first implementation of cal.db, that

- successfully connects to db - updated db sheme - succeeds in listing appointments Signed-off-by: Stephan Richter <s.richter@srsoftware.de>
2024-12-22 20:33:35 +01:00
parent edfe423621
commit e4b8bcb99a
12 changed files with 214 additions and 29 deletions
@@ -0,0 +1,36 @@
+/* © SRSoftware 2024 */
+package de.srsoftware.cal.db;
+
+import de.srsoftware.cal.api.Appointment;
+import java.sql.SQLException;
+import java.util.List;
+import java.util.Set;
+
+/**
+ * Interface for calendar database
+ */
+public interface Database {
+	/**
+	 * add an appointment to the database
+	 * @param appointment the appointment to store
+	 * @return the Database object
+	 */
+	public Database add(Appointment appointment);
+
+	/**
+	 * list appointments unfiltered
+	 * @param count the maximum number of appointments to return
+	 * @param offset the number of appointments to skip
+	 * @return the list of appointments fetched from the db
+	 */
+	public List<Appointment> list(Integer count, Integer offset) throws SQLException;
+
+	/**
+	 * list appointments
+	 * @param tags only list appointments which have matching tags
+	 * @param count the maximum number of appointments to return
+	 * @param offset the number of appointments to skip
+	 * @return the list of appointments fetched from the db
+	 */
+	public List<Appointment> listByTags(Set<String> tags, Integer count, Integer offset);
+}
@@ -0,0 +1,121 @@
+/* © SRSoftware 2024 */
+package de.srsoftware.cal.db;
+
+import static de.srsoftware.tools.Optionals.allEmpty;
+import static de.srsoftware.tools.Optionals.nullable;
+
+import de.srsoftware.cal.BaseAppointment;
+import de.srsoftware.cal.api.Appointment;
+import de.srsoftware.tools.Calc;
+import de.srsoftware.tools.jdbc.Query;
+import java.sql.Connection;
+import java.sql.DriverManager;
+import java.sql.SQLException;
+import java.sql.Timestamp;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Set;
+
+public class MariaDB implements Database {
+	private static final String SELECT_APPOINTMENTS	            = "SELECT * FROM appointments";
+	private static final String SELECT_APPOINTMENTS_WITH_HASHES = SELECT_APPOINTMENTS + " a LEFT JOIN appointment_hashes h ON a.aid = h.aid";
+	private static final String SELECT_VERSION	            = "SELECT value FROM config WHERE keyname = 'dbversion'";
+	private static final String CREATE_HASHES	            = "CREATE TABLE appointment_hashes (aid INT NOT NULL, hash VARCHAR(255) NOT NULL, UNIQUE(aid), UNIQUE(hash))";
+	private static final String INSERT_HASH	            = "INSERT INTO appointment_hashes (aid, hash) values (?, ?) ON DUPLICATE KEY UPDATE hash=hash;";
+	private static final String UPDATE_DB_VERSION	            = "UPDATE config SET value = ? WHERE keyname = 'dbversion'";
+	private static Connection   connection;
+
+	private MariaDB(Connection conn) throws SQLException {
+		connection = conn;
+		applyUpdates();
+	}
+
+	private void applyUpdates() throws SQLException {
+		var rs      = Query.of(SELECT_VERSION).execute(connection);
+		var version = 0;
+		if (rs.next()) {
+			version = rs.getInt("value");
+		}
+		rs.close();
+		switch (version) {
+			case 0:
+				createTables();
+			case 1:
+				update1();
+		}
+	}
+
+	private void update1() throws SQLException {
+		var list    = new ArrayList<Appointment>();
+		var results = Query.of(SELECT_APPOINTMENTS).execute(connection);
+		while (results.next()) {
+			var id	= results.getInt("aid");
+			var title	= results.getString("title");
+			var description = results.getString("description");
+			if (allEmpty(title, description)) continue;
+			var stamp    = results.getTimestamp("start");
+			var start    = nullable(stamp).map(Timestamp::toLocalDateTime).orElse(null);
+			var end      = nullable(results.getTimestamp("end")).map(Timestamp::toLocalDateTime).orElse(null);
+			var location = results.getString("location");
+			Calc  //
+			    .hash(start + "@" + location)
+			    .map(hash -> new BaseAppointment(id, title, description, start, end, location, hash))
+			    .ifPresent(list::add);
+		}
+		results.close();
+		connection.setAutoCommit(false);
+
+		Query.of(CREATE_HASHES).statement(connection).execute();
+		for (var appointment : list) {
+			var stmt = Query.of(INSERT_HASH).statement(connection);
+			stmt.setLong(1, appointment.id());
+			stmt.setString(2, appointment.hash());
+			stmt.execute();
+		}
+		connection.commit();
+		var stmt = Query.of(UPDATE_DB_VERSION).statement(connection);
+		stmt.setLong(1, 2);
+		stmt.execute();
+		connection.setAutoCommit(true);
+	}
+
+	private void createTables() {
+		throw new RuntimeException("%s.createTables() not implemented!");
+	}
+
+
+	@Override
+	public Database add(Appointment appointment) {
+		return null;
+	}
+
+	public static Database connect(String jdbc, String user, String pass) throws SQLException {
+		return new MariaDB(DriverManager.getConnection(jdbc, user, pass));
+	}
+
+
+	@Override
+	public List<Appointment> list(Integer count, Integer offset) throws SQLException {
+		var list    = new ArrayList<Appointment>();
+		var results = Query.of(SELECT_APPOINTMENTS_WITH_HASHES).execute(connection);
+		while (results.next()) {
+			var id	= results.getInt("aid");
+			var title	= results.getString("title");
+			var description = results.getString("description");
+			if (allEmpty(title, description)) continue;
+			var start    = results.getTimestamp("start").toLocalDateTime();
+			var end      = nullable(results.getTimestamp("end")).map(Timestamp::toLocalDateTime).orElse(null);
+			var location = results.getString("location");
+			var hash     = results.getString("hash");
+			if (hash == null) hash = Calc.hash(start + "@" + location).orElse(null);
+			list.add(new BaseAppointment(id, title, description, start, end, location, hash));
+		}
+		results.close();
+		return list;
+	}
+
+	@Override
+	public List<Appointment> listByTags(Set<String> tags, Integer count, Integer offset) {
+		return List.of();
+	}
+}