app: Add CoAP client

Add CoAP client to the Serial Modem application.

Jira: SM-225

Signed-off-by: Juha Ylinen <juha.ylinen@nordicsemi.no>

Author: juhaylinen

app/CMakeLists.txt

@@ -29,6 +29,7 @@ target_sources_ifdef(CONFIG_SM_CMUX app PRIVATE src/sm_cmux.c)
 target_sources_ifdef(CONFIG_SM_GNSS app PRIVATE src/sm_at_gnss.c)
 target_sources_ifdef(CONFIG_SM_NRF_CLOUD app PRIVATE src/sm_at_nrfcloud.c)
 target_sources_ifdef(CONFIG_SM_MQTTC app PRIVATE src/sm_at_mqtt.c)
+target_sources_ifdef(CONFIG_SM_COAP app PRIVATE src/sm_at_coap.c)
 target_sources_ifdef(CONFIG_SM_HTTPC app PRIVATE src/sm_at_httpc.c)
 target_sources_ifdef(CONFIG_SM_MODEM_TRACE_BACKEND_CMUX app PRIVATE src/sm_trace_backend_cmux.c)
 target_sources_ifdef(CONFIG_SM_MODEM_TRACE_BACKEND_UART app PRIVATE src/sm_trace_backend_uart.c)

app/Kconfig

@@ -266,6 +266,15 @@ config SM_NRF_CLOUD_LOCATION
 	  Enable the nRF Cloud Location service for cloud-assisted geolocation.
 	  Supports cellular and Wi-Fi positioning.
 
+config SM_COAP
+	bool "CoAP client support"
+	default y
+	select COAP
+	select COAP_CLIENT
+	select EXPERIMENTAL
+	help
+	  Enable CoAP client AT commands for making CoAP requests.
+
 config SM_MQTTC
 	bool "MQTT client support"
 	default y

app/prj.conf

@@ -115,6 +115,8 @@ CONFIG_COAP_CLIENT_BLOCK_SIZE=1024
 CONFIG_COAP_CLIENT_THREAD_PRIORITY=0
 CONFIG_COAP_EXTENDED_OPTIONS_LEN_VALUE=96
 CONFIG_COAP_CLIENT_STACK_SIZE=2048
+# nrf_provisioning uses 1 instance; AT#XCOAPCREQ uses a second; allow both
+CONFIG_COAP_CLIENT_MAX_INSTANCES=3
 
 # UUID and JWT
 CONFIG_MODEM_JWT=y
@@ -155,3 +157,8 @@ CONFIG_SM_EXTERNAL_XTAL=n
 # For using external GNSS antenna
 #CONFIG_MODEM_ANTENNA=y
 #CONFIG_MODEM_ANTENNA_GNSS_EXTERNAL=y
+
+CONFIG_SM_AUTO_CONNECT=y
+
+#CONFIG_NET_LOG=y
+#CONFIG_COAP_LOG_LEVEL_INF=y