UploadPack: Receive and parse client session-id

Before this change JGit did not support the session-id capability
implemented by native Git in UploadPack. This change implements
advertising the capability from the server and parsing the session-id
received from the client during an UploadPack operation.

Enable the transfer.advertisesid config setting to advertise the
capability from the server. The client may send a session-id capability
in response. If received, the value from this is parsed and available
via the getClientSID method on the UploadPack object.

This change does not add the capability to send a session-id from the
JGit client.

https://git-scm.com/docs/gitprotocol-capabilities#_session_idsession_id

Change-Id: Ib1b6929ff1b3a4528e767925b5e5c44b5d18182f
Signed-off-by: Josh Brown <sjoshbrown@google.com>

3 files changed, 85 insertions, 0 deletions

diff --git a/org.eclipse.jgit.test/tst/org/eclipse/jgit/transport/ProtocolV0ParserTest.java b/org.eclipse.jgit.test/tst/org/eclipse/jgit/transport/ProtocolV0ParserTest.java
index b2a4af30ab..61b7fb619a 100644
--- a/org.eclipse.jgit.test/tst/org/eclipse/jgit/transport/ProtocolV0ParserTest.java
+++ b/org.eclipse.jgit.test/tst/org/eclipse/jgit/transport/ProtocolV0ParserTest.java
@@ -98,6 +98,25 @@ public class ProtocolV0ParserTest {
 						"f900c8326a43303685c46b279b9f70411bff1a4b"));
 	}
 
+	@Test
+	public void testRecvWantsWithSessionID()
+			throws PackProtocolException, IOException {
+		PacketLineIn pckIn = formatAsPacketLine(String.join(" ", "want",
+				"4624442d68ee402a94364191085b77137618633e", "thin-pack",
+				"agent=JGit.test/0.0.1", "session-id=client-session-id", "\n"),
+				"want f900c8326a43303685c46b279b9f70411bff1a4b\n",
+				PacketLineIn.end());
+		ProtocolV0Parser parser = new ProtocolV0Parser(defaultConfig());
+		FetchV0Request request = parser.recvWants(pckIn);
+		assertTrue(request.getClientCapabilities()
+				.contains(GitProtocolConstants.OPTION_THIN_PACK));
+		assertEquals(1, request.getClientCapabilities().size());
+		assertEquals("client-session-id", request.getClientSID());
+		assertThat(request.getWantIds(),
+				hasOnlyObjectIds("4624442d68ee402a94364191085b77137618633e",
+						"f900c8326a43303685c46b279b9f70411bff1a4b"));
+	}
+
 	/*
 	 * First round of protocol v0 negotiation. Client send wants, no
 	 * capabilities.
diff --git a/org.eclipse.jgit.test/tst/org/eclipse/jgit/transport/ProtocolV2ParserTest.java b/org.eclipse.jgit.test/tst/org/eclipse/jgit/transport/ProtocolV2ParserTest.java
index 167b5b72c6..bab4a36cc4 100644
--- a/org.eclipse.jgit.test/tst/org/eclipse/jgit/transport/ProtocolV2ParserTest.java
+++ b/org.eclipse.jgit.test/tst/org/eclipse/jgit/transport/ProtocolV2ParserTest.java
@@ -361,4 +361,28 @@ public class ProtocolV2ParserTest {
 		assertEquals(2, req.getRefPrefixes().size());
 		assertThat(req.getRefPrefixes(), hasItems("refs/for", "refs/heads"));
 	}
+
+	@Test
+	public void testFetchWithSessionID() throws IOException {
+		PacketLineIn pckIn = formatAsPacketLine("session-id=the.client.sid",
+				PacketLineIn.end());
+
+		ProtocolV2Parser parser = new ProtocolV2Parser(
+				ConfigBuilder.start().allowFilter().done());
+		FetchV2Request request = parser.parseFetchRequest(pckIn);
+
+		assertEquals("the.client.sid", request.getClientSID());
+	}
+
+	@Test
+	public void testLsRefsWithSessionID() throws IOException {
+		PacketLineIn pckIn = formatAsPacketLine("session-id=the.client.sid",
+				PacketLineIn.delimiter(), PacketLineIn.end());
+
+		ProtocolV2Parser parser = new ProtocolV2Parser(
+				ConfigBuilder.getDefault());
+		LsRefsV2Request req = parser.parseLsRefsRequest(pckIn);
+
+		assertEquals("the.client.sid", req.getClientSID());
+	}
 }
diff --git a/org.eclipse.jgit.test/tst/org/eclipse/jgit/transport/UploadPackTest.java b/org.eclipse.jgit.test/tst/org/eclipse/jgit/transport/UploadPackTest.java
index 7131905850..df48afef35 100644
--- a/org.eclipse.jgit.test/tst/org/eclipse/jgit/transport/UploadPackTest.java
+++ b/org.eclipse.jgit.test/tst/org/eclipse/jgit/transport/UploadPackTest.java
@@ -2429,6 +2429,24 @@ public class UploadPackTest {
 	}
 
 	@Test
+	public void testGetSessionIDValueProtocolV0() throws Exception {
+		RevCommit one = remote.commit().message("1").create();
+		remote.update("one", one);
+
+		UploadPack up = new UploadPack(server);
+		ByteArrayInputStream send = linesAsInputStream(
+				"want " + one.getName() + " agent=JGit-test/1.2.3"
+						+ " session-id=client-session-id\n",
+				PacketLineIn.end(),
+				"have 11cedf1b796d44207da702f7d420684022fc0f09\n", "done\n");
+
+		ByteArrayOutputStream recv = new ByteArrayOutputStream();
+		up.upload(send, recv, null);
+
+		assertEquals(up.getClientSID(), "client-session-id");
+	}
+
+	@Test
 	public void testGetPeerAgentProtocolV2() throws Exception {
 		server.getConfig().setString(ConfigConstants.CONFIG_PROTOCOL_SECTION,
 				null, ConfigConstants.CONFIG_KEY_VERSION,
@@ -2452,6 +2470,30 @@ public class UploadPackTest {
 		assertEquals(up.getPeerUserAgent(), "JGit-test/1.2.4");
 	}
 
+	@Test
+	public void testGetSessionIDValueProtocolV2() throws Exception {
+		server.getConfig().setString(ConfigConstants.CONFIG_PROTOCOL_SECTION,
+				null, ConfigConstants.CONFIG_KEY_VERSION,
+				TransferConfig.ProtocolVersion.V2.version());
+
+		RevCommit one = remote.commit().message("1").create();
+		remote.update("one", one);
+
+		UploadPack up = new UploadPack(server);
+		up.setExtraParameters(Sets.of("version=2"));
+
+		ByteArrayInputStream send = linesAsInputStream("command=fetch\n",
+				"agent=JGit-test/1.2.4\n", "session-id=client-session-id\n",
+				PacketLineIn.delimiter(), "want " + one.getName() + "\n",
+				"have 11cedf1b796d44207da702f7d420684022fc0f09\n", "done\n",
+				PacketLineIn.end());
+
+		ByteArrayOutputStream recv = new ByteArrayOutputStream();
+		up.upload(send, recv, null);
+
+		assertEquals(up.getClientSID(), "client-session-id");
+	}
+
 	private static class RejectAllRefFilter implements RefFilter {
 		@Override
 		public Map<String, Ref> filter(Map<String, Ref> refs) {