1 // Copyright (c) 2010 The Chromium Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4
5 #include "chrome/common/json_schema_validator.h"
6
7 #include <cfloat>
8 #include <cmath>
9
10 #include "base/string_number_conversions.h"
11 #include "base/string_util.h"
12 #include "base/values.h"
13 #include "ui/base/l10n/l10n_util.h"
14
15 namespace {
16
GetNumberValue(Value * value)17 double GetNumberValue(Value* value) {
18 double result = 0;
19 if (value->GetAsDouble(&result))
20 return result;
21
22 int int_result = 0;
23 if (value->GetAsInteger(&int_result)) {
24 return int_result;
25 }
26
27 CHECK(false) << "Unexpected value type: " << value->GetType();
28 return 0;
29 }
30
GetNumberFromDictionary(DictionaryValue * value,const std::string & key,double * number)31 bool GetNumberFromDictionary(DictionaryValue* value, const std::string& key,
32 double* number) {
33 if (value->GetDouble(key, number))
34 return true;
35
36 int int_value = 0;
37 if (value->GetInteger(key, &int_value)) {
38 *number = int_value;
39 return true;
40 }
41
42 return false;
43 }
44
45 } // namespace
46
47
Error()48 JSONSchemaValidator::Error::Error() {
49 }
50
Error(const std::string & message)51 JSONSchemaValidator::Error::Error(const std::string& message)
52 : path(message) {
53 }
54
Error(const std::string & path,const std::string & message)55 JSONSchemaValidator::Error::Error(const std::string& path,
56 const std::string& message)
57 : path(path), message(message) {
58 }
59
60
61 const char JSONSchemaValidator::kUnknownTypeReference[] =
62 "Unknown schema reference: *.";
63 const char JSONSchemaValidator::kInvalidChoice[] =
64 "Value does not match any valid type choices.";
65 const char JSONSchemaValidator::kInvalidEnum[] =
66 "Value does not match any valid enum choices.";
67 const char JSONSchemaValidator::kObjectPropertyIsRequired[] =
68 "Property is required.";
69 const char JSONSchemaValidator::kUnexpectedProperty[] =
70 "Unexpected property.";
71 const char JSONSchemaValidator::kArrayMinItems[] =
72 "Array must have at least * items.";
73 const char JSONSchemaValidator::kArrayMaxItems[] =
74 "Array must not have more than * items.";
75 const char JSONSchemaValidator::kArrayItemRequired[] =
76 "Item is required.";
77 const char JSONSchemaValidator::kStringMinLength[] =
78 "String must be at least * characters long.";
79 const char JSONSchemaValidator::kStringMaxLength[] =
80 "String must not be more than * characters long.";
81 const char JSONSchemaValidator::kStringPattern[] =
82 "String must match the pattern: *.";
83 const char JSONSchemaValidator::kNumberMinimum[] =
84 "Value must not be less than *.";
85 const char JSONSchemaValidator::kNumberMaximum[] =
86 "Value must not be greater than *.";
87 const char JSONSchemaValidator::kInvalidType[] =
88 "Expected '*' but got '*'.";
89
90
91 // static
GetJSONSchemaType(Value * value)92 std::string JSONSchemaValidator::GetJSONSchemaType(Value* value) {
93 switch (value->GetType()) {
94 case Value::TYPE_NULL:
95 return "null";
96 case Value::TYPE_BOOLEAN:
97 return "boolean";
98 case Value::TYPE_INTEGER:
99 return "integer";
100 case Value::TYPE_DOUBLE: {
101 double double_value = 0;
102 value->GetAsDouble(&double_value);
103 if (std::abs(double_value) <= std::pow(2.0, DBL_MANT_DIG) &&
104 double_value == floor(double_value)) {
105 return "integer";
106 } else {
107 return "number";
108 }
109 }
110 case Value::TYPE_STRING:
111 return "string";
112 case Value::TYPE_DICTIONARY:
113 return "object";
114 case Value::TYPE_LIST:
115 return "array";
116 default:
