Initial commit for nrf/samples/nrf9160/mqtt_simple

12 files changed, 1076 insertions, 0 deletions

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..635a99b
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,6 @@
+# editors
+*.swp
+*~
+
+# build
+/build*/
diff --git a/CMakeLists.txt b/CMakeLists.txt
new file mode 100644
index 0000000..8fe58a9
--- /dev/null
+++ b/CMakeLists.txt
@@ -0,0 +1,14 @@
+#
+# Copyright (c) 2018 Nordic Semiconductor ASA
+#
+# SPDX-License-Identifier: LicenseRef-Nordic-5-Clause
+#
+
+cmake_minimum_required(VERSION 3.20.0)
+
+find_package(Zephyr REQUIRED HINTS $ENV{ZEPHYR_BASE})
+project(mqtt-simple)
+
+# NORDIC SDK APP START
+target_sources(app PRIVATE src/main.c)
+# NORDIC SDK APP END
diff --git a/Kconfig b/Kconfig
new file mode 100644
index 0000000..c486dd4
--- /dev/null
+++ b/Kconfig
@@ -0,0 +1,78 @@
+#
+# Copyright (c) 2020 Nordic Semiconductor ASA
+#
+# SPDX-License-Identifier: LicenseRef-Nordic-5-Clause
+#
+
+menu "MQTT simple sample"
+config MQTT_PUB_TOPIC
+	string "MQTT publish topic"
+	default "my/publish/topic"
+
+config MQTT_SUB_TOPIC
+	string "MQTT subscribe topic"
+	default "my/subscribe/topic"
+
+config MQTT_CLIENT_ID
+	string "MQTT Client ID"
+	help
+	  Use a custom Client ID string. If not set, the client ID will be
+	  generated based on IMEI number (for nRF9160 based targets) or
+	  randomly (for other platforms).
+	default ""
+
+config MQTT_BROKER_HOSTNAME
+	string "MQTT broker hostname"
+	default "test.mosquitto.org"
+
+config MQTT_BROKER_PORT
+	int "MQTT broker port"
+	default 1883
+
+config MQTT_MESSAGE_BUFFER_SIZE
+	int "MQTT message buffer size"
+	default 128
+
+config MQTT_PAYLOAD_BUFFER_SIZE
+	int "MQTT payload buffer size"
+	default 128
+
+config BUTTON_EVENT_PUBLISH_MSG
+	string "The message to publish on a button event"
+	default "Hello from nRF91 MQTT Simple Sample"
+
+config BUTTON_EVENT_BTN_NUM
+	int "The button number"
+	default 1
+
+config MQTT_RECONNECT_DELAY_S
+	int "Seconds to delay before attempting to reconnect to the broker"
+	default 60
+
+config LTE_CONNECT_RETRY_DELAY_S
+	int "Seconds to delay before attempting to retry LTE connection"
+	default 120
+
+config MQTT_TLS_SEC_TAG
+	int "TLS credentials security tag"
+	default 24
+
+config MQTT_TLS_SESSION_CACHING
+	bool "Enable TLS session caching"
+
+config MQTT_TLS_PEER_VERIFY
+	int "Set peer verification level"
+	default 2
+	help
+		Set to 0 for VERIFY_NONE, 1 for VERIFY_OPTIONAL, and 2 for
+		VERIFY_REQUIRED.
+
+endmenu
+
+menu "Zephyr Kernel"
+source "Kconfig.zephyr"
+endmenu
+
+module = MQTT_SIMPLE
+module-str = MQTT Simple
+source "${ZEPHYR_BASE}/subsys/logging/Kconfig.template.log_config"
diff --git a/README.rst b/README.rst
new file mode 100644
index 0000000..e10c3dd
--- /dev/null
+++ b/README.rst
@@ -0,0 +1,188 @@
+.. _mqtt_simple_sample:
+
+nRF9160: Simple MQTT
+####################
+
+.. contents::
+   :local:
+   :depth: 2
+
+The Simple MQTT sample demonstrates how to easily connect an nRF9160 SiP to an MQTT broker and send and receive data.
+
+Requirements
+************
+
+The sample supports the following development kit:
+
+.. table-from-sample-yaml::
+
+Additionally, the sample supports :ref:`qemu_x86`.
+
+.. include:: /includes/tfm.txt
+
+Overview
+*********
+
+The sample connects to an MQTT broker and publishes the data it receives on the configured subscribe topic to the configured publish topic.
+On a button press event or typing ``mqtt publish`` in the terminal emulator, the sample publishes the configured message to the configured publish topic.
+By default, the sample can establish a secure (TLS) connection or a non-secure connection to the configured MQTT broker.
+The sample disables power saving modes (PSM and eDRX) so that network events are processed as soon as possible.
+
+Configuration
+*************
+
+|config|
+
+Configuration options
+=====================
+
+Check and configure the following configuration options for the sample:
+
+.. _CONFIG_MQTT_BROKER_HOSTNAME:
+
+CONFIG_MQTT_BROKER_HOSTNAME - MQTT Broker host name
+   This configuration option defines the MQTT Broker host name.
+
+.. _CONFIG_MQTT_CLIENT_ID:
+
+CONFIG_MQTT_CLIENT_ID - MQTT Client ID
+   This configuration option specifies the MQTT Client ID.
+
+.. _CONFIG_MQTT_SUB_TOPIC:
+
+CONFIG_MQTT_SUB_TOPIC - MQTT Subscribe topic
+   This configuration option sets the MQTT Subscribe topic.
+
+.. _CONFIG_MQTT_PUB_TOPIC:
+
+CONFIG_MQTT_PUB_TOPIC - MQTT Publish topic
+   This configuration option sets the MQTT Publish topic.
