ARI: Added new functionality to get information on a single module.

An http request can be sent to retrieve information on a single
module, including the resource name, description, use count, status,
and support level.

The command "curl -v -u user:pass -X GET 'http://localhost:8088/ari
/asterisk/modules/{moduleName}'" (or something similar, depending on
configuration) can be run in the terminal to access this new
functionality.

For more information, see:
https://wiki.asterisk.org/wiki.display/~bford/Asterisk+ARI+Resource

* Added new ARI functionality
* Information on a single module can now be retrieved

ASTERISK-25173

Change-Id: Ibce5a94e70ecdf4e90329cf0ba66c33a62d37463

7 files changed, 239 insertions, 3 deletions

diff --git a/CHANGES b/CHANGES
index 7521777c5..dcec202fb 100644
--- a/CHANGES
+++ b/CHANGES
@@ -192,7 +192,8 @@ AMI
 ARI
 ------------------
  * A new feature has been added that enables the retrieval of modules and
-   module information through an HTTP request.
+   module information through an HTTP request. Information on a single module
+   can be also be retrieved.
 
 res_pjsip
 ------------------
diff --git a/include/asterisk/module.h b/include/asterisk/module.h
index 59e6c7ed5..9fbeb5ebc 100644
--- a/include/asterisk/module.h
+++ b/include/asterisk/module.h
@@ -179,6 +179,25 @@ int ast_update_module_list_data(int (*modentry)(const char *module, const char *
                                 const char *like, void *data);
 
 /*!
+ * \brief Ask for a list of modules, descriptions, use counts and status.
+ * \param modentry A callback to an updater function
+ * \param like
+ * \param data Data passed into the callback for manipulation
+ * \param condition The condition to meet
+ *
+ * For each of the modules loaded, modentry will be executed with the resource,
+ * description, and usecount values of each particular module.
+ *
+ * \return the number of conditions met
+ * \since 13.5.0
+ */
+int ast_update_module_list_condition(int (*modentry)(const char *module, const char *description,
+                                                     int usecnt, const char *status, const char *like,
+                                                     enum ast_module_support_level support_level,
+                                                     void *data, const char *condition),
+                                     const char *like, void *data, const char *condition);
+
+/*!
  * \brief Check if module with the name given is loaded
  * \param name Module name, like "chan_sip.so"
  * \retval 1 if true 
diff --git a/main/loader.c b/main/loader.c
index 99a47b3b4..b2bdd4a3d 100644
--- a/main/loader.c
+++ b/main/loader.c
@@ -1445,6 +1445,34 @@ int ast_update_module_list_data(int (*modentry)(const char *module, const char *
 	return total_mod_loaded;
 }
 
+int ast_update_module_list_condition(int (*modentry)(const char *module, const char *description,
+                                                     int usecnt, const char *status,
+                                                     const char *like,
+                                                     enum ast_module_support_level support_level,
+                                                     void *data, const char *condition),
+                                     const char *like, void *data, const char *condition)
+{
+	struct ast_module *cur;
+	int conditions_met = 0;
+	AST_LIST_HEAD_NOLOCK(, ast_module) alpha_module_list = AST_LIST_HEAD_NOLOCK_INIT_VALUE;
+
+	AST_DLLIST_LOCK(&module_list);
+
+	AST_DLLIST_TRAVERSE(&module_list, cur, entry) {
+		AST_LIST_INSERT_SORTALPHA(&alpha_module_list, cur, list_entry, resource);
+	}
+
+	while ((cur = AST_LIST_REMOVE_HEAD(&alpha_module_list, list_entry))) {
+		conditions_met += modentry(cur->resource, cur->info->description, cur->usecount,
+		        cur->flags.running? "Running" : "Not Running", like, cur->info->support_level, data,
+		        condition);
+	}
+
+	AST_DLLIST_UNLOCK(&module_list);
+
+	return conditions_met;
+}
+
 /*! \brief Check if module exists */
 int ast_module_check(const char *name)
 {
diff --git a/res/ari/resource_asterisk.c b/res/ari/resource_asterisk.c
index cc80d0ca3..ea1a073b0 100644
--- a/res/ari/resource_asterisk.c
+++ b/res/ari/resource_asterisk.c
@@ -185,6 +185,79 @@ void ast_ari_asterisk_list_modules(struct ast_variable *headers,
 	ast_ari_response_ok(response, json);
 }
 
