[PATCH 0/6] cat-file: add remote-object-info to batch-command

@@ -1313,13 +1313,13 @@ static int add_haves(struct fetch_negotiator *negotiator,
 	return haves_added;
 }
 
-static void write_fetch_command_and_capabilities(struct strbuf *req_buf,
-						 const struct string_list *server_options)
+static void write_command_and_capabilities(struct strbuf *req_buf,
+						 const struct string_list *server_options, const char* command)
 {
 	const char *hash_name;
 
-	ensure_server_supports_v2("fetch");
-	packet_buf_write(req_buf, "command=fetch");
+	ensure_server_supports_v2(command);
+	packet_buf_write(req_buf, "command=%s", command);
 	if (server_supports_v2("agent"))
 		packet_buf_write(req_buf, "agent=%s", git_user_agent_sanitized());
 	if (advertise_sid && server_supports_v2("session-id"))

@@ -1355,7 +1355,7 @@ static int send_fetch_request(struct fetch_negotiator *negotiator, int fd_out,
 	int done_sent = 0;
 	struct strbuf req_buf = STRBUF_INIT;
 
-	write_fetch_command_and_capabilities(&req_buf, args->server_options);
+	write_command_and_capabilities(&req_buf, args->server_options, "fetch");
 
 	if (args->use_thin_pack)
 		packet_buf_write(&req_buf, "thin-pack");

@@ -2163,7 +2163,7 @@ void negotiate_using_fetch(const struct oid_array *negotiation_tips,
 					   the_repository, "%d",
 					   negotiation_round);
 		strbuf_reset(&req_buf);
-		write_fetch_command_and_capabilities(&req_buf, server_options);
+		write_command_and_capabilities(&req_buf, server_options, "fetch");
 
 		packet_buf_write(&req_buf, "wait-for-done");
 

@@ -1676,18 +1676,18 @@ static struct ref *do_fetch_pack_v2(struct fetch_pack_args *args,
 		reader.me = "fetch-pack";
 	}
 
+	/* v2 supports these by default */
+	allow_unadvertised_object_request |= ALLOW_REACHABLE_SHA1;
+	use_sideband = 2;
+	if (args->depth > 0 || args->deepen_since || args->deepen_not)
+		args->deepen = 1;
+
 	while (state != FETCH_DONE) {
 		switch (state) {
 		case FETCH_CHECK_LOCAL:
 			sort_ref_list(&ref, ref_compare_name);
 			QSORT(sought, nr_sought, cmp_ref_by_name);
 
-			/* v2 supports these by default */
-			allow_unadvertised_object_request |= ALLOW_REACHABLE_SHA1;
-			use_sideband = 2;
-			if (args->depth > 0 || args->deepen_since || args->deepen_not)
-				args->deepen = 1;
-
 			/* Filter 'ref' by 'sought' and those that aren't local */
 			mark_complete_and_common_ref(negotiator, args, &ref);
 			filter_refs(args, &ref, sought, nr_sought);

@@ -68,7 +68,7 @@ static void session_id_receive(struct repository *r UNUSED,
 	trace2_data_string("transfer", NULL, "client-sid", client_sid);
 }
 
-static int object_info_advertise(struct repository *r, struct strbuf *value UNUSED)
+static int object_info_advertise(struct repository *r, struct strbuf *value)
 {
 	if (advertise_object_info == -1 &&
 	    repo_config_get_bool(r, "transfer.advertiseobjectinfo",

@@ -76,6 +76,8 @@ static int object_info_advertise(struct repository *r, struct strbuf *value UNUS
 		/* disabled by default */
 		advertise_object_info = 0;
 	}
+	if (value && advertise_object_info)
+		strbuf_addstr(value, "size");
 	return advertise_object_info;
 }
 

@@ -1345,6 +1345,27 @@ static void write_command_and_capabilities(struct strbuf *req_buf,
 	packet_buf_delim(req_buf);
 }
 
+void send_object_info_request(int fd_out, struct object_info_args *args)
+{
+	struct strbuf req_buf = STRBUF_INIT;
+
+	write_command_and_capabilities(&req_buf, args->server_options, "object-info");
+
+	if (unsorted_string_list_has_string(args->object_info_options, "size"))
+		packet_buf_write(&req_buf, "size");
+
+	if (args->oids) {
+		for (size_t i = 0; i < args->oids->nr; i++)
+			packet_buf_write(&req_buf, "oid %s", oid_to_hex(&args->oids->oid[i]));
+	}
+
+	packet_buf_flush(&req_buf);
+	if (write_in_full(fd_out, req_buf.buf, req_buf.len) < 0)
+		die_errno(_("unable to write request to remote"));
+
+	strbuf_release(&req_buf);
+}
+
 static int send_fetch_request(struct fetch_negotiator *negotiator, int fd_out,
 			      struct fetch_pack_args *args,
 			      const struct ref *wants, struct oidset *common,

@@ -1682,6 +1703,9 @@ static struct ref *do_fetch_pack_v2(struct fetch_pack_args *args,
 	if (args->depth > 0 || args->deepen_since || args->deepen_not)
 		args->deepen = 1;
 
+	if (args->object_info)
+		state = FETCH_SEND_REQUEST;
+
 	while (state != FETCH_DONE) {
 		switch (state) {
 		case FETCH_CHECK_LOCAL:

@@ -16,6 +16,7 @@ struct fetch_pack_args {
 	const struct string_list *deepen_not;
 	struct list_objects_filter_options filter_options;
 	const struct string_list *server_options;
+	struct object_info **object_info_data;
 
 	/*
 	 * If not NULL, during packfile negotiation, fetch-pack will send "have"

@@ -42,6 +43,7 @@ struct fetch_pack_args {
 	unsigned reject_shallow_remote:1;
 	unsigned deepen:1;
 	unsigned refetch:1;
+	unsigned object_info:1;
 
 	/*
 	 * Indicate that the remote of this request is a promisor remote. The

@@ -68,6 +70,12 @@ struct fetch_pack_args {
 	unsigned connectivity_checked:1;
 };
 
+struct object_info_args {
+	struct string_list *object_info_options;
+	const struct string_list *server_options;
+	struct oid_array *oids;
+};
+
 /*
  * sought represents remote references that should be updated from.
  * On return, the names that were found on the remote will have been