+
+.. _CONFIG_MQTT_BROKER_PORT:
+
+CONFIG_MQTT_BROKER_PORT - MQTT Broker Port
+   This configuration option specifies the port number associated with the MQTT broker.
+
+.. _CONFIG_BUTTON_EVENT_PUBLISH_MSG:
+
+CONFIG_BUTTON_EVENT_PUBLISH_MSG - Button event publish message
+   This configuration option specifies the message text which is published on a button press.
+
+.. _CONFIG_BUTTON_EVENT_BTN_NUM:
+
+CONFIG_BUTTON_EVENT_BTN_NUM - Button number for publish
+   This configuration option specifies the button number which, when pressed, will publish an MQTT message.
+
+.. _CONFIG_MQTT_RECONNECT_DELAY_S:
+
+CONFIG_MQTT_RECONNECT_DELAY_S - MQTT broker reconnect delay
+   This configuration option specifies the delay (in seconds) before attempting to reconnect to the broker.
+
+.. _CONFIG_LTE_CONNECT_RETRY_DELAY_S:
+
+CONFIG_LTE_CONNECT_RETRY_DELAY_S - LTE connection retry delay
+   This configuration option specifies delay (in seconds) before attempting to retry LTE connection.
+
+Configuration files
+=====================
+
+The sample provides the following predefined configuration files for the following development kits:
+
+* :file:`prj.conf` - For nRF9160 DK
+* :file:`prj_qemu_x86.conf` - For x86 Emulation (QEMU)
+
+In addition, the sample provides overlay configuration files, which are used to enable additional features in the sample:
+
+* :file:`overlay-tls.conf` - TLS overlay configuration file for nRF9160 DK
+* :file:`overlay-qemu-x86-tls.conf` - TLS overlay configuration file for x86 Emulation (QEMU)
+
+They are located in :file:`samples/nrf9160/mqtt_simple` folder.
+
+
+To add a specific overlay configuration file to the build, add the ``-- -DOVERLAY_CONFIG=<overlay_config_file>`` flag to your build.
+
+See :ref:`cmake_options` for instructions on how to add this option to your build.
+For example, when building on the command line, you can build the sample with the TLS configuration for nRF9160 DK as follows:
+
+  .. code-block:: console
+
+     west build -b nrf9160dk_nrf9160_ns -- -DOVERLAY_CONFIG=overlay-tls.conf
+
+.. note::
+   The CA certificate for the default MQTT broker is included in the project and automatically provisioned after boot if the sample is built with the TLS configuration.
+
+Building and running
+********************
+
+.. |sample path| replace:: :file:`samples/nrf9160/mqtt_simple`
+
+.. include:: /includes/build_and_run_ns.txt
+
+Testing
+=======
+
+|test_sample|
+
+1. |connect_kit|
+#. |connect_terminal|
+#. Reset your nRF9160 DK.
+#. Observe that the sample displays the following information in the terminal::
+
+       The MQTT simple sample started
+#. Observe that the development kit connects to the configured MQTT broker (:ref:`CONFIG_MQTT_BROKER_HOSTNAME <CONFIG_MQTT_BROKER_HOSTNAME>`) after it gets the LTE connection.
+   At this stage, the development kit is ready to echo the data sent to it on the configured subscribe topic (:ref:`CONFIG_MQTT_SUB_TOPIC <CONFIG_MQTT_SUB_TOPIC>`).
+#. Use an MQTT client like `Mosquitto`_ to subscribe to and publish data to the broker.
+   Observe that the development kit publishes all the data that you publish to :ref:`CONFIG_MQTT_SUB_TOPIC <CONFIG_MQTT_SUB_TOPIC>` on :ref:`CONFIG_MQTT_PUB_TOPIC <CONFIG_MQTT_PUB_TOPIC>`.
+
+Sample output
+=============
+
+The following serial UART output is displayed in the terminal emulator:
+
+.. code-block:: console
+
+      *** Booting Zephyr OS build v2.4.0-ncs1-rc1-6-g45f2d5cf8ea4  ***
+      <inf> mqtt_simple: The MQTT simple sample started
+      <inf> mqtt_simple: LTE Link Connecting...
+      <inf> mqtt_simple: LTE Link Connected!
+      <inf> mqtt_simple: Disabling PSM and eDRX
+      <inf> mqtt_simple: IPv4 Address found 137.135.83.217
+      <inf> mqtt_simple: MQTT client connected
+      <inf> mqtt_simple: Subscribing to: my/subscribe/topic len 18
+      <inf> mqtt_simple: SUBACK packet id: 1234
+      <inf> mqtt_simple: Publishing: Hello from nRF91 MQTT Simple Sample
+      <inf> mqtt_simple: to topic: my/publish/topic len: 16
+      <inf> mqtt_simple: PUBACK packet id: 51700
+
+
+
+Troubleshooting
+===============
+
+Public MQTT brokers might be unstable.
+If you experience problems connecting to the MQTT broker, try switching to another MQTT broker by changing the value of the :ref:`CONFIG_MQTT_BROKER_HOSTNAME <CONFIG_MQTT_BROKER_HOSTNAME>` configuration option.
+
+.. note::
+   If the :ref:`CONFIG_MQTT_BROKER_HOSTNAME <CONFIG_MQTT_BROKER_HOSTNAME>` configuration option is changed and the overlay TLS configuration is used, the included CA certificate must be updated with the CA certificate for
+   the newly configurated MQTT broker.
