Implement swap/restore in SqliteDBStore

services/git-bridge/src/main/java/uk/ac/ic/wlgitbridge/bridge/db/sqlite/SqliteDBStore.java

@@ -104,6 +104,21 @@ public class SqliteDBStore implements DBStore {
         update(new SetProjectLastAccessedTime(projectName, lastAccessed));
     }
 
+    @Override
+    public void swap(String projectName, String compressionMethod) {
+      update(new UpdateSwap(projectName, compressionMethod));
+    }
+
+    @Override
+    public void restore(String projectName) {
+      update(new UpdateRestore(projectName));
+    }
+
+    @Override
+    public String getSwapCompression(String projectName) {
+        return query(new GetSwapCompression(projectName));
+    }
+
     private Connection openConnectionTo(File dbFile) {
         File parentDir = dbFile.getParentFile();
         if (!parentDir.exists() && !parentDir.mkdirs()) {
@@ -127,20 +142,27 @@ public class SqliteDBStore implements DBStore {
     }
 
     private void createTables() {
-        try {
-            doUpdate(new ProjectsAddLastAccessed());
-        } catch (SQLException ignore) {
-            /* We need to eat exceptions from here */
-        }
+        /* Migrations */
+        /* We need to eat exceptions from here */
+        try { doUpdate(new ProjectsAddLastAccessed()); } catch (SQLException ignore) {}
+        try { doUpdate(new ProjectsAddSwapTime()); } catch (SQLException ignore) {}
+        try { doUpdate(new ProjectsAddRestoreTime()); } catch (SQLException ignore) {}
+        try { doUpdate(new ProjectsAddSwapCompression()); } catch (SQLException ignore) {}
+
+        /* Create tables (if they don't exist) */
         Stream.of(
                 new CreateProjectsTableSQLUpdate(),
                 new CreateProjectsIndexLastAccessed(),
                 new CreateURLIndexStoreSQLUpdate(),
                 new CreateIndexURLIndexStore()
         ).forEach(this::update);
+
         /* In the case of needing to change the schema, we need to check that
-           ProjectsAddLastAccessed didn't just fail */
+           migrations didn't just fail */
         Preconditions.checkState(query(new LastAccessedColumnExists()));
+        Preconditions.checkState(query(new SwapTimeColumnExists()));
+        Preconditions.checkState(query(new RestoreTimeColumnExists()));
+        Preconditions.checkState(query(new SwapCompressionColumnExists()));
     }
 
     private void update(SQLUpdate update) {

services/git-bridge/src/main/java/uk/ac/ic/wlgitbridge/bridge/db/sqlite/query/GetSwapCompression.java

@@ -0,0 +1,39 @@
+package uk.ac.ic.wlgitbridge.bridge.db.sqlite.query;
+
+import uk.ac.ic.wlgitbridge.bridge.db.sqlite.SQLQuery;
+
+import java.sql.PreparedStatement;
+import java.sql.ResultSet;
+import java.sql.SQLException;
+
+public class GetSwapCompression implements SQLQuery<String> {
+  private static final String GET_SWAP_COMPRESSION =
+    "SELECT `swap_compression` FROM `projects` WHERE `name` = ?";
+
+  private final String projectName;
+
+  public GetSwapCompression(String projectName) {
+    this.projectName = projectName;
+  }
+
+  @Override
+  public String processResultSet(ResultSet resultSet) throws SQLException {
+    String compression = null;
+    while (resultSet.next()) {
+      compression = resultSet.getString("swap_compression");
+    }
+    return compression;
+  }
+
+  @Override
+  public String getSQL() {
+    return GET_SWAP_COMPRESSION;
+  }
+
+  @Override
+  public void addParametersToStatement(
+    PreparedStatement statement
+  ) throws SQLException {
+    statement.setString(1, projectName);
+  }
+}

services/git-bridge/src/main/java/uk/ac/ic/wlgitbridge/bridge/db/sqlite/query/RestoreTimeColumnExists.java

