LFS: Enable LFS support for the CLI, better error handling

Enable LFS support for the CLI by registering the according filters.

Errors during filter creation must be propagated up the call stack, as a
failure to create a filter should be treated as fatal if the filter is
required.

Change-Id: I3833757839bdda97cd01b6c21c1613d199e2692d
Signed-off-by: Markus Duft <markus.duft@ssi-schaefer.com>

org.eclipse.jgit.lfs.server.test/META-INF/MANIFEST.MF

@@ -29,6 +29,7 @@ Import-Package: javax.servlet;version="[3.1.0,4.0.0)",
  org.eclipse.jetty.util.security;version="[9.4.5,10.0.0)",
  org.eclipse.jetty.util.thread;version="[9.4.5,10.0.0)",
  org.eclipse.jgit.api;version="[4.11.0,4.12.0)",
+ org.eclipse.jgit.api.errors;version="[4.11.0,4.12.0)",
  org.eclipse.jgit.internal.storage.file;version="[4.11.0,4.12.0)",
  org.eclipse.jgit.junit;version="[4.11.0,4.12.0)",
  org.eclipse.jgit.junit.http;version="[4.11.0,4.12.0)",

org.eclipse.jgit.lfs.server.test/tst/org/eclipse/jgit/lfs/server/fs/CheckoutTest.java

@@ -49,10 +49,13 @@
 import java.nio.file.Path;
 
 import org.eclipse.jgit.api.Git;
+import org.eclipse.jgit.api.errors.JGitInternalException;
 import org.eclipse.jgit.junit.JGitTestUtil;
 import org.eclipse.jgit.junit.TestRepository;
 import org.eclipse.jgit.lfs.BuiltinLFS;
+import org.eclipse.jgit.lfs.lib.Constants;
 import org.eclipse.jgit.lfs.lib.LongObjectId;
+import org.eclipse.jgit.lib.ConfigConstants;
 import org.eclipse.jgit.lib.Repository;
 import org.eclipse.jgit.lib.StoredConfig;
 import org.eclipse.jgit.storage.file.FileRepositoryBuilder;
@@ -78,8 +81,12 @@ public void setup() throws Exception {
 				.create(tmp.resolve(".git").toFile());
 		db.create();
 		StoredConfig cfg = db.getConfig();
-		cfg.setString("filter", "lfs", "usejgitbuiltin", "true");
-		cfg.setString("lfs", null, "url", server.getURI().toString() + "/lfs");
+		cfg.setBoolean(ConfigConstants.CONFIG_FILTER_SECTION, Constants.LFS,
+				ConfigConstants.CONFIG_KEY_USEJGITBUILTIN, true);
+		cfg.setBoolean(ConfigConstants.CONFIG_FILTER_SECTION, Constants.LFS,
+				ConfigConstants.CONFIG_KEY_REQUIRED, false);
+		cfg.setString(Constants.LFS, null, "url",
+				server.getURI().toString() + "/lfs");
 		cfg.save();
 
 		tdb = new TestRepository<>(db);
@@ -112,6 +119,17 @@ public void testUnknownContent() throws Exception {
 				server.getRequests().toString());
 	}
 
+	@Test(expected = JGitInternalException.class)
+	public void testUnknownContentRequired() throws Exception {
+		StoredConfig cfg = tdb.getRepository().getConfig();
+		cfg.setBoolean(ConfigConstants.CONFIG_FILTER_SECTION, Constants.LFS,
+				ConfigConstants.CONFIG_KEY_REQUIRED, true);
+		cfg.save();
+
+		// must throw
+		git.checkout().setName("test").call();
+	}
+
 	@Test
 	public void testKnownContent() throws Exception {
 		putContent(

org.eclipse.jgit.lfs/resources/org/eclipse/jgit/lfs/internal/LfsText.properties

@@ -5,6 +5,7 @@ inconsistentContentLength=Unexpected content length reported by LFS server ({0})
 invalidLongId=Invalid id: {0}
 invalidLongIdLength=Invalid id length {0}; should be {1}
 lfsUnavailable=LFS is not available for repository {0}
+protocolError=LFS Protocol Error {0}: {1}
 requiredHashFunctionNotAvailable=Required hash function {0} not available.
 repositoryNotFound=Repository {0} not found
 repositoryReadOnly=Repository {0} is read-only

org.eclipse.jgit.lfs/src/org/eclipse/jgit/lfs/SmudgeFilter.java

@@ -182,6 +182,11 @@ public static Collection<Path> downloadLfsResource(Lfs lfs, Repository db,
 			Protocol.Response resp = gson.fromJson(reader,
 					Protocol.Response.class);
 			for (Protocol.ObjectInfo o : resp.objects) {
+				if (o.error != null) {
+					throw new IOException(
+							MessageFormat.format(LfsText.get().protocolError,
+									o.error.code, o.error.message));
+				}
 				if (o.actions == null) {
 					continue;
 				}

org.eclipse.jgit.lfs/src/org/eclipse/jgit/lfs/internal/LfsText.java

@@ -67,6 +67,7 @@ public static LfsText get() {
 	/***/ public String invalidLongId;
 	/***/ public String invalidLongIdLength;
 	/***/ public String lfsUnavailable;
+	/***/ public String protocolError;
 	/***/ public String requiredHashFunctionNotAvailable;
 	/***/ public String repositoryNotFound;
 	/***/ public String repositoryReadOnly;

org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/Main.java

@@ -132,6 +132,9 @@ public Thread newThread(Runnable taskBody) {
 	 * @throws java.lang.Exception
 	 */
 	public static void main(final String[] argv) throws Exception {
+		// make sure built-in filters are registered
+		BuiltinLFS.register();
+
 		new Main().run(argv);
 	}
 

org.eclipse.jgit/src/org/eclipse/jgit/dircache/DirCacheCheckout.java

@@ -67,6 +67,7 @@
 import org.eclipse.jgit.errors.MissingObjectException;
 import org.eclipse.jgit.events.WorkingTreeModifiedEvent;
 import org.eclipse.jgit.internal.JGitText;
+import org.eclipse.jgit.lib.ConfigConstants;
 import org.eclipse.jgit.lib.Constants;
 import org.eclipse.jgit.lib.CoreConfig.AutoCRLF;
 import org.eclipse.jgit.lib.CoreConfig.EolStreamType;
@@ -1539,6 +1540,9 @@ private static void runExternalFilterCommand(Repository repo,
 	private static void runBuiltinFilterCommand(Repository repo,
 			CheckoutMetadata checkoutMetadata, ObjectLoader ol,
 			OutputStream channel) throws MissingObjectException, IOException {
+		boolean isMandatory = repo.getConfig().getBoolean(
+				ConfigConstants.CONFIG_FILTER_SECTION, "lfs",
+				ConfigConstants.CONFIG_KEY_REQUIRED, false);
 		FilterCommand command = null;
 		try {
 			command = FilterCommandRegistry.createFilterCommand(
@@ -1546,9 +1550,14 @@ private static void runBuiltinFilterCommand(Repository repo,
 					channel);
 		} catch (IOException e) {
 			LOG.error(JGitText.get().failedToDetermineFilterDefinition, e);
-			// In case an IOException occurred during creating of the command
-			// then proceed as if there would not have been a builtin filter.
-			ol.copyTo(channel);
+			if (!isMandatory) {
+				// In case an IOException occurred during creating of the
+				// command then proceed as if there would not have been a
+				// builtin filter (only if the filter is not mandatory).
+				ol.copyTo(channel);
+			} else {
+				throw e;
+			}
 		}
 		if (command != null) {
 			while (command.run() != -1) {