@@ -101,4 +109,6 @@ void negotiate_using_fetch(const struct oid_array *negotiation_tips,
  */
 int report_unmatched_refs(struct ref **sought, int nr_sought);
 
+void send_object_info_request(int fd_out, struct object_info_args *args);
+
 #endif

@@ -697,13 +697,17 @@ static int fetch_refs(struct transport *transport,
 
 	/*
 	 * If we reach here, then the server, the client, and/or the transport
-	 * helper does not support protocol v2. --negotiate-only requires
-	 * protocol v2.
+	 * helper does not support protocol v2. --negotiate-only and cat-file remote-object-info
+	 * require protocol v2.
 	 */
 	if (data->transport_options.acked_commits) {
 		warning(_("--negotiate-only requires protocol v2"));
 		return -1;
 	}
+	if (transport->smart_options->object_info) {
+		// fail the command explicitly to avoid further commands input
+		die(_("remote-object-info requires protocol v2"));
+	}
 
 	if (!data->get_refs_list_called)
 		get_refs_list_using_list(transport, 0);

@@ -363,6 +363,73 @@ static struct ref *handshake(struct transport *transport, int for_push,
 	return refs;
 }
 
+static int fetch_object_info(struct transport *transport, struct object_info **object_info_data)
+{
+	int size_index = -1;
+	struct git_transport_data *data = transport->data;
+	struct object_info_args args;
+	struct packet_reader reader;
+
+	memset(&args, 0, sizeof(args));
+	args.server_options = transport->server_options;
+	args.object_info_options = transport->smart_options->object_info_options;
+	args.oids = transport->smart_options->object_info_oids;
+
+	connect_setup(transport, 0);
+	packet_reader_init(&reader, data->fd[0], NULL, 0,
+			PACKET_READ_CHOMP_NEWLINE |
+			PACKET_READ_GENTLE_ON_EOF |
+			PACKET_READ_DIE_ON_ERR_PACKET);
+	data->version = discover_version(&reader);
+
+	transport->hash_algo = reader.hash_algo;
+
+	switch (data->version) {
+	case protocol_v2:
+		if (!server_supports_v2("object-info"))
+			return -1;
+		if (unsorted_string_list_has_string(args.object_info_options, "size")
+				&& !server_supports_feature("object-info", "size", 0)) {
+			return -1;
+		}
+		send_object_info_request(data->fd[1], &args);
+		break;
+	case protocol_v1:
+	case protocol_v0:
+		die(_("wrong protocol version. expected v2"));
+	case protocol_unknown_version:
+		BUG("unknown protocol version");
+	}
+
+	for (size_t i = 0; i < args.object_info_options->nr; i++) {
+		if (packet_reader_read(&reader) != PACKET_READ_NORMAL) {
+			check_stateless_delimiter(transport->stateless_rpc, &reader, "stateless delimiter expected");
+			return -1;
+		}
+		if (unsorted_string_list_has_string(args.object_info_options, reader.line)) {
+			if (!strcmp(reader.line, "size"))
+				size_index = i;
+			continue;
+		}
+		return -1;
+	}
+
+	for (size_t i = 0; packet_reader_read(&reader) == PACKET_READ_NORMAL && i < args.oids->nr; i++){
+		struct string_list object_info_values = STRING_LIST_INIT_DUP;
+
+		string_list_split(&object_info_values, reader.line, ' ', -1);
+		if (0 <= size_index) {
+			if (!strcmp(object_info_values.items[1 + size_index].string, ""))
+				die("object-info: not our ref %s",
+					object_info_values.items[0].string);
+			*(*object_info_data)[i].sizep = strtoul(object_info_values.items[1 + size_index].string, NULL, 10);
+		}
+	}
+	check_stateless_delimiter(transport->stateless_rpc, &reader, "stateless delimiter expected");
+
+	return 0;
+}
+
 static struct ref *get_refs_via_connect(struct transport *transport, int for_push,
 					struct transport_ls_refs_options *options)
 {

@@ -410,6 +477,7 @@ static int fetch_refs_via_pack(struct transport *transport,
 	struct ref *refs = NULL;
 	struct fetch_pack_args args;
 	struct ref *refs_tmp = NULL;
+	struct ref *object_info_refs = xcalloc(1, sizeof (struct ref));
 
 	memset(&args, 0, sizeof(args));
 	args.uploadpack = data->options.uploadpack;

@@ -436,11 +504,27 @@ static int fetch_refs_via_pack(struct transport *transport,
 	args.server_options = transport->server_options;
 	args.negotiation_tips = data->options.negotiation_tips;
 	args.reject_shallow_remote = transport->smart_options->reject_shallow;
-
-	if (!data->finished_handshake) {
-		int i;
+	args.object_info = transport->smart_options->object_info;
+
+	if (transport->smart_options && transport->smart_options->object_info) {
+		struct ref *ref = object_info_refs;
+
+		if (!fetch_object_info(transport, data->options.object_info_data))
+			goto cleanup;
+		args.object_info_data = data->options.object_info_data;
+		args.quiet = 1;
+		args.no_progress = 1;
+		for (size_t i = 0; i < transport->smart_options->object_info_oids->nr; i++) {
+			struct ref *temp_ref = xcalloc(1, sizeof (struct ref));
+			temp_ref->old_oid = *(transport->smart_options->object_info_oids->oid + i);
+			temp_ref->exact_oid = 1;
+			ref->next = temp_ref;
+			ref = ref->next;
+		}
+		transport->remote_refs = object_info_refs->next;
+	} else if (!data->finished_handshake) {
 		int must_list_refs = 0;
-		for (i = 0; i < nr_heads; i++) {
+		for (int i = 0; i < nr_heads; i++) {
 			if (!to_fetch[i]->exact_oid) {
 				must_list_refs = 1;
 				break;

@@ -478,11 +562,18 @@ static int fetch_refs_via_pack(struct transport *transport,
 			  &transport->pack_lockfiles, data->version);
 
 	data->finished_handshake = 0;
+	if (args.object_info) {
+		struct ref *ref_cpy_reader = object_info_refs->next;
+		for (int i = 0; ref_cpy_reader; i++) {
+			oid_object_info_extended(the_repository, &ref_cpy_reader->old_oid, &(*args.object_info_data)[i], OBJECT_INFO_LOOKUP_REPLACE);
+			ref_cpy_reader = ref_cpy_reader->next;
+		}
+	}
 	data->options.self_contained_and_connected =
 		args.self_contained_and_connected;
 	data->options.connectivity_checked = args.connectivity_checked;
 