@@ -0,0 +1,26 @@
+package uk.ac.ic.wlgitbridge.bridge.db.sqlite.query;
+
+import uk.ac.ic.wlgitbridge.bridge.db.sqlite.SQLQuery;
+
+import java.sql.ResultSet;
+import java.sql.SQLException;
+
+public class RestoreTimeColumnExists implements SQLQuery<Boolean> {
+    private static final String RESTORE_TIME_COLUMN_EXISTS =
+            "PRAGMA table_info(`projects`)";
+
+    @Override
+    public String getSQL() {
+        return RESTORE_TIME_COLUMN_EXISTS;
+    }
+
+    @Override
+    public Boolean processResultSet(ResultSet resultSet) throws SQLException {
+        while (resultSet.next()) {
+            if (resultSet.getString(2).equals("restore_time")) {
+                return true;
+            }
+        }
+        return false;
+    }
+}

services/git-bridge/src/main/java/uk/ac/ic/wlgitbridge/bridge/db/sqlite/query/SwapCompressionColumnExists.java

@@ -0,0 +1,27 @@
+package uk.ac.ic.wlgitbridge.bridge.db.sqlite.query;
+
+import uk.ac.ic.wlgitbridge.bridge.db.sqlite.SQLQuery;
+
+import java.sql.ResultSet;
+import java.sql.SQLException;
+
+public class SwapCompressionColumnExists implements SQLQuery<Boolean> {
+    private static final String SWAP_COMPRESSION_COLUMN_EXISTS =
+            "PRAGMA table_info(`projects`)";
+
+    @Override
+    public String getSQL() {
+        return SWAP_COMPRESSION_COLUMN_EXISTS;
+    }
+
+    @Override
+    public Boolean processResultSet(ResultSet resultSet) throws SQLException {
+        while (resultSet.next()) {
+            if (resultSet.getString(2).equals("swap_compression")) {
+                return true;
+            }
+        }
+        return false;
+    }
+
+}

services/git-bridge/src/main/java/uk/ac/ic/wlgitbridge/bridge/db/sqlite/query/SwapTimeColumnExists.java

@@ -0,0 +1,27 @@
+package uk.ac.ic.wlgitbridge.bridge.db.sqlite.query;
+
+import uk.ac.ic.wlgitbridge.bridge.db.sqlite.SQLQuery;
+
+import java.sql.ResultSet;
+import java.sql.SQLException;
+
+public class SwapTimeColumnExists implements SQLQuery<Boolean> {
+    private static final String SWAP_TIME_COLUMN_EXISTS =
+            "PRAGMA table_info(`projects`)";
+
+    @Override
+    public String getSQL() {
+        return SWAP_TIME_COLUMN_EXISTS;
+    }
+
+    @Override
+    public Boolean processResultSet(ResultSet resultSet) throws SQLException {
+        while (resultSet.next()) {
+            if (resultSet.getString(2).equals("swap_time")) {
+                return true;
+            }
+        }
+        return false;
+    }
+
+}

services/git-bridge/src/main/java/uk/ac/ic/wlgitbridge/bridge/db/sqlite/update/alter/ProjectsAddRestoreTime.java

@@ -0,0 +1,14 @@
+package uk.ac.ic.wlgitbridge.bridge.db.sqlite.update.alter;
+
+import uk.ac.ic.wlgitbridge.bridge.db.sqlite.SQLUpdate;
+
+public class ProjectsAddRestoreTime implements SQLUpdate {
+  private static final String PROJECTS_ADD_RESTORE_TIME =
+    "ALTER TABLE `projects`\n" +
+      "ADD COLUMN `restore_time` DATETIME NULL;\n";
+
+  @Override
+  public String getSQL() {
+    return PROJECTS_ADD_RESTORE_TIME;
+  }
+}

services/git-bridge/src/main/java/uk/ac/ic/wlgitbridge/bridge/db/sqlite/update/alter/ProjectsAddSwapCompression.java

@@ -0,0 +1,14 @@
+package uk.ac.ic.wlgitbridge.bridge.db.sqlite.update.alter;
+
+import uk.ac.ic.wlgitbridge.bridge.db.sqlite.SQLUpdate;
+
+public class ProjectsAddSwapCompression implements SQLUpdate {
+  private static final String PROJECTS_ADD_SWAP_COMPRESSION =
+    "ALTER TABLE `projects`\n" +
+      "ADD COLUMN `swap_compression` VARCHAR NULL;\n";
+
+  @Override
+  public String getSQL() {
+    return PROJECTS_ADD_SWAP_COMPRESSION;
+  }
+}

services/git-bridge/src/main/java/uk/ac/ic/wlgitbridge/bridge/db/sqlite/update/alter/ProjectsAddSwapTime.java

