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'use strict';
var urilib = require('url');
var attribute = require('./attribute');
var helpers = require('./helpers');
var scanSchema = require('./scan').scan;
var ValidatorResult = helpers.ValidatorResult;
var SchemaError = helpers.SchemaError;
var SchemaContext = helpers.SchemaContext;
//var anonymousBase = 'vnd.jsonschema:///';
var anonymousBase = '/';
/**
* Creates a new Validator object
* @name Validator
* @constructor
*/
var Validator = function Validator () {
// Allow a validator instance to override global custom formats or to have their
// own custom formats.
this.customFormats = Object.create(Validator.prototype.customFormats);
this.schemas = {};
this.unresolvedRefs = [];
// Use Object.create to make this extensible without Validator instances stepping on each other's toes.
this.types = Object.create(types);
this.attributes = Object.create(attribute.validators);
};
// Allow formats to be registered globally.
Validator.prototype.customFormats = {};
// Hint at the presence of a property
Validator.prototype.schemas = null;
Validator.prototype.types = null;
Validator.prototype.attributes = null;
Validator.prototype.unresolvedRefs = null;
/**
* Adds a schema with a certain urn to the Validator instance.
* @param schema
* @param urn
* @return {Object}
*/
Validator.prototype.addSchema = function addSchema (schema, base) {
var self = this;
if (!schema) {
return null;
}
var scan = scanSchema(base||anonymousBase, schema);
var ourUri = base || schema.id;
for(var uri in scan.id){
this.schemas[uri] = scan.id[uri];
}
for(var uri in scan.ref){
this.unresolvedRefs.push(uri);
}
this.unresolvedRefs = this.unresolvedRefs.filter(function(uri){
return typeof self.schemas[uri]==='undefined';
});
return this.schemas[ourUri];
};
Validator.prototype.addSubSchemaArray = function addSubSchemaArray(baseuri, schemas) {
if(!(schemas instanceof Array)) return;
for(var i=0; i<schemas.length; i++){
this.addSubSchema(baseuri, schemas[i]);
}
};
Validator.prototype.addSubSchemaObject = function addSubSchemaArray(baseuri, schemas) {
if(!schemas || typeof schemas!='object') return;
for(var p in schemas){
this.addSubSchema(baseuri, schemas[p]);
}
};
/**
* Sets all the schemas of the Validator instance.
* @param schemas
*/
Validator.prototype.setSchemas = function setSchemas (schemas) {
this.schemas = schemas;
};
/**
* Returns the schema of a certain urn
* @param urn
*/
Validator.prototype.getSchema = function getSchema (urn) {
return this.schemas[urn];
};
/**
* Validates instance against the provided schema
* @param instance
* @param schema
* @param [options]
* @param [ctx]
* @return {Array}
*/
Validator.prototype.validate = function validate (instance, schema, options, ctx) {
if (!options) {
options = {};
}
var propertyName = options.propertyName || 'instance';
// This will work so long as the function at uri.resolve() will resolve a relative URI to a relative URI
var base = urilib.resolve(options.base||anonymousBase, schema.id||'');
if(!ctx){
ctx = new SchemaContext(schema, options, propertyName, base, Object.create(this.schemas));
if (!ctx.schemas[base]) {
ctx.schemas[base] = schema;
}
var found = scanSchema(base, schema);
for(var n in found.id){
var sch = found.id[n];
ctx.schemas[n] = sch;
}
}
if (schema) {
var result = this.validateSchema(instance, schema, options, ctx);
if (!result) {
throw new Error('Result undefined');
}
return result;
}
throw new SchemaError('no schema specified', schema);
};
/**
* @param Object schema
* @return mixed schema uri or false
*/
function shouldResolve(schema) {
var ref = (typeof schema === 'string') ? schema : schema.$ref;
if (typeof ref=='string') return ref;
return false;
}
/**
* Validates an instance against the schema (the actual work horse)
* @param instance
* @param schema
* @param options
* @param ctx
* @private
* @return {ValidatorResult}
*/
Validator.prototype.validateSchema = function validateSchema (instance, schema, options, ctx) {
var result = new ValidatorResult(instance, schema, options, ctx);
// Support for the true/false schemas
if(typeof schema==='boolean') {
if(schema===true){
// `true` is always valid
schema = {};
}else if(schema===false){
// `false` is always invalid
schema = {type: []};
}
}else if(!schema){
// This might be a string
throw new Error("schema is undefined");
}
if (schema['extends']) {
if (schema['extends'] instanceof Array) {
var schemaobj = {schema: schema, ctx: ctx};
schema['extends'].forEach(this.schemaTraverser.bind(this, schemaobj));
schema = schemaobj.schema;
schemaobj.schema = null;