+
+
+Dependencies
+************
+
+This sample uses the following |NCS| library:
+
+* :ref:`lte_lc_readme`
+
+It uses the following `sdk-nrfxlib`_ library:
+
+* :ref:`nrfxlib:nrf_modem`
+
+It uses the following Zephyr library:
+
+* :ref:`MQTT <zephyr:networking_api>`
+* :ref:`zephyr:shell_api`
+
+In addition, it uses the following secure firmware component:
+
+* :ref:`Trusted Firmware-M <ug_tfm>`
diff --git a/overlay-qemu-x86-tls.conf b/overlay-qemu-x86-tls.conf
new file mode 100644
index 0000000..1e17556
--- /dev/null
+++ b/overlay-qemu-x86-tls.conf
@@ -0,0 +1,22 @@
+#
+# Copyright (c) 2020 Nordic Semiconductor ASA
+#
+# SPDX-License-Identifier: LicenseRef-Nordic-5-Clause
+#
+
+# MQTT TLS
+CONFIG_MQTT_LIB_TLS=y
+CONFIG_MQTT_BROKER_PORT=8883
+
+# MBED TLS
+CONFIG_MBEDTLS=y
+CONFIG_MBEDTLS_BUILTIN=y
+CONFIG_MBEDTLS_ENABLE_HEAP=y
+CONFIG_MBEDTLS_HEAP_SIZE=120000
+CONFIG_MBEDTLS_SSL_MAX_CONTENT_LEN=16384
+CONFIG_MBEDTLS_PEM_CERTIFICATE_FORMAT=y
+CONFIG_MBEDTLS_KEY_EXCHANGE_RSA_ENABLED=y
+CONFIG_MBEDTLS_MAC_SHA256_ENABLED=y
+
+# NET SOCKETS
+CONFIG_NET_SOCKETS_SOCKOPT_TLS=y
diff --git a/overlay-tls.conf b/overlay-tls.conf
new file mode 100644
index 0000000..9a58e44
--- /dev/null
+++ b/overlay-tls.conf
@@ -0,0 +1,13 @@
+#
+# Copyright (c) 2020 Nordic Semiconductor ASA
+#
+# SPDX-License-Identifier: LicenseRef-Nordic-5-Clause
+#
+
+# MQTT TLS
+CONFIG_MQTT_LIB_TLS=y
+CONFIG_MQTT_BROKER_PORT=8886
+CONFIG_MQTT_KEEPALIVE=30
+
+# Modem key management, for provisioning certificates
+CONFIG_MODEM_KEY_MGMT=y
diff --git a/prj.conf b/prj.conf
new file mode 100644
index 0000000..d992cc6
--- /dev/null
+++ b/prj.conf
@@ -0,0 +1,49 @@
+#
+# Copyright (c) 2020 Nordic Semiconductor ASA
+#
+# SPDX-License-Identifier: LicenseRef-Nordic-5-Clause
+#
+
+# Networking
+CONFIG_NETWORKING=y
+CONFIG_NET_NATIVE=n
+CONFIG_NET_SOCKETS_OFFLOAD=y
+CONFIG_NET_SOCKETS=y
+CONFIG_NET_SOCKETS_POSIX_NAMES=y
+
+# LTE link control
+CONFIG_LTE_LINK_CONTROL=y
+CONFIG_LTE_AUTO_INIT_AND_CONNECT=n
+
+# Modem library
+CONFIG_NRF_MODEM_LIB=y
+
+# MQTT
+CONFIG_MQTT_LIB=y
+CONFIG_MQTT_LIB_TLS=n
+CONFIG_MQTT_CLEAN_SESSION=y
+
+# Application
+# CONFIG_MQTT_PUB_TOPIC="my/publish/topic"
+# CONFIG_MQTT_SUB_TOPIC="my/subscribe/topic"
+# CONFIG_MQTT_CLIENT_ID="my-client-id"
+# CONFIG_MQTT_BROKER_HOSTNAME="test.mosquitto.org"
+# CONFIG_MQTT_BROKER_PORT=1883
+
+# Button support
+CONFIG_DK_LIBRARY=y
+
+# Enable logging
+CONFIG_LOG=y
+CONFIG_MQTT_SIMPLE_LOG_LEVEL_DBG=y
+
+# Memory
+CONFIG_MAIN_STACK_SIZE=4096
+CONFIG_HEAP_MEM_POOL_SIZE=2048
+
+# NewLib C
+CONFIG_NEWLIB_LIBC=y
+
+# Shell support
+CONFIG_SHELL=y
+CONFIG_HW_ID_LIBRARY=y
diff --git a/prj_qemu_x86.conf b/prj_qemu_x86.conf
new file mode 100644
index 0000000..cf5863e
--- /dev/null
+++ b/prj_qemu_x86.conf
@@ -0,0 +1,43 @@
+#
+# Copyright (c) 2020 Nordic Semiconductor ASA
+#
+# SPDX-License-Identifier: LicenseRef-Nordic-5-Clause
+#
+
+# General config
+CONFIG_TEST_RANDOM_GENERATOR=y
+CONFIG_NEWLIB_LIBC=y
+CONFIG_LOG=y
+
+# MQTT
+CONFIG_MQTT_LIB=y
+CONFIG_MQTT_LIB_TLS=n
+
+# Networking config
+CONFIG_NETWORKING=y
+CONFIG_NET_IPV4=y
+CONFIG_NET_TCP=y
+CONFIG_NET_SOCKETS=y
+CONFIG_NET_SOCKETS_POSIX_NAMES=y
+
+CONFIG_DNS_RESOLVER=y
+CONFIG_DNS_SERVER_IP_ADDRESSES=y
+CONFIG_DNS_SERVER1="8.8.8.8"
+
+# Network address config
+CONFIG_NET_CONFIG_SETTINGS=y
+CONFIG_NET_CONFIG_NEED_IPV4=y
+CONFIG_NET_CONFIG_MY_IPV4_ADDR="192.0.2.1"
+CONFIG_NET_CONFIG_PEER_IPV4_ADDR="192.0.2.2"
