refactor zen command return value handling (#487)

- Improvement: Use consistent language for command line argument parsing errors
- Improvement: Changed zen command parsing errors to output help first and error last to make it easier to spot the error
- Improvement: Refactor zen command return codes to conform to valid Linux range (0-255)

        kSuccess     = 0,
        kOtherError  = 1,
        kBadInput    = 2,

        kOutOfMemory = 16,
        kOutOfDisk   = 17,

        kAssertError = 70,
        
        kHttpOtherClientError = 80,
        kHttpCantConnectError = 81,
        kHttpNotFound         = 66,  // NotFound(404)
        kHttpUnauthorized     = 77,  // Unauthorized(401),
        kHttpSLLError         = 82,
        kHttpForbidden        = 83,  // Forbidden(403)
        kHttpTimeout          = 84,  // RequestTimeout(408)
        kHttpConflict         = 85,  // Conflict(409)
        kHttpNoHost           = 86,
        
        kHttpOtherServerError	   = 90,
        kHttpInternalServerError = 91,  // InternalServerError(500)
        kHttpServiceUnavailable  = 69,  // ServiceUnavailable(503)
        kHttpBadGateway          = 92,  // BadGateway(502)
        kHttpGatewayTimeout      = 93,  // GatewayTimeout(504)

1 files changed, 109 insertions, 166 deletions

diff --git a/src/zen/cmds/projectstore_cmd.cpp b/src/zen/cmds/projectstore_cmd.cpp
index 5f0f52f7c..11c915e9a 100644
--- a/src/zen/cmds/projectstore_cmd.cpp
+++ b/src/zen/cmds/projectstore_cmd.cpp
@@ -149,16 +149,6 @@ namespace {
 		}
 	}
 
-	class AsyncJobError : public std::runtime_error
-	{
-	public:
-		using _Mybase = runtime_error;
-
-		AsyncJobError(const std::string& Message, int ReturnCode) : _Mybase(Message), m_ReturnCode(ReturnCode) {}
-
-		const int m_ReturnCode = 0;
-	};
-
 	void ExecuteAsyncOperation(HttpClient& Http, std::string_view Url, IoBuffer&& Payload, bool PlainProgress)
 	{
 		signal(SIGINT, SignalCallbackHandler);
@@ -265,11 +255,11 @@ namespace {
 						int				 ReturnCode	 = StatusObject["ReturnCode"].AsInt32(-1);
 						if (!AbortReason.empty())
 						{
-							throw AsyncJobError(std::string(AbortReason), ReturnCode);
+							throw ErrorWithReturnCode(std::string(AbortReason), ReturnCode);
 						}
 						else
 						{
-							throw AsyncJobError("Aborted", ReturnCode);
+							throw ErrorWithReturnCode("Aborted", ReturnCode);
 						}
 						break;
 					}
@@ -564,21 +554,21 @@ DropProjectCommand::~DropProjectCommand()
 {
 }
 
-int
+void
 DropProjectCommand::Run(const ZenCliOptions& GlobalOptions, int argc, char** argv)
 {
 	ZEN_UNUSED(GlobalOptions);
 
 	if (!ParseOptions(argc, argv))
 	{
-		return 0;
+		return;
 	}
 
 	m_HostName = ResolveTargetHostSpec(m_HostName);
 
 	if (m_HostName.empty())
 	{
-		throw OptionParseException("unable to resolve server specification");
+		throw OptionParseException("Unable to resolve server specification", m_Options.help());
 	}
 
 	HttpClient Http(m_HostName);
@@ -586,7 +576,7 @@ DropProjectCommand::Run(const ZenCliOptions& GlobalOptions, int argc, char** arg
 	m_ProjectName = ResolveProject(Http, m_ProjectName);
 	if (m_ProjectName.empty())
 	{
-		return 1;
+		throw std::runtime_error(fmt::format("Can't find project '{}'", m_ProjectName));
 	}
 
 	if (m_OplogName.empty())
@@ -605,7 +595,6 @@ DropProjectCommand::Run(const ZenCliOptions& GlobalOptions, int argc, char** arg
 			else
 			{
 				Result.ThrowError("delete project failed"sv);
-				return 1;
 			}
 		}
 	}
@@ -614,7 +603,7 @@ DropProjectCommand::Run(const ZenCliOptions& GlobalOptions, int argc, char** arg
 		m_OplogName = ResolveOplog(Http, m_ProjectName, m_OplogName);
 		if (m_OplogName.empty())
 		{
-			return 1;
+			throw std::runtime_error(fmt::format("Can't find oplog in project '{}'", m_OplogName, m_ProjectName));
 		}
 		if (m_DryRun)
 		{
@@ -633,12 +622,9 @@ DropProjectCommand::Run(const ZenCliOptions& GlobalOptions, int argc, char** arg
 			else
 			{
 				Result.ThrowError("delete oplog failed"sv);
-				return 1;
 			}
 		}
 	}
-
-	return 0;
 }
 
