lightdb: rework golioth_lightdb_set() on top of coap_req

This commit is phasing out direct CoAP dependency and low-level CoAP handling requirement when using golioth_lightdb_set() API. Add new golioth_lightdb_set_cb() callback based API, which is really just a thin wrapper around golioth_coap_req_cb() API, but leaves user flexibility of calling it from other golioth callback (which are all executed from system_client thread) as well as from time-sensitive threads like system workqueue. Update samples/lightdb/set to new API. Provide examples for both synchronous golioth_lightdb_set() and asynchronous (callback based) golioth_lightdb_set_cb() API. Add LOG_DBG() statements before and after lightdb API calls, so that it makes it clear that main thread blocks on the synchronous API, while continuing execution with the callback-based API. Signed-off-by: Marcin Niestroj <m.niestroj@emb.dev>
golioth · Oct 7, 2022 · 10dc6f1 · 10dc6f1
1 parent 5796567
commit 10dc6f1
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Showing 5 changed files with 119 additions and 56 deletions.
diff --git a/include/net/golioth/lightdb.h b/include/net/golioth/lightdb.h
@@ -64,22 +64,46 @@ int golioth_lightdb_get(struct golioth_client *client, const uint8_t *path,
 			uint8_t *data, size_t *len);
 
 /**
- * @brief Set value to Golioth's LightDB
+ * @brief Set value to Golioth's LightDB (callback based)
  *
- * Set new value to LightDB.
+ * Asynchronously request to store new value to LightDB and let @p cb be invoked when such value is
+ * actually stored or some error condition happens.
  *
- * @param client Client instance
- * @param path LightDB resource path
- * @param format Format of payload
- * @param data Payload data
- * @param data_len Payload length
+ * @warning Experimental API
+ *
+ * @param[in] client Client instance
+ * @param[in] path LightDB resource path
+ * @param[in] format Requested format of payload
+ * @param[in] data Pointer to data to be set
+ * @param[in] data_len Length of data to be set
+ * @param[in] cb Callback executed on response received, timeout or error
+ * @param[in] user_data User data passed to @p cb
+ *
+ * @retval 0 On success
+ * @retval <0 On failure
+ */
+int golioth_lightdb_set_cb(struct golioth_client *client, const uint8_t *path,
+			   enum golioth_content_format format,
+			   const uint8_t *data, size_t data_len,
+			   golioth_req_cb_t cb, void *user_data);
+
+/**
+ * @brief Set value to Golioth's LightDB (synchronously)
+ *
+ * Synchronously set new value to LightDB.
+ *
+ * @param[in] client Client instance
+ * @param[in] path LightDB resource path
+ * @param[in] format Format of payload
+ * @param[in] data Payload data
+ * @param[in] data_len Payload length
  *
  * @retval 0 On success
  * @retval <0 On failure
  */
 int golioth_lightdb_set(struct golioth_client *client, const uint8_t *path,
 			enum golioth_content_format format,
-			uint8_t *data, uint16_t data_len);
+			const uint8_t *data, size_t data_len);
 
 /**
  * @brief Delete value in Golioth's LightDB

diff --git a/net/golioth/lightdb.c b/net/golioth/lightdb.c
@@ -110,36 +110,25 @@ int golioth_lightdb_get(struct golioth_client *client, const uint8_t *path,
 	return 0;
 }
 