+CONFIG_NET_CONFIG_MY_IPV4_GW="192.0.2.2"
+
+# Application
+#CONFIG_MQTT_PUB_TOPIC="/my/publish/topic"
+#CONFIG_MQTT_SUB_TOPIC="/my/subscribe/topic"
+#CONFIG_MQTT_CLIENT_ID="my-client-id"
+#CONFIG_MQTT_BROKER_HOSTNAME="mqtt.eclipseprojects.io"
+#CONFIG_MQTT_BROKER_PORT=1883
+
+# Memory
+CONFIG_HEAP_MEM_POOL_SIZE=16384
+CONFIG_MAIN_STACK_SIZE=16384
diff --git a/sample.yaml b/sample.yaml
new file mode 100644
index 0000000..1f8a578
--- /dev/null
+++ b/sample.yaml
@@ -0,0 +1,9 @@
+sample:
+  name: mqtt simple sample
+tests:
+  sample.nrf9160.mqtt_simple:
+    build_only: true
+    integration_platforms:
+      - nrf9160dk_nrf9160_ns
+    platform_allow: nrf9160dk_nrf9160_ns
+    tags: ci_build
diff --git a/src/certificates.h b/src/certificates.h
new file mode 100644
index 0000000..aebb1e8
--- /dev/null
+++ b/src/certificates.h
@@ -0,0 +1,38 @@
+/*
+ * Copyright (c) 2020 Nordic Semiconductor ASA
+ *
+ * SPDX-License-Identifier: LicenseRef-Nordic-5-Clause
+ */
+
+/** CA certificate for test.mosquitto.org, Let’s Encrypt R3 */
+#define CA_CERTIFICATE \
+	"-----BEGIN CERTIFICATE-----\n" \
+	"MIIFFjCCAv6gAwIBAgIRAJErCErPDBinU/bWLiWnX1owDQYJKoZIhvcNAQELBQAw\n" \
+	"TzELMAkGA1UEBhMCVVMxKTAnBgNVBAoTIEludGVybmV0IFNlY3VyaXR5IFJlc2Vh\n" \
+	"cmNoIEdyb3VwMRUwEwYDVQQDEwxJU1JHIFJvb3QgWDEwHhcNMjAwOTA0MDAwMDAw\n" \
+	"WhcNMjUwOTE1MTYwMDAwWjAyMQswCQYDVQQGEwJVUzEWMBQGA1UEChMNTGV0J3Mg\n" \
+	"RW5jcnlwdDELMAkGA1UEAxMCUjMwggEiMA0GCSqGSIb3DQEBAQUAA4IBDwAwggEK\n" \
+	"AoIBAQC7AhUozPaglNMPEuyNVZLD+ILxmaZ6QoinXSaqtSu5xUyxr45r+XXIo9cP\n" \
+	"R5QUVTVXjJ6oojkZ9YI8QqlObvU7wy7bjcCwXPNZOOftz2nwWgsbvsCUJCWH+jdx\n" \
+	"sxPnHKzhm+/b5DtFUkWWqcFTzjTIUu61ru2P3mBw4qVUq7ZtDpelQDRrK9O8Zutm\n" \
+	"NHz6a4uPVymZ+DAXXbpyb/uBxa3Shlg9F8fnCbvxK/eG3MHacV3URuPMrSXBiLxg\n" \
+	"Z3Vms/EY96Jc5lP/Ooi2R6X/ExjqmAl3P51T+c8B5fWmcBcUr2Ok/5mzk53cU6cG\n" \
+	"/kiFHaFpriV1uxPMUgP17VGhi9sVAgMBAAGjggEIMIIBBDAOBgNVHQ8BAf8EBAMC\n" \
+	"AYYwHQYDVR0lBBYwFAYIKwYBBQUHAwIGCCsGAQUFBwMBMBIGA1UdEwEB/wQIMAYB\n" \
+	"Af8CAQAwHQYDVR0OBBYEFBQusxe3WFbLrlAJQOYfr52LFMLGMB8GA1UdIwQYMBaA\n" \
+	"FHm0WeZ7tuXkAXOACIjIGlj26ZtuMDIGCCsGAQUFBwEBBCYwJDAiBggrBgEFBQcw\n" \
+	"AoYWaHR0cDovL3gxLmkubGVuY3Iub3JnLzAnBgNVHR8EIDAeMBygGqAYhhZodHRw\n" \
+	"Oi8veDEuYy5sZW5jci5vcmcvMCIGA1UdIAQbMBkwCAYGZ4EMAQIBMA0GCysGAQQB\n" \
+	"gt8TAQEBMA0GCSqGSIb3DQEBCwUAA4ICAQCFyk5HPqP3hUSFvNVneLKYY611TR6W\n" \
+	"PTNlclQtgaDqw+34IL9fzLdwALduO/ZelN7kIJ+m74uyA+eitRY8kc607TkC53wl\n" \
+	"ikfmZW4/RvTZ8M6UK+5UzhK8jCdLuMGYL6KvzXGRSgi3yLgjewQtCPkIVz6D2QQz\n" \
+	"CkcheAmCJ8MqyJu5zlzyZMjAvnnAT45tRAxekrsu94sQ4egdRCnbWSDtY7kh+BIm\n" \
+	"lJNXoB1lBMEKIq4QDUOXoRgffuDghje1WrG9ML+Hbisq/yFOGwXD9RiX8F6sw6W4\n" \
+	"avAuvDszue5L3sz85K+EC4Y/wFVDNvZo4TYXao6Z0f+lQKc0t8DQYzk1OXVu8rp2\n" \
+	"yJMC6alLbBfODALZvYH7n7do1AZls4I9d1P4jnkDrQoxB3UqQ9hVl3LEKQ73xF1O\n" \
+	"yK5GhDDX8oVfGKF5u+decIsH4YaTw7mP3GFxJSqv3+0lUFJoi5Lc5da149p90Ids\n" \
+	"hCExroL1+7mryIkXPeFM5TgO9r0rvZaBFOvV2z0gp35Z0+L4WPlbuEjN/lxPFin+\n" \
+	"HlUjr8gRsI3qfJOQFy/9rKIJR0Y/8Omwt/8oTWgy1mdeHmmjk7j1nYsvC9JSQ6Zv\n" \
+	"MldlTTKB3zhThV1+XWYp6rjd5JW1zbVWEkLNxE7GJThEUG3szgBVGP7pSWTUTsqX\n" \
+	"nLRbwHOoq7hHwg==\n" \
+	"-----END CERTIFICATE-----"
diff --git a/src/main.c b/src/main.c
new file mode 100644
index 0000000..570c01d
--- /dev/null
+++ b/src/main.c
@@ -0,0 +1,603 @@
+/*
+ * Copyright (c) 2018 Nordic Semiconductor ASA
+ *
+ * SPDX-License-Identifier: LicenseRef-Nordic-5-Clause
+ */
+
+#include <zephyr/kernel.h>
+#include <stdio.h>