 ///////////////////////////////////////
@@ -657,26 +643,26 @@ ProjectInfoCommand::~ProjectInfoCommand()
 {
 }
 
-int
+void
 ProjectInfoCommand::Run(const ZenCliOptions& GlobalOptions, int argc, char** argv)
 {
 	ZEN_UNUSED(GlobalOptions);
 
 	if (!ParseOptions(argc, argv))
 	{
-		return 0;
+		return;
 	}
 
 	m_HostName = ResolveTargetHostSpec(m_HostName);
 
 	if (m_HostName.empty())
 	{
-		throw OptionParseException("unable to resolve server specification");
+		throw OptionParseException("Unable to resolve server specification", m_Options.help());
 	}
 
 	if (!m_OplogName.empty() && m_ProjectName.empty())
 	{
-		throw OptionParseException("an oplog can't be specified without also specifying a project");
+		throw OptionParseException("'--project' is required", m_Options.help());
 	}
 
 	HttpClient Http(m_HostName);
@@ -692,7 +678,7 @@ ProjectInfoCommand::Run(const ZenCliOptions& GlobalOptions, int argc, char** arg
 		m_ProjectName = ResolveProject(Http, m_ProjectName);
 		if (m_ProjectName.empty())
 		{
-			return 1;
+			throw std::runtime_error("Unable to resolve project");
 		}
 
 		Url = fmt::format("/prj/{}", m_ProjectName);
@@ -703,13 +689,13 @@ ProjectInfoCommand::Run(const ZenCliOptions& GlobalOptions, int argc, char** arg
 		m_ProjectName = ResolveProject(Http, m_ProjectName);
 		if (m_ProjectName.empty())
 		{
-			return 1;
+			throw std::runtime_error("Unable to resolve project");
 		}
 
 		m_OplogName = ResolveOplog(Http, m_ProjectName, m_OplogName);
 		if (m_OplogName.empty())
 		{
-			return 1;
+			throw std::runtime_error("Unable to resolve oplog");
 		}
 
 		Url = fmt::format("/prj/{}/oplog/{}", m_ProjectName, m_OplogName);
@@ -719,12 +705,10 @@ ProjectInfoCommand::Run(const ZenCliOptions& GlobalOptions, int argc, char** arg
 	if (HttpClient::Response Result = Http.Get(Url, HttpClient::Accept(ZenContentType::kJSON)))
 	{
 		ZEN_CONSOLE("{}", Result.ToText());
-		return 0;
 	}
 	else
 	{
 		Result.ThrowError("failed to fetch info"sv);
-		return 1;
 	}
 }
 
@@ -745,7 +729,7 @@ CreateProjectCommand::CreateProjectCommand()
 
 CreateProjectCommand::~CreateProjectCommand() = default;
 
-int
+void
 CreateProjectCommand::Run(const ZenCliOptions& GlobalOptions, int argc, char** argv)
 {
 	ZEN_UNUSED(GlobalOptions);
@@ -754,19 +738,19 @@ CreateProjectCommand::Run(const ZenCliOptions& GlobalOptions, int argc, char** a
 
 	if (!ParseOptions(argc, argv))
 	{
-		return 0;
+		return;
 	}
 
 	m_HostName = ResolveTargetHostSpec(m_HostName);
 
 	if (m_HostName.empty())
 	{
-		throw OptionParseException("unable to resolve server specification");
+		throw OptionParseException("Unable to resolve server specification", m_Options.help());
 	}
 
 	if (m_ProjectId.empty())
 	{
-		throw OptionParseException("Project name must be given");
+		throw OptionParseException("'--project' is required", m_Options.help());
 	}
 
