Adds cmd option to just check config

[TheRandomCharacter]

Instead of starting dataplane returns result of dataplane config read and check.

[ol-imorozko]

Suggested change

	eResult cDataPlane::DryRun(const std::string& configFilePath)
	{
	eResult cDataPlane::DryRun(std::string_view configFilePath)
	{

We can use lightweight wrapper around const char* instead of creating dynamic std::string

[ol-imorozko]

same here

[ol-imorozko]

that means this function should also accept std::string_view, which in turn implies that init function should accept std::string_view.

In parseConfig we should do this, instead of creating std::ifstream from std::string:

eResult cDataPlane::parseConfig(std::string_view configFilePath)
{
    eResult result = eResult::success;
    std::filesystem::path path(configFilePath);
    std::ifstream fromFileStream(path);

In summary, the following diff is all we need:

diff --git a/dataplane/dataplane.cpp b/dataplane/dataplane.cpp
index 97d9c20..fcf4577 100644
--- a/dataplane/dataplane.cpp
+++ b/dataplane/dataplane.cpp
@@ -74,7 +74,7 @@ cDataPlane::~cDataPlane()
 }
 
 eResult cDataPlane::init(const std::string& binaryPath,
-                         const std::string& configFilePath)
+                         std::string_view configFilePath)
 {
 	eResult result = eResult::success;
 
@@ -265,7 +265,7 @@ eResult cDataPlane::init(const std::string& binaryPath,
 	return result;
 }
 
-eResult cDataPlane::DryRun(const std::string& configFilePath)
+eResult cDataPlane::DryRun(std::string_view configFilePath)
 {
 	return parseConfig(configFilePath);
 }
@@ -1867,11 +1867,12 @@ void cDataPlane::switch_worker_base()
 	controlPlane->switchBase();
 }
 
-eResult cDataPlane::parseConfig(const std::string& configFilePath)
+eResult cDataPlane::parseConfig(std::string_view configFilePath)
 {
 	eResult result = eResult::success;
+	std::filesystem::path path(configFilePath);
+	std::ifstream fromFileStream(path);
 
-	std::ifstream fromFileStream(configFilePath);
 	if (!fromFileStream.is_open())
 	{
 		YADECAP_LOG_ERROR("can't open file '%s'\n", configFilePath.data());
diff --git a/dataplane/dataplane.h b/dataplane/dataplane.h
index f1437ee..fc737f6 100644
--- a/dataplane/dataplane.h
+++ b/dataplane/dataplane.h
@@ -99,8 +99,8 @@ public:
 	~cDataPlane();
 
 	eResult init(const std::string& binaryPath,
-	             const std::string& configFilePath);
-	eResult DryRun(const std::string& configFilePath);
+	             std::string_view configFilePath);
+	eResult DryRun(std::string_view configFilePath);
 
 	void start();
 	void join();
@@ -122,7 +122,7 @@ public:
 	std::string InterfaceNameFromPort(tPortId id) { return std::get<0>(ports[id]); };
 
 protected:
-	eResult parseConfig(const std::string& configFilePath);
+	eResult parseConfig(std::string_view configFilePath);
 	eResult parseJsonPorts(const nlohmann::json& json);
 	std::optional<std::map<tCoreId, CPlaneWorkerConfig>> parseControlPlaneWorkers(const nlohmann::json& config);
 	std::optional<std::pair<tCoreId, CPlaneWorkerConfig>> parseControlPlaneWorker(const nlohmann::json& cpwj);

[GeorgyKirichenko]

I think it would be better to use json-schema instead, possibly somewhere outside dataplane or controlplane