117 CHECK(false) << "Unexpected value type: " << value->GetType();
118 return "";
119 }
120 }
121
122 // static
FormatErrorMessage(const std::string & format,const std::string & s1)123 std::string JSONSchemaValidator::FormatErrorMessage(const std::string& format,
124 const std::string& s1) {
125 std::string ret_val = format;
126 ReplaceFirstSubstringAfterOffset(&ret_val, 0, "*", s1);
127 return ret_val;
128 }
129
130 // static
FormatErrorMessage(const std::string & format,const std::string & s1,const std::string & s2)131 std::string JSONSchemaValidator::FormatErrorMessage(const std::string& format,
132 const std::string& s1,
133 const std::string& s2) {
134 std::string ret_val = format;
135 ReplaceFirstSubstringAfterOffset(&ret_val, 0, "*", s1);
136 ReplaceFirstSubstringAfterOffset(&ret_val, 0, "*", s2);
137 return ret_val;
138 }
139
JSONSchemaValidator(DictionaryValue * schema)140 JSONSchemaValidator::JSONSchemaValidator(DictionaryValue* schema)
141 : schema_root_(schema), default_allow_additional_properties_(false) {
142 }
143
JSONSchemaValidator(DictionaryValue * schema,ListValue * types)144 JSONSchemaValidator::JSONSchemaValidator(DictionaryValue* schema,
145 ListValue* types)
146 : schema_root_(schema), default_allow_additional_properties_(false) {
147 if (!types)
148 return;
149
150 for (size_t i = 0; i < types->GetSize(); ++i) {
151 DictionaryValue* type = NULL;
152 CHECK(types->GetDictionary(i, &type));
153
154 std::string id;
155 CHECK(type->GetString("id", &id));
156
157 CHECK(types_.find(id) == types_.end());
158 types_[id] = type;
159 }
160 }
161
~JSONSchemaValidator()162 JSONSchemaValidator::~JSONSchemaValidator() {}
163
Validate(Value * instance)164 bool JSONSchemaValidator::Validate(Value* instance) {
165 errors_.clear();
166 Validate(instance, schema_root_, "");
167 return errors_.empty();
168 }
169
Validate(Value * instance,DictionaryValue * schema,const std::string & path)170 void JSONSchemaValidator::Validate(Value* instance,
171 DictionaryValue* schema,
172 const std::string& path) {
173 // If this schema defines itself as reference type, save it in this.types.
174 std::string id;
175 if (schema->GetString("id", &id)) {
176 TypeMap::iterator iter = types_.find(id);
177 if (iter == types_.end())
178 types_[id] = schema;
179 else
180 CHECK(iter->second == schema);
181 }
182
183 // If the schema has a $ref property, the instance must validate against
184 // that schema. It must be present in types_ to be referenced.
185 std::string ref;
186 if (schema->GetString("$ref", &ref)) {
187 TypeMap::iterator type = types_.find(ref);
188 if (type == types_.end()) {
189 errors_.push_back(
190 Error(path, FormatErrorMessage(kUnknownTypeReference, ref)));
191 } else {
192 Validate(instance, type->second, path);
193 }
194 return;
195 }
196
197 // If the schema has a choices property, the instance must validate against at
198 // least one of the items in that array.
199 ListValue* choices = NULL;
200 if (schema->GetList("choices", &choices)) {
201 ValidateChoices(instance, choices, path);
202 return;
203 }
204
205 // If the schema has an enum property, the instance must be one of those
206 // values.
207 ListValue* enumeration = NULL;
208 if (schema->GetList("enum", &enumeration)) {
209 ValidateEnum(instance, enumeration, path);
210 return;
211 }
212
213 std::string type;
214 schema->GetString("type", &type);
215 CHECK(!type.empty());
216 if (type != "any") {
217 if (!ValidateType(instance, type, path))
218 return;
219
220 // These casts are safe because of checks in ValidateType().