 	HttpClient Http(m_HostName);
@@ -777,8 +761,7 @@ CreateProjectCommand::Run(const ZenCliOptions& GlobalOptions, int argc, char** a
 	{
 		if (HttpClient::Response Result = Http.Get(Url, HttpClient::Accept(ZenContentType::kJSON)))
 		{
-			ZEN_CONSOLE_ERROR("Project already exists.\n{}", Result.ToText());
-			return 1;
+			throw std::runtime_error(fmt::format("Project already exists.\n{}", Result.ToText()));
 		}
 	}
 
@@ -793,12 +776,10 @@ CreateProjectCommand::Run(const ZenCliOptions& GlobalOptions, int argc, char** a
 													: Http.Post(Url, Payload, HttpClient::Accept(ZenContentType::kText)))
 	{
 		ZEN_CONSOLE("{}", Result);
-		return 0;
 	}
 	else
 	{
 		Result.ThrowError("failed to create project"sv);
-		return 1;
 	}
 }
 
@@ -817,7 +798,7 @@ CreateOplogCommand::CreateOplogCommand()
 
 CreateOplogCommand::~CreateOplogCommand() = default;
 
-int
+void
 CreateOplogCommand::Run(const ZenCliOptions& GlobalOptions, int argc, char** argv)
 {
 	ZEN_UNUSED(GlobalOptions);
@@ -826,31 +807,31 @@ CreateOplogCommand::Run(const ZenCliOptions& GlobalOptions, int argc, char** arg
 
 	if (!ParseOptions(argc, argv))
 	{
-		return 0;
+		return;
 	}
 
 	m_HostName = ResolveTargetHostSpec(m_HostName);
 
 	if (m_HostName.empty())
 	{
-		throw OptionParseException("unable to resolve server specification");
+		throw OptionParseException("Unable to resolve server specification", m_Options.help());
 	}
 
 	if (m_ProjectId.empty())
 	{
-		throw OptionParseException("project name must be specified");
+		throw OptionParseException("'--project' is required", m_Options.help());
 	}
 
 	HttpClient Http(m_HostName);
 	m_ProjectId = ResolveProject(Http, m_ProjectId);
 	if (m_ProjectId.empty())
 	{
-		return 1;
+		throw std::runtime_error("Project can not be found");
 	}
 
 	if (m_OplogId.empty())
 	{
-		throw OptionParseException("oplog name must be specified");
+		throw OptionParseException("'--oplog' is required", m_Options.help());
 	}
 
 	std::string Url = fmt::format("/prj/{}/oplog/{}", m_ProjectId, m_OplogId);
@@ -858,8 +839,7 @@ CreateOplogCommand::Run(const ZenCliOptions& GlobalOptions, int argc, char** arg
 	{
 		if (HttpClient::Response Result = Http.Get(Url, HttpClient::Accept(ZenContentType::kJSON)))
 		{
-			ZEN_CONSOLE("Oplog already exists.\n{}", Result.ToText());
-			return 1;
+			throw std::runtime_error(fmt::format("Oplog already exists.\n{}", Result.ToText()));
 		}
 	}
 
@@ -873,12 +853,10 @@ CreateOplogCommand::Run(const ZenCliOptions& GlobalOptions, int argc, char** arg
 													: Http.Post(Url, OplogPayload, HttpClient::Accept(ZenContentType::kText)))
 	{
 		ZEN_CONSOLE("{}", Result);
-		return 0;
 	}
 	else
 	{
 		Result.ThrowError("failed to create oplog"sv);
-		return 1;
 	}
 }
 
@@ -1014,7 +992,7 @@ ExportOplogCommand::~ExportOplogCommand()
 {
 }
 
-int
+void
 ExportOplogCommand::Run(const ZenCliOptions& GlobalOptions, int argc, char** argv)
 {
 	using namespace std::literals;
@@ -1023,32 +1001,32 @@ ExportOplogCommand::Run(const ZenCliOptions& GlobalOptions, int argc, char** arg
 
 	if (!ParseOptions(argc, argv))
 	{
-		return 0;
+		return;
 	}
 
 	m_HostName = ResolveTargetHostSpec(m_HostName);
 
 	if (m_HostName.empty())
 	{
-		throw OptionParseException("unable to resolve server specification");
+		throw OptionParseException("Unable to resolve server specification", m_Options.help());
 	}
 
 	if (m_ProjectName.empty())
 	{
-		throw OptionParseException("project name must be specified");
+		throw OptionParseException("'--project' is required", m_Options.help());
 	}
 
