Add sqlserverflex instance (#381)

* Draft implementation sqlserverflex instance

* Finish implementation

* Fix acc test

* Changes after review

docs/data-sources/sqlserverflex_instance.md

@@ -0,0 +1,61 @@
+---
+# generated by https://github.com/hashicorp/terraform-plugin-docs
+page_title: "stackit_sqlserverflex_instance Data Source - stackit"
+subcategory: ""
+description: |-
+  MongoDB Flex instance data source schema. Must have a region specified in the provider configuration.
+---
+
+# stackit_sqlserverflex_instance (Data Source)
+
+MongoDB Flex instance data source schema. Must have a `region` specified in the provider configuration.
+
+
+
+<!-- schema generated by tfplugindocs -->
+## Schema
+
+### Required
+
+- `instance_id` (String) ID of the MongoDB Flex instance.
+- `project_id` (String) STACKIT project ID to which the instance is associated.
+
+### Read-Only
+
+- `acl` (List of String) The Access Control List (ACL) for the MongoDB Flex instance.
+- `backup_schedule` (String) The backup schedule. Should follow the cron scheduling system format (e.g. "0 0 * * *").
+- `flavor` (Attributes) (see [below for nested schema](#nestedatt--flavor))
+- `id` (String) Terraform's internal data source. ID. It is structured as "`project_id`,`instance_id`".
+- `name` (String) Instance name.
+- `options` (Attributes) Custom parameters for the MongoDB Flex instance. (see [below for nested schema](#nestedatt--options))
+- `replicas` (Number)
+- `storage` (Attributes) (see [below for nested schema](#nestedatt--storage))
+- `version` (String)
+
+<a id="nestedatt--flavor"></a>
+### Nested Schema for `flavor`
+
+Read-Only:
+
+- `cpu` (Number)
+- `description` (String)
+- `id` (String)
+- `ram` (Number)
+
+
+<a id="nestedatt--options"></a>
+### Nested Schema for `options`
+
+Read-Only:
+
+- `edition` (String)
+- `retention_days` (Number)
+
+
+<a id="nestedatt--storage"></a>
+### Nested Schema for `storage`
+
+Read-Only:
+
+- `class` (String)
+- `size` (Number)

docs/index.md

@@ -165,4 +165,5 @@ Note: AWS specific checks must be skipped as they do not work on STACKIT. For de
 - `service_account_key_path` (String) Path for the service account key used for authentication. If set, the key flow will be used to authenticate all operations.
 - `service_account_token` (String) Token used for authentication. If set, the token flow will be used to authenticate all operations.
 - `ske_custom_endpoint` (String) Custom endpoint for the Kubernetes Engine (SKE) service
+- `sqlserverflex_custom_endpoint` (String) Custom endpoint for the SQL Server Flex service
 - `token_custom_endpoint` (String) Custom endpoint for the token API, which is used to request access tokens when using the key flow

docs/resources/ske_cluster.md

@@ -81,7 +81,7 @@ Optional:
 - `max_surge` (Number) Maximum number of additional VMs that are created during an update.
 - `max_unavailable` (Number) Maximum number of VMs that that can be unavailable during an update.
 - `os_name` (String) The name of the OS image. Defaults to `flatcar`.
-- `os_version` (String, Deprecated) This field is deprecated, use `os_version_min` to configure the version and `os_version_used` to get the currently used version instead
+- `os_version` (String, Deprecated) This field is deprecated, use `os_version_min` to configure the version and `os_version_used` to get the currently used version instead.
 - `os_version_min` (String) The minimum OS image version. This field will be used to set the minimum OS image version on creation/update of the cluster. If unset, the latest supported OS image version will be used. SKE automatically updates the cluster Kubernetes version if you have set `maintenance.enable_kubernetes_version_updates` to true or if there is a mandatory update, as described in [Updates for Kubernetes versions and Operating System versions in SKE](https://docs.stackit.cloud/stackit/en/version-updates-in-ske-10125631.html). To get the current OS image version being used for the node pool, use the read-only `os_version_used` field.
 - `taints` (Attributes List) Specifies a taint list as defined below. (see [below for nested schema](#nestedatt--node_pools--taints))
 - `volume_size` (Number) The volume size in GB. Defaults to `20`

docs/resources/sqlserverflex_instance.md

@@ -0,0 +1,67 @@
+---
+# generated by https://github.com/hashicorp/terraform-plugin-docs
+page_title: "stackit_sqlserverflex_instance Resource - stackit"
+subcategory: ""
+description: |-
+  SQL Server Flex instance resource schema. Must have a region specified in the provider configuration.
+---
+
+# stackit_sqlserverflex_instance (Resource)
+
+SQL Server Flex instance resource schema. Must have a `region` specified in the provider configuration.
+
+
+
+<!-- schema generated by tfplugindocs -->
+## Schema
+
+### Required
+
+- `flavor` (Attributes) (see [below for nested schema](#nestedatt--flavor))
+- `name` (String) Instance name.
+- `project_id` (String) STACKIT project ID to which the instance is associated.
+
+### Optional
+
+- `acl` (List of String) The Access Control List (ACL) for the SQL Server Flex instance.
+- `backup_schedule` (String) The backup schedule. Should follow the cron scheduling system format (e.g. "0 0 * * *")
+- `options` (Attributes) (see [below for nested schema](#nestedatt--options))
+- `storage` (Attributes) (see [below for nested schema](#nestedatt--storage))
+- `version` (String)
+
+### Read-Only
+
+- `id` (String) Terraform's internal resource ID. It is structured as "`project_id`,`instance_id`".
+- `instance_id` (String) ID of the SQL Server Flex instance.
+- `replicas` (Number)
+
+<a id="nestedatt--flavor"></a>
+### Nested Schema for `flavor`
+
+Required:
+
+- `cpu` (Number)
+- `ram` (Number)
+
+Read-Only:
+
+- `description` (String)
+- `id` (String)
+
+
+<a id="nestedatt--options"></a>
+### Nested Schema for `options`
+
+Optional:
+
+- `edition` (String)
+- `retention_days` (Number)
+
+
+<a id="nestedatt--storage"></a>
+### Nested Schema for `storage`
+
+Optional:
+
+- `class` (String)
+- `size` (Number)