getClientEncryption()

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New in version 4.2.版本4.2中的新功能。

getClientEncryption()

Returns the ClientEncryption object for the current database collection. The ClientEncryption object supports explicit (manual) encryption and decryption of field values for Client-Side field level encryption.

getClientEncryption() has the following syntax:语法如下所示：

db.getMongo().getClientEncryption();
returns:The ClientEncryption object for current database connection.

Use the ClientEncryption object to access the following explicit encryption methods:

Behavior行为

Enable Client-Side Field Level Encryption on Database Connection

The mongo client-side field level encryption methods require a database connection with client-side field level encryption enabled. If the current database connection was not initiated with client-side field level encryption enabled, either:

  • Use the Mongo() constructor from the mongo shell to establish a connection with the required client-side field level encryption options. The Mongo() method supports both Amazon Web Services and Local Key Management Service (KMS) providers for Customer Master Key (CMK) management.

    or

  • Use the mongo shell command line options to establish a connection with the required options. The command line options only support the AWS KMS provider for CMK management.

Example示例

The getKeyVault() method automatically creates a unique index on the keyAltNames field with a partial index filter for only documents where keyAltNames exists. getKeyVault() creates this index in the key vault collection. This prevents any two data encryption keys in the same key vault from having the same key alternative name and therefore avoids ambiguity around which data encryption key is appropriate for encryption/decryption.

Warning

Do not drop the unique index created by getKeyVault(). Client-side field level encryption operations depend on server-enforced uniqueness of keyAltNames. Removing the index may lead to unexpected or unpredictable behavior.

The following example uses a locally managed KMS for the client-side field level encryption configuration.

Configuring client-side field level encryption for a locally managed key requires specifying a base64-encoded 96-byte string with no line breaks. The following operation generates a key that meets the stated requirements and loads it into the mongo shell:

TEST_LOCAL_KEY=$(echo "$(head -c 96 /dev/urandom | base64 | tr -d '\n')")
mongo --nodb --shell --eval "var TEST_LOCAL_KEY='$TEST_LOCAL_KEY'"

Create the client-side field level encryption object using the generated local key string:

var ClientSideFieldLevelEncryptionOptions = {
  "keyVaultNamespace" : "encryption.__dataKeys",
  "kmsProviders" : {
    "local" : {
"key" : BinData(0, TEST_LOCAL_KEY)    }
  }
}

Use the Mongo() constructor to create a database connection with the client-side field level encryption options. Replace the mongodb://myMongo.example.net URI with the connection string URI of the target cluster.

encryptedClient = Mongo(
"mongodb://myMongo.example.net:27017/?replSetName=myMongo",  ClientSideFieldLevelEncryptionOptions
)

Use the getClientEncryption() method to retrieve the client encryption object:

clientEncryption = encryptedClient.getClientEncryption()

For complete documentation on initiating MongoDB connections with client-side field level encryption enabled, see Mongo().