 	HttpClient Http(m_HostName);
 	m_ProjectName = ResolveProject(Http, m_ProjectName);
 	if (m_ProjectName.empty())
 	{
-		return 1;
+		throw std::runtime_error("Project can not be found");
 	}
 
 	m_OplogName = ResolveOplog(Http, m_ProjectName, m_OplogName);
 	if (m_OplogName.empty())
 	{
-		return 1;
+		throw std::runtime_error("Oplog can not be found");
 	}
 
 	size_t TargetCount = 0;
@@ -1060,19 +1038,23 @@ ExportOplogCommand::Run(const ZenCliOptions& GlobalOptions, int argc, char** arg
 	{
 		if (TargetCount == 0)
 		{
-			throw OptionParseException("an export target must be specified");
+			throw OptionParseException("'--cloud', '--builds', '--zen' or '--file' is required", m_Options.help());
 		}
 		else
 		{
-			throw OptionParseException("a single export target must be specified");
+			throw OptionParseException("'--cloud', '--builds', '--zen' or '--file' are conflicting", m_Options.help());
 		}
 	}
 
 	if (!m_CloudUrl.empty())
 	{
-		if (m_JupiterNamespace.empty() || m_JupiterBucket.empty())
+		if (m_JupiterNamespace.empty())
 		{
-			throw OptionParseException("Options for cloud target are missing");
+			throw OptionParseException("'--namespace' is required", m_Options.help());
+		}
+		if (m_JupiterBucket.empty())
+		{
+			throw OptionParseException("'--bucket' is required", m_Options.help());
 		}
 		if (m_CloudKey.empty())
 		{
@@ -1087,19 +1069,21 @@ ExportOplogCommand::Run(const ZenCliOptions& GlobalOptions, int argc, char** arg
 	{
 		if (m_JupiterNamespace.empty())
 		{
-			throw OptionParseException("Namespace for builds target it missing");
+			throw OptionParseException("'--namespace' is required", m_Options.help());
 		}
 		if (m_JupiterNamespace.empty() || m_JupiterBucket.empty())
 		{
-			throw OptionParseException("Bucket for builds target it missing");
+			throw OptionParseException("'--bucket' is required", m_Options.help());
 		}
 		if (m_BuildsMetadataPath.empty() && m_BuildsMetadata.empty())
 		{
-			throw OptionParseException("Options for builds target metadata are missing");
+			throw OptionParseException("'--metadata' or --'metadata-path' is required", m_Options.help());
 		}
 		if (!m_BuildsMetadataPath.empty() && !m_BuildsMetadata.empty())
 		{
-			throw OptionParseException("Conflicting options for builds target metadata");
+			throw OptionParseException(
+				fmt::format("'--metadata' ('{}') conflicts with --'metadata-path' ('{}')", m_BuildsMetadata, m_BuildsMetadataPath),
+				m_Options.help());
 		}
 		if (m_BuildsId.empty())
 		{
@@ -1141,7 +1125,6 @@ ExportOplogCommand::Run(const ZenCliOptions& GlobalOptions, int argc, char** arg
 				if (!Result)
 				{
 					Result.ThrowError("failed deleting existing zen remote oplog"sv);
-					return 1;
 				}
 				CreateOplog = true;
 			}
@@ -1153,7 +1136,6 @@ ExportOplogCommand::Run(const ZenCliOptions& GlobalOptions, int argc, char** arg
 		else
 		{
 			Result.ThrowError("failed checking zen remote oplog"sv);
-			return 1;
 		}
 
 		if (CreateOplog)
@@ -1162,7 +1144,6 @@ ExportOplogCommand::Run(const ZenCliOptions& GlobalOptions, int argc, char** arg
 			if (HttpClient::Response Result = TargetHttp.Post(Url); !Result)
 			{
 				Result.ThrowError("failed creating zen remote oplog"sv);
-				return 1;
 			}
 		}
 	}
@@ -1341,36 +1322,24 @@ ExportOplogCommand::Run(const ZenCliOptions& GlobalOptions, int argc, char** arg
 
 	ZEN_CONSOLE("Saving oplog '{}/{}' from '{}' to {}", m_ProjectName, m_OplogName, m_HostName, TargetDescription);
 
