ssb-schema-validation

Returns a function that takes an ssb message and will check first against version, search for a matching schema, then validate against the correct schema and return truthy or falsey with an errorset.

Here's how to use it:

Organise your schemas in version directories, and draw each set together with an index.js that returns an object which contains all the schemas stores by their name as key e.g. `'post'

Ensure our message declares a verision, else we'll get an error.
`js
{
type: 'post',
version: '1.0.0',
body: 'tra-lala-lala-lala'
}
`

And export a schema for each version.

Example project structure could look like this...

`
├── index.js
├── package.json
├── package-lock.json
├── README.md
├── schemas
│   ├── index.js
│   ├── v1
│   │   ├── index.js
│   │   ├── post.js
│   │   └── version.js
│   └── v2
│   ├── index.js
│   ├── post.js
│   └── version.js
└── validators
├── isPost.js
└── index.js
`

Make sure we export the relevant schemas in index.js.
`js
// schemas/v1/index.js

module.exports = {
post: require('./post')
}

// schemas/v2/index.js

module.exports = {
post: require('./post')
}
`

Draw all schemas together with their versions and export from schemas/index.js

`js
// schemas/index.js
module.exports = {
"1.0.0": require('./v1'),
"2.0.0": require('./v2')
}
`

Then create a new validator which passes the schemas to the validator along with the name of the schema. This will return your validator that takes an ssb message and options, and returns a boolean.

`js
// isPost.js
const schemas = require('./schemas')
const validate = require('ssb-schema-validation')

// Returns a function that takes an obj and opts.
module.exports = validate(schemas).with('post')
`

The result being when used...
`js
const isPost = require('./isPost')
var valid = isPost(msg, { attachErrors: true })
if (valid) {
render(msg)
} else {
render(msg.errors)
}
``