Extract common functionality

scm-plugins/scm-git-plugin/src/main/java/sonia/scm/web/lfs/ExpiringAction.java

@@ -0,0 +1,19 @@
+package sonia.scm.web.lfs;
+
+import org.eclipse.jgit.lfs.server.Response;
+import sonia.scm.security.AccessToken;
+
+import java.text.SimpleDateFormat;
+import java.util.Collections;
+
+@SuppressWarnings({"squid:S00116"})
+// This class is used for json serialization, only
+class ExpiringAction extends Response.Action {
+  public final String expires_at;
+
+  ExpiringAction(String href, AccessToken accessToken) {
+    this.expires_at = new SimpleDateFormat("yyyy-MM-dd'T'HH:MM:ss'Z'").format(accessToken.getExpiration());
+    this.href = href;
+    this.header = Collections.singletonMap("Authorization", "Bearer " + accessToken.compact());
+  }
+}

scm-plugins/scm-git-plugin/src/main/java/sonia/scm/web/lfs/LFSAuthCommand.java

@@ -0,0 +1,74 @@
+package sonia.scm.web.lfs;
+
+import com.fasterxml.jackson.databind.ObjectMapper;
+import sonia.scm.config.ScmConfiguration;
+import sonia.scm.plugin.Extension;
+import sonia.scm.protocolcommand.CommandInterpreter;
+import sonia.scm.protocolcommand.CommandInterpreterFactory;
+import sonia.scm.protocolcommand.RepositoryContext;
+import sonia.scm.protocolcommand.RepositoryContextResolver;
+import sonia.scm.protocolcommand.ScmCommandProtocol;
+import sonia.scm.protocolcommand.git.GitRepositoryContextResolver;
+import sonia.scm.repository.Repository;
+import sonia.scm.security.AccessToken;
+import sonia.scm.security.AccessTokenBuilderFactory;
+
+import javax.inject.Inject;
+import java.io.ByteArrayOutputStream;
+import java.util.Optional;
+import java.util.concurrent.TimeUnit;
+
+import static java.lang.String.format;
+
+@Extension
+public class LFSAuthCommand implements CommandInterpreterFactory {
+
+  private final AccessTokenBuilderFactory tokenBuilderFactory;
+  private final GitRepositoryContextResolver gitRepositoryContextResolver;
+  private final ObjectMapper objectMapper;
+  private final String baseUrl;
+
+  @Inject
+  public LFSAuthCommand(AccessTokenBuilderFactory tokenBuilderFactory, GitRepositoryContextResolver gitRepositoryContextResolver, ScmConfiguration configuration) {
+    this.tokenBuilderFactory = tokenBuilderFactory;
+    this.gitRepositoryContextResolver = gitRepositoryContextResolver;
+
+    objectMapper = new ObjectMapper();
+    baseUrl = configuration.getBaseUrl();
+  }
+
+  @Override
+  public Optional<CommandInterpreter> canHandle(String command) {
+    return command.startsWith("git-lfs-authenticate") ? Optional.of(new CommandInterpreter() {
+      @Override
+      public String[] getParsedArgs() {
+        // we are interested only in the 'repo' argument, so we discard the rest
+        return new String[] {command.split("\\s+")[1]};
+      }
+
+      @Override
+      public ScmCommandProtocol getProtocolHandler() {
+        return (context, repositoryContext) -> {
+          ExpiringAction response = createResponse(repositoryContext);
+          ByteArrayOutputStream buffer = new ByteArrayOutputStream();
+          objectMapper.writeValue(buffer, response);
+          context.getOutputStream().write(buffer.toString().getBytes());
+        };
+      }
+
+      private ExpiringAction createResponse(RepositoryContext repositoryContext) {
+        AccessToken accessToken = tokenBuilderFactory.create().expiresIn(5, TimeUnit.MINUTES).build();
+
+        Repository repository = repositoryContext.getRepository();
+        String url = format("%s/repo/%s/%s.git/info/lfs/", baseUrl, repository.getNamespace(), repository.getName());
+
+        return new ExpiringAction(url, accessToken);
+      }
+
+      @Override
+      public RepositoryContextResolver getRepositoryContextResolver() {
+        return gitRepositoryContextResolver;
+      }
+    }) : Optional.empty();
+  }
+}

scm-plugins/scm-git-plugin/src/main/java/sonia/scm/web/lfs/ScmBlobLfsRepository.java

@@ -12,11 +12,6 @@ import sonia.scm.store.Blob;
 import sonia.scm.store.BlobStore;
 
 import java.io.IOException;
-import java.sql.Date;
-import java.text.SimpleDateFormat;
-import java.time.Instant;
-import java.time.temporal.ChronoUnit;
-import java.util.HashMap;
 import java.util.concurrent.TimeUnit;
 
 /**
@@ -38,12 +33,14 @@ public class ScmBlobLfsRepository implements LargeFileRepository {
   private final String baseUri;
   private final Repository repository;
 
+  private AccessToken accessToken;
+
   /**
    * Creates a {@link ScmBlobLfsRepository} for the provided repository.
    *
-   * @param repository
+   * @param repository          The current scm repository this LFS repository is used for.
    * @param blobStore           The SCM Blobstore used for this @{@link LargeFileRepository}.
-   * @param tokenBuilderFactory
+   * @param tokenBuilderFactory The token builder used to create short lived access tokens.
    * @param baseUri             This URI is used to determine the actual URI for Upload / Download. Must be full URI (or
    */
 
@@ -97,26 +94,18 @@ public class ScmBlobLfsRepository implements LargeFileRepository {
     //LFS protocol has to provide the information on where to put or get the actual content, i. e.
     //the actual URI for up- and download.
 
-    ExpiringAction a = new ExpiringAction();
-    a.href = baseUri + id.getName();
+    return new ExpiringAction(baseUri + id.getName(), getAccessToken(scope));
+  }
 
-    AccessToken accessToken =
-      tokenBuilderFactory
+  private AccessToken getAccessToken(Scope scope) {
+    if (accessToken == null) {
+      accessToken = tokenBuilderFactory
         .create()
         .expiresIn(5, TimeUnit.MINUTES)
         .scope(scope)
         .build();
-    a.header = new HashMap<>();
-    a.header.put("Authorization", "Bearer " + accessToken.compact());
-    Instant expire = Instant.now().plus(5, ChronoUnit.MINUTES);
-    a.expires_at = new SimpleDateFormat("yyyy-MM-dd'T'HH:MM:ss'Z'").format(Date.from(expire));
-
-    return a;
+    }
+    return accessToken;
   }
 
-  @SuppressWarnings({"squid:ClassVariableVisibilityCheck", "squid:S00116"})
-  // This class is used for json serialization, only
-  private static class ExpiringAction extends Response.Action {
-    public String expires_at;
-  }
 }