+int golioth_lightdb_set_cb(struct golioth_client *client, const uint8_t *path,
+			   enum golioth_content_format format,
+			   const uint8_t *data, size_t data_len,
+			   golioth_req_cb_t cb, void *user_data)
+{
+	return golioth_coap_req_lightdb_cb(client, COAP_METHOD_POST, path, format,
+					   data, data_len,
+					   cb, user_data,
+					   GOLIOTH_COAP_REQ_NO_RESP_BODY);
+}
+
 int golioth_lightdb_set(struct golioth_client *client, const uint8_t *path,
 			enum golioth_content_format format,
-			uint8_t *data, uint16_t data_len)
+			const uint8_t *data, size_t data_len)
 {
-	struct coap_packet packet;
-	uint8_t buffer[GOLIOTH_COAP_MAX_NON_PAYLOAD_LEN];
-	int err;
-
-	err = coap_packet_init(&packet, buffer, sizeof(buffer),
-			       COAP_VERSION_1, COAP_TYPE_CON,
-			       COAP_TOKEN_MAX_LEN, coap_next_token(),
-			       COAP_METHOD_POST, coap_next_id());
-	if (err) {
-		return err;
-	}
-
-	err = coap_packet_append_uri_path_from_stringz(&packet, path);
-	if (err) {
-		LOG_ERR("Unable add uri path to packet");
-		return err;
-	}
-
-	err = coap_append_option_int(&packet, COAP_OPTION_CONTENT_FORMAT,
-				     format);
-	if (err) {
-		LOG_ERR("Unable add content format to packet");
-		return err;
-	}
-
-	return golioth_send_coap_payload(client, &packet, data, data_len);
+	return golioth_coap_req_lightdb_sync(client, COAP_METHOD_POST, path, format,
+					     data, data_len,
+					     NULL, NULL,
+					     GOLIOTH_COAP_REQ_NO_RESP_BODY);
 }
 
 static int golioth_coap_observe_init(struct coap_packet *packet,

diff --git a/samples/lightdb/set/README.rst b/samples/lightdb/set/README.rst
@@ -145,16 +145,28 @@ This is the output from the serial console:
 
 .. code-block:: console
 
-   [00:00:04.033,000] <inf> esp_event: WIFI_EVENT_STA_DISCONNECTED
-   [00:00:04.186,000] <inf> esp_event: WIFI_EVENT_STA_CONNECTED
-   [00:00:08.102,000] <inf> net_dhcpv4: Received: 192.168.0.180
-   [00:00:08.102,000] <inf> net_config: IPv4 address: 192.168.0.180
-   [00:00:08.102,000] <inf> net_config: Lease time: 7200 seconds
-   [00:00:08.102,000] <inf> net_config: Subnet: 255.255.255.0
-   [00:00:08.102,000] <inf> net_config: Router: 192.168.0.1
-   [00:00:08.102,000] <dbg> golioth_lightdb.main: Start LightDB set sample
-   [00:00:08.102,000] <inf> golioth_system: Starting connect
-   [00:00:08.103,000] <inf> golioth_system: Client connected!
+   [00:00:00.000,000] <inf> golioth_system: Initializing
+   [00:00:00.000,000] <inf> net_config: Initializing network
+   [00:00:00.000,000] <inf> net_config: IPv4 address: 192.0.2.1
+   [00:00:00.000,000] <dbg> golioth_lightdb: main: Start LightDB set sample
+   [00:00:00.010,000] <inf> golioth_system: Starting connect
+   [00:00:00.030,000] <dbg> golioth_lightdb: main: Setting counter to 0
+   [00:00:00.030,000] <dbg> golioth_lightdb: main: Before request (async)
+   [00:00:00.030,000] <dbg> golioth_lightdb: main: After request (async)
+   [00:00:00.030,000] <inf> golioth_system: Client connected!
+   [00:00:00.030,000] <dbg> golioth_lightdb: counter_set_handler: Counter successfully set
+   [00:00:05.040,000] <dbg> golioth_lightdb: main: Setting counter to 1
+   [00:00:05.040,000] <dbg> golioth_lightdb: main: Before request (sync)
+   [00:00:05.040,000] <dbg> golioth_lightdb: counter_set_sync: Counter successfully set
+   [00:00:05.040,000] <dbg> golioth_lightdb: main: After request (sync)
+   [00:00:10.050,000] <dbg> golioth_lightdb: main: Setting counter to 2
+   [00:00:10.050,000] <dbg> golioth_lightdb: main: Before request (async)
+   [00:00:10.050,000] <dbg> golioth_lightdb: main: After request (async)
+   [00:00:10.050,000] <dbg> golioth_lightdb: counter_set_handler: Counter successfully set
+   [00:00:15.060,000] <dbg> golioth_lightdb: main: Setting counter to 3
+   [00:00:15.060,000] <dbg> golioth_lightdb: main: Before request (sync)
+   [00:00:15.060,000] <dbg> golioth_lightdb: counter_set_sync: Counter successfully set
+   [00:00:15.060,000] <dbg> golioth_lightdb: main: After request (sync)
 