-	try
+	if (m_Async)
 	{
-		if (m_Async)
+		if (HttpClient::Response Result = Http.Post(fmt::format("/prj/{}/oplog/{}/rpc", m_ProjectName, m_OplogName),
+													std::move(Payload),
+													HttpClient::Accept(ZenContentType::kJSON));
+			Result)
 		{
-			if (HttpClient::Response Result = Http.Post(fmt::format("/prj/{}/oplog/{}/rpc", m_ProjectName, m_OplogName),
-														std::move(Payload),
-														HttpClient::Accept(ZenContentType::kJSON));
-				Result)
-			{
-				ZEN_CONSOLE("{}", Result.ToText());
-			}
-			else
-			{
-				Result.ThrowError("failed requesting loading oplog export"sv);
-			}
+			ZEN_CONSOLE("{}", Result.ToText());
 		}
 		else
 		{
-			ExecuteAsyncOperation(Http,
-								  fmt::format("/prj/{}/oplog/{}/rpc", m_ProjectName, m_OplogName),
-								  std::move(Payload),
-								  m_PlainProgress);
+			Result.ThrowError("failed requesting loading oplog export"sv);
 		}
 	}
-	catch (const AsyncJobError& Ex)
+	else
 	{
-		ZEN_CONSOLE_ERROR("Oplog export failed: '{}'", Ex.what());
-		return Ex.m_ReturnCode;
+		ExecuteAsyncOperation(Http, fmt::format("/prj/{}/oplog/{}/rpc", m_ProjectName, m_OplogName), std::move(Payload), m_PlainProgress);
 	}
-	return 0;
 }
 
 ////////////////////////////
@@ -1462,7 +1431,7 @@ ImportOplogCommand::~ImportOplogCommand()
 {
 }
 
-int
+void
 ImportOplogCommand::Run(const ZenCliOptions& GlobalOptions, int argc, char** argv)
 {
 	using namespace std::literals;
@@ -1471,31 +1440,31 @@ ImportOplogCommand::Run(const ZenCliOptions& GlobalOptions, int argc, char** arg
 
 	if (!ParseOptions(argc, argv))
 	{
-		return 0;
+		return;
 	}
 
 	m_HostName = ResolveTargetHostSpec(m_HostName);
 
 	if (m_HostName.empty())
 	{
-		throw OptionParseException("unable to resolve server specification");
+		throw OptionParseException("Unable to resolve server specification", m_Options.help());
 	}
 
 	if (m_ProjectName.empty())
 	{
-		throw OptionParseException("Project name must be given");
+		throw OptionParseException("'--project' is required", m_Options.help());
 	}
 
 	if (m_OplogName.empty())
 	{
-		throw OptionParseException("Oplog name must be given");
+		throw OptionParseException("'--oplog' is required", m_Options.help());
 	}
 
 	HttpClient Http(m_HostName);
 	m_ProjectName = ResolveProject(Http, m_ProjectName);
 	if (m_ProjectName.empty())
 	{
-		return 1;
+		throw std::runtime_error("Project can not be found");
 	}
 
 	size_t TargetCount = 0;
@@ -1503,20 +1472,24 @@ ImportOplogCommand::Run(const ZenCliOptions& GlobalOptions, int argc, char** arg
 	TargetCount += m_BuildsUrl.empty() ? 0 : 1;
 	TargetCount += m_ZenUrl.empty() ? 0 : 1;
 	TargetCount += m_FileDirectoryPath.empty() ? 0 : 1;
-	if (TargetCount != 1)
+	if (TargetCount == 0)
 	{
-		throw OptionParseException("Provide one source only");
+		throw OptionParseException("'--cloud', '--builds', '--zen' or '--file' is required", m_Options.help());
+	}
+	else if (TargetCount > 1)
+	{
+		throw OptionParseException("'--cloud', '--builds', '--zen' or '--file' are conflicting", m_Options.help());
 	}
 
 	if (!m_CloudUrl.empty())
 	{
 		if (m_JupiterNamespace.empty())
 		{
-			throw OptionParseException("Namespace option for cloud source is missing");
+			throw OptionParseException("--'namespace' is required", m_Options.help());
 		}
 		if (m_JupiterBucket.empty())
 		{
-			throw OptionParseException("Bucket option for cloud source is missing");
+			throw OptionParseException("--'bucket' is required", m_Options.help());
 		}
 		if (m_CloudKey.empty())
 		{
@@ -1531,15 +1504,15 @@ ImportOplogCommand::Run(const ZenCliOptions& GlobalOptions, int argc, char** arg
 	{
 		if (m_JupiterNamespace.empty())
 		{
-			throw OptionParseException("Namespace option for builds source is missing");
+			throw OptionParseException("'--namespace' is required", m_Options.help());
 		}
 		if (m_JupiterBucket.empty())
 		{
-			throw OptionParseException("Bucket option for builds source is missing");
+			throw OptionParseException("'--bucket' is required", m_Options.help());
 		}
 		if (m_BuildsId.empty())
 		{
-			throw OptionParseException("Build id option for builds source is missing");
+			throw OptionParseException("'--build-id' is required", m_Options.help());
 		}
 	}
 