+/*!
+ * \brief Identify module by name and process resource information
+ * \param module Resource name
+ * \param description Resource description
+ * \param usecnt Resource use count
+ * \param status Resource running status
+ * \param like
+ * \param support_level Resource support level
+ * \param data JSON body for resource
+ * \param condition Name to match resource to
+ *
+ * \retval 0 if no resource exists
+ * \retval 1 if resource exists
+ */
+static int identify_module(const char *module, const char *description, int usecnt,
+                           const char *status, const char *like,
+                           enum ast_module_support_level support_level, void *data,
+                           const char *condition)
+{
+	int json_obj_set = 0;
+
+	if (strcmp(condition, module) != 0) {
+		return 0;
+	}
+
+	json_obj_set += ast_json_object_set(data, "name", ast_json_string_create(module));
+	json_obj_set += ast_json_object_set(data, "description", ast_json_string_create(description));
+	json_obj_set += ast_json_object_set(data, "use_count", ast_json_integer_create(usecnt));
+	json_obj_set += ast_json_object_set(data, "status", ast_json_string_create(status));
+	json_obj_set += ast_json_object_set(data, "support_level", ast_json_string_create(
+	                                    ast_module_support_level_to_string(support_level)));
+
+	if (json_obj_set != 0) {
+		return 0;
+	}
+
+	return 1;
+}
+
+void ast_ari_asterisk_get_module(struct ast_variable *headers,
+	struct ast_ari_asterisk_get_module_args *args,
+	struct ast_ari_response *response)
+{
+	struct ast_json *json;
+	int module_retrieved = 0;
+
+	ast_assert(response != NULL);
+
+	if (!ast_module_check(args->module_name)) {
+		ast_ari_response_error(
+			response, 404, "Not Found",
+			"Module could not be found in running modules");
+		return;
+	}
+
+	json = ast_json_object_create();
+	if (!json) {
+		ast_ari_response_alloc_failed(response);
+		return;
+	}
+
+	module_retrieved = ast_update_module_list_condition(&identify_module, NULL, json,
+	                                                    args->module_name);
+	if (!module_retrieved) {
+		ast_ari_response_error(
+			response, 409, "Conflict",
+			"Module information could not be retrieved");
+		return;
+	}
+
+	ast_ari_response_ok(response, json);
+}
+
 void ast_ari_asterisk_get_global_var(struct ast_variable *headers,
 	struct ast_ari_asterisk_get_global_var_args *args,
 	struct ast_ari_response *response)
diff --git a/res/ari/resource_asterisk.h b/res/ari/resource_asterisk.h
index b09d2715a..8689f3ec1 100644
--- a/res/ari/resource_asterisk.h
+++ b/res/ari/resource_asterisk.h
@@ -78,6 +78,19 @@ struct ast_ari_asterisk_list_modules_args {
  * \param[out] response HTTP response
  */
 void ast_ari_asterisk_list_modules(struct ast_variable *headers, struct ast_ari_asterisk_list_modules_args *args, struct ast_ari_response *response);
+/*! Argument struct for ast_ari_asterisk_get_module() */
+struct ast_ari_asterisk_get_module_args {
+	/*! Module's name */
+	const char *module_name;
+};
+/*!
+ * \brief Get Asterisk module information.
+ *
+ * \param headers HTTP headers
+ * \param args Swagger parameters
+ * \param[out] response HTTP response
+ */
+void ast_ari_asterisk_get_module(struct ast_variable *headers, struct ast_ari_asterisk_get_module_args *args, struct ast_ari_response *response);
 /*! Argument struct for ast_ari_asterisk_get_global_var() */
 struct ast_ari_asterisk_get_global_var_args {
 	/*! The variable to get */
diff --git a/res/res_ari_asterisk.c b/res/res_ari_asterisk.c
index fb4207aab..214bb2fea 100644
--- a/res/res_ari_asterisk.c
+++ b/res/res_ari_asterisk.c
@@ -260,6 +260,66 @@ static void ast_ari_asterisk_list_modules_cb(
 fin: __attribute__((unused))
 	return;
 }
+/*!
+ * \brief Parameter parsing callback for /asterisk/modules/{moduleName}.