 Monitor counter value
 =====================

diff --git a/samples/lightdb/set/prj.conf b/samples/lightdb/set/prj.conf
@@ -22,4 +22,4 @@ CONFIG_MAIN_STACK_SIZE=4096
 CONFIG_GOLIOTH=y
 CONFIG_GOLIOTH_SYSTEM_CLIENT=y
 
-CONFIG_MINIMAL_LIBC_MALLOC_ARENA_SIZE=256
+CONFIG_MINIMAL_LIBC_MALLOC_ARENA_SIZE=2048
diff --git a/samples/lightdb/set/src/main.c b/samples/lightdb/set/src/main.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2021 Golioth, Inc.
+ * Copyright (c) 2021-2022 Golioth, Inc.
  *
  * SPDX-License-Identifier: Apache-2.0
  */
@@ -9,7 +9,6 @@ LOG_MODULE_REGISTER(golioth_lightdb, LOG_LEVEL_DBG);
 
 #include <net/golioth/system_client.h>
 #include <samples/common/net_connect.h>
-#include <zephyr/net/coap.h>
 
 #include <stdlib.h>
 
@@ -22,23 +21,51 @@ static void golioth_on_connect(struct golioth_client *client)
 	k_sem_give(&connected);
 }
 
-/*
- * This function stores `counter` in lightdb at `/counter`.
- */
-static void counter_set(int counter)
+static int counter_set_handler(struct golioth_req_rsp *rsp)
+{
+	if (rsp->err) {
+		LOG_WRN("Failed to set counter: %d", rsp->err);
+		return rsp->err;
+	}
+
+	LOG_DBG("Counter successfully set");
+
+	return 0;
+}
+
+static void counter_set_async(int counter)
 {
 	char sbuf[sizeof("4294967295")];
 	int err;
 
 	snprintk(sbuf, sizeof(sbuf) - 1, "%d", counter);
 
-	err = golioth_lightdb_set(client,
-				  GOLIOTH_LIGHTDB_PATH("counter"),
+	err = golioth_lightdb_set_cb(client, "counter",
+				     GOLIOTH_CONTENT_FORMAT_APP_JSON,
+				     sbuf, strlen(sbuf),
+				     counter_set_handler, NULL);
+	if (err) {
+		LOG_WRN("Failed to set counter: %d", err);
+		return;
+	}
+}
+
+static void counter_set_sync(int counter)
+{
+	char sbuf[sizeof("4294967295")];
+	int err;
+
+	snprintk(sbuf, sizeof(sbuf) - 1, "%d", counter);
+
+	err = golioth_lightdb_set(client, "counter",
 				  GOLIOTH_CONTENT_FORMAT_APP_JSON,
 				  sbuf, strlen(sbuf));
 	if (err) {
-		LOG_WRN("Failed to update counter: %d", err);
+		LOG_WRN("Failed to set counter: %d", err);
+		return;
 	}
+
+	LOG_DBG("Counter successfully set");
 }
 
 void main(void)
@@ -58,10 +85,21 @@ void main(void)
 
 	while (true) {
 		LOG_DBG("Setting counter to %d", counter);
-		counter_set(counter);
+
+		LOG_DBG("Before request (async)");
+		counter_set_async(counter);
+		LOG_DBG("After request (async)");
 
 		counter++;
+		k_sleep(K_SECONDS(5));
+
+		LOG_DBG("Setting counter to %d", counter);
+
+		LOG_DBG("Before request (sync)");
+		counter_set_sync(counter);
+		LOG_DBG("After request (sync)");
 
+		counter++;
 		k_sleep(K_SECONDS(5));
 	}
 }