221 if (type == "object")
222 ValidateObject(static_cast<DictionaryValue*>(instance), schema, path);
223 else if (type == "array")
224 ValidateArray(static_cast<ListValue*>(instance), schema, path);
225 else if (type == "string")
226 ValidateString(static_cast<StringValue*>(instance), schema, path);
227 else if (type == "number" || type == "integer")
228 ValidateNumber(instance, schema, path);
229 else if (type != "boolean" && type != "null")
230 CHECK(false) << "Unexpected type: " << type;
231 }
232 }
233
ValidateChoices(Value * instance,ListValue * choices,const std::string & path)234 void JSONSchemaValidator::ValidateChoices(Value* instance,
235 ListValue* choices,
236 const std::string& path) {
237 size_t original_num_errors = errors_.size();
238
239 for (size_t i = 0; i < choices->GetSize(); ++i) {
240 DictionaryValue* choice = NULL;
241 CHECK(choices->GetDictionary(i, &choice));
242
243 Validate(instance, choice, path);
244 if (errors_.size() == original_num_errors)
245 return;
246
247 // We discard the error from each choice. We only want to know if any of the
248 // validations succeeded.
249 errors_.resize(original_num_errors);
250 }
251
252 // Now add a generic error that no choices matched.
253 errors_.push_back(Error(path, kInvalidChoice));
254 return;
255 }
256
ValidateEnum(Value * instance,ListValue * choices,const std::string & path)257 void JSONSchemaValidator::ValidateEnum(Value* instance,
258 ListValue* choices,
259 const std::string& path) {
260 for (size_t i = 0; i < choices->GetSize(); ++i) {
261 Value* choice = NULL;
262 CHECK(choices->Get(i, &choice));
263 switch (choice->GetType()) {
264 case Value::TYPE_NULL:
265 case Value::TYPE_BOOLEAN:
266 case Value::TYPE_STRING:
267 if (instance->Equals(choice))
268 return;
269 break;
270
271 case Value::TYPE_INTEGER:
272 case Value::TYPE_DOUBLE:
273 if (instance->IsType(Value::TYPE_INTEGER) ||
274 instance->IsType(Value::TYPE_DOUBLE)) {
275 if (GetNumberValue(choice) == GetNumberValue(instance))
276 return;
277 }
278 break;
279
280 default:
281 CHECK(false) << "Unexpected type in enum: " << choice->GetType();
282 }
283 }
284
285 errors_.push_back(Error(path, kInvalidEnum));
286 }
287
ValidateObject(DictionaryValue * instance,DictionaryValue * schema,const std::string & path)288 void JSONSchemaValidator::ValidateObject(DictionaryValue* instance,
289 DictionaryValue* schema,
290 const std::string& path) {
291 DictionaryValue* properties = NULL;
292 schema->GetDictionary("properties", &properties);
293 if (properties) {
294 for (DictionaryValue::key_iterator key = properties->begin_keys();
295 key != properties->end_keys(); ++key) {
296 std::string prop_path = path.empty() ? *key : (path + "." + *key);
297 DictionaryValue* prop_schema = NULL;
298 CHECK(properties->GetDictionary(*key, &prop_schema));
299
300 Value* prop_value = NULL;
301 if (instance->Get(*key, &prop_value)) {
302 Validate(prop_value, prop_schema, prop_path);
303 } else {
304 // Properties are required unless there is an optional field set to
305 // 'true'.
306 bool is_optional = false;
307 prop_schema->GetBoolean("optional", &is_optional);
308 if (!is_optional) {
309 errors_.push_back(Error(prop_path, kObjectPropertyIsRequired));
310 }
311 }
312 }
313 }
314
315 DictionaryValue* additional_properties_schema = NULL;
316 if (SchemaAllowsAnyAdditionalItems(schema, &additional_properties_schema))
317 return;
318
319 // Validate additional properties.
