mosquitto/plugins/persist-sqlite/restore.c

/*
Copyright (c) 2021 Roger Light <roger@atchoo.org>

All rights reserved. This program and the accompanying materials
are made available under the terms of the Eclipse Public License 2.0
and Eclipse Distribution License v1.0 which accompany this distribution.

The Eclipse Public License is available at
   https://www.eclipse.org/legal/epl-2.0/
and the Eclipse Distribution License is available at
  http://www.eclipse.org/org/documents/edl-v10.php.

SPDX-License-Identifier: EPL-2.0 OR BSD-3-Clause

Contributors:
   Roger Light - initial implementation and documentation.
*/

#include <stdlib.h>
#include <string.h>
#include <sqlite3.h>
#include <cjson/cJSON.h>

#include "mosquitto.h"
#include "mosquitto_broker.h"
#include "mqtt_protocol.h"
#include "persist_sqlite.h"

static mosquitto_property *json_to_properties(const char *json)
{
	mosquitto_property *properties = NULL;
	cJSON *array, *obj, *j_id, *j_value, *j_name;
	int propid, proptype;

	if(!json) return NULL;

	array = cJSON_Parse(json);
	if(!array) return NULL;
	if(!cJSON_IsArray(array)){
		cJSON_Delete(array);
		return NULL;
	}

	cJSON_ArrayForEach(obj, array){
		j_id = cJSON_GetObjectItem(obj, "identifier");
		j_name = cJSON_GetObjectItem(obj, "name");
		j_value = cJSON_GetObjectItem(obj, "value");

		if(!j_id || !cJSON_IsString(j_id) || !j_value){
			continue;
		}
		if(mosquitto_string_to_property_info(j_id->valuestring, &propid, &proptype)){
			continue;
		}
		switch(proptype){
			case MQTT_PROP_TYPE_BYTE:
				if(!cJSON_IsNumber(j_value)) continue;
				mosquitto_property_add_byte(&properties, propid, (uint8_t)j_value->valueint);
				break;
			case MQTT_PROP_TYPE_INT16:
				if(!cJSON_IsNumber(j_value)) continue;
				mosquitto_property_add_int16(&properties, propid, (uint16_t)j_value->valueint);
				break;
			case MQTT_PROP_TYPE_INT32:
				if(!cJSON_IsNumber(j_value)) continue;
				mosquitto_property_add_int32(&properties, propid, (uint32_t)j_value->valueint);
				break;
			case MQTT_PROP_TYPE_VARINT:
				if(!cJSON_IsNumber(j_value)) continue;
				mosquitto_property_add_varint(&properties, propid, (uint32_t)j_value->valueint);
				break;
			case MQTT_PROP_TYPE_BINARY:
				break;
			case MQTT_PROP_TYPE_STRING:
				if(!cJSON_IsString(j_value)) continue;
				mosquitto_property_add_string(&properties, propid, j_value->valuestring);
				break;
			case MQTT_PROP_TYPE_STRING_PAIR:
				if(!cJSON_IsString(j_value)) continue;
				if(!j_name || !cJSON_IsString(j_value)) continue;
				mosquitto_property_add_string_pair(&properties, propid, j_name->valuestring, j_value->valuestring);
				break;
		}
	}
	cJSON_Delete(array);

	return properties;
}


static int client_restore(struct mosquitto_sqlite *ms)
{
	sqlite3_stmt *stmt;
	int rc;
	struct mosquitto_evt_persist_client client;
	long count = 0, failed = 0;
	const char *str;

	memset(&client, 0, sizeof(client));

	rc = sqlite3_prepare_v2(ms->db,
			"SELECT client_id,username,will_delay_time,session_expiry_time,"
			"listener_port,max_packet_size,max_qos,"
			"retain_available,session_expiry_interval,will_delay_interval "
			"FROM clients",
			-1, &stmt, NULL);

	if(rc != SQLITE_OK){
		mosquitto_log_printf(MOSQ_LOG_ERR, "sqlite: Error restoring clients: %s", sqlite3_errstr(rc));
		return MOSQ_ERR_UNKNOWN;
	}


