Deny importing read-only datasource (#1717)

Closes #1682

Author: julienduchesne

internal/resources/grafana/resource_data_source.go

@@ -36,7 +36,20 @@ source selected (via the 'type' argument).
 		SchemaVersion: 1,
 
 		Importer: &schema.ResourceImporter{
-			StateContext: schema.ImportStatePassthroughContext,
+			StateContext: func(ctx context.Context, d *schema.ResourceData, meta interface{}) ([]*schema.ResourceData, error) {
+				client, _, idStr := OAPIClientFromExistingOrgResource(meta, d.Id())
+
+				resp, err := client.Datasources.GetDataSourceByUID(idStr)
+				if err != nil {
+					return nil, err
+				}
+
+				if resp.Payload.ReadOnly {
+					return nil, fmt.Errorf("this Grafana data source is read-only. It cannot be imported as a resource. Use the `data_grafana_data_source` data source instead")
+				}
+
+				return schema.ImportStatePassthroughContext(ctx, d, meta)
+			},
 		},
 
 		Schema: map[string]*schema.Schema{

internal/resources/grafana/resource_data_source_test.go

@@ -426,6 +426,24 @@ func TestAccDataSource_SeparateConfig(t *testing.T) {
 	})
 }
 
+func TestAccDataSource_ImportReadOnly(t *testing.T) {
+	testutils.CheckCloudInstanceTestsEnabled(t)
+
+	resource.ParallelTest(t, resource.TestCase{
+		ProtoV5ProviderFactories: testutils.ProtoV5ProviderFactories,
+		Steps: []resource.TestStep{
+			{
+				Config:            `resource "grafana_data_source" "prometheus" {}`,
+				ImportState:       true,
+				ResourceName:      "grafana_data_source.prometheus",
+				ImportStateVerify: true,
+				ImportStateId:     "grafanacloud-prom",
+				ExpectError:       regexp.MustCompile("this Grafana data source is read-only. It cannot be imported as a resource. Use the `data_grafana_data_source` data source instead"),
+			},
+		},
+	})
+}
+
 func testAccDatasourceInOrganization(orgName string) string {
 	return fmt.Sprintf(`
 resource "grafana_organization" "test" {