DOCSP-49972 Go Choose a Connection Target

source/fundamentals/connections.txt

@@ -10,6 +10,7 @@ Connections
 .. toctree::
 
    Connection Guide </fundamentals/connections/connection-guide>
+   Choose a Connection Target </fundamentals/connections/connection-target>
    Connection Options </fundamentals/connections/connection-options>
    Network Compression </fundamentals/connections/network-compression>
    Configure TLS </fundamentals/connections/tls>
@@ -28,6 +29,7 @@ Learn how to use the {+driver-short+} to configure your application's
 connection to a MongoDB deployment in the following sections:
 
 - :ref:`golang-connection-guide`
+- :ref:`golang-connection-targets`
 - :ref:`golang-connection-options`
 - :ref:`golang-network-compression`
 - :ref:`golang-tls`

source/fundamentals/connections/connection-target.txt

@@ -0,0 +1,107 @@
+.. _golang-connection-targets:
+
+==========================
+Choose a Connection Target
+==========================
+
+.. facet::
+   :name: genre
+   :values: tutorial
+
+.. meta::
+   :description: Learn how to select connection targets for the MongoDB Go Driver.
+   :keywords: 
+
+.. contents:: On this page
+   :local:
+   :backlinks: none
+   :depth: 2
+   :class: singlecol
+
+Overview
+--------
+
+In this guide, you can learn how to use a connection string and a
+``MongoClient`` object to connect to different types of MongoDB deployments.
+
+.. tip::
+
+   To learn more about how to retrieve or format your connection string, see 
+   the :ref:`Connection URI <golang-connection-uri>` guide in 
+   the Go Connection Guide.
+
+Atlas
+-----
+
+To connect to a MongoDB deployment on Atlas, include the following elements in your
+connection string:
+
+- URL of your Atlas cluster
+- MongoDB username
+- MongoDB password
+
+Then, pass your connection string to the ``MongoClient`` constructor.
+
+When you connect to Atlas, we recommend using the {+stable-api+} client option to avoid
+breaking changes when Atlas upgrades to a new version of {+mdb-server+}.
+To learn more about the {+stable-api+} feature, see the :ref:`<stable-api>`
+guide.
+
+The following code shows how to use the {+driver-short+} to connect to an Atlas cluster. The
+code also uses the ``server_api`` field to specify a {+stable-api+} version.
+
+.. _go-connection-example-code:
+
+.. literalinclude:: /includes/fundamentals/code-snippets/srv.go
+   :language: go
+
+Local Deployments
+-----------------
+
+.. include:: /includes/localhost-connection.rst
+
+Replica Set
+-----------
+
+A MongoDB replica set deployment is a group of connected instances that
+store the same set of data. This configuration provides data
+redundancy and high data availability.
+
+To connect to a replica set deployment, specify the hostname and port numbers
+of each instance, separated by commas, and the replica set name as the value
+of the ``replicaSet`` parameter in the connection string. In the following
+example, the hostnames are ``host1``, ``host2``, and ``host3``, and the
+port numbers are all ``27017``. The replica set name is ``myRS``.
+
+.. code-block:: none
+
+   mongodb://host1:27017,host2:27017,host3:27017/?replicaSet=myRS
+
+When connecting to a replica set, the driver takes the following actions by default:
+
+- Discovers all replica set members when given the address of any one member.
+- Dispatches operations to the appropriate member, such as instructions
+  to write against the **primary**.
+
+.. tip::
+
+   You can specify just one host to connect to a replica set.
+   However, to ensure connectivity when the specified host
+   is unavailable, you should provide the full list of hosts.
+
+Direct Connection
+`````````````````
+
+To force operations on the host designated in the connection URI,
+specify the ``directConnection`` option. Direct connections exhibit the
+following behavior:
+
+- They don't support SRV strings.
+- They fail on writes when the specified host is not the **primary**.
+- They require you to specify a :manual:`secondary read preference
+  </core/read-preference/#mongodb-readmode-secondary>` when the
+  specified host isn't the **primary** node.
+
+.. note:: Replica Set in Docker
+
+   .. sharedinclude:: dbx/docker-replica-set.rst