-	if (!refs)
+	if (!refs && !args.object_info)
 		ret = -1;
 	if (report_unmatched_refs(to_fetch, nr_heads))
 		ret = -1;

@@ -498,6 +589,7 @@ static int fetch_refs_via_pack(struct transport *transport,
 	free_refs(refs_tmp);
 	free_refs(refs);
 	list_objects_filter_release(&args.filter_options);
+	free_refs(object_info_refs);
 	return ret;
 }
 

@@ -5,6 +5,7 @@
 #include "remote.h"
 #include "list-objects-filter-options.h"
 #include "string-list.h"
+#include "object-store.h"
 
 struct git_transport_options {
 	unsigned thin : 1;

@@ -30,6 +31,12 @@ struct git_transport_options {
 	 */
 	unsigned connectivity_checked:1;
 
+	/*
+	 * Transport will attempt to pull only object-info. Fallbacks
+	 * to pulling entire object if object-info is not supported.
+	 */
+	unsigned object_info : 1;
+
 	int depth;
 	const char *deepen_since;
 	const struct string_list *deepen_not;

@@ -53,6 +60,10 @@ struct git_transport_options {
 	 * common commits to this oidset instead of fetching any packfiles.
 	 */
 	struct oidset *acked_commits;
+
+	struct oid_array *object_info_oids;
+	struct object_info **object_info_data;
+	struct string_list *object_info_options;
 };
 
 enum transport_family {

@@ -668,12 +668,10 @@ static void dispatch_calls(struct batch_options *opt,
 		struct queued_cmd *cmd,
 		int nr)
 {
-	int i;
-
 	if (!opt->buffer_output)
 		die(_("flush is only for --buffer mode"));
 
-	for (i = 0; i < nr; i++)
+	for (int i = 0; i < nr; i++)
 		cmd[i].fn(opt, cmd[i].line, output, data);
 
 	fflush(stdout);

@@ -681,9 +679,7 @@ static void dispatch_calls(struct batch_options *opt,
 
 static void free_cmds(struct queued_cmd *cmd, size_t *nr)
 {
-	size_t i;
-
-	for (i = 0; i < *nr; i++)
+	for (size_t i = 0; i < *nr; i++)
 		FREE_AND_NULL(cmd[i].line);
 
 	*nr = 0;

@@ -709,7 +705,6 @@ static void batch_objects_command(struct batch_options *opt,
 	size_t alloc = 0, nr = 0;
 
 	while (strbuf_getdelim_strip_crlf(&input, stdin, opt->input_delim) != EOF) {
-		int i;
 		const struct parse_cmd *cmd = NULL;
 		const char *p = NULL, *cmd_end;
 		struct queued_cmd call = {0};

@@ -719,7 +714,7 @@ static void batch_objects_command(struct batch_options *opt,
 		if (isspace(*input.buf))
 			die(_("whitespace before command: '%s'"), input.buf);
 
-		for (i = 0; i < ARRAY_SIZE(commands); i++) {
+		for (int i = 0; i < ARRAY_SIZE(commands); i++) {
 			if (!skip_prefix(input.buf, commands[i].name, &cmd_end))
 				continue;
 

@@ -149,6 +149,12 @@ info <object>::
 	Print object info for object reference `<object>`. This corresponds to the
 	output of `--batch-check`.
 
+remote-object-info <remote> <object>...::
+	Print object info for object references `<object>` at specified <remote> without
+	downloading object from remote.
+	Error when no object references is provided.
+	This command may be combined with `--buffer`.
+
 flush::
 	Used with `--buffer` to execute all preceding commands that were issued
 	since the beginning or since the last flush was issued. When `--buffer`

@@ -290,7 +296,8 @@ newline. The available atoms are:
 	The full hex representation of the object name.
 
 `objecttype`::
-	The type of the object (the same as `cat-file -t` reports).
+	The type of the object (the same as `cat-file -t` reports). See
+	`CAVEATS` below. Not supported by `remote-object-info`.
 
 `objectsize`::
 	The size, in bytes, of the object (the same as `cat-file -s`

@@ -298,13 +305,14 @@ newline. The available atoms are:
 
 `objectsize:disk`::
 	The size, in bytes, that the object takes up on disk. See the
-	note about on-disk sizes in the `CAVEATS` section below.
+	note about on-disk sizes in the `CAVEATS` section below. Not
+	supported by `remote-object-info`.
 
 `deltabase`::
 	If the object is stored as a delta on-disk, this expands to the
 	full hex representation of the delta base object name.
 	Otherwise, expands to the null OID (all zeroes). See `CAVEATS`
-	below.
+	below. Not supported by `remote-object-info`.
 
 `rest`::
 	If this atom is used in the output string, input lines are split

@@ -314,7 +322,9 @@ newline. The available atoms are:
 	line) are output in place of the `%(rest)` atom.
 
 If no format is specified, the default format is `%(objectname)
-%(objecttype) %(objectsize)`.
+%(objecttype) %(objectsize)`, except remote-object-info command who uses
+`%(objectname) %(objectsize)` for now because "%(objecttype)" is not supported yet.
+When "%(objecttype)" is supported, default format should be unified.
 
