Onboard Load Balancer (part 4: acc tests, examples and documentation) (#117)

* Implement acceptance test

* Add resource and data source to the provider

* Add examples and markdown description

* Generate docs

* Adjustments after review

* Move load balancer supporting infrastructure from resource config to example

docs/data-sources/loadbalancer.md

@@ -0,0 +1,97 @@
+---
+# generated by https://github.com/hashicorp/terraform-plugin-docs
+page_title: "stackit_loadbalancer Data Source - stackit"
+subcategory: ""
+description: |-
+  Load Balancer resource schema.
+---
+
+# stackit_loadbalancer (Data Source)
+
+Load Balancer resource schema.
+
+## Example Usage
+
+```terraform
+data "stackit_loadbalancer" "example" {
+  project_id = "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx"
+  name       = "example-load-balancer"
+}
+```
+
+<!-- schema generated by tfplugindocs -->
+## Schema
+
+### Required
+
+- `name` (String) Load balancer name.
+- `project_id` (String) STACKIT project ID to which the Load Balancer is associated.
+
+### Read-Only
+
+- `external_address` (String) External Load Balancer IP address where this Load Balancer is exposed.
+- `id` (String) Terraform's internal resource ID. It is structured as "`project_id`","`name`".
+- `listeners` (Attributes List) List of all listeners which will accept traffic. Limited to 20. (see [below for nested schema](#nestedatt--listeners))
+- `networks` (Attributes List) List of networks that listeners and targets reside in. (see [below for nested schema](#nestedatt--networks))
+- `options` (Attributes) Defines any optional functionality you want to have enabled on your load balancer. (see [below for nested schema](#nestedatt--options))
+- `private_address` (String) Transient private Load Balancer IP address. It can change any time.
+- `target_pools` (Attributes List) List of all target pools which will be used in the Load Balancer. Limited to 20. (see [below for nested schema](#nestedatt--target_pools))
+
+<a id="nestedatt--listeners"></a>
+### Nested Schema for `listeners`
+
+Read-Only:
+
+- `display_name` (String)
+- `port` (Number) Port number where we listen for traffic.
+- `protocol` (String) Protocol is the highest network protocol we understand to load balance.
+- `target_pool` (String) Reference target pool by target pool name.
+
+
+<a id="nestedatt--networks"></a>
+### Nested Schema for `networks`
+
+Read-Only:
+
+- `network_id` (String) Openstack network ID.
+- `role` (String) The role defines how the load balancer is using the network.
+
+
+<a id="nestedatt--options"></a>
+### Nested Schema for `options`
+
+Read-Only:
+
+- `acl` (Set of String) Load Balancer is accessible only from an IP address in this range.
+- `private_network_only` (Boolean) If true, Load Balancer is accessible only via a private network IP address.
+
+
+<a id="nestedatt--target_pools"></a>
+### Nested Schema for `target_pools`
+
+Read-Only:
+
+- `active_health_check` (Attributes) (see [below for nested schema](#nestedatt--target_pools--active_health_check))
+- `name` (String) Target pool name.
+- `target_port` (Number) Identical port number where each target listens for traffic.
+- `targets` (Attributes List) List of all targets which will be used in the pool. Limited to 250. (see [below for nested schema](#nestedatt--target_pools--targets))
+
+<a id="nestedatt--target_pools--active_health_check"></a>
+### Nested Schema for `target_pools.active_health_check`
+
+Read-Only:
+
+- `healthy_threshold` (Number) Healthy threshold of the health checking.
+- `interval` (String) Interval duration of health checking in seconds.
+- `interval_jitter` (String) Interval duration threshold of the health checking in seconds.
+- `timeout` (String) Active health checking timeout duration in seconds.
+- `unhealthy_threshold` (Number) Unhealthy threshold of the health checking.
+
+
+<a id="nestedatt--target_pools--targets"></a>
+### Nested Schema for `target_pools.targets`
+
+Read-Only:
+
+- `display_name` (String) Target display name
+- `ip` (String) Target IP