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// Copyright 2020 CUE Authors
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
// Package jsonschema implements the JSON schema standard.
//
// Mapping and Linking
//
// JSON Schema are often defined in a single file. CUE, on the other hand
// idomatically defines schema as a definition.
//
// CUE:
// $schema: which schema is used for validation.
// $id: which validation does this schema provide.
//
// Foo: _ @jsonschema(sc)
// @source(https://...) // What schema is used to validate.
//
// NOTE: JSON Schema is a draft standard and may undergo backwards incompatible
// changes.
package jsonschema
import (
"cuelang.org/go/cue"
"cuelang.org/go/cue/ast"
"cuelang.org/go/cue/token"
)
// Extract converts JSON Schema data into an equivalent CUE representation.
//
// The generated CUE schema is guaranteed to deem valid any value that is
// a valid instance of the source JSON schema.
func Extract(data *cue.Instance, cfg *Config) (f *ast.File, err error) {
d := &decoder{
cfg: cfg,
imports: map[string]*ast.Ident{},
}
f = d.decode(data.Value())
if d.errs != nil {
return nil, d.errs
}
return f, nil
}
// A Config configures a JSON Schema encoding or decoding.
type Config struct {
PkgName string
// ID sets the URL of the original source, corresponding to the $id field.
ID string
// JSON reference of location containing schema. The empty string indicates
// that there is a single schema at the root.
//
// Examples:
// "#/" top-level fields are schemas.
// "#/components/schemas" the canonical OpenAPI location.
Root string
// Map maps the locations of schemas and definitions to a new location.
// References are updated accordingly.
//
// The default mapping is
// {} {"Schema"}
// {"definitions", foo} {"Defs", strings.Title(foo)}
// {"$defs", foo} {"Defs", strings.Title(foo)}
Map func(pos token.Pos, path []string) ([]string, error)
// TODO: configurability to make it compatible with OpenAPI, such as
// - locations of definitions: #/components/schemas, for instance.
// - selection and definition of formats
// - documentation hooks.
// Strict reports an error for unsupported features, rather than ignoring
// them.
Strict bool
_ struct{} // prohibit casting from different type.
}