@@ -1577,7 +1550,6 @@ ImportOplogCommand::Run(const ZenCliOptions& GlobalOptions, int argc, char** arg
 	else if (!IsHttpSuccessCode(Result.StatusCode))
 	{
 		Result.ThrowError("failed checking oplog"sv);
-		return 1;
 	}
 
 	if (CreateOplog)
@@ -1591,7 +1563,6 @@ ImportOplogCommand::Run(const ZenCliOptions& GlobalOptions, int argc, char** arg
 		if (HttpClient::Response Result = Http.Post(Url, OplogPayload); !Result)
 		{
 			Result.ThrowError("failed creating oplog"sv);
-			return 1;
 		}
 	}
 
@@ -1688,36 +1659,24 @@ ImportOplogCommand::Run(const ZenCliOptions& GlobalOptions, int argc, char** arg
 
 	ZEN_CONSOLE("Loading oplog '{}/{}' from '{}' to {}", m_ProjectName, m_OplogName, SourceDescription, m_HostName);
 
-	try
+	if (m_Async)
 	{
-		if (m_Async)
+		if (HttpClient::Response Result = Http.Post(fmt::format("/prj/{}/oplog/{}/rpc", m_ProjectName, m_OplogName),
+													std::move(Payload),
+													HttpClient::Accept(ZenContentType::kJSON));
+			Result)
 		{
-			if (HttpClient::Response Result = Http.Post(fmt::format("/prj/{}/oplog/{}/rpc", m_ProjectName, m_OplogName),
-														std::move(Payload),
-														HttpClient::Accept(ZenContentType::kJSON));
-				Result)
-			{
-				ZEN_CONSOLE("{}", Result.ToText());
-			}
-			else
-			{
-				Result.ThrowError("failed requesting loading oplog import"sv);
-			}
+			ZEN_CONSOLE("{}", Result.ToText());
 		}
 		else
 		{
-			ExecuteAsyncOperation(Http,
-								  fmt::format("/prj/{}/oplog/{}/rpc", m_ProjectName, m_OplogName),
-								  std::move(Payload),
-								  m_PlainProgress);
+			Result.ThrowError("failed requesting loading oplog import"sv);
 		}
 	}
-	catch (const AsyncJobError& Ex)
+	else
 	{
-		ZEN_CONSOLE_ERROR("Oplog export failed: '{}'", Ex.what());
-		return Ex.m_ReturnCode;
+		ExecuteAsyncOperation(Http, fmt::format("/prj/{}/oplog/{}/rpc", m_ProjectName, m_OplogName), std::move(Payload), m_PlainProgress);
 	}
-	return 0;
 }
 
 ////////////////////////////
@@ -1736,7 +1695,7 @@ SnapshotOplogCommand::~SnapshotOplogCommand()
 {
 }
 
-int
+void
 SnapshotOplogCommand::Run(const ZenCliOptions& GlobalOptions, int argc, char** argv)
 {
 	using namespace std::literals;
@@ -1745,34 +1704,33 @@ SnapshotOplogCommand::Run(const ZenCliOptions& GlobalOptions, int argc, char** a
 
 	if (!ParseOptions(argc, argv))
 	{
-		return 0;
+		return;
 	}
 
 	m_HostName = ResolveTargetHostSpec(m_HostName);
 
 	if (m_HostName.empty())
 	{
-		throw OptionParseException("unable to resolve server specification");
+		throw OptionParseException("Unable to resolve server specification", m_Options.help());
 	}
 
 	HttpClient Http(m_HostName);
 
 	if (m_ProjectName.empty())
 	{
-		throw OptionParseException("Project name must be given");
-		return 1;
+		throw OptionParseException("'--project' is required", m_Options.help());
 	}
 
 	m_ProjectName = ResolveProject(Http, m_ProjectName);
 	if (m_ProjectName.empty())
 	{
-		return 1;
+		throw std::runtime_error("Project can not be found");
 	}
 
 	m_OplogName = ResolveOplog(Http, m_ProjectName, m_OplogName);
 	if (m_OplogName.empty())
 	{
-		return 1;
+		throw std::runtime_error("Oplog can not be found");
 	}
 
