains`, send `{}`.

## Example

For a request to `generate-events` with the field `eventTypePrefix`, SynthEvents answers:

```json
{
  "type": "error",
  "data": {
    "code": "https://docs.synthevents.io/errors/body-malformed",
    "description": "body is malformed: expected a JSON object with domain, scenario, range, eventCount, seed, and format",
    "details": {
      "field": "eventTypePrefix"
    }
  }
}
```