 If `--batch` is specified, or if `--batch-command` is used with the `contents`
 command, the object information is followed by the object contents (consisting

@@ -396,6 +406,10 @@ scripting purposes.
 CAVEATS
 -------
 
+Note that since objecttype, objectsize:disk and deltabase are currently not supported by the
+remote-object-info, git will error and exit when they are in the format string.
+
+
 Note that the sizes of objects on disk are reported accurately, but care
 should be taken in drawing conclusions about which refs or objects are
 responsible for disk usage. The size of a packed non-delta object may be

@@ -24,6 +24,9 @@
 #include "promisor-remote.h"
 #include "mailmap.h"
 #include "write-or-die.h"
+#include "alias.h"
+#include "remote.h"
+#include "transport.h"
 
 enum batch_mode {
 	BATCH_MODE_CONTENTS,

@@ -42,9 +45,14 @@ struct batch_options {
 	char input_delim;
 	char output_delim;
 	const char *format;
+	int use_remote_info;
 };
 
+#define DEFAULT_FORMAT "%(objectname) %(objecttype) %(objectsize)"
+
 static const char *force_path;
+static struct object_info *remote_object_info;
+static struct oid_array object_info_oids = OID_ARRAY_INIT;
 
 static struct string_list mailmap = STRING_LIST_INIT_NODUP;
 static int use_mailmap;

@@ -508,7 +516,6 @@ static void batch_object_write(const char *obj_name,
 	}
 
 	batch_write(opt, scratch->buf, scratch->len);
-
 	if (opt->batch_mode == BATCH_MODE_CONTENTS) {
 		print_object_or_die(opt, data);
 		batch_write(opt, &opt->output_delim, 1);

@@ -526,51 +533,118 @@ static void batch_one_object(const char *obj_name,
 		(opt->follow_symlinks ? GET_OID_FOLLOW_SYMLINKS : 0);
 	enum get_oid_result result;
 
-	result = get_oid_with_context(the_repository, obj_name,
-				      flags, &data->oid, &ctx);
-	if (result != FOUND) {
-		switch (result) {
-		case MISSING_OBJECT:
-			printf("%s missing%c", obj_name, opt->output_delim);
-			break;
-		case SHORT_NAME_AMBIGUOUS:
-			printf("%s ambiguous%c", obj_name, opt->output_delim);
-			break;
-		case DANGLING_SYMLINK:
-			printf("dangling %"PRIuMAX"%c%s%c",
-			       (uintmax_t)strlen(obj_name),
-			       opt->output_delim, obj_name, opt->output_delim);
-			break;
-		case SYMLINK_LOOP:
-			printf("loop %"PRIuMAX"%c%s%c",
-			       (uintmax_t)strlen(obj_name),
-			       opt->output_delim, obj_name, opt->output_delim);
-			break;
-		case NOT_DIR:
-			printf("notdir %"PRIuMAX"%c%s%c",
-			       (uintmax_t)strlen(obj_name),
-			       opt->output_delim, obj_name, opt->output_delim);
-			break;
-		default:
-			BUG("unknown get_sha1_with_context result %d\n",
-			       result);
-			break;
+	if (!opt->use_remote_info) {
+		result = get_oid_with_context(the_repository, obj_name,
+						flags, &data->oid, &ctx);
+		if (result != FOUND) {
+			switch (result) {
+			case MISSING_OBJECT:
+				printf("%s missing%c", obj_name, opt->output_delim);
+				break;
+			case SHORT_NAME_AMBIGUOUS:
+				printf("%s ambiguous%c", obj_name, opt->output_delim);
+				break;
+			case DANGLING_SYMLINK:
+				printf("dangling %"PRIuMAX"%c%s%c",
+					(uintmax_t)strlen(obj_name),
+					opt->output_delim, obj_name, opt->output_delim);
+				break;
+			case SYMLINK_LOOP:
+				printf("loop %"PRIuMAX"%c%s%c",
+					(uintmax_t)strlen(obj_name),
+					opt->output_delim, obj_name, opt->output_delim);
+				break;
+			case NOT_DIR:
+				printf("notdir %"PRIuMAX"%c%s%c",
+					(uintmax_t)strlen(obj_name),
+					opt->output_delim, obj_name, opt->output_delim);
+				break;
+			default:
+				BUG("unknown get_sha1_with_context result %d\n",
+					result);
+				break;
+			}
+			fflush(stdout);
+			return;
 		}
-		fflush(stdout);
-		return;
-	}
 
-	if (ctx.mode == 0) {
-		printf("symlink %"PRIuMAX"%c%s%c",
-		       (uintmax_t)ctx.symlink_path.len,
-		       opt->output_delim, ctx.symlink_path.buf, opt->output_delim);
-		fflush(stdout);
-		return;
+		if (ctx.mode == 0) {
+			printf("symlink %"PRIuMAX"%c%s%c",
+				(uintmax_t)ctx.symlink_path.len,
+				opt->output_delim, ctx.symlink_path.buf, opt->output_delim);
+			fflush(stdout);
+			return;
+		}
 	}
 
 	batch_object_write(obj_name, scratch, opt, data, NULL, 0);
 }
 
+static int get_remote_info(struct batch_options *opt, int argc, const char **argv)
+{
+	int retval = 0;
+	struct remote *remote = NULL;
+	struct object_id oid;
+	struct string_list object_info_options = STRING_LIST_INIT_NODUP;
+	static struct transport *gtransport;
+
+	/*
+	 * Change the format to "%(objectname) %(objectsize)" when
+	 * remote-object-info command is used. Once we start supporting objecttype
+	 * the default format should change to DEFAULT_FORMAT
+	*/
+	if (!opt->format) {
+		opt->format = "%(objectname) %(objectsize)";
+	}
+
+	remote = remote_get(argv[0]);
+	if (!remote)
+		die(_("must supply valid remote when using remote-object-info"));
+	oid_array_clear(&object_info_oids);
+	for (size_t i = 1; i < argc; i++) {
+		if (get_oid_hex(argv[i], &oid))
+			die(_("Not a valid object name %s"), argv[i]);
+		oid_array_append(&object_info_oids, &oid);
+	}
+
+	gtransport = transport_get(remote, NULL);
+	if (gtransport->smart_options) {
+		int include_size = 0;
+
+		CALLOC_ARRAY(remote_object_info, object_info_oids.nr);
+		gtransport->smart_options->object_info = 1;
+		gtransport->smart_options->object_info_oids = &object_info_oids;
+		/*
+		 * 'size' is the only option currently supported.
+		 * Other options that are passed in the format will exit with error.
+		 */
+		if (strstr(opt->format, "%(objectsize)")) {
+			string_list_append(&object_info_options, "size");
+			include_size = 1;
+		}
+		if (strstr(opt->format, "%(objecttype)")) {
+			die(_("objecttype is currently not supported with remote-object-info"));
+		}
+		if (strstr(opt->format, "%(objectsize:disk)"))
+			die(_("objectsize:disk is currently not supported with remote-object-info"));
+		if (strstr(opt->format, "%(deltabase)"))
+			die(_("deltabase is currently not supported with remote-object-info"));
+		if (object_info_options.nr > 0) {
+			gtransport->smart_options->object_info_options = &object_info_options;
+			for (size_t i = 0; i < object_info_oids.nr; i++) {
+				if (include_size)
+					remote_object_info[i].sizep = xcalloc(1, sizeof(long));
+			}
+			gtransport->smart_options->object_info_data = &remote_object_info;
+			retval = transport_fetch_refs(gtransport, NULL);
+		}
+	} else {
+		retval = -1;
+	}
+
+	return retval;
+}
+
 struct object_cb_data {
 	struct batch_options *opt;
 	struct expand_data *expand;