 	IoBuffer Payload = MakeCbObjectPayload([&](CbObjectWriter& Writer) { Writer.AddString("method"sv, "snapshot"sv); });
@@ -1782,12 +1740,10 @@ SnapshotOplogCommand::Run(const ZenCliOptions& GlobalOptions, int argc, char** a
 			Http.Post(fmt::format("/prj/{}/oplog/{}/rpc", m_ProjectName, m_OplogName), Payload, HttpClient::Accept(ZenContentType::kJSON)))
 	{
 		ZEN_CONSOLE("{}", Result);
-		return 0;
 	}
 	else
 	{
 		Result.ThrowError("failed to create project"sv);
-		return 1;
 	}
 }
 
@@ -1803,33 +1759,31 @@ ProjectStatsCommand::~ProjectStatsCommand()
 {
 }
 
-int
+void
 ProjectStatsCommand::Run(const ZenCliOptions& GlobalOptions, int argc, char** argv)
 {
 	ZEN_UNUSED(GlobalOptions);
 
 	if (!ParseOptions(argc, argv))
 	{
-		return 0;
+		return;
 	}
 
 	m_HostName = ResolveTargetHostSpec(m_HostName);
 
 	if (m_HostName.empty())
 	{
-		throw OptionParseException("unable to resolve server specification");
+		throw OptionParseException("Unable to resolve server specification", m_Options.help());
 	}
 
 	HttpClient Http(m_HostName);
 	if (HttpClient::Response Result = Http.Get("/stats/prj", HttpClient::Accept(ZenContentType::kJSON)))
 	{
 		ZEN_CONSOLE("{}", Result.ToText());
-		return 0;
 	}
 	else
 	{
 		Result.ThrowError("failed to get project stats"sv);
-		return 1;
 	}
 }
 
@@ -1857,21 +1811,21 @@ ProjectOpDetailsCommand::~ProjectOpDetailsCommand()
 {
 }
 
-int
+void
 ProjectOpDetailsCommand::Run(const ZenCliOptions& GlobalOptions, int argc, char** argv)
 {
 	ZEN_UNUSED(GlobalOptions);
 
 	if (!ParseOptions(argc, argv))
 	{
-		return 0;
+		return;
 	}
 
 	m_HostName = ResolveTargetHostSpec(m_HostName);
 
 	if (m_HostName.empty())
 	{
-		throw OptionParseException("unable to resolve server specification");
+		throw OptionParseException("Unable to resolve server specification", m_Options.help());
 	}
 
 	HttpClient Http(m_HostName);
@@ -1879,13 +1833,13 @@ ProjectOpDetailsCommand::Run(const ZenCliOptions& GlobalOptions, int argc, char*
 	m_ProjectName = ResolveProject(Http, m_ProjectName);
 	if (m_ProjectName.empty())
 	{
-		return 1;
+		throw std::runtime_error("Project can not be found");
 	}
 
 	m_OplogName = ResolveOplog(Http, m_ProjectName, m_OplogName);
 	if (m_OplogName.empty())
 	{
-		return 1;
+		throw std::runtime_error("Oplog can not be found");
 	}
 
 	ExtendableStringBuilder<128> Url;
@@ -1915,12 +1869,10 @@ ProjectOpDetailsCommand::Run(const ZenCliOptions& GlobalOptions, int argc, char*
 					  {"csv", m_CSV ? "true" : "false"}}))
 	{
 		ZEN_CONSOLE("{}", Result.ToText());
-		return 0;
 	}
 	else
 	{
 		Result.ThrowError("failed to get project details"sv);
-		return 1;
 	}
 }
 
@@ -1974,21 +1926,21 @@ OplogMirrorCommand::~OplogMirrorCommand()
 {
 }
 
-int
+void
 OplogMirrorCommand::Run(const ZenCliOptions& GlobalOptions, int argc, char** argv)
 {
 	ZEN_UNUSED(GlobalOptions);
 
 	if (!ParseOptions(argc, argv))
 	{
-		return 0;
+		return;
 	}
 
 	m_HostName = ResolveTargetHostSpec(m_HostName);
 
 	if (m_HostName.empty())
 	{
-		throw OptionParseException("unable to resolve server specification");
+		throw OptionParseException("Unable to resolve server specification", m_Options.help());
 	}
 
