src/sysrepo_access.cpp - CzechLight/netconf-cli - Gitiles

 /*
  * Copyright (C) 2018 CESNET, https://photonics.cesnet.cz/
  * Copyright (C) 2018 FIT CVUT, https://fit.cvut.cz/
  *
  * Written by Václav Kubernát <kubervac@fit.cvut.cz>
  *
 */

 #include <experimental/iterator>
 #include <libyang/Tree_Data.hpp>
 #include <libyang/Tree_Schema.hpp>
 #include <sstream>
 #include <sysrepo-cpp/Session.hpp>
 #include "libyang_utils.hpp"
 #include "sysrepo_access.hpp"
 #include "utils.hpp"
 #include "yang_schema.hpp"

 const auto OPERATION_TIMEOUT_MS = 1000;

 struct valFromValue : boost::static_visitor<sysrepo::S_Val> {
     sysrepo::S_Val operator()(const enum_& value) const
     {
         return std::make_shared<sysrepo::Val>(value.m_value.c_str(), SR_ENUM_T);
     }

     sysrepo::S_Val operator()(const binary_& value) const
     {
         return std::make_shared<sysrepo::Val>(value.m_value.c_str(), SR_BINARY_T);
     }

     sysrepo::S_Val operator()(const empty_) const
     {
         return std::make_shared<sysrepo::Val>(nullptr, SR_LEAF_EMPTY_T);
     }

     sysrepo::S_Val operator()(const identityRef_& value) const
     {
         auto res = value.m_prefix ? (value.m_prefix.value().m_name + ":" + value.m_value) : value.m_value;
         return std::make_shared<sysrepo::Val>(res.c_str(), SR_IDENTITYREF_T);
     }

     sysrepo::S_Val operator()(const special_& value) const
     {
         throw std::runtime_error("Tried constructing S_Val from a " + specialValueToString(value));
     }

     sysrepo::S_Val operator()(const std::string& value) const
     {
         return std::make_shared<sysrepo::Val>(value.c_str());
     }

     sysrepo::S_Val operator()(const bits_& value) const
     {
         std::stringstream ss;
         std::copy(value.m_bits.begin(), value.m_bits.end(), std::experimental::make_ostream_joiner(ss, " "));
         return std::make_shared<sysrepo::Val>(ss.str().c_str(), SR_BITS_T);
     }

     template <typename T>
     sysrepo::S_Val operator()(const T& value) const
     {
         return std::make_shared<sysrepo::Val>(value);
     }
 };

 SysrepoAccess::~SysrepoAccess() = default;

 sr_datastore_t toSrDatastore(Datastore datastore)
 {
     switch (datastore) {
     case Datastore::Running:
         return SR_DS_RUNNING;
     case Datastore::Startup:
         return SR_DS_STARTUP;
     }
     __builtin_unreachable();
 }

 SysrepoAccess::SysrepoAccess(const Datastore datastore)
     : m_connection(std::make_shared<sysrepo::Connection>())
     , m_session(std::make_shared<sysrepo::Session>(m_connection))
     , m_schema(std::make_shared<YangSchema>(m_session->get_context()))
 {
     try {
         m_session = std::make_shared<sysrepo::Session>(m_connection, toSrDatastore(datastore));
     } catch (sysrepo::sysrepo_exception& ex) {
         reportErrors();
     }
 }

 DatastoreAccess::Tree SysrepoAccess::getItems(const std::string& path) const
 {
     using namespace std::string_literals;
     Tree res;

     try {
         auto oldDs = m_session->session_get_ds();
         m_session->session_switch_ds(SR_DS_OPERATIONAL);
         auto config = m_session->get_data(((path == "/") ? "/*" : path).c_str());
         m_session->session_switch_ds(oldDs);
         if (config) {
             lyNodesToTree(res, config->tree_for());
         }
     } catch (sysrepo::sysrepo_exception& ex) {
         reportErrors();
     }
     return res;
 }

 void SysrepoAccess::setLeaf(const std::string& path, leaf_data_ value)
 {
     try {
         m_session->set_item(path.c_str(), boost::apply_visitor(valFromValue(), value));
     } catch (sysrepo::sysrepo_exception& ex) {
         reportErrors();
     }
 }