+#include <zephyr/drivers/uart.h>
+#include <string.h>
+#include <zephyr/random/rand32.h>
+#include <zephyr/net/mqtt.h>
+#include <zephyr/net/socket.h>
+#include <zephyr/shell/shell.h>
+#include <hw_id.h>
+#if defined(CONFIG_NRF_MODEM_LIB)
+#include <nrf_modem_at.h>
+#endif /* CONFIG_NRF_MODEM_LIB */
+#include <modem/lte_lc.h>
+#include <zephyr/logging/log.h>
+#if defined(CONFIG_MODEM_KEY_MGMT)
+#include <modem/modem_key_mgmt.h>
+#endif
+#include <dk_buttons_and_leds.h>
+
+#include "certificates.h"
+
+LOG_MODULE_REGISTER(mqtt_simple, CONFIG_MQTT_SIMPLE_LOG_LEVEL);
+
+/* Buffers for MQTT client. */
+static uint8_t rx_buffer[CONFIG_MQTT_MESSAGE_BUFFER_SIZE];
+static uint8_t tx_buffer[CONFIG_MQTT_MESSAGE_BUFFER_SIZE];
+static uint8_t payload_buf[CONFIG_MQTT_PAYLOAD_BUFFER_SIZE];
+
+/* The mqtt client struct */
+static struct mqtt_client client;
+
+/* MQTT Broker details. */
+static struct sockaddr_storage broker;
+
+/* File descriptor */
+static struct pollfd fds;
+
+#if defined(CONFIG_MQTT_LIB_TLS)
+static int certificates_provision(void)
+{
+	int err = 0;
+
+	LOG_INF("Provisioning certificates");
+
+#if defined(CONFIG_NRF_MODEM_LIB) && defined(CONFIG_MODEM_KEY_MGMT)
+
+	err = modem_key_mgmt_write(CONFIG_MQTT_TLS_SEC_TAG,
+				   MODEM_KEY_MGMT_CRED_TYPE_CA_CHAIN,
+				   CA_CERTIFICATE,
+				   strlen(CA_CERTIFICATE));
+	if (err) {
+		LOG_ERR("Failed to provision CA certificate: %d", err);
+		return err;
+	}
+
+#elif defined(CONFIG_BOARD_QEMU_X86) && defined(CONFIG_NET_SOCKETS_SOCKOPT_TLS)
+
+	err = tls_credential_add(CONFIG_MQTT_TLS_SEC_TAG,
+				 TLS_CREDENTIAL_CA_CERTIFICATE,
+				 CA_CERTIFICATE,
+				 sizeof(CA_CERTIFICATE));
+	if (err) {
+		LOG_ERR("Failed to register CA certificate: %d", err);
+		return err;
+	}
+
+#endif
+
+	return err;
+}
+#endif /* defined(CONFIG_MQTT_LIB_TLS) */
+
+/**@brief Function to print strings without null-termination
+ */
+static void data_print(uint8_t *prefix, uint8_t *data, size_t len)
+{
+	char buf[len + 1];
+
+	memcpy(buf, data, len);
+	buf[len] = 0;
+	LOG_INF("%s%s", (char *)prefix, (char *)buf);
+}
+
+/**@brief Function to publish data on the configured topic
+ */
+static int data_publish(struct mqtt_client *c, enum mqtt_qos qos,
+	uint8_t *data, size_t len)
+{
+	struct mqtt_publish_param param;
+
+	param.message.topic.qos = qos;
+	param.message.topic.topic.utf8 = CONFIG_MQTT_PUB_TOPIC;
+	param.message.topic.topic.size = strlen(CONFIG_MQTT_PUB_TOPIC);
+	param.message.payload.data = data;
+	param.message.payload.len = len;
+	param.message_id = sys_rand32_get();
+	param.dup_flag = 0;
+	param.retain_flag = 0;
+
+	data_print("Publishing: ", data, len);
+	LOG_INF("to topic: %s len: %u",
+		CONFIG_MQTT_PUB_TOPIC,
+		(unsigned int)strlen(CONFIG_MQTT_PUB_TOPIC));
+
+	return mqtt_publish(c, &param);
+}
+
+/**@brief Function to subscribe to the configured topic
+ */
+static int subscribe(void)
+{
+	struct mqtt_topic subscribe_topic = {
+		.topic = {
+			.utf8 = CONFIG_MQTT_SUB_TOPIC,
+			.size = strlen(CONFIG_MQTT_SUB_TOPIC)
+		},
+		.qos = MQTT_QOS_1_AT_LEAST_ONCE
+	};
+
+	const struct mqtt_subscription_list subscription_list = {
+		.list = &subscribe_topic,
+		.list_count = 1,
+		.message_id = 1234
+	};
+
+	LOG_INF("Subscribing to: %s len %u", CONFIG_MQTT_SUB_TOPIC,
+		(unsigned int)strlen(CONFIG_MQTT_SUB_TOPIC));
+
+	return mqtt_subscribe(&client, &subscription_list);
+}
+
+/**@brief Function to read the published payload.