320 for (DictionaryValue::key_iterator key = instance->begin_keys();
321 key != instance->end_keys(); ++key) {
322 if (properties && properties->HasKey(*key))
323 continue;
324
325 std::string prop_path = path.empty() ? *key : path + "." + *key;
326 if (!additional_properties_schema) {
327 errors_.push_back(Error(prop_path, kUnexpectedProperty));
328 } else {
329 Value* prop_value = NULL;
330 CHECK(instance->Get(*key, &prop_value));
331 Validate(prop_value, additional_properties_schema, prop_path);
332 }
333 }
334 }
335
ValidateArray(ListValue * instance,DictionaryValue * schema,const std::string & path)336 void JSONSchemaValidator::ValidateArray(ListValue* instance,
337 DictionaryValue* schema,
338 const std::string& path) {
339 DictionaryValue* single_type = NULL;
340 size_t instance_size = instance->GetSize();
341 if (schema->GetDictionary("items", &single_type)) {
342 int min_items = 0;
343 if (schema->GetInteger("minItems", &min_items)) {
344 CHECK(min_items >= 0);
345 if (instance_size < static_cast<size_t>(min_items)) {
346 errors_.push_back(Error(path, FormatErrorMessage(
347 kArrayMinItems, base::IntToString(min_items))));
348 }
349 }
350
351 int max_items = 0;
352 if (schema->GetInteger("maxItems", &max_items)) {
353 CHECK(max_items >= 0);
354 if (instance_size > static_cast<size_t>(max_items)) {
355 errors_.push_back(Error(path, FormatErrorMessage(
356 kArrayMaxItems, base::IntToString(max_items))));
357 }
358 }
359
360 // If the items property is a single schema, each item in the array must
361 // validate against that schema.
362 for (size_t i = 0; i < instance_size; ++i) {
363 Value* item = NULL;
364 CHECK(instance->Get(i, &item));
365 std::string i_str = base::UintToString(i);
366 std::string item_path = path.empty() ? i_str : (path + "." + i_str);
367 Validate(item, single_type, item_path);
368 }
369
370 return;
371 }
372
373 // Otherwise, the list must be a tuple type, where each item in the list has a
374 // particular schema.
375 ValidateTuple(instance, schema, path);
376 }
377
ValidateTuple(ListValue * instance,DictionaryValue * schema,const std::string & path)378 void JSONSchemaValidator::ValidateTuple(ListValue* instance,
379 DictionaryValue* schema,
380 const std::string& path) {
381 ListValue* tuple_type = NULL;
382 schema->GetList("items", &tuple_type);
383 size_t tuple_size = tuple_type ? tuple_type->GetSize() : 0;
384 if (tuple_type) {
385 for (size_t i = 0; i < tuple_size; ++i) {
386 std::string i_str = base::UintToString(i);
387 std::string item_path = path.empty() ? i_str : (path + "." + i_str);
388 DictionaryValue* item_schema = NULL;
389 CHECK(tuple_type->GetDictionary(i, &item_schema));
390 Value* item_value = NULL;
391 instance->Get(i, &item_value);
392 if (item_value && item_value->GetType() != Value::TYPE_NULL) {
393 Validate(item_value, item_schema, item_path);
394 } else {
395 bool is_optional = false;
396 item_schema->GetBoolean("optional", &is_optional);
397 if (!is_optional) {
398 errors_.push_back(Error(item_path, kArrayItemRequired));
399 return;
400 }
401 }
402 }
403 }
404
405 DictionaryValue* additional_properties_schema = NULL;
406 if (SchemaAllowsAnyAdditionalItems(schema, &additional_properties_schema))
407 return;
408
409 size_t instance_size = instance->GetSize();
410 if (additional_properties_schema) {
411 // Any additional properties must validate against the additionalProperties
412 // schema.
