# JSON Schema Validation

Atmos supports [JSON Schema](https://json-schema.org/) validation, which can validate the schema of configurations such as stacks, workflows, and vendoring manifests.
JSON Schema is an industry standard and provides a vocabulary to annotate and validate JSON documents for correctness.

## Example

```shell
# Validate 'vpc' component using JSON Schema in the 'plat-ue2-prod' stack
atmos validate component vpc -s plat-ue2-prod --schema-path vpc/validate-vpc-component.json --schema-type jsonschema
```

### Configure Component Validation

In [`atmos.yaml`](https://github.com/cloudposse/atmos/blob/main/examples/quick-start-advanced/rootfs/usr/local/etc/atmos/atmos.yaml), add the `schemas`
section:

**File:** `atmos.yaml`

```yaml
# Validation schemas (for validating atmos stacks and components)
schemas:
  # https://json-schema.org
  jsonschema:
    # Can also be set using `ATMOS_SCHEMAS_JSONSCHEMA_BASE_PATH` ENV var, or `--schemas-jsonschema-dir` command-line arguments
    # Supports both absolute and relative paths
    base_path: "stacks/schemas/jsonschema"
```

In the component [manifest](https://github.com/cloudposse/atmos/blob/main/examples/quick-start-advanced/stacks/catalog/vpc/defaults.yaml), add
the `settings.validation` section:

Add the following JSON Schema in the
file [`stacks/schemas/jsonschema/vpc/validate-vpc-component.json`](https://github.com/cloudposse/atmos/blob/main/examples/quick-start-advanced/stacks/schemas/jsonschema/vpc/validate-vpc-component.json):

## Try It

Explore a working example that demonstrates JSON Schema validation in action.