Store add-on download count in the database.

The idea being that this could then also be included as a sheet in the multiplayer activity report, which would then be an easy way to view add-on downloads over time. This would of course not be especially useful until 1.18, since for 1.17 the database count would be starting at 0 even though existing add-ons would have a non-zero download count.

src/server/campaignd/server.cpp

@@ -1196,6 +1196,9 @@ void server::handle_request_campaign(const server::request& req)
 	if(req.cfg["increase_downloads"].to_bool(true) && !ignore_address_stats(req.addr)) {
 		addon["downloads"] = 1 + addon["downloads"].to_int();
 		mark_dirty(name);
+		if(user_handler_) {
+			user_handler_->db_update_addon_download_count(server_id_, name, to);
+		}
 	}
 }
 

src/server/common/dbconn.cpp

@@ -446,6 +446,19 @@ void dbconn::get_ips_for_user(const std::string& username, std::ostringstream* o
 	}
 }
 
+void dbconn::update_addon_download_count(const std::string& instance_version, const std::string& id, const std::string& version)
+{
+	try
+	{
+		modify(connection_, "UPDATE `"+db_addon_info_table_+"` SET DOWNLOAD_COUNT = DOWNLOAD_COUNT+1 WHERE INSTANCE_VERSION = ? AND ADDON_ID = ? AND VERSION = ?",
+			instance_version, id, version);
+	}
+	catch(const mariadb::exception::base& e)
+	{
+		log_sql_exception("Unable to update download count for add-on "+id+" with version "+version+".", e);
+	}
+}
+
 //
 // handle complex query results
 //

src/server/common/dbconn.hpp

@@ -174,6 +174,11 @@ class dbconn
 		 */
 		void get_ips_for_user(const std::string& username, std::ostringstream* out);
 
+		/**
+		 * @see forum_user_handler::db_update_addon_download_count().
+		 */
+		void update_addon_download_count(const std::string& instance_version, const std::string& id, const std::string& version);
+
 	private:
 		/**
 		 * The account used to connect to the database.

src/server/common/forum_user_handler.cpp

@@ -187,6 +187,10 @@ std::string fuh::get_user_email(const std::string& user) {
 	return conn_.get_user_string(db_users_table_, "user_email", user);
 }
 
+void fuh::db_update_addon_download_count(const std::string& instance_version, const std::string& id, const std::string& version) {
+	return conn_.update_addon_download_count(instance_version, id, version);
+}
+
 std::time_t fuh::get_lastlogin(const std::string& user) {
 	return std::time_t(conn_.get_user_int(db_extra_table_, "user_lastvisit", user));
 }

src/server/common/forum_user_handler.hpp

@@ -263,6 +263,15 @@ class fuh : public user_handler
 	 */
 	std::string get_user_email(const std::string& user);
 
+	/**
+	 * Increments the download count for this add-on for the specific version.
+	 * 
+	 * @param instance_version The version of campaignd the add-on was uploaded to.
+	 * @param id The add-on's ID (aka directory name).
+	 * @param version The version of the add-on being downloaded. May not be the most recent version.
+	 */
+	void db_update_addon_download_count(const std::string& instance_version, const std::string& id, const std::string& version);
+
 private:
 	/** An instance of the class responsible for executing the queries and handling the database connection. */
 	dbconn conn_;

src/server/common/user_handler.hpp

@@ -152,4 +152,5 @@ class user_handler
 	virtual void db_update_logout(unsigned long long login_id) = 0;
 	virtual void get_users_for_ip(const std::string& ip, std::ostringstream* out) = 0;
 	virtual void get_ips_for_user(const std::string& username, std::ostringstream* out) = 0;
+	virtual void db_update_addon_download_count(const std::string& instance_version, const std::string& id, const std::string& version) = 0;
 };

utils/mp-server/table_definitions.sql

@@ -134,6 +134,7 @@ create table game_content_info
 -- FORUM_AUTH: whether forum authentication is to be used when uploading
 -- UPLOADED_ON: when the addon was uploaded
 -- FEEDBACK_TOPIC: the forum topic ID where feedback for the addon can be posted, 0 if not set
+-- DOWNLOAD_COUNT: the number of times the add-on has been downloaded by players (does not count downloads from addons.wesnoth.org)
 create table addon_info
 (
     INSTANCE_VERSION VARCHAR(255) NOT NULL,
@@ -144,6 +145,7 @@ create table addon_info
     FORUM_AUTH       BIT(1) NOT NULL,
     UPLOADED_ON      TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
     FEEDBACK_TOPIC   INT UNSIGNED NOT NULL,
+    DOWNLOAD_COUNT   INT UNSIGNED NOT NULL DEFAULT 0,
     PRIMARY KEY (INSTANCE_VERSION, ADDON_ID, VERSION)
 ) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4;