# Project file schemas

[`wai-json-1.schema.json`](wai-json-1.schema.json) is the JSON Schema of `wai.json`, a WAI
project file, version 1 (JSON Schema 2020-12). Its `$id`, and the `$schema` member every project
file `wai create` writes names, is `https://wai.transaction.science/schema/wai.json/1`, the
address it is to be served from. The release of `wai` waits for it: the tag build
(`.github/workflows/wai-release.yml`) fails while that address does not serve this file, so no
release writes a project file that names a schema an editor or an agent cannot fetch.

`wai/wai-rs/src/bin/wai_cli/dx/project.rs` is the reader. Its tests hold this file to it: the
same members in the file and in its `dev` block, the same modes, the same name rule, and the
same verdict, accept or refuse, on every template's project file and on a set of files each
breaking one rule. A change to either is a change to both.

## Versions

Version 1 stays open until the first release of `wai` that writes it. From that release on, its
readers are in use, and a reader refuses any member it does not know, so version 1 does not
change: a member added to it would be refused, as unknown, by every reader of that release. A
later version is a new schema at `…/schema/wai.json/<version>`, beside this one. A reader
refuses a file of a later version as that version (`upgrade wai`), by its `wai` member or by its
`$schema`, before it reads any other member, so the members the later version adds never stop
it first.

The project file's other members in the toolchain's design (`requires`, `room`, `package`,
`conform`, `breaking`, `targets`, `receipts`, and `port` in `dev`) are version 2's. Each joins
the file with the operation that reads it, as every member of version 1 has its reader; a member
accepted with nothing to read it would be one the strict reader ignores, which is what it
refuses to do.