Specify JSON Schema Validation指定JSON架构验证

Connect to your MongoDB deployment.连接到MongoDB部署。

To connect to a local MongoDB instance or MongoDB Atlas deployment using mongosh, refer to the steps in Connect to a Deployment or Connect via mongosh.要使用mongosh连接到本地MongoDB实例或MongoDB Atlas部署，请参阅连接到部署或通过mongosh进行连接中的步骤。

Create a collection with validation.创建具有验证功能的集合。

In mongosh, run the following command to create a students collection and use the $jsonSchema operator to set schema validation rules:在mongosh中，运行以下命令创建学生集合，并使用$jsonSchema运算符设置模式验证规则：

db.createCollection("students", {
   validator: {
      $jsonSchema: {
         bsonType: "object",
         title: "Student Object Validation",
         required: [ "address", "major", "name", "year" ],
         properties: {
            name: {
               bsonType: "string",
               description: "'name' must be a string and is required"
            },
            year: {
               bsonType: "int",
               minimum: 2017,
               maximum: 3017,
               description: "'year' must be an integer in [ 2017, 3017 ] and is required"
            },
            gpa: {
               bsonType: [ "double" ],
               description: "'gpa' must be a double if the field exists"
            }
         }
      }
   }
} )

Confirm that the validation prevents invalid documents.确认验证可防止无效文档。

Run the following command. The insert operation fails because gpa is an integer when the validator requires a double.运行以下命令。插入操作失败，因为当validator需要double时，gpa是一个整数。

db.students.insertOne( {
   name: "Alice",
   year: Int32( 2019 ),
   major: "History",
   gpa: Int32(3),
   address: {
      city: "NYC",
      street: "33rd Street"
   }
} )

MongoServerError: Document failed validation

Additional information: {
  failingDocumentId: ObjectId("630d093a931191850b40d0a9"),
  details: {
    operatorName: '$jsonSchema',
    title: 'Student Object Validation',
    schemaRulesNotSatisfied: [
      {
        operatorName: 'properties',
        propertiesNotSatisfied: [
          {
            propertyName: 'gpa',
            description: "'gpa' must be a double if the field exists",
            details: [
              {
                operatorName: 'bsonType',
                specifiedAs: { bsonType: [ 'double' ] },
                reason: 'type did not match',
                consideredValue: 3,
                consideredType: 'int'
              }
            ]
          }
        ]
      }
    ]
  }
}

config.set("inspectDepth", Infinity)

Insert a valid document.插入有效文档。

If you change the gpa field value to a double type, the insert operation succeeds. Run the following command to insert the valid document:如果将gpa字段值更改为double类型，则插入操作成功。运行以下命令以插入有效文档：

db.students.insertOne( {
   name: "Alice",
   year: Int32(2019),
   major: "History",
   gpa: Double(3.0),
   address: {
      city: "NYC",
      street: "33rd Street"
   }
} )

Query for the valid document.查询有效文档。

To confirm that you've successfully inserted the document, run the following command to query the students collection:要确认您已成功插入文档，请运行以下命令查询students集合：

db.students.find()

[
   {
      _id: ObjectId("62bb413014b92d148400f7a5"),
      name: 'Alice',
      year: 2019,
      major: 'History',
      gpa: 3,
      address: { city: 'NYC', street: '33rd Street' }
   }
]