schemaobj.ctx = null;
schemaobj = null;
} else {
schema = helpers.deepMerge(schema, this.superResolve(schema['extends'], ctx));
}
}
// If passed a string argument, load that schema URI
var switchSchema;
if (switchSchema = shouldResolve(schema)) {
var resolved = this.resolve(schema, switchSchema, ctx);
var subctx = new SchemaContext(resolved.subschema, options, ctx.propertyPath, resolved.switchSchema, ctx.schemas);
return this.validateSchema(instance, resolved.subschema, options, subctx);
}
var skipAttributes = options && options.skipAttributes || [];
// Validate each schema attribute against the instance
for (var key in schema) {
if (!attribute.ignoreProperties[key] && skipAttributes.indexOf(key) < 0) {
var validatorErr = null;
var validator = this.attributes[key];
if (validator) {
validatorErr = validator.call(this, instance, schema, options, ctx);
} else if (options.allowUnknownAttributes === false) {
// This represents an error with the schema itself, not an invalid instance
throw new SchemaError("Unsupported attribute: " + key, schema);
}
if (validatorErr) {
result.importErrors(validatorErr);
}
}
}
if (typeof options.rewrite == 'function') {
var value = options.rewrite.call(this, instance, schema, options, ctx);
result.instance = value;
}
return result;
};
/**
* @private
* @param Object schema
* @param SchemaContext ctx
* @returns Object schema or resolved schema
*/
Validator.prototype.schemaTraverser = function schemaTraverser (schemaobj, s) {
schemaobj.schema = helpers.deepMerge(schemaobj.schema, this.superResolve(s, schemaobj.ctx));
}
/**
* @private
* @param Object schema
* @param SchemaContext ctx
* @returns Object schema or resolved schema
*/
Validator.prototype.superResolve = function superResolve (schema, ctx) {
var ref;
if(ref = shouldResolve(schema)) {
return this.resolve(schema, ref, ctx).subschema;
}
return schema;
}
/**
* @private
* @param Object schema
* @param Object switchSchema
* @param SchemaContext ctx
* @return Object resolved schemas {subschema:String, switchSchema: String}
* @throws SchemaError
*/
Validator.prototype.resolve = function resolve (schema, switchSchema, ctx) {
switchSchema = ctx.resolve(switchSchema);
// First see if the schema exists under the provided URI
if (ctx.schemas[switchSchema]) {
return {subschema: ctx.schemas[switchSchema], switchSchema: switchSchema};
}
// Else try walking the property pointer
var parsed = urilib.parse(switchSchema);
var fragment = parsed && parsed.hash;
var document = fragment && fragment.length && switchSchema.substr(0, switchSchema.length - fragment.length);
if (!document || !ctx.schemas[document]) {
throw new SchemaError("no such schema <" + switchSchema + ">", schema);
}
var subschema = helpers.objectGetPath(ctx.schemas[document], fragment.substr(1));
if(subschema===undefined){
throw new SchemaError("no such schema " + fragment + " located in <" + document + ">", schema);
}
return {subschema: subschema, switchSchema: switchSchema};
};
/**
* Tests whether the instance if of a certain type.
* @private
* @param instance
* @param schema
* @param options
* @param ctx
* @param type
* @return {boolean}
*/
Validator.prototype.testType = function validateType (instance, schema, options, ctx, type) {
if (typeof this.types[type] == 'function') {
return this.types[type].call(this, instance);
}
if (type && typeof type == 'object') {
var res = this.validateSchema(instance, type, options, ctx);
return res === undefined || !(res && res.errors.length);
}
// Undefined or properties not on the list are acceptable, same as not being defined
return true;
};
var types = Validator.prototype.types = {};
types.string = function testString (instance) {
return typeof instance == 'string';
};
types.number = function testNumber (instance) {
// isFinite returns false for NaN, Infinity, and -Infinity
return typeof instance == 'number' && isFinite(instance);
};
types.integer = function testInteger (instance) {
return (typeof instance == 'number') && instance % 1 === 0;
};
types.boolean = function testBoolean (instance) {
return typeof instance == 'boolean';
};
types.array = function testArray (instance) {
return Array.isArray(instance);
};
types['null'] = function testNull (instance) {
return instance === null;
};
types.date = function testDate (instance) {
return instance instanceof Date;
};
types.any = function testAny (instance) {
return true;
};
types.object = function testObject (instance) {
// TODO: fix this - see #15
return instance && (typeof instance) === 'object' && !(instance instanceof Array) && !(instance instanceof Date);
};
module.exports = Validator;