caf: modules: added shell module to common application framework

Added a shell module to the Common Application Framework, and
added a custom command to that shell to simulate button press
event.

Signed-off-by: Tony Le <tony.le@nordicsemi.no>

doc/nrf/libraries/caf/caf_shell.rst

@@ -0,0 +1,38 @@
+.. _caf_shell:
+
+CAF: Shell module
+#################
+
+.. contents::
+   :local:
+   :depth: 2
+
+The shell module of the :ref:`lib_caf` (CAF) allows interactions with CAF modules and events using a predefined set of Zephyr's :ref:`zephyr:shell_api` commands.
+The module introduces a shell command for submitting events informing about button press or release (:c:struct:`button_event`).
+Submitting :c:struct:`button_event` related to the hardware button presses can be handled by the :ref:`caf_buttons`.
+
+Configuration
+*************
+
+To use the module, enable the following Kconfig options:
+
+* :kconfig:option:`CONFIG_CAF_SHELL` - This option is mandatory as it enables this module.
+* :kconfig:option:`CONFIG_SHELL` - This option enables Zephyr shell that is used by the module to receive commands from user.
+* :kconfig:option:`CONFIG_CAF` - This option enables the Common Application Framework.
+
+This module selects the Kconfig option :kconfig:option:`CONFIG_CAF_BUTTON_EVENTS`.
+
+Usage
+*****
+
+All shell commands of this module are subcommands of the :command:`caf_events` command.
+To send a :c:struct:`button_event`, use the following syntax:
+
+  .. code-block:: console
+
+     caf_events button_event [button_id] [pressed]
+
+The :command:`button_event` subcommand has two required arguments:
+
+* ``button_id`` - A decimal number represents the ID of a button.
+* ``pressed`` - Button press state, can only be either ``y`` or ``n``.

doc/nrf/releases_and_maturity/releases/release-notes-changelog.rst

@@ -742,6 +742,8 @@ Other libraries
 Common Application Framework (CAF)
 ----------------------------------
 
+* Added :ref:`caf_shell` for triggering CAF events.
+
 * :ref:`caf_buttons`:
 
   * Added selective wakeup functionality.

subsys/caf/modules/CMakeLists.txt

@@ -37,4 +37,7 @@ zephyr_library_sources_ifdef(CONFIG_CAF_SENSOR_DATA_AGGREGATOR sensor_data_aggre
 zephyr_library_sources_ifdef(CONFIG_CAF_SETTINGS_LOADER settings_loader.c)
 
 zephyr_library_sources_ifdef(CONFIG_CAF_BLE_SMP ble_smp.c)
+
+zephyr_library_sources_ifdef(CONFIG_CAF_SHELL caf_shell.c)
+
 zephyr_library_link_libraries_ifdef(CONFIG_MCUMGR mgmt_mcumgr)

subsys/caf/modules/Kconfig

@@ -17,3 +17,4 @@ rsource "Kconfig.power_manager"
 rsource "Kconfig.sensor_data_aggregator"
 rsource "Kconfig.sensor_manager"
 rsource "Kconfig.settings_loader"
+rsource "Kconfig.caf_shell"

subsys/caf/modules/Kconfig.caf_shell

@@ -0,0 +1,18 @@
+#
+# Copyright (c) 2023 Nordic Semiconductor ASA
+#
+# SPDX-License-Identifier: LicenseRef-Nordic-5-Clause
+#
+
+menuconfig CAF_SHELL
+	bool "Shell interface for triggering CAF events"
+	depends on SHELL
+	select CAF_BUTTON_EVENTS
+
+if CAF_SHELL
+
+module = CAF_SHELL
+module-str = caf shell
+source "subsys/logging/Kconfig.template.log_config"
+
+endif # CAF_SHELL

subsys/caf/modules/caf_shell.c

@@ -0,0 +1,49 @@
+/*
+ * Copyright (c) 2023 Nordic Semiconductor ASA
+ *
+ * SPDX-License-Identifier: LicenseRef-Nordic-5-Clause
+ */
+
+#include <stdlib.h>
+#include <zephyr/shell/shell.h>
+#include <caf/events/button_event.h>
+
+static const char button_event_cmd_help_str[] =
+	"Submit a button_event with user-defined key ID and pressed state\n"
+	"  Key ID           Decimal numeric ID of the button\n"
+	"  Pressed state    'y' or 'n'\n";
+
+static int button_event_handler(const struct shell *shell, size_t argc, char **argv)
+{
+	/* The string part of button_id param, for invalidation check */
+	char *str_part;
+
+	/* Convert button_id from string to decimal number */
+	long button_id = strtol(argv[1], &str_part, 10);
+
+	if (strlen(str_part) > 0 || button_id < 0 || button_id > UINT16_MAX) {
+		shell_error(shell, "Invalid key ID");
+		return -EINVAL;
+	}
+
+	if ((strlen(argv[2]) > 1) || (*argv[2] != 'y' && *argv[2] != 'n')) {
+		shell_error(shell, "Invalid button press state");
+		return -EINVAL;
+	}
+
+	struct button_event *event = new_button_event();
+
+	event->key_id = (uint16_t)button_id;
+	event->pressed = *argv[2] != 'n';
+	APP_EVENT_SUBMIT(event);
+
+	return 0;
+}
+
+SHELL_STATIC_SUBCMD_SET_CREATE(sub_caf_shell_command,
+	SHELL_CMD_ARG(button_event, NULL, button_event_cmd_help_str, button_event_handler, 3, 0),
+	SHELL_SUBCMD_SET_END
+);
+
+SHELL_CMD_REGISTER(caf_events, &sub_caf_shell_command,
+	"Submit a CAF event with user-defined parameters", NULL);