+ */
+static int publish_get_payload(struct mqtt_client *c, size_t length)
+{
+	int ret;
+	int err = 0;
+
+	/* Return an error if the payload is larger than the payload buffer.
+	 * Note: To allow new messages, we have to read the payload before returning.
+	 */
+	if (length > sizeof(payload_buf)) {
+		err = -EMSGSIZE;
+	}
+
+	/* Truncate payload until it fits in the payload buffer. */
+	while (length > sizeof(payload_buf)) {
+		ret = mqtt_read_publish_payload_blocking(
+				c, payload_buf, (length - sizeof(payload_buf)));
+		if (ret == 0) {
+			return -EIO;
+		} else if (ret < 0) {
+			return ret;
+		}
+
+		length -= ret;
+	}
+
+	ret = mqtt_readall_publish_payload(c, payload_buf, length);
+	if (ret) {
+		return ret;
+	}
+
+	return err;
+}
+
+/**@brief MQTT client event handler
+ */
+void mqtt_evt_handler(struct mqtt_client *const c,
+		      const struct mqtt_evt *evt)
+{
+	int err;
+
+	switch (evt->type) {
+	case MQTT_EVT_CONNACK:
+		if (evt->result != 0) {
+			LOG_ERR("MQTT connect failed: %d", evt->result);
+			break;
+		}
+
+		LOG_INF("MQTT client connected");
+		subscribe();
+		break;
+
+	case MQTT_EVT_DISCONNECT:
+		LOG_INF("MQTT client disconnected: %d", evt->result);
+		break;
+
+	case MQTT_EVT_PUBLISH: {
+		const struct mqtt_publish_param *p = &evt->param.publish;
+
+		LOG_INF("MQTT PUBLISH result=%d len=%d",
+			evt->result, p->message.payload.len);
+		err = publish_get_payload(c, p->message.payload.len);
+
+		if (p->message.topic.qos == MQTT_QOS_1_AT_LEAST_ONCE) {
+			const struct mqtt_puback_param ack = {
+				.message_id = p->message_id
+			};
+
+			/* Send acknowledgment. */
+			mqtt_publish_qos1_ack(&client, &ack);
+		}
+
+		if (err >= 0) {
+			data_print("Received: ", payload_buf,
+				p->message.payload.len);
+			/* Echo back received data */
+			data_publish(&client, MQTT_QOS_1_AT_LEAST_ONCE,
+				payload_buf, p->message.payload.len);
+		} else if (err == -EMSGSIZE) {
+			LOG_ERR("Received payload (%d bytes) is larger than the payload buffer "
+				"size (%d bytes).",
+				p->message.payload.len, sizeof(payload_buf));
+		} else {
+			LOG_ERR("publish_get_payload failed: %d", err);
+			LOG_INF("Disconnecting MQTT client...");
+
+			err = mqtt_disconnect(c);
+			if (err) {
+				LOG_ERR("Could not disconnect: %d", err);
+			}
+		}
+	} break;
+
+	case MQTT_EVT_PUBACK:
+		if (evt->result != 0) {
+			LOG_ERR("MQTT PUBACK error: %d", evt->result);
+			break;
+		}
+
+		LOG_INF("PUBACK packet id: %u", evt->param.puback.message_id);
+		break;
+
+	case MQTT_EVT_SUBACK:
+		if (evt->result != 0) {
+			LOG_ERR("MQTT SUBACK error: %d", evt->result);
+			break;
+		}
+
+		LOG_INF("SUBACK packet id: %u", evt->param.suback.message_id);
+		break;
+
+	case MQTT_EVT_PINGRESP:
+		if (evt->result != 0) {
+			LOG_ERR("MQTT PINGRESP error: %d", evt->result);
+		}
+		break;
+
+	default:
+		LOG_INF("Unhandled MQTT event type: %d", evt->type);
+		break;
+	}
+}
+
+/**@brief Resolves the configured hostname and
+ * initializes the MQTT broker structure
+ */
+static int broker_init(void)
+{
+	int err;
+	struct addrinfo *result;
+	struct addrinfo *addr;
+	struct addrinfo hints = {
+		.ai_family = AF_INET,
+		.ai_socktype = SOCK_STREAM
+	};
+
+	err = getaddrinfo(CONFIG_MQTT_BROKER_HOSTNAME, NULL, &hints, &result);
+	if (err) {
+		LOG_ERR("getaddrinfo failed: %d", err);
+		return -ECHILD;
+	}
+
+	addr = result;
+
+	/* Look for address of the broker. */
+	while (addr != NULL) {
+		/* IPv4 Address. */