 	HttpClient Http(m_HostName);
@@ -1996,18 +1948,18 @@ OplogMirrorCommand::Run(const ZenCliOptions& GlobalOptions, int argc, char** arg
 	m_ProjectName = ResolveProject(Http, m_ProjectName);
 	if (m_ProjectName.empty())
 	{
-		return 1;
+		throw std::runtime_error("Project can not be found");
 	}
 
 	m_OplogName = ResolveOplog(Http, m_ProjectName, m_OplogName);
 	if (m_OplogName.empty())
 	{
-		return 1;
+		throw std::runtime_error("Oplog can not be found");
 	}
 
 	if (m_MirrorRootPath.empty())
 	{
-		throw OptionParseException("a target path must be specified");
+		throw OptionParseException("'--target' is required", m_Options.help());
 	}
 
 	Oid ChunkIdFilter = Oid::Zero;
@@ -2016,7 +1968,7 @@ OplogMirrorCommand::Run(const ZenCliOptions& GlobalOptions, int argc, char** arg
 		ChunkIdFilter = Oid::TryFromHexString(m_ChunkIdFilter);
 		if (ChunkIdFilter == Oid::Zero)
 		{
-			throw OptionParseException("chunkid must be an Oid hex string");
+			throw OptionParseException(fmt::format("'--chunk' ('{}') is malformed", m_ChunkIdFilter), m_Options.help());
 		}
 	}
 
@@ -2206,25 +2158,20 @@ OplogMirrorCommand::Run(const ZenCliOptions& GlobalOptions, int argc, char** arg
 
 			if (AbortFlag)
 			{
-				// Error has already been reported by async code
-				return 1;
+				throw std::runtime_error("Failed top mirror oplog");
 			}
 		}
 		else
 		{
-			ZEN_CONSOLE_ERROR("Unknown format response to oplog entries request");
+			throw std::runtime_error("Unknown format response to oplog entries request");
 		}
 	}
 	else
 	{
 		Response.ThrowError("oplog entries fetch failed");
-
-		return 1;
 	}
 
 	ZEN_CONSOLE("mirrored {} files from {} oplog entries successfully", FileCount.load(), OplogEntryCount);
-
-	return 0;
 }
 
 ////////////////////////////
@@ -2244,21 +2191,21 @@ OplogValidateCommand::~OplogValidateCommand()
 {
 }
 
-int
+void
 OplogValidateCommand::Run(const ZenCliOptions& GlobalOptions, int argc, char** argv)
 {
 	ZEN_UNUSED(GlobalOptions);
 
 	if (!ParseOptions(argc, argv))
 	{
-		return 0;
+		return;
 	}
 
 	m_HostName = ResolveTargetHostSpec(m_HostName);
 
 	if (m_HostName.empty())
 	{
-		throw OptionParseException("unable to resolve server specification");
+		throw OptionParseException("Unable to resolve server specification", m_Options.help());
 	}
 
 	HttpClient Http(m_HostName);
@@ -2266,13 +2213,13 @@ OplogValidateCommand::Run(const ZenCliOptions& GlobalOptions, int argc, char** a
 	m_ProjectName = ResolveProject(Http, m_ProjectName);
 	if (m_ProjectName.empty())
 	{
-		return 1;
+		throw std::runtime_error("Project can not be found");
 	}
 
 	m_OplogName = ResolveOplog(Http, m_ProjectName, m_OplogName);
 	if (m_OplogName.empty())
 	{
-		return 1;
+		throw std::runtime_error("Oplog can not be found");
 	}
 
 	std::string Url = fmt::format("/prj/{}/oplog/{}/validate", m_ProjectName, m_OplogName);
@@ -2280,15 +2227,11 @@ OplogValidateCommand::Run(const ZenCliOptions& GlobalOptions, int argc, char** a
 	if (HttpClient::Response Result = Http.Post(Url, HttpClient::Accept(ZenContentType::kJSON)))
 	{
 		ZEN_CONSOLE("{}", Result.ToText());
-		return 0;
 	}
 	else
 	{
 		Result.ThrowError("failed to get validate project oplog"sv);
-		return 1;
 	}
-
-	return 0;
 }
 
 }  // namespace zen