docs: document provider Kubernetes configuration block (argoproj-labs#102)

Author: oboukili

docs/index.md

@@ -27,3 +27,23 @@ provider "argocd" {
 * `port_forward_with_namespace` - (Optional)
 * `headers` - (Optional) Additional headers to add to each request to the ArgoCD server.
 * `insecure` - (Optional) Whether to skip TLS server certificate. Can be set through the `ARGOCD_INSECURE` environment variable.
+* `kubernetes` - Kubernetes configuration block.
+
+The `kubernetes` block supports:
+
+* `config_path` - (Optional) Path to the kube config file. Can be sourced from `KUBE_CONFIG_PATH`.
+* `config_paths` - (Optional) A list of paths to the kube config files. Can be sourced from `KUBE_CONFIG_PATHS`.
+* `host` - (Optional) The hostname (in form of URI) of the Kubernetes API. Can be sourced from `KUBE_HOST`.
+* `username` - (Optional) The username to use for HTTP basic authentication when accessing the Kubernetes API. Can be sourced from `KUBE_USER`.
+* `password` - (Optional) The password to use for HTTP basic authentication when accessing the Kubernetes API. Can be sourced from `KUBE_PASSWORD`.
+* `token` - (Optional) The bearer token to use for authentication when accessing the Kubernetes API. Can be sourced from `KUBE_TOKEN`.
+* `insecure` - (Optional) Whether server should be accessed without verifying the TLS certificate. Can be sourced from `KUBE_INSECURE`.
+* `client_certificate` - (Optional) PEM-encoded client certificate for TLS authentication. Can be sourced from `KUBE_CLIENT_CERT_DATA`.
+* `client_key` - (Optional) PEM-encoded client certificate key for TLS authentication. Can be sourced from `KUBE_CLIENT_KEY_DATA`.
+* `cluster_ca_certificate` - (Optional) PEM-encoded root certificates bundle for TLS authentication. Can be sourced from `KUBE_CLUSTER_CA_CERT_DATA`.
+* `config_context` - (Optional) Context to choose from the config file. Can be sourced from `KUBE_CTX`.
+* `exec` - (Optional) Configuration block to use an [exec-based credential plugin](https://kubernetes.io/docs/reference/access-authn-authz/authentication/#client-go-credential-plugins), e.g. call an external command to receive user credentials.
+    * `api_version` - (Required) API version to use when decoding the ExecCredentials resource, e.g. `client.authentication.k8s.io/v1beta1`.
+    * `command` - (Required) Command to execute.
+    * `args` - (Optional) List of arguments to pass when executing the plugin.
+    * `env` - (Optional) Map of environment variables to set when executing the plugin.