@@ -642,6 +716,7 @@ typedef void (*parse_cmd_fn_t)(struct batch_options *, const char *,
 struct queued_cmd {
 	parse_cmd_fn_t fn;
 	char *line;
+	const char *name;
 };
 
 static void parse_cmd_contents(struct batch_options *opt,

@@ -662,6 +737,55 @@ static void parse_cmd_info(struct batch_options *opt,
 	batch_one_object(line, output, opt, data);
 }
 
+static const struct parse_cmd {
+	const char *name;
+	parse_cmd_fn_t fn;
+	unsigned takes_args;
+} commands[] = {
+	{ "contents", parse_cmd_contents, 1 },
+	{ "info", parse_cmd_info, 1 },
+	{ "remote-object-info", parse_cmd_info, 1 },
+	{ "flush", NULL, 0 },
+};
+
+static void parse_remote_info(struct batch_options *opt,
+			   char *line,
+			   struct strbuf *output,
+			   struct expand_data *data,
+			   const struct parse_cmd *p_cmd,
+			   struct queued_cmd *q_cmd)
+{
+	int count;
+	const char **argv;
+
+	count = split_cmdline(line, &argv);
+	if (get_remote_info(opt, count, argv))
+		goto cleanup;
+	opt->use_remote_info = 1;
+	data->skip_object_info = 1;
+	data->mark_query = 0;
+	for (size_t i = 0; i < object_info_oids.nr; i++) {
+		if (remote_object_info[i].sizep)
+			data->size = *remote_object_info[i].sizep;
+		if (remote_object_info[i].typep)
+			data->type = *remote_object_info[i].typep;
+
+		data->oid = object_info_oids.oid[i];
+		if (p_cmd)
+			p_cmd->fn(opt, argv[i+1], output, data);
+		else
+			q_cmd->fn(opt, argv[i+1], output, data);
+	}
+	opt->use_remote_info = 0;
+	data->skip_object_info = 0;
+	data->mark_query = 1;
+
+cleanup:
+	for (size_t i = 0; i < object_info_oids.nr; i++)
+		free_object_info_contents(&remote_object_info[i]);
+	free(remote_object_info);
+}
+
 static void dispatch_calls(struct batch_options *opt,
 		struct strbuf *output,
 		struct expand_data *data,

@@ -671,8 +795,12 @@ static void dispatch_calls(struct batch_options *opt,
 	if (!opt->buffer_output)
 		die(_("flush is only for --buffer mode"));
 
-	for (int i = 0; i < nr; i++)
-		cmd[i].fn(opt, cmd[i].line, output, data);
+	for (int i = 0; i < nr; i++) {
+		if (!strcmp(cmd[i].name, "remote-object-info"))
+			parse_remote_info(opt, cmd[i].line, output, data, NULL, &cmd[i]);
+		else
+			cmd[i].fn(opt, cmd[i].line, output, data);
+	}
 
 	fflush(stdout);
 }

@@ -685,17 +813,6 @@ static void free_cmds(struct queued_cmd *cmd, size_t *nr)
 	*nr = 0;
 }
 
-
-static const struct parse_cmd {
-	const char *name;
-	parse_cmd_fn_t fn;
-	unsigned takes_args;
-} commands[] = {
-	{ "contents", parse_cmd_contents, 1},
-	{ "info", parse_cmd_info, 1},
-	{ "flush", NULL, 0},
-};
-
 static void batch_objects_command(struct batch_options *opt,
 				    struct strbuf *output,
 				    struct expand_data *data)

@@ -740,11 +857,17 @@ static void batch_objects_command(struct batch_options *opt,
 			dispatch_calls(opt, output, data, queued_cmd, nr);
 			free_cmds(queued_cmd, &nr);
 		} else if (!opt->buffer_output) {
-			cmd->fn(opt, p, output, data);
+			if (!strcmp(cmd->name, "remote-object-info")) {
+				char *line = xstrdup_or_null(p);
+				parse_remote_info(opt, line, output, data, cmd, NULL);
+			} else {
+				cmd->fn(opt, p, output, data);
+			}
 		} else {
 			ALLOC_GROW(queued_cmd, nr + 1, alloc);
 			call.fn = cmd->fn;
 			call.line = xstrdup_or_null(p);
+			call.name = cmd->name;
 			queued_cmd[nr++] = call;
 		}
 	}

@@ -761,8 +884,6 @@ static void batch_objects_command(struct batch_options *opt,
 	strbuf_release(&input);
 }
 
-#define DEFAULT_FORMAT "%(objectname) %(objecttype) %(objectsize)"
-
 static int batch_objects(struct batch_options *opt)
 {
 	struct strbuf input = STRBUF_INIT;

@@ -2988,3 +2988,14 @@ int read_loose_object(const char *path,
 		munmap(map, mapsize);
 	return ret;
 }
+
+void free_object_info_contents(struct object_info *object_info)
+{
+	if (!object_info)
+		return;
+	free(object_info->typep);
+	free(object_info->sizep);
+	free(object_info->disk_sizep);
+	free(object_info->delta_base_oid);
+	free(object_info->type_name);
+}

@@ -533,4 +533,7 @@ int for_each_object_in_pack(struct packed_git *p,
 int for_each_packed_object(each_packed_object_fn, void *,
 			   enum for_each_object_flags flags);
 
+/* Free pointers inside of object_info, but not object_info itself */
+void free_object_info_contents(struct object_info *object_info);
+
 #endif /* OBJECT_STORE_LL_H */