	while(sqlite3_step(stmt) == SQLITE_ROW){
		str = (const char *)sqlite3_column_text(stmt, 0);
		if(str){
			client.plugin_client_id = strdup(str);
		}
		str = (const char *)sqlite3_column_text(stmt, 1);
		if(str){
			client.plugin_username = strdup(str);
		}
		client.will_delay_time = (time_t)sqlite3_column_int64(stmt, 2);
		client.session_expiry_time = (time_t)sqlite3_column_int64(stmt, 3);
		client.listener_port = (uint16_t)sqlite3_column_int(stmt, 4);
		client.max_packet_size = (uint32_t)sqlite3_column_int(stmt, 5);
		client.max_qos = (uint8_t)sqlite3_column_int(stmt, 6);
		client.retain_available = (bool)sqlite3_column_int(stmt, 7);
		client.session_expiry_interval = (uint32_t)sqlite3_column_int(stmt, 8);
		client.will_delay_interval = (uint32_t)sqlite3_column_int(stmt, 9);

		rc = mosquitto_persist_client_add(&client);
		if(rc == MOSQ_ERR_SUCCESS){
			count++;
		}else{
			failed++;
		}
	}
	sqlite3_finalize(stmt);

	mosquitto_log_printf(MOSQ_LOG_INFO, "sqlite: Restored %ld clients (%ld failed)", count, failed);

	return rc;
}


static int subscription_restore(struct mosquitto_sqlite *ms)
{
	sqlite3_stmt *stmt;
	uint8_t subscription_options;
	uint32_t subscription_identifier;
	int rc;
	const char *client_id;
	const char *topic;
	long count = 0, failed = 0;

	rc = sqlite3_prepare_v2(ms->db,
			"SELECT client_id,topic,subscription_options,subscription_identifier "
			"FROM subscriptions",
			-1, &stmt, NULL);

	if(rc != SQLITE_OK){
		mosquitto_log_printf(MOSQ_LOG_ERR, "sqlite: Error restoring subscriptions: %s", sqlite3_errstr(rc));
		return MOSQ_ERR_UNKNOWN;
	}

	while(sqlite3_step(stmt) == SQLITE_ROW){
		client_id = (const char *)sqlite3_column_text(stmt, 0);
		topic = (const char *)sqlite3_column_text(stmt, 1);
		subscription_options = (uint8_t)sqlite3_column_int(stmt, 2);
		subscription_identifier = (uint32_t)sqlite3_column_int(stmt, 3);

		rc = mosquitto_subscription_add(client_id, topic, subscription_options, subscription_identifier);
		if(rc == MOSQ_ERR_SUCCESS){
			count++;
		}else{
			failed++;
		}
	}
	sqlite3_finalize(stmt);

	mosquitto_log_printf(MOSQ_LOG_INFO, "sqlite: Restored %ld subscriptions (%ld failed)", count, failed);

	return MOSQ_ERR_SUCCESS;
}


static int msg_restore(struct mosquitto_sqlite *ms)
{
	sqlite3_stmt *stmt;
	struct mosquitto_evt_persist_base_msg msg;
	int rc;
	long count = 0, failed = 0;
	const char *str;
	const void *payload;

	rc = sqlite3_prepare_v2(ms->db,
			"SELECT store_id, expiry_time, topic, payload, source_id, source_username, payloadlen, source_mid, source_port, qos, retain, properties "
			"FROM base_msgs",
			-1, &stmt, NULL);

	if(rc != SQLITE_OK){
		mosquitto_log_printf(MOSQ_LOG_ERR, "sqlite: Error restoring messages: %s", sqlite3_errstr(rc));
		return MOSQ_ERR_UNKNOWN;
	}

	while(sqlite3_step(stmt) == SQLITE_ROW){
		memset(&msg, 0, sizeof(msg));
		msg.store_id = (uint64_t)sqlite3_column_int64(stmt, 0);
		msg.expiry_time = (time_t)sqlite3_column_int64(stmt, 1);
		str = (const char *)sqlite3_column_text(stmt, 2);
		if(str){
			msg.plugin_topic = strdup(str);
			if(!msg.plugin_topic){
				failed++;
				continue;
			}
		}
		msg.source_id = (const char *)sqlite3_column_text(stmt, 4);
		msg.source_username = (const char *)sqlite3_column_text(stmt, 5);
		payload = (const void *)sqlite3_column_blob(stmt, 3);
		msg.payloadlen = (uint32_t)sqlite3_column_int(stmt, 6);
		if(payload && msg.payloadlen){
			msg.plugin_payload = malloc(msg.payloadlen+1);
			if(!msg.plugin_payload){
				free(msg.plugin_topic);
				failed++;
				continue;
			}
			memcpy(msg.plugin_payload, payload, msg.payloadlen);
			((uint8_t *)msg.plugin_payload)[msg.payloadlen] = 0;
		}

