[json] Add endpoint to delete a setting (reset to defaults)

README_JSON_API.md

@@ -2173,8 +2173,9 @@ curl -X GET "http://localhost:3689/api/config"
 | --------- | ------------------------------------------------ | ------------------------------------ |
 | GET       | [/api/settings](#list-categories)                | Get all available categories         |
 | GET       | [/api/settings/{category-name}](#get-a-category) | Get all available options for a category   |
-| GET       | [/api/settings/{category-name}/{option-name}](#get-a-option) | Get a single setting option    |
-| PUT       | [/api/settings/{category-name}/{option-name}](#change-a-option-value) | Change the value of a setting option    |
+| GET       | [/api/settings/{category-name}/{option-name}](#get-an-option) | Get a single setting option    |
+| PUT       | [/api/settings/{category-name}/{option-name}](#change-an-option-value) | Change the value of a setting option    |
+| DELETE    | [/api/settings/{category-name}/{option-name}](#delete-an-option) | Reset a setting option to its default   |
 
 
 
@@ -2264,7 +2265,7 @@ curl -X GET "http://localhost:3689/api/settings/webinterface"
 ```
 
 
-### Get a option
+### Get an option
 
 Get a single settings option
 
@@ -2294,7 +2295,7 @@ curl -X GET "http://localhost:3689/api/settings/webinterface/show_composer_now_p
 ```
 
 
-### Change a option value
+### Change an option value
 
 Get a single settings option
 
@@ -2323,6 +2324,28 @@ curl -X PUT "http://localhost:3689/api/settings/webinterface/show_composer_now_p
 ```
 
 
+### Delete an option
+
+Delete a single settings option (thus resetting it to default)
+
+**Endpoint**
+
+```http
+DELETE /api/settings/{category-name}/{option-name}
+```
+
+**Response**
+
+On success returns the HTTP `204 No Content` success status response code.
+
+
+**Example**
+
+```shell
+curl -X DELETE "http://localhost:3689/api/settings/webinterface/show_composer_now_playing"
+```
+
+
 ## Push notifications
 
 If forked-daapd was built with websocket support, forked-daapd exposes a websocket at `localhost:3688` to inform clients of changes (e. g. player state or library updates).

src/httpd_jsonapi.c

@@ -998,6 +998,43 @@ jsonapi_reply_settings_option_put(struct httpd_request *hreq)
   return HTTP_NOCONTENT;
 }
 
+static int
+jsonapi_reply_settings_option_delete(struct httpd_request *hreq)
+{
+  const char *categoryname;
+  const char *optionname;
+  struct settings_category *category;
+  struct settings_option *option;
+  int ret;
+
+
+  categoryname = hreq->uri_parsed->path_parts[2];
+  optionname = hreq->uri_parsed->path_parts[3];
+
+  category = settings_category_get(categoryname);
+  if (!category)
+    {
+      DPRINTF(E_LOG, L_WEB, "Invalid category name '%s' given\n", categoryname);
+      return HTTP_NOTFOUND;
+    }
+
+  option = settings_option_get(category, optionname);
+  if (!option)
+    {
+      DPRINTF(E_LOG, L_WEB, "Invalid option name '%s' given\n", optionname);
+      return HTTP_NOTFOUND;
+    }
+
+  ret = settings_option_delete(option);
+  if (ret < 0)
+    {
+      DPRINTF(E_LOG, L_WEB, "Error deleting option '%s'\n", optionname);
+      return HTTP_INTERNAL;
+    }
+
+  return HTTP_NOCONTENT;
+}
+
 /*
  * Endpoint to retrieve informations about the library
  *
@@ -4167,6 +4204,7 @@ static struct httpd_uri_map adm_handlers[] =
     { EVHTTP_REQ_GET,    "^/api/settings/[A-Za-z0-9_]+$",                jsonapi_reply_settings_category_get },
     { EVHTTP_REQ_GET,    "^/api/settings/[A-Za-z0-9_]+/[A-Za-z0-9_]+$",  jsonapi_reply_settings_option_get },
     { EVHTTP_REQ_PUT,    "^/api/settings/[A-Za-z0-9_]+/[A-Za-z0-9_]+$",  jsonapi_reply_settings_option_put },
+    { EVHTTP_REQ_DELETE, "^/api/settings/[A-Za-z0-9_]+/[A-Za-z0-9_]+$",  jsonapi_reply_settings_option_delete },
     { EVHTTP_REQ_GET,    "^/api/library$",                               jsonapi_reply_library },
     { EVHTTP_REQ_GET |
       EVHTTP_REQ_PUT,    "^/api/update$",                                jsonapi_reply_update },

src/settings.c

@@ -241,3 +241,12 @@ settings_option_setstr(struct settings_option *option, const char *value)
 
   return db_admin_set(option->name, value);
 }
+
+int
+settings_option_delete(struct settings_option *option)
+{
+  if (!option)
+    return -1;
+
+  return db_admin_delete(option->name);
+}

src/settings.h

@@ -64,4 +64,7 @@ settings_option_setbool(struct settings_option *option, bool value);
 int
 settings_option_setstr(struct settings_option *option, const char *value);
 
+int
+settings_option_delete(struct settings_option *option);
+
 #endif /* __SETTINGS_H__ */