@@ -0,0 +1,412 @@
+#!/bin/sh
+
+test_description='git cat-file --batch-command with remote-object-info command'
+
+GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME=main
+export GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME
+
+. ./test-lib.sh
+
+echo_without_newline () {
+    printf '%s' "$*"
+}
+
+strlen () {
+    echo_without_newline "$1" | wc -c | sed -e 's/^ *//'
+}
+
+hello_content="Hello World"
+hello_size=$(strlen "$hello_content")
+hello_oid=$(echo_without_newline "$hello_content" | git hash-object --stdin)
+
+tree_size=$(($(test_oid rawsz) + 13))
+
+commit_message="Initial commit"
+commit_size=$(($(test_oid hexsz) + 137))
+
+tag_header_without_oid="type blob
+tag hellotag
+tagger $GIT_COMMITTER_NAME <$GIT_COMMITTER_EMAIL>"
+tag_header_without_timestamp="object $hello_oid
+$tag_header_without_oid"
+tag_description="This is a tag"
+tag_content="$tag_header_without_timestamp 0 +0000
+
+$tag_description"
+
+tag_oid=$(echo_without_newline "$tag_content" | git hash-object -t tag --stdin -w)
+tag_size=$(strlen "$tag_content")
+
+# This section tests --batch-command with remote-object-info command
+# Since "%(objecttype)" is currently not supported by the command remote-object-info ,
+# the filters are set to "%(objectname) %(objectsize)".
+# Tests with the default filter are used to test the fallback to 'fetch' command
+
+
+# Test --batch-command remote-object-info with 'git://' transport
+
+. "$TEST_DIRECTORY"/lib-git-daemon.sh
+start_git_daemon --export-all --enable=receive-pack
+daemon_parent=$GIT_DAEMON_DOCUMENT_ROOT_PATH/parent
+
+test_expect_success 'create repo to be served by git-daemon' '
+	git init "$daemon_parent" &&
+
+	echo_without_newline "$hello_content" > $daemon_parent/hello &&
+	git -C "$daemon_parent" update-index --add hello &&
+	git -C "$daemon_parent" config transfer.advertiseobjectinfo true
+'
+
+set_transport_variables () {
+	hello_sha1=$(echo_without_newline "$hello_content" | git hash-object --stdin)
+	tree_sha1=$(git -C "$1" write-tree)
+	commit_sha1=$(echo_without_newline "$commit_message" | git -C "$1" commit-tree $tree_sha1)
+	tag_sha1=$(echo_without_newline "$tag_content" | git -C "$1" hash-object -t tag --stdin -w)
+	tag_size=$(strlen "$tag_content")
+}
+
+
+test_expect_success 'batch-command remote-object-info git://' '
+	(
+		set_transport_variables "$daemon_parent" &&
+		cd "$daemon_parent" &&
+
+		echo "$hello_sha1 $hello_size" >expect &&
+		echo "$tree_sha1 $tree_size" >>expect &&
+		echo "$commit_sha1 $commit_size" >>expect &&
+		echo "$tag_sha1 $tag_size" >>expect &&
+		git cat-file --batch-command="%(objectname) %(objectsize)" >actual <<-EOF &&
+		remote-object-info "$GIT_DAEMON_URL/parent" $hello_sha1
+		remote-object-info "$GIT_DAEMON_URL/parent" $tree_sha1
+		remote-object-info "$GIT_DAEMON_URL/parent" $commit_sha1
+		remote-object-info "$GIT_DAEMON_URL/parent" $tag_sha1
+		EOF
+		test_cmp expect actual
+	)
+'
+
+test_expect_success 'batch-command remote-object-info git:// multiple sha1 per line' '
+	(
+		set_transport_variables "$daemon_parent" &&
+		cd "$daemon_parent" &&
+
+		echo "$hello_sha1 $hello_size" >expect &&
+		echo "$tree_sha1 $tree_size" >>expect &&
+		echo "$commit_sha1 $commit_size" >>expect &&
+		echo "$tag_sha1 $tag_size" >>expect &&
+		git cat-file --batch-command="%(objectname) %(objectsize)" >actual <<-EOF &&
+		remote-object-info "$GIT_DAEMON_URL/parent" $hello_sha1 $tree_sha1 $commit_sha1 $tag_sha1
+		EOF
+		test_cmp expect actual
+	)
+'
+
+test_expect_success 'batch-command remote-object-info http:// default filter' '
+	(
+		set_transport_variables "$daemon_parent" &&
+		cd "$daemon_parent" &&
+
+		echo "$hello_sha1 $hello_size" >expect &&
+		echo "$tree_sha1 $tree_size" >>expect &&
+		echo "$commit_sha1 $commit_size" >>expect &&
+		echo "$tag_sha1 $tag_size" >>expect &&
+		GIT_TRACE_PACKET=1 git cat-file --batch-command >actual <<-EOF &&
+		remote-object-info "$GIT_DAEMON_URL/parent" $hello_sha1 $tree_sha1
+		remote-object-info "$GIT_DAEMON_URL/parent" $commit_sha1 $tag_sha1
+		EOF
+		test_cmp expect actual
+	)
+'
+
+test_expect_success 'batch-command --buffer remote-object-info git://' '
+	(
+		set_transport_variables "$daemon_parent" &&
+		cd "$daemon_parent" &&
+
+		echo "$hello_sha1 $hello_size" >expect &&
+		echo "$tree_sha1 $tree_size" >>expect &&
+		echo "$commit_sha1 $commit_size" >>expect &&
+		echo "$tag_sha1 $tag_size" >>expect &&
+		git cat-file --batch-command="%(objectname) %(objectsize)" --buffer >actual <<-EOF &&
+		remote-object-info "$GIT_DAEMON_URL/parent" $hello_sha1 $tree_sha1
+		remote-object-info "$GIT_DAEMON_URL/parent" $commit_sha1 $tag_sha1
+		flush
+		EOF
+		test_cmp expect actual
+	)
+'
+
+stop_git_daemon
+
+# Test --batch-command remote-object-info with 'http://' transport
+
+. "$TEST_DIRECTORY"/lib-httpd.sh