+ * \param get_params GET parameters in the HTTP request.
+ * \param path_vars Path variables extracted from the request.
+ * \param headers HTTP headers.
+ * \param[out] response Response to the HTTP request.
+ */
+static void ast_ari_asterisk_get_module_cb(
+	struct ast_tcptls_session_instance *ser,
+	struct ast_variable *get_params, struct ast_variable *path_vars,
+	struct ast_variable *headers, struct ast_ari_response *response)
+{
+	struct ast_ari_asterisk_get_module_args args = {};
+	struct ast_variable *i;
+	RAII_VAR(struct ast_json *, body, NULL, ast_json_unref);
+#if defined(AST_DEVMODE)
+	int is_valid;
+	int code;
+#endif /* AST_DEVMODE */
+
+	for (i = path_vars; i; i = i->next) {
+		if (strcmp(i->name, "moduleName") == 0) {
+			args.module_name = (i->value);
+		} else
+		{}
+	}
+	ast_ari_asterisk_get_module(headers, &args, response);
+#if defined(AST_DEVMODE)
+	code = response->response_code;
+
+	switch (code) {
+	case 0: /* Implementation is still a stub, or the code wasn't set */
+		is_valid = response->message == NULL;
+		break;
+	case 500: /* Internal Server Error */
+	case 501: /* Not Implemented */
+	case 404: /* Module could not be found in running modules. */
+	case 409: /* Module information could not be retrieved. */
+		is_valid = 1;
+		break;
+	default:
+		if (200 <= code && code <= 299) {
+			is_valid = ast_ari_validate_module(
+				response->message);
+		} else {
+			ast_log(LOG_ERROR, "Invalid error response %d for /asterisk/modules/{moduleName}\n", code);
+			is_valid = 0;
+		}
+	}
+
+	if (!is_valid) {
+		ast_log(LOG_ERROR, "Response validation failed for /asterisk/modules/{moduleName}\n");
+		ast_ari_response_error(response, 500,
+			"Internal Server Error", "Response validation failed");
+	}
+#endif /* AST_DEVMODE */
+
+fin: __attribute__((unused))
+	return;
+}
 int ast_ari_asterisk_get_global_var_parse_body(
 	struct ast_json *body,
 	struct ast_ari_asterisk_get_global_var_args *args)
@@ -460,13 +520,23 @@ static struct stasis_rest_handlers asterisk_info = {
 	.children = {  }
 };
 /*! \brief REST handler for /api-docs/asterisk.{format} */
+static struct stasis_rest_handlers asterisk_modules_moduleName = {
+	.path_segment = "moduleName",
+	.is_wildcard = 1,
+	.callbacks = {
+		[AST_HTTP_GET] = ast_ari_asterisk_get_module_cb,
+	},
+	.num_children = 0,
+	.children = {  }
+};
+/*! \brief REST handler for /api-docs/asterisk.{format} */
 static struct stasis_rest_handlers asterisk_modules = {
 	.path_segment = "modules",
 	.callbacks = {
 		[AST_HTTP_GET] = ast_ari_asterisk_list_modules_cb,
 	},
-	.num_children = 0,
-	.children = {  }
+	.num_children = 1,
+	.children = { &asterisk_modules_moduleName, }
 };
 /*! \brief REST handler for /api-docs/asterisk.{format} */
 static struct stasis_rest_handlers asterisk_variable = {
diff --git a/rest-api/api-docs/asterisk.json b/rest-api/api-docs/asterisk.json
index ade5938c9..76c834e45 100644
--- a/rest-api/api-docs/asterisk.json
+++ b/rest-api/api-docs/asterisk.json
@@ -51,6 +51,38 @@
 			]
 		},
 		{
+			"path": "/asterisk/modules/{moduleName}",
+			"description": "Asterisk module",
+			"operations": [
+				{
+					"httpMethod": "GET",
+					"summary": "Get Asterisk module information.",
+					"nickname": "getModule",
+					"responseClass": "Module",
+					"parameters": [
+						{
+							"name": "moduleName",
+							"description": "Module's name",
+							"paramType": "path",
+							"required": true,
+							"allowMultiple": false,
+							"dataType": "string"
+						}
+					],
+					"errorResponses": [
+						{
+							"code": 404,
+							"reason": "Module could not be found in running modules."
+						},
+						{
+							"code": 409,
+							"reason": "Module information could not be retrieved."
+						}
+					]
+				}
+			]
+		},
+		{
 			"path": "/asterisk/variable",
 			"description": "Global variables",
 			"operations": [