display error on startup, if previous version is older than 1.60

scm-webapp/src/main/java/sonia/scm/boot/BootstrapContextListener.java

@@ -63,6 +63,7 @@ import sonia.scm.util.IOUtil;
 import javax.servlet.ServletContext;
 import javax.servlet.ServletContextEvent;
 import javax.servlet.ServletContextListener;
+import javax.servlet.http.HttpServletResponse;
 import javax.xml.bind.DataBindingException;
 import javax.xml.bind.JAXB;
 import javax.xml.bind.annotation.XmlAccessType;
@@ -141,8 +142,11 @@ public class BootstrapContextListener implements ServletContextListener {
     Throwable startupError = SCMContext.getContext().getStartupError();
     if (startupError != null) {
       contextListener = SingleView.error(startupError);
+    } else if (Versions.isToOld()) {
+      contextListener = SingleView.view("/templates/to-old.mustache", HttpServletResponse.SC_CONFLICT);
     } else {
       createMigrationOrNormalContextListener();
+      Versions.writeNew();
     }
   }
 

scm-webapp/src/main/java/sonia/scm/boot/SingleView.java

@@ -37,6 +37,16 @@ final class SingleView {
     return new SingleViewContextListener(controller);
   }
 
+  static ServletContextListener view(String template, int sc) {
+    ViewController controller = new SimpleViewController(template, request -> {
+      Object model = ImmutableMap.of(
+        "contextPath", request.getContextPath()
+      );
+      return new View(sc, model);
+    });
+    return new SingleViewContextListener(controller);
+  }
+
   private static class SingleViewContextListener extends GuiceServletContextListener {
 
     private final ViewController controller;

scm-webapp/src/main/java/sonia/scm/boot/Versions.java

@@ -0,0 +1,77 @@
+package sonia.scm.boot;
+
+import com.google.common.annotations.VisibleForTesting;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import sonia.scm.SCMContext;
+import sonia.scm.SCMContextProvider;
+import sonia.scm.util.IOUtil;
+import sonia.scm.version.Version;
+
+import java.io.IOException;
+import java.nio.charset.StandardCharsets;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.nio.file.Paths;
+import java.util.Optional;
+
+class Versions {
+
+  private static final Logger LOG = LoggerFactory.getLogger(Versions.class);
+
+  private static final Version MIN_VERSION = Version.parse("1.60");
+
+  private final SCMContextProvider contextProvider;
+
+  @VisibleForTesting
+  Versions(SCMContextProvider contextProvider) {
+    this.contextProvider = contextProvider;
+  }
+
+  @VisibleForTesting
+  boolean isPreviousVersionToOld() {
+    return readVersion().map(v -> v.isOlder(MIN_VERSION)).orElse(false);
+  }
+
+  @VisibleForTesting
+  void writeNewVersion() {
+    Path config = contextProvider.resolve(Paths.get("config"));
+    IOUtil.mkdirs(config.toFile());
+
+    String version = contextProvider.getVersion();
+    LOG.debug("write new version {} to file", version);
+    Path versionFile = config.resolve("version.txt");
+    try {
+      Files.write(versionFile, version.getBytes());
+    } catch (IOException e) {
+      throw new IllegalStateException("failed to write version file", e);
+    }
+  }
+
+  private Optional<Version> readVersion() {
+    Path versionFile = contextProvider.resolve(Paths.get("config", "version.txt"));
+    if (versionFile.toFile().exists()) {
+      return Optional.of(readVersionFromFile(versionFile));
+    }
+    return Optional.empty();
+  }
+
+  private Version readVersionFromFile(Path versionFile) {
+    try {
+      String versionString = new String(Files.readAllBytes(versionFile), StandardCharsets.UTF_8).trim();
+      LOG.debug("read previous version {} from file", versionString);
+      return Version.parse(versionString);
+    } catch (IOException e) {
+      throw new IllegalStateException("failed to read version file", e);
+    }
+  }
+
+  static boolean isToOld() {
+    return new Versions(SCMContext.getContext()).isPreviousVersionToOld();
+  }
+
+  static void writeNew() {
+    new Versions(SCMContext.getContext()).writeNewVersion();
+  }
+
+}