+start_httpd
+
+test_expect_success 'create repo to be served by http:// transport' '
+	git init "$HTTPD_DOCUMENT_ROOT_PATH/http_parent" &&
+	git -C "$HTTPD_DOCUMENT_ROOT_PATH/http_parent" config http.receivepack true &&
+	git -C "$HTTPD_DOCUMENT_ROOT_PATH/http_parent" config transfer.advertiseobjectinfo true &&
+	echo_without_newline "$hello_content" > $HTTPD_DOCUMENT_ROOT_PATH/http_parent/hello &&
+	git -C "$HTTPD_DOCUMENT_ROOT_PATH/http_parent" update-index --add hello
+'
+
+
+test_expect_success 'batch-command remote-object-info http://' '
+	(
+		set_transport_variables "$HTTPD_DOCUMENT_ROOT_PATH/http_parent" &&
+		cd "$HTTPD_DOCUMENT_ROOT_PATH/http_parent" &&
+
+		echo "$hello_sha1 $hello_size" >expect &&
+		echo "$tree_sha1 $tree_size" >>expect &&
+		echo "$commit_sha1 $commit_size" >>expect &&
+		echo "$tag_sha1 $tag_size" >>expect &&
+		git cat-file --batch-command="%(objectname) %(objectsize)" >actual <<-EOF &&
+		remote-object-info "$HTTPD_URL/smart/http_parent" $hello_sha1
+		remote-object-info "$HTTPD_URL/smart/http_parent" $tree_sha1
+		remote-object-info "$HTTPD_URL/smart/http_parent" $commit_sha1
+		remote-object-info "$HTTPD_URL/smart/http_parent" $tag_sha1
+		EOF
+		test_cmp expect actual
+	)
+'
+
+test_expect_success 'batch-command remote-object-info http:// one line' '
+	(
+		set_transport_variables "$HTTPD_DOCUMENT_ROOT_PATH/http_parent" &&
+		cd "$HTTPD_DOCUMENT_ROOT_PATH/http_parent" &&
+
+		echo "$hello_sha1 $hello_size" >expect &&
+		echo "$tree_sha1 $tree_size" >>expect &&
+		echo "$commit_sha1 $commit_size" >>expect &&
+		echo "$tag_sha1 $tag_size" >>expect &&
+		git cat-file --batch-command="%(objectname) %(objectsize)" >actual <<-EOF &&
+		remote-object-info "$HTTPD_URL/smart/http_parent" $hello_sha1 $tree_sha1 $commit_sha1 $tag_sha1
+		EOF
+		test_cmp expect actual
+	)
+'
+
+test_expect_success 'batch-command --buffer remote-object-info http://' '
+	(
+		set_transport_variables "$HTTPD_DOCUMENT_ROOT_PATH/http_parent" &&
+		cd "$HTTPD_DOCUMENT_ROOT_PATH/http_parent" &&
+
+		echo "$hello_sha1 $hello_size" >expect &&
+		echo "$tree_sha1 $tree_size" >>expect &&
+		echo "$commit_sha1 $commit_size" >>expect &&
+		echo "$tag_sha1 $tag_size" >>expect &&
+
+		git cat-file --batch-command="%(objectname) %(objectsize)" --buffer >actual <<-EOF &&
+		remote-object-info "$HTTPD_URL/smart/http_parent" $hello_sha1 $tree_sha1
+		remote-object-info "$HTTPD_URL/smart/http_parent" $commit_sha1 $tag_sha1
+		flush
+		EOF
+		test_cmp expect actual
+	)
+'
+
+test_expect_success 'batch-command remote-object-info http:// default filter' '
+	(
+		set_transport_variables "$HTTPD_DOCUMENT_ROOT_PATH/http_parent" &&
+		cd "$HTTPD_DOCUMENT_ROOT_PATH/http_parent" &&
+
+		echo "$hello_sha1 $hello_size" >expect &&
+		echo "$tree_sha1 $tree_size" >>expect &&
+		echo "$commit_sha1 $commit_size" >>expect &&
+		echo "$tag_sha1 $tag_size" >>expect &&
+
+		git cat-file --batch-command >actual <<-EOF &&
+		remote-object-info "$HTTPD_URL/smart/http_parent" $hello_sha1 $tree_sha1
+		remote-object-info "$HTTPD_URL/smart/http_parent" $commit_sha1 $tag_sha1
+		EOF
+		test_cmp expect actual
+	)
+'
+
+test_expect_success 'remote-object-info fails on unspported filter option (objectsize:disk)' '
+	(
+		set_transport_variables "$HTTPD_DOCUMENT_ROOT_PATH/http_parent" &&
+		cd "$HTTPD_DOCUMENT_ROOT_PATH/http_parent" &&
+
+		test_must_fail git cat-file --batch-command="%(objectsize:disk)" 2>err <<-EOF &&
+		remote-object-info "$HTTPD_URL/smart/http_parent" $hello_sha1
+		EOF
+		test_grep "objectsize:disk is currently not supported with remote-object-info" err
+	)
+'
+
+test_expect_success 'remote-object-info fails on unspported filter option (deltabase)' '
+	(
+		set_transport_variables "$HTTPD_DOCUMENT_ROOT_PATH/http_parent" &&
+		cd "$HTTPD_DOCUMENT_ROOT_PATH/http_parent" &&
+
+		test_must_fail git cat-file --batch-command="%(deltabase)" 2>err <<-EOF &&
+		remote-object-info "$HTTPD_URL/smart/http_parent" $hello_sha1
+		EOF
+		test_grep "deltabase is currently not supported with remote-object-info" err
+	)
+'
+
+test_expect_success 'remote-object-info fails on server with legacy protocol' '
+	(
+		set_transport_variables "$HTTPD_DOCUMENT_ROOT_PATH/http_parent" &&
+		cd "$HTTPD_DOCUMENT_ROOT_PATH/http_parent" &&
+
+		test_must_fail git -c protocol.version=0 cat-file --batch-command="%(objectname) %(objectsize)" 2>err <<-EOF &&
+		remote-object-info "$HTTPD_URL/smart/http_parent" $hello_sha1
+		EOF
+		test_grep "remote-object-info requires protocol v2" err
+	)
+'
+
+test_expect_success 'remote-object-info fails on server with legacy protocol fallback' '
+	(
+		set_transport_variables "$HTTPD_DOCUMENT_ROOT_PATH/http_parent" &&
+		cd "$HTTPD_DOCUMENT_ROOT_PATH/http_parent" &&
+
+		test_must_fail git -c protocol.version=0 cat-file --batch-command 2>err <<-EOF &&
+		remote-object-info "$HTTPD_URL/smart/http_parent" $hello_sha1
+		EOF
+		test_grep "remote-object-info requires protocol v2" err
+	)
+'
+
+test_expect_success 'remote-object-info fails on malformed OID' '
+	(
+		set_transport_variables "$HTTPD_DOCUMENT_ROOT_PATH/http_parent" &&
+		cd "$HTTPD_DOCUMENT_ROOT_PATH/http_parent" &&
+		malformed_object_id="this_id_is_not_valid" &&
+
+		test_must_fail git cat-file --batch-command="%(objectname) %(objectsize)" 2>err <<-EOF &&
+		remote-object-info "$HTTPD_URL/smart/http_parent" $malformed_object_id
+		EOF
+		test_grep "Not a valid object name '$malformed_object_id'" err
+	)
+'
+
+test_expect_success 'remote-object-info fails on malformed OID fallback' '
+	(
+		set_transport_variables "$HTTPD_DOCUMENT_ROOT_PATH/http_parent" &&
+		cd "$HTTPD_DOCUMENT_ROOT_PATH/http_parent" &&
+		malformed_object_id="this_id_is_not_valid" &&
+
+		test_must_fail git cat-file --batch-command 2>err <<-EOF &&
+		remote-object-info "$HTTPD_URL/smart/http_parent" $malformed_object_id
+		EOF
+		test_grep "Not a valid object name '$malformed_object_id'" err
+	)
+'
+
+test_expect_success 'remote-object-info fails on missing OID' '
+	set_transport_variables "$HTTPD_DOCUMENT_ROOT_PATH/http_parent" &&
+	git clone "$HTTPD_DOCUMENT_ROOT_PATH/http_parent" missing_oid_repo &&
+	test_commit -C missing_oid_repo message1 c.txt &&
+	(
+		cd missing_oid_repo &&
+
+		object_id=$(git rev-parse message1:c.txt) &&
+		test_must_fail git cat-file --batch-command="%(objectname) %(objectsize)" 2>err <<-EOF &&
+		remote-object-info "$HTTPD_URL/smart/http_parent" $object_id
+		EOF
+		test_grep "object-info: not our ref $object_id" err
+	)
+'
+
+# shellcheck disable=SC2016
+test_expect_success 'remote-object-info fails on missing OID fallback' '
+	(
+		set_transport_variables "$HTTPD_DOCUMENT_ROOT_PATH/http_parent" &&
+		cd missing_oid_repo &&
+		object_id=$(git rev-parse message1:c.txt) &&
+		test_must_fail git cat-file --batch-command 2>err <<-EOF &&
+		remote-object-info "$HTTPD_URL/smart/http_parent" $object_id
+		EOF
+		test_grep "fatal: object-info: not our ref $object_id" err
+	)
+'
+
+# Test --batch-command remote-object-info with 'file://' transport
+
+# shellcheck disable=SC2016
+test_expect_success 'create repo to be served by file:// transport' '
+	git init server &&
+	git -C server config protocol.version 2 &&
+	git -C server config transfer.advertiseobjectinfo true &&
+	echo_without_newline "$hello_content" > server/hello &&
+	git -C server update-index --add hello
+'
+
+
+test_expect_success 'batch-command remote-object-info file://' '
+	(
+		set_transport_variables "server" &&
+		cd server &&
+
+		echo "$hello_sha1 $hello_size" >expect &&
+		echo "$tree_sha1 $tree_size" >>expect &&
+		echo "$commit_sha1 $commit_size" >>expect &&
+		echo "$tag_sha1 $tag_size" >>expect &&
+		git cat-file --batch-command="%(objectname) %(objectsize)" >actual <<-EOF &&
+		remote-object-info "file://$(pwd)" $hello_sha1
+		remote-object-info "file://$(pwd)" $tree_sha1
+		remote-object-info "file://$(pwd)" $commit_sha1
+		remote-object-info "file://$(pwd)" $tag_sha1
+		EOF
+		test_cmp expect actual
+	)
+'
+
+test_expect_success 'batch-command remote-object-info file:// multiple sha1 per line' '
+	(
+		set_transport_variables "server" &&
+		cd server &&
+
+		echo "$hello_sha1 $hello_size" >expect &&
+		echo "$tree_sha1 $tree_size" >>expect &&
+		echo "$commit_sha1 $commit_size" >>expect &&
+		echo "$tag_sha1 $tag_size" >>expect &&
+		git cat-file --batch-command="%(objectname) %(objectsize)" >actual <<-EOF &&
+		remote-object-info "file://$(pwd)" $hello_sha1 $tree_sha1 $commit_sha1 $tag_sha1
+		EOF
+		test_cmp expect actual
+	)
+'
+
+test_expect_success 'batch-command --buffer remote-object-info file://' '
+	(
+		set_transport_variables "server" &&
+		cd server &&
+
+		echo "$hello_sha1 $hello_size" >expect &&
+		echo "$tree_sha1 $tree_size" >>expect &&
+		echo "$commit_sha1 $commit_size" >>expect &&
+		echo "$tag_sha1 $tag_size" >>expect &&
+		git cat-file --batch-command="%(objectname) %(objectsize)" --buffer >actual <<-EOF &&
+		remote-object-info "file://$(pwd)" $hello_sha1 $tree_sha1
+		remote-object-info "file://$(pwd)" $commit_sha1 $tag_sha1
+		flush
+		EOF
+		test_cmp expect actual
+	)
+'
+
+test_expect_success 'batch-command remote-object-info file:// default filter' '
+	(
+		set_transport_variables "server" &&
+		cd server &&
+
+		echo "$hello_sha1 $hello_size" >expect &&
+		echo "$tree_sha1 $tree_size" >>expect &&
+		echo "$commit_sha1 $commit_size" >>expect &&
+		echo "$tag_sha1 $tag_size" >>expect &&
+
+		git cat-file --batch-command >actual <<-EOF &&
+		remote-object-info "file://$(pwd)" $hello_sha1 $tree_sha1
+		remote-object-info "file://$(pwd)" $commit_sha1 $tag_sha1
+		EOF
+		test_cmp expect actual
+	)
+'
+
+test_done