feat: export dashboard with pretty printed JSON

Resolves: #257

changelogs/fragments/257_pretty_printed_dashboard_export.yml

@@ -0,0 +1,2 @@
+minor_changes:
+- Export dashboard with pretty printed JSON so that it becomes easier to compare changes with the previous version (#257)

plugins/modules/grafana_dashboard.py

@@ -470,7 +470,7 @@ def grafana_export_dashboard(module, data):
     if dashboard_exists is True:
         try:
             with open(data['path'], 'w') as f:
-                f.write(json.dumps(dashboard))
+                f.write(json.dumps(dashboard, indent=2))
         except Exception as e:
             raise GrafanaExportException("Can't write json file : %s" % to_native(e))
         result = {'msg': "Dashboard %s exported to %s" % (uid, data['path']),

tests/integration/targets/grafana_dashboard/tasks/dashboard-export.yml

@@ -0,0 +1,33 @@
+---
+- set_fact:
+    dashboard_uid: "{{ result.uid }}"
+
+- name: Check export grafana dashboard to file
+  grafana_dashboard:
+    grafana_url: "{{ grafana_url }}"
+    grafana_user: "{{ grafana_username }}"
+    grafana_password: "{{ grafana_password }}"
+    state: export
+    path: /tmp/dashboard.json
+    overwrite: true
+    uid: "{{ dashboard_uid }}"
+  register: result
+
+- debug:
+    var: result
+
+- assert:
+    that:
+      - "result.changed == true"
+      - "result.msg == 'Dashboard {{ dashboard_uid }} exported to /tmp/dashboard.json'"
+
+- name: Load /tmp/dashboard.json or fail if missing
+  set_fact:
+    exported_dashboard_lines: "{{ lookup('file', '/tmp/dashboard.json').splitlines() }}"
+
+- name: Assert that exported dashboard contains formatted JSON
+  assert:
+    that:
+      - "exported_dashboard_lines | length >= 2"
+      - "exported_dashboard_lines[0] == '{'"
+      - "exported_dashboard_lines[-1] == '}'"

tests/integration/targets/grafana_dashboard/tasks/main.yml

@@ -3,4 +3,5 @@
   - include: delete-dashboard.yml
   - include: dashboard-from-id.yml
   - include: dashboard-from-file.yml
+  - include: dashboard-export.yml
   - include: dashboard-folder-destination.yml