+		if (addr->ai_addrlen == sizeof(struct sockaddr_in)) {
+			struct sockaddr_in *broker4 =
+				((struct sockaddr_in *)&broker);
+			char ipv4_addr[NET_IPV4_ADDR_LEN];
+
+			broker4->sin_addr.s_addr =
+				((struct sockaddr_in *)addr->ai_addr)
+				->sin_addr.s_addr;
+			broker4->sin_family = AF_INET;
+			broker4->sin_port = htons(CONFIG_MQTT_BROKER_PORT);
+
+			inet_ntop(AF_INET, &broker4->sin_addr.s_addr,
+				  ipv4_addr, sizeof(ipv4_addr));
+			LOG_INF("IPv4 Address found %s", ipv4_addr);
+
+			break;
+		} else {
+			LOG_ERR("ai_addrlen = %u should be %u or %u",
+				(unsigned int)addr->ai_addrlen,
+				(unsigned int)sizeof(struct sockaddr_in),
+				(unsigned int)sizeof(struct sockaddr_in6));
+		}
+
+		addr = addr->ai_next;
+	}
+
+	/* Free the address. */
+	freeaddrinfo(result);
+
+	return err;
+}
+
+#define RANDOM_LEN 10
+#define CLIENT_ID_LEN sizeof(CONFIG_BOARD) + 1 + RANDOM_LEN
+
+/* Function to get the client id */
+static const uint8_t* client_id_get(void)
+{
+	static uint8_t client_id[MAX(sizeof(CONFIG_MQTT_CLIENT_ID),
+				     CLIENT_ID_LEN)];
+
+	if (strlen(CONFIG_MQTT_CLIENT_ID) > 0) {
+		snprintf(client_id, sizeof(client_id), "%s",
+			 CONFIG_MQTT_CLIENT_ID);
+		goto exit;
+	}
+
+	char hw_id_buf[HW_ID_LEN] = {0};
+
+	int err = hw_id_get(hw_id_buf, ARRAY_SIZE(hw_id_buf));
+
+	if (!err) {
+		snprintf(client_id, sizeof(client_id), "nrf-%s",
+			 hw_id_buf);
+		goto exit;
+	}
+
+	LOG_ERR("failed to retrieve HW ID, err: %d", err);
+
+	uint32_t id = sys_rand32_get();
+	snprintf(client_id, sizeof(client_id), "%s-%010u", CONFIG_BOARD, id);
+
+exit:
+	LOG_DBG("client_id = %s", (char *)client_id);
+
+	return client_id;
+}
+
+/**@brief Initialize the MQTT client structure
+ */
+static int client_init(struct mqtt_client *client)
+{
+	int err;
+
+	mqtt_client_init(client);
+
+	err = broker_init();
+	if (err) {
+		LOG_ERR("Failed to initialize broker connection");
+		return err;
+	}
+
+	/* MQTT client configuration */
+	client->broker = &broker;
+	client->evt_cb = mqtt_evt_handler;
+	client->client_id.utf8 = client_id_get();
+	client->client_id.size = strlen(client->client_id.utf8);
+	client->password = NULL;
+	client->user_name = NULL;
+	client->protocol_version = MQTT_VERSION_3_1_1;
+
+	/* MQTT buffers configuration */
+	client->rx_buf = rx_buffer;
+	client->rx_buf_size = sizeof(rx_buffer);
+	client->tx_buf = tx_buffer;
+	client->tx_buf_size = sizeof(tx_buffer);
+
+	/* MQTT transport configuration */
+#if defined(CONFIG_MQTT_LIB_TLS)
+	struct mqtt_sec_config *tls_cfg = &(client->transport).tls.config;
+	static sec_tag_t sec_tag_list[] = { CONFIG_MQTT_TLS_SEC_TAG };
+
+	LOG_INF("TLS enabled");
+	client->transport.type = MQTT_TRANSPORT_SECURE;
+
+	tls_cfg->peer_verify = CONFIG_MQTT_TLS_PEER_VERIFY;
+	tls_cfg->cipher_count = 0;
+	tls_cfg->cipher_list = NULL;
+	tls_cfg->sec_tag_count = ARRAY_SIZE(sec_tag_list);
+	tls_cfg->sec_tag_list = sec_tag_list;
+	tls_cfg->hostname = CONFIG_MQTT_BROKER_HOSTNAME;
+
+#if defined(CONFIG_NRF_MODEM_LIB)
+	tls_cfg->session_cache = IS_ENABLED(CONFIG_MQTT_TLS_SESSION_CACHING) ?
+					    TLS_SESSION_CACHE_ENABLED :
+					    TLS_SESSION_CACHE_DISABLED;
+#else
+	/* TLS session caching is not supported by the Zephyr network stack */
+	tls_cfg->session_cache = TLS_SESSION_CACHE_DISABLED;
+
+#endif
+
+#else
+	client->transport.type = MQTT_TRANSPORT_NON_SECURE;
+#endif
+
+	return err;
+}
+
+/**@brief Initialize the file descriptor structure used by poll.