 void SysrepoAccess::createItem(const std::string& path)
 {
     try {
         m_session->set_item(path.c_str());
     } catch (sysrepo::sysrepo_exception& ex) {
         reportErrors();
     }
 }

 void SysrepoAccess::deleteItem(const std::string& path)
 {
     try {
         // Have to use SR_EDIT_ISOLATE, because deleting something that's been set without committing is not supported
         // https://github.com/sysrepo/sysrepo/issues/1967#issuecomment-625085090
         m_session->delete_item(path.c_str(), SR_EDIT_ISOLATE);
     } catch (sysrepo::sysrepo_exception& ex) {
         reportErrors();
     }
 }

 struct impl_toSrMoveOp {
     sr_move_position_t operator()(yang::move::Absolute& absolute)
     {
         return absolute == yang::move::Absolute::Begin ? SR_MOVE_FIRST : SR_MOVE_LAST;
     }
     sr_move_position_t operator()(yang::move::Relative& relative)
     {
         return relative.m_position == yang::move::Relative::Position::After ? SR_MOVE_AFTER : SR_MOVE_BEFORE;
     }
 };

 sr_move_position_t toSrMoveOp(std::variant<yang::move::Absolute, yang::move::Relative> move)
 {
     return std::visit(impl_toSrMoveOp{}, move);
 }

 void SysrepoAccess::moveItem(const std::string& source, std::variant<yang::move::Absolute, yang::move::Relative> move)
 {
     std::string destination;
     if (std::holds_alternative<yang::move::Relative>(move)) {
         auto relative = std::get<yang::move::Relative>(move);
         if (m_schema->nodeType(source) == yang::NodeTypes::LeafList) {
             destination = leafDataToString(relative.m_path.at("."));
         } else {
             destination = instanceToString(relative.m_path);
         }
     }
     m_session->move_item(source.c_str(), toSrMoveOp(move), destination.c_str(), destination.c_str());
 }

 void SysrepoAccess::commitChanges()
 {
     try {
         m_session->apply_changes(OPERATION_TIMEOUT_MS, 1);
     } catch (sysrepo::sysrepo_exception& ex) {
         reportErrors();
     }
 }

 void SysrepoAccess::discardChanges()
 {
     try {
         m_session->discard_changes();
     } catch (sysrepo::sysrepo_exception& ex) {
         reportErrors();
     }
 }

 DatastoreAccess::Tree SysrepoAccess::execute(const std::string& path, const Tree& input)
 {
     auto inputNode = treeToRpcInput(m_session->get_context(), path, input);
     auto output = m_session->rpc_send(inputNode);
     return rpcOutputToTree(path, output);
 }

 void SysrepoAccess::copyConfig(const Datastore source, const Datastore destination)
 {
     auto oldDs = m_session->session_get_ds();
     m_session->session_switch_ds(toSrDatastore(destination));
     m_session->copy_config(toSrDatastore(source), nullptr, OPERATION_TIMEOUT_MS, 1);
     m_session->session_switch_ds(oldDs);
 }

 std::shared_ptr<Schema> SysrepoAccess::schema()
 {
     return m_schema;
 }

 [[noreturn]] void SysrepoAccess::reportErrors() const
 {
     // I only use get_error to get error info, since the error code from
     // sysrepo_exception doesn't really give any meaningful information. For
     // example an "invalid argument" error could mean a node isn't enabled, or
     // it could mean something totally different and there is no documentation
     // for that, so it's better to just use the message sysrepo gives me.
     auto srErrors = m_session->get_error();
     std::vector<DatastoreError> res;

     for (size_t i = 0; i < srErrors->error_cnt(); i++) {
         res.emplace_back(srErrors->message(i), srErrors->xpath(i) ? std::optional<std::string>{srErrors->xpath(i)} : std::nullopt);
     }

     throw DatastoreException(res);
 }

 std::vector<ListInstance> SysrepoAccess::listInstances(const std::string& path)
 {
     std::vector<ListInstance> res;
     auto lists = getItems(path);

     decltype(lists) instances;
     auto wantedTree = *(m_schema->dataNodeFromPath(path)->find_path(path.c_str())->data().begin());
     std::copy_if(lists.begin(), lists.end(), std::inserter(instances, instances.end()), [this, pathToCheck = wantedTree->schema()->path()](const auto& item) {
         // This filters out non-instances.
         if (