DRIVERS-2449 Omit mongocryptd client (#1330)

Author: DmitryLukyanov

source/client-side-encryption/client-side-encryption.rst

@@ -4,6 +4,8 @@ Client Side Encryption
 
 :Status: Accepted
 :Minimum Server Version: 4.2 (CSFLE), 6.0 (Queryable Encryption)
+:Last Modified: 2022-10-26
+:Version: 1.11.0
 
 .. _lmc-c-api: https://github.com/mongodb/libmongocrypt/blob/master/src/mongocrypt.h.in
 
@@ -1572,6 +1574,9 @@ is propagated to the user.
 Connecting to mongocryptd_
 --------------------------
 
+If the crypt_shared_ library is loaded, the driver MUST NOT attempt to connect
+to mongocryptd_. (Refer: `Detecting crypt_shared Availability`_).
+
 Single-threaded drivers MUST connect with `serverSelectionTryOnce=false <../server-selection/server-selection.rst#serverselectiontryonce>`_
 , connectTimeoutMS=10000, and MUST bypass `cooldownMS <../server-discovery-and-monitoring/server-discovery-and-monitoring.rst#cooldownms>`__ when connecting to mongocryptd. See `Why are serverSelectionTryOnce and cooldownMS disabled for single-threaded drivers connecting to mongocryptd?`_.
 
@@ -1583,7 +1588,7 @@ selection error is propagated to the user.
 .. note::
 
    A correctly-behaving driver will never attempt to connect to mongocryptd_
-   when |opt-crypt_shared-required| is set to |true|.
+   when |opt-crypt_shared-required| is set to |true| or crypt_shared_ is loaded.
 
 ClientEncryption
 ================
@@ -2515,6 +2520,7 @@ Changelog
    :align: left
 
    Date, Description
+   22-10-26, Do not connect to `mongocryptd` if shared library is loaded.
    22-10-11, Specify a timeout on Azure IMDS HTTP requests and fix the resource URL
    22-10-05, Remove spec front matter and ``versionadded`` RST macros (since spec version was removed)
    22-09-26, Add behavior for automatic Azure KeyVault credentials for ``kmsProviders``.

source/client-side-encryption/tests/README.rst

@@ -2379,3 +2379,43 @@ This should successfully load and use the Azure credentials of the service accou
 attached to the virtual machine.
 
 Expect the key to be successfully created.
+
+20. Bypass creating mongocryptd client when shared library is loaded
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+.. note::
+
+   IMPORTANT: If crypt_shared_ is not visible to the operating system's library
+   search mechanism, this test should be skipped.
+
+
+The following tests that a mongocryptd client is not created when shared library is in-use.
+
+#. Start a new thread (referred to as ``listenerThread``)
+
+#. On ``listenerThread``, create a TcpListener on 127.0.0.1 endpoint and port 27021. Start the listener and wait for establishing connections.
+   If any connection is established, then signal about this to the main thread.
+   
+   Drivers MAY pass a different port if they expect their testing infrastructure to be using port 27021. Pass a port that should be free.
+
+#. Create a MongoClient configured with auto encryption (referred to as ``client_encrypted``)
+
+   Configure the required options. Use the ``local`` KMS provider as follows:
+
+   .. code:: javascript
+
+      { "local": { "key": <base64 decoding of LOCAL_MASTERKEY> } }
+
+   Configure with the ``keyVaultNamespace`` set to ``keyvault.datakeys``.
+
+   Configure the following ``extraOptions``:
+
+   .. code:: javascript
+
+      {
+        "mongocryptdURI": "mongodb://localhost:27021"
+      }
+   
+#. Use ``client_encrypted`` to insert the document ``{"unencrypted": "test"}`` into ``db.coll``. 
+
+#. Expect no signal from ``listenerThread``.