+ */
+static int fds_init(struct mqtt_client *c)
+{
+	if (c->transport.type == MQTT_TRANSPORT_NON_SECURE) {
+		fds.fd = c->transport.tcp.sock;
+	} else {
+#if defined(CONFIG_MQTT_LIB_TLS)
+		fds.fd = c->transport.tls.sock;
+#else
+		return -ENOTSUP;
+#endif
+	}
+
+	fds.events = POLLIN;
+
+	return 0;
+}
+
+#if defined(CONFIG_DK_LIBRARY)
+static void button_handler(uint32_t button_states, uint32_t has_changed)
+{
+	if (has_changed & button_states &
+	    BIT(CONFIG_BUTTON_EVENT_BTN_NUM - 1)) {
+		int ret;
+
+		ret = data_publish(&client,
+				   MQTT_QOS_1_AT_LEAST_ONCE,
+				   CONFIG_BUTTON_EVENT_PUBLISH_MSG,
+				   sizeof(CONFIG_BUTTON_EVENT_PUBLISH_MSG)-1);
+		if (ret) {
+			LOG_ERR("Publish failed: %d", ret);
+		}
+	}
+}
+#endif
+
+static int shell_mqtt_publish(const struct shell *shell, size_t argc, char **argv)
+{
+	ARG_UNUSED(argc);
+	ARG_UNUSED(argv);
+
+	int ret;
+
+	ret = data_publish(&client,
+			   MQTT_QOS_1_AT_LEAST_ONCE,
+			   CONFIG_BUTTON_EVENT_PUBLISH_MSG,
+			   sizeof(CONFIG_BUTTON_EVENT_PUBLISH_MSG) - 1);
+	if (ret) {
+		LOG_ERR("Publish failed: %d", ret);
+	}
+
+	return ret;
+}
+
+SHELL_STATIC_SUBCMD_SET_CREATE(mqtt_sub,
+		SHELL_CMD(publish, NULL, "Publish data to configured publish topic",
+			shell_mqtt_publish),
+		SHELL_SUBCMD_SET_END /* Array terminated. */
+);
+SHELL_CMD_REGISTER(mqtt, &mqtt_sub, "MQTT operations", NULL);
+
+/**@brief Configures modem to provide LTE link. Blocks until link is
+ * successfully established.
+ */
+static int modem_configure(void)
+{
+#if defined(CONFIG_LTE_LINK_CONTROL)
+	/* Turn off LTE power saving features for a more responsive demo. Also,
+	 * request power saving features before network registration. Some
+	 * networks rejects timer updates after the device has registered to the
+	 * LTE network.
+	 */
+	LOG_INF("Disabling PSM and eDRX");
+	lte_lc_psm_req(false);
+	lte_lc_edrx_req(false);
+
+	if (IS_ENABLED(CONFIG_LTE_AUTO_INIT_AND_CONNECT)) {
+		/* Do nothing, modem is already turned on
+		 * and connected.
+		 */
+	} else {
+		int err;
+
+		LOG_INF("LTE Link Connecting...");
+		err = lte_lc_init_and_connect();
+		if (err) {
+			LOG_INF("Failed to establish LTE connection: %d", err);
+			return err;
+		}
+		LOG_INF("LTE Link Connected!");
+	}
+#endif /* defined(CONFIG_LTE_LINK_CONTROL) */
+
+	return 0;
+}
+
+void main(void)
+{
+	int err;
+	uint32_t connect_attempt = 0;
+
+	LOG_INF("The MQTT simple sample started");
+
+#if defined(CONFIG_MQTT_LIB_TLS)
+	err = certificates_provision();
+	if (err != 0) {
+		LOG_ERR("Failed to provision certificates");
+		return;
+	}
+#endif /* defined(CONFIG_MQTT_LIB_TLS) */
+
+	do {
+		err = modem_configure();
+		if (err) {
+			LOG_INF("Retrying in %d seconds",
+				CONFIG_LTE_CONNECT_RETRY_DELAY_S);
+			k_sleep(K_SECONDS(CONFIG_LTE_CONNECT_RETRY_DELAY_S));
+		}
+	} while (err);
+
+	err = client_init(&client);
+	if (err != 0) {
+		LOG_ERR("client_init: %d", err);
+		return;
+	}
+
+#if defined(CONFIG_DK_LIBRARY)
+	dk_buttons_init(button_handler);
+#endif
+
+do_connect:
+	if (connect_attempt++ > 0) {
+		LOG_INF("Reconnecting in %d seconds...",
+			CONFIG_MQTT_RECONNECT_DELAY_S);
+		k_sleep(K_SECONDS(CONFIG_MQTT_RECONNECT_DELAY_S));
+	}
+	err = mqtt_connect(&client);
+	if (err != 0) {
+		LOG_ERR("mqtt_connect %d", err);
+		goto do_connect;
+	}
+
+	err = fds_init(&client);
+	if (err != 0) {
+		LOG_ERR("fds_init: %d", err);
+		return;
+	}
+
+	while (1) {
+		err = poll(&fds, 1, mqtt_keepalive_time_left(&client));
+		if (err < 0) {
+			LOG_ERR("poll: %d", errno);
+			break;
+		}
+
+		err = mqtt_live(&client);
+		if ((err != 0) && (err != -EAGAIN)) {
+			LOG_ERR("ERROR: mqtt_live: %d", err);
+			break;
+		}
+
+		if ((fds.revents & POLLIN) == POLLIN) {
+			err = mqtt_input(&client);
+			if (err != 0) {
+				LOG_ERR("mqtt_input: %d", err);
+				break;
+			}
+		}
+
+		if ((fds.revents & POLLERR) == POLLERR) {
+			LOG_ERR("POLLERR");
+			break;
+		}
+
+		if ((fds.revents & POLLNVAL) == POLLNVAL) {
+			LOG_ERR("POLLNVAL");
+			break;
+		}
+	}
+
+	LOG_INF("Disconnecting MQTT client...");
+
+	err = mqtt_disconnect(&client);
+	if (err) {
+		LOG_ERR("Could not disconnect MQTT client: %d", err);
+	}
+	goto do_connect;
+}
diff --git a/west.yml b/west.yml
new file mode 100644
index 0000000..7fd440b
--- /dev/null
+++ b/west.yml
@@ -0,0 +1,13 @@
+manifest:
+  remotes:
+    - name: ncs
+      url-base: https://github.com/nrfconnect
+  projects:
+    - name: sdk-nrf
+      remote: ncs
+      path: nrf
+      revision: v2.2.0
+      import: true
+      clone-depth: 1
+  self:
+    path: mqtt_simple