doc: Import support documentation and considerations (#1305)

Co-authored-by: lmkerbey-mdb <[email protected]>

Author: oarbusi

README.md

@@ -14,15 +14,16 @@ See the [`cfn` examples](examples/README.md) to setup prerequisites and get star
 See the [cdk examples](https://github.com/mongodb/awscdk-resources-mongodbatlas/blob/main/examples/README.md) to setup prerequisites and get started with your first cluster using our AWS CDK sample code.
 
 ## Limitations
-1. [Resource import](https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/resource-import.html) is not supported for third-party resources.
-
-2. Any third-party resource must support all CRUD operations. MongoDB Atlas for CloudFormation does not support the following MongoDB Atlas resources because they do not support all CRUD operations: 
+1. Any third-party resource must support all CRUD operations. MongoDB Atlas for CloudFormation does not support the following MongoDB Atlas resources because they do not support all CRUD operations: 
 
 * cloud-backup-snapshot-export-job
 * cloud-provider-access
 * federated-settings-identity-provider
 * federated-settings-org-configs
 
+## Import Support
+CloudFormation import is supported for MongoDB Atlas resources. This allows you to bring existing resources under CloudFormation management. For more details, please see [Resource Import Operations](https://github.com/mongodb/mongodbatlas-cloudformation-resources/blob/master/cfn-resources/README.md#resource-import-operations) section.
+
 ## Support, Bugs, Feature Requests
 Feature requests can be submitted at [feedback.mongodb.com](https://feedback.mongodb.com/forums/924145-atlas/category/392596-atlas-cloudformation-resources) - just select "Atlas CloudFormation Resources" as the category or vote for an already suggested feature.
 

cfn-resources/README.md

@@ -60,6 +60,20 @@ Note these are also hosted on AWS CloudFormation Public Registry under Third Par
 | 47  | stream-connection                                        | ![Build](https://img.shields.io/badge/GA-green) | [example](../examples/atlas-streams/stream-connection/stream-connection.json)                                                                                      | [./stream-connection/test](./stream-connection/test)  
 |47  | resource-policy                                        | ![Build](https://img.shields.io/badge/Beta-yellow) | [example](../examples/resource-policy/resource-policy.json)                                                                                      | [./resource-policy/test](./resource-policy/test)  
 
+## Resource Import Operations
+
+All MongoDB Atlas AWS CloudFormation resources support the import operation, allowing you to bring existing Atlas resources under CloudFormation management. When importing resources, please consider the following:
+
+### Import Requirements and Considerations
+
+1. **DeletionPolicy Attribute**: Your resource template must include the [DeletionPolicy](https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/aws-attribute-deletionpolicy.html) attribute in order to specify what happens to the resource when it is removed from the stack.
+
+2. **UPDATE Operation Required**: The import operation executes the UPDATE operation behind the scenes. Therefore, UPDATE functionality must be properly implemented for the resource type to support import. For more datails on when the update is run, please see [Create a stack from existing resources using the AWS Management Console](https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/resource-import-new-stack.html#resource-import-new-stack-console) or [Import an existing resource into a stack using the AWS Management Console](https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/resource-import-existing-stack.html#resource-import-existing-stack-console) or 
+
+3. **Outputs Restrictions**: You cannot modify or add [Outputs](https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/outputs-section-structure.html) to the template during the import operation. However, you can add outputs after the import is complete.
+
+For more details, refer to the [official AWS Resource Import documentation](https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/resource-import.html).
+
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cfn-resources/private-endpoint/upgradeguidev2/V2-UpgradeGuide.md

@@ -15,12 +15,7 @@ leverage the new split private endpoint version, all without the necessity of de
 MongoDB Atlas or AWS private endpoints
 
 ## Cloud Formation Limitations
-before we start with the upgrade progress we need to understand the next limitations:
-
-- For the migration we will be using the IMPORT feature provided by CloudFormation, the import process is not fully supported for third party resources, and it has the next limitations:
-  
-  - the import does not support UPDATE DELETE or CREATE resources, it can only READ existing resources
-  - the import process does not support changes or additions on any Output, so all the outputs that we want to modify or any reference to the imported resources, must be removed or hardcoded before the import, and later updated 
+For the migration we will be using the IMPORT feature provided by CloudFormation. Before we start with the upgrade progress we need to understand the [Import Requirements and Considerations](https://github.com/mongodb/mongodbatlas-cloudformation-resources/blob/master/cfn-resources/README.md#resource-import-operations)
 
 ## Update process:
 In this example, we will walk through a recommended update procedure. We'll start with an existing stack that includes a project and a private endpoint (V1), and then proceed to upgrade it to utilize the new Splited private endpoint V2, all without needing to make any changes to your existing MongoDB Atlas resources