# Validate in your editor

> Plug the published schema of flexway.yaml into your editor: every key completed and a mistake underlined as you type, rather than at start.

Guide - Since version 1.7.0 - Flexway v1.7.1 - https://flexway.io/en/docs/operations-editor-validation/

> Operations guide: configure, deploy and observe the gateway. What the feature does, product side: [product guide](https://flexway.io/en/docs/product-overview/); calling it: [developer guide](https://flexway.io/en/docs/developer-overview/).

Have your editor complete `flexway.yaml` and underline a mistake **as you type** - an
unknown key, a value outside the list, a malformed duration, a secret written in clear - rather than at
start.

Flexway publishes a **JSON Schema** (2020-12) of its configuration, written from the gateway's model
at every version: each key with its type, allowed values, default, the version that brought it,
whether a reload applies it, and a description in English and in French. Key by key:
[configuration reference](https://flexway.io/en/docs/operations-configuration-reference/).

## Steps

1. Add one line at the top of `flexway.yaml` - it is enough for the editors built on
   `yaml-language-server` (VS Code with Red Hat's YAML extension, Neovim, JetBrains, Helix):

```yaml title="flexway.yaml"
# yaml-language-server: $schema=https://flexway.io/schema/v1/flexway.schema.json
version: 1
contracts:
  openapi: ./openapi.yaml
upstreams:
  orders:
    url: http://orders.internal:8080
    timeout: 3s
```

2. Offline, or to pin the schema of the version you deploy, write it from that version's image:

```bash
docker run --rm -v "$PWD:/out" -u "$(id -u)" ghcr.io/flexwiz/flexway:<version> schema --out /out
# /out/flexway.schema.json
# /out/contract-extensions.schema.json
# /out/policy-fragment.schema.json       (a fragment file, kind: PolicyFragment)
```

3. Point the line at the local file: `# yaml-language-server: $schema=./flexway.schema.json`.

### Contract extensions

The `x-flexway-*` extensions of an OpenAPI or AsyncAPI document or of an A2A card are
described by `contract-extensions.schema.json` (one definition per extension under `$defs`, with the
places it is read at). Policies are in `flexway.schema.json`: the shape of `config` follows the
definition's `type` (`cors`, `rate-limit`, `quota`, `cache`, `header-inject`, `header-remove`,
`rewrite-path`, `query-inject`, `query-remove`, `transform-body`, `redact`, `map-status`,
`external-call`).

## Verify

Write `timeouts: { conect: 5s }` under `server` - the editor underlines `conect` (an
unknown key); completion offers `connect` with its description and its default `5s`. Write `log_level: verbose` under
`observability` - the editor lists `debug`, `info`, `warn`, `error`, `fatal`.

## Good to know

> [!IMPORTANT]
> The schema **describes**; `flexway validate` **decides**. What spans several files - an upstream for
> every operation of the contract, a route declared twice, a named policy that does not exist - is
> checked only by `flexway validate` and at start. Keep `flexway validate` in your CI.