@@ -0,0 +1,15 @@
+package uk.ac.ic.wlgitbridge.bridge.db.sqlite.update.alter;
+
+import uk.ac.ic.wlgitbridge.bridge.db.sqlite.SQLUpdate;
+
+public class ProjectsAddSwapTime implements SQLUpdate {
+  private static final String PROJECTS_ADD_SWAP_TIME =
+    "ALTER TABLE `projects`\n" +
+      "ADD COLUMN `swap_time` DATETIME NULL;\n";
+
+  @Override
+  public String getSQL() {
+    return PROJECTS_ADD_SWAP_TIME;
+  }
+
+}

services/git-bridge/src/main/java/uk/ac/ic/wlgitbridge/bridge/db/sqlite/update/create/CreateProjectsTableSQLUpdate.java

@@ -12,6 +12,9 @@ public class CreateProjectsTableSQLUpdate implements SQLUpdate {
             "    `name` VARCHAR NOT NULL DEFAULT '',\n" +
             "    `version_id` INT NOT NULL DEFAULT 0,\n" +
             "    `last_accessed` DATETIME NULL DEFAULT 0,\n" +
+            "    `swap_time` DATETIME NULL,\n" +
+            "    `restore_time` DATETIME NULL,\n" +
+            "    `swap_compression` VARCHAR NULL,\n" +
             "    PRIMARY KEY (`name`)\n" +
             ")";
 

services/git-bridge/src/main/java/uk/ac/ic/wlgitbridge/bridge/db/sqlite/update/insert/UpdateRestore.java

@@ -0,0 +1,40 @@
+package uk.ac.ic.wlgitbridge.bridge.db.sqlite.update.insert;
+
+import uk.ac.ic.wlgitbridge.bridge.db.sqlite.SQLUpdate;
+
+import java.sql.PreparedStatement;
+import java.sql.SQLException;
+import java.sql.Timestamp;
+import java.time.LocalDateTime;
+
+public class UpdateRestore implements SQLUpdate {
+  private static final String UPDATE_RESTORE =
+    "UPDATE `projects`\n" +
+      "SET `last_accessed` = ?,\n" +
+      "    `swap_time` = NULL,\n" +
+      "    `restore_time` = ?,\n" +
+      "    `swap_compression` = NULL\n" +
+      "WHERE `name` = ?;\n";
+
+  private final String projectName;
+  private final Timestamp now;
+
+  public UpdateRestore(String projectName) {
+    this.projectName = projectName;
+    this.now = Timestamp.valueOf(LocalDateTime.now());
+  }
+
+  @Override
+  public String getSQL() {
+    return UPDATE_RESTORE;
+  }
+
+  @Override
+  public void addParametersToStatement(
+    PreparedStatement statement
+  ) throws SQLException {
+    statement.setTimestamp(1, now);
+    statement.setTimestamp(2, now);
+    statement.setString(3, projectName);
+  }
+}

services/git-bridge/src/main/java/uk/ac/ic/wlgitbridge/bridge/db/sqlite/update/insert/UpdateSwap.java

@@ -0,0 +1,42 @@
+package uk.ac.ic.wlgitbridge.bridge.db.sqlite.update.insert;
+
+import uk.ac.ic.wlgitbridge.bridge.db.sqlite.SQLUpdate;
+
+import java.sql.PreparedStatement;
+import java.sql.SQLException;
+import java.sql.Timestamp;
+import java.time.LocalDateTime;
+
+public class UpdateSwap implements SQLUpdate {
+  private static final String UPDATE_SWAP =
+    "UPDATE `projects`\n" +
+      "SET `last_accessed` = NULL,\n" +
+      "    `swap_time` = ?,\n" +
+      "    `restore_time` = NULL,\n" +
+      "    `swap_compression` = ?\n" +
+      "WHERE `name` = ?;\n";
+
+  private final String projectName;
+  private final String compression;
+  private final Timestamp now;
+
+  public UpdateSwap(String projectName, String compression) {
+    this.projectName = projectName;
+    this.compression = compression;
+    this.now = Timestamp.valueOf(LocalDateTime.now());
+  }
+
+  @Override
+  public String getSQL() {
+    return UPDATE_SWAP;
+  }
+
+  @Override
+  public void addParametersToStatement(
+    PreparedStatement statement
+  ) throws SQLException {
+    statement.setTimestamp(1, now);
+    statement.setString(2, compression);
+    statement.setString(3, projectName);
+  }
+}