		msg.source_mid = (uint16_t)sqlite3_column_int(stmt, 7);
		msg.source_port = (uint16_t)sqlite3_column_int(stmt, 8);
		msg.qos = (uint8_t)sqlite3_column_int(stmt, 9);
		msg.retain = sqlite3_column_int(stmt, 10);
		msg.plugin_properties = json_to_properties((const char *)sqlite3_column_text(stmt, 11));

		rc = mosquitto_persist_base_msg_add(&msg);
		if(rc == MOSQ_ERR_SUCCESS){
			count++;
		}else{
			failed++;
		}
	}
	sqlite3_finalize(stmt);

	mosquitto_log_printf(MOSQ_LOG_INFO, "sqlite: Restored %ld messages (%ld failed)", count, failed);
	return MOSQ_ERR_SUCCESS;
}


static int client_msg_restore(struct mosquitto_sqlite *ms)
{
	sqlite3_stmt *stmt;
	struct mosquitto_evt_persist_client_msg msg;
	int rc;
	long count = 0, failed = 0;

	rc = sqlite3_prepare_v2(ms->db,
			"SELECT client_id, store_id, dup, direction, mid, qos, retain, state "
			"FROM client_msgs ORDER BY rowid",
			-1, &stmt, NULL);

	if(rc != SQLITE_OK){
		mosquitto_log_printf(MOSQ_LOG_ERR, "sqlite: Error restoring client messages: %s", sqlite3_errstr(rc));
		return MOSQ_ERR_UNKNOWN;
	}

	memset(&msg, 0, sizeof(msg));
	while(sqlite3_step(stmt) == SQLITE_ROW){
		msg.client_id = (const char *)sqlite3_column_text(stmt, 0);
		msg.store_id = (uint64_t)sqlite3_column_int64(stmt, 1);
		msg.dup = sqlite3_column_int(stmt, 2);
		msg.direction = (uint8_t)sqlite3_column_int(stmt, 3);
		msg.mid = (uint16_t)sqlite3_column_int(stmt, 4);
		msg.qos = (uint8_t)sqlite3_column_int(stmt, 5);
		msg.retain = sqlite3_column_int(stmt, 6);
		msg.state = (uint8_t)sqlite3_column_int(stmt, 7);

		rc = mosquitto_persist_client_msg_add(&msg);
		if(rc == MOSQ_ERR_SUCCESS){
			count++;
		}else{
			failed++;
		}
	}
	sqlite3_finalize(stmt);

	mosquitto_log_printf(MOSQ_LOG_INFO, "sqlite: Restored %ld client messages (%ld failed)", count, failed);
	return MOSQ_ERR_SUCCESS;
}


static int retain_restore(struct mosquitto_sqlite *ms)
{
	sqlite3_stmt *stmt;
	int rc;
	long count = 0, failed = 0;
	const char *topic;
	uint64_t store_id;

	rc = sqlite3_prepare_v2(ms->db,
			"SELECT topic, store_id "
			"FROM retains ORDER BY topic",
			-1, &stmt, NULL);

	if(rc != SQLITE_OK){
		mosquitto_log_printf(MOSQ_LOG_ERR, "sqlite: Error restoring retained messages: %s", sqlite3_errstr(rc));
		return MOSQ_ERR_UNKNOWN;
	}

	while(sqlite3_step(stmt) == SQLITE_ROW){
		topic = (const char *)sqlite3_column_text(stmt, 0);
		if(!topic){
			failed++;
			continue;
		}
		store_id = (uint64_t)sqlite3_column_int64(stmt, 1);

		rc = mosquitto_persist_retain_msg_set(topic, store_id);
		if(rc == MOSQ_ERR_SUCCESS){
			count++;
		}else{
			failed++;
		}
	}
	sqlite3_finalize(stmt);

	mosquitto_log_printf(MOSQ_LOG_INFO, "sqlite: Restored %ld retained messages (%ld failed)", count, failed);
	return MOSQ_ERR_SUCCESS;
}


int persist_sqlite__restore_cb(int event, void *event_data, void *userdata)
{
	struct mosquitto_sqlite *ms = userdata;
	UNUSED(event);
	UNUSED(event_data);

	if(msg_restore(ms)) return MOSQ_ERR_UNKNOWN;
	if(retain_restore(ms)) return MOSQ_ERR_UNKNOWN;
	if(client_restore(ms)) return MOSQ_ERR_UNKNOWN;
	if(subscription_restore(ms)) return MOSQ_ERR_UNKNOWN;
	if(client_msg_restore(ms)) return MOSQ_ERR_UNKNOWN;

	return 0;
}