413 for (size_t i = tuple_size; i < instance_size; ++i) {
414 std::string i_str = base::UintToString(i);
415 std::string item_path = path.empty() ? i_str : (path + "." + i_str);
416 Value* item_value = NULL;
417 CHECK(instance->Get(i, &item_value));
418 Validate(item_value, additional_properties_schema, item_path);
419 }
420 } else if (instance_size > tuple_size) {
421 errors_.push_back(Error(path, FormatErrorMessage(
422 kArrayMaxItems, base::UintToString(tuple_size))));
423 }
424 }
425
ValidateString(StringValue * instance,DictionaryValue * schema,const std::string & path)426 void JSONSchemaValidator::ValidateString(StringValue* instance,
427 DictionaryValue* schema,
428 const std::string& path) {
429 std::string value;
430 CHECK(instance->GetAsString(&value));
431
432 int min_length = 0;
433 if (schema->GetInteger("minLength", &min_length)) {
434 CHECK(min_length >= 0);
435 if (value.size() < static_cast<size_t>(min_length)) {
436 errors_.push_back(Error(path, FormatErrorMessage(
437 kStringMinLength, base::IntToString(min_length))));
438 }
439 }
440
441 int max_length = 0;
442 if (schema->GetInteger("maxLength", &max_length)) {
443 CHECK(max_length >= 0);
444 if (value.size() > static_cast<size_t>(max_length)) {
445 errors_.push_back(Error(path, FormatErrorMessage(
446 kStringMaxLength, base::IntToString(max_length))));
447 }
448 }
449
450 CHECK(!schema->HasKey("pattern")) << "Pattern is not supported.";
451 }
452
ValidateNumber(Value * instance,DictionaryValue * schema,const std::string & path)453 void JSONSchemaValidator::ValidateNumber(Value* instance,
454 DictionaryValue* schema,
455 const std::string& path) {
456 double value = GetNumberValue(instance);
457
458 // TODO(aa): It would be good to test that the double is not infinity or nan,
459 // but isnan and isinf aren't defined on Windows.
460
461 double minimum = 0;
462 if (GetNumberFromDictionary(schema, "minimum", &minimum)) {
463 if (value < minimum)
464 errors_.push_back(Error(path, FormatErrorMessage(
465 kNumberMinimum, base::DoubleToString(minimum))));
466 }
467
468 double maximum = 0;
469 if (GetNumberFromDictionary(schema, "maximum", &maximum)) {
470 if (value > maximum)
471 errors_.push_back(Error(path, FormatErrorMessage(
472 kNumberMaximum, base::DoubleToString(maximum))));
473 }
474 }
475
ValidateType(Value * instance,const std::string & expected_type,const std::string & path)476 bool JSONSchemaValidator::ValidateType(Value* instance,
477 const std::string& expected_type,
478 const std::string& path) {
479 std::string actual_type = GetJSONSchemaType(instance);
480 if (expected_type == actual_type ||
481 (expected_type == "number" && actual_type == "integer")) {
482 return true;
483 } else {
484 errors_.push_back(Error(path, FormatErrorMessage(
485 kInvalidType, expected_type, actual_type)));
486 return false;
487 }
488 }
489
SchemaAllowsAnyAdditionalItems(DictionaryValue * schema,DictionaryValue ** additional_properties_schema)490 bool JSONSchemaValidator::SchemaAllowsAnyAdditionalItems(
491 DictionaryValue* schema, DictionaryValue** additional_properties_schema) {
492 // If the validator allows additional properties globally, and this schema
493 // doesn't override, then we can exit early.
494 schema->GetDictionary("additionalProperties", additional_properties_schema);
495
496 if (*additional_properties_schema) {
497 std::string additional_properties_type("any");
498 CHECK((*additional_properties_schema)->GetString(
499 "type", &additional_properties_type));
500 return additional_properties_type == "any";
501 } else {
502 return default_allow_additional_properties_;
503 }
504 }
505