Remove false-positive data loss claim on region failover

fdbcli/StatusCommand.cpp

@@ -102,6 +102,23 @@ int getNumofNonExcludedMachines(StatusObjectReader statusObjCluster) {
 	return numOfNonExcludedMachines;
 }
 
+bool logEpochsMayBeLosingData(StatusObjectReader statusObjCluster) {
+	if (!statusObjCluster.has("logs")) {
+		return true;
+	}
+
+	bool sawLogEpoch = false;
+	for (StatusObjectReader logEpoch : statusObjCluster.last().get_array()) {
+		sawLogEpoch = true;
+		bool possiblyLosingData = true;
+		if (!logEpoch.get("possibly_losing_data", possiblyLosingData) || possiblyLosingData) {
+			return true;
+		}
+	}
+
+	return !sawLogEpoch;
+}
+
 std::string getDateInfoString(StatusObjectReader statusObj, std::string key) {
 	time_t curTime;
 	if (!statusObj.has(key)) {
@@ -689,16 +706,22 @@ void printStatus(StatusObjectReader statusObj,
 
 						if (dataLoss == -1) {
 							ASSERT_WE_THINK(availLoss == -1);
-							outputString += format(
-							    "\n\n  Warning: the database may have data loss and availability loss. Please restart "
-							    "following tlog interfaces, otherwise storage servers may never be able to catch "
-							    "up.\n");
-							StatusObjectReader logs;
+							const bool possiblyLosingData = logEpochsMayBeLosingData(statusObjCluster);
+							if (possiblyLosingData) {
+								outputString += format(
+								    "\n\n  Warning: the database may have data loss and availability loss. Please "
+								    "restart following tlog interfaces, otherwise storage servers may never be able "
+								    "to catch up.\n");
+							} else {
+								outputString += format(
+								    "\n\n  Warning: the database may have availability loss. The current log state "
+								    "does not indicate data loss.\n");
+							}
 							if (statusObjCluster.has("logs")) {
 								for (StatusObjectReader logEpoch : statusObjCluster.last().get_array()) {
-									bool possiblyLosingData;
-									if (logEpoch.get("possibly_losing_data", possiblyLosingData) &&
-									    !possiblyLosingData) {
+									bool logEpochPossiblyLosingData;
+									if (logEpoch.get("possibly_losing_data", logEpochPossiblyLosingData) &&
+									    !logEpochPossiblyLosingData) {
 										continue;
 									}
 									// Current epoch doesn't have an end version.

fdbcli/fdbcli.cpp

@@ -865,6 +865,8 @@ void LogCommand(std::string line, UID randomID, std::string errMsg) {
 }
 
 struct CLIOptions {
+	static constexpr int DEFERRED_EXIT_CODE = -2;
+
 	std::string program_name;
 	int exit_code = -1;
 
@@ -877,6 +879,7 @@ struct CLIOptions {
 	std::string logGroup;
 	int exit_timeout = 0;
 	Optional<std::string> exec;
+	Optional<std::string> statusJsonFile;
 	bool initialStatusCheck = true;
 	bool cliHints = true;
 	bool cliHistory = true;
@@ -907,12 +910,15 @@ struct CLIOptions {
 
 		while (args.Next()) {
 			int ec = processArg(args);
+			if (ec == DEFERRED_EXIT_CODE) {
+				return;
+			}
 			if (ec != -1) {
 				exit_code = ec;
 				return;
 			}
 		}
-		if (exit_timeout && !exec.present()) {
+		if (exit_timeout && !exec.present() && !statusJsonFile.present()) {
 			fprintf(stderr, "ERROR: --timeout may only be specified with --exec\n");
 			exit_code = FDB_EXIT_ERROR;
 			return;
@@ -1018,7 +1024,8 @@ struct CLIOptions {
 			printProgramUsage(program_name.c_str());
 			return 0;
 		case OPT_STATUS_FROM_JSON:
-			return printStatusFromJSON(args.OptionArg());
+			statusJsonFile = args.OptionArg();
+			return DEFERRED_EXIT_CODE;
 		case OPT_TRACE_FORMAT:
 			if (!validateTraceFormat(args.OptionArg())) {
 				fprintf(stderr, "WARNING: Unrecognized trace format `%s'\n", args.OptionArg());
@@ -2136,6 +2143,21 @@ int main(int argc, char** argv) {
 		return 1;
 	}
 
+	if (opt.statusJsonFile.present()) {
+		try {
+			API->selectApiVersion(opt.apiVersion);
+			if (opt.useFutureProtocolVersion) {
+				API->useFutureProtocolVersion();
+			}
+			API->setupNetwork();
+			opt.setupKnobs();
+			return printStatusFromJSON(opt.statusJsonFile.get());
+		} catch (Error& e) {
+			fprintf(stderr, "ERROR: %s (%d)\n", e.what(), e.code());
+			return 1;
+		}
+	}
+
 	if (opt.debugTLS) {
 		// Backdoor into NativeAPI's tlsConfig, which is where the above network option settings ended up.
 		extern TLSConfig tlsConfig;

fdbcli/tests/fdbcli_tests.py

@@ -471,6 +471,64 @@ def get_value_from_status_json(retry, *args):
     return result
 
 
+def status_json_file_region_failover_message():
+    status_json = {
+        "client": {
+            "cluster_file": {"path": "fdb.cluster", "up_to_date": True},
+            "coordinators": {"coordinators": [], "quorum_reachable": True},
+            "database_status": {"available": True, "healthy": False},
+            "messages": [],
+            "timestamp": 1417807090,
+        },
+        "cluster": {
+            "configuration": {
+                "redundancy_mode": "three_data_hall",
+                "storage_engine": "ssd-2",
+                "coordinators_count": 3,
+                "excluded_servers": [],
+            },
+            "data": {"state": {"name": "healthy", "healthy": True}},
+            "fault_tolerance": {
+                "max_zone_failures_without_losing_availability": -1,
+                "max_zone_failures_without_losing_data": -1,
+            },
+            "logs": [
+                {
+                    "epoch": 1,
+                    "current": True,
+                    "begin_version": 1,
+                    "possibly_losing_data": False,
+                    "log_interfaces": [
+                        {
+                            "id": "aaaaaaaaaaaaaaaa",
+                            "healthy": False,
+                            "address": "1.1.1.1:4500",
+                        }
+                    ],
+                }
+            ],
+            "machines": {},
+            "processes": {},
+        },
+    }
+
+    with tempfile.NamedTemporaryFile(mode="w", suffix=".json") as status_file:
+        json.dump(status_json, status_file)
+        status_file.flush()
+        result = subprocess.run(
+            [command_template[0], "--status-from-json", status_file.name],
+            stdout=subprocess.PIPE,
+            stderr=subprocess.PIPE,
+            env=fdbcli_env,
+        )
+
+    stdout = result.stdout.decode("utf-8")
+    stderr = result.stderr.decode("utf-8")
+    assert result.returncode == 0, stderr
+    assert "Warning: the database may have availability loss." in stdout
+    assert "may have data loss" not in stdout
+
+
 @enable_logging()
 def consistencycheck(logger):
     consistency_check_on_output = "ConsistencyCheck is on"
@@ -948,6 +1006,7 @@ def tls_address_suffix():
         versionepoch()
         integer_options()
         tls_address_suffix()
+        status_json_file_region_failover_message()
         # TODO: fix the issue when running through the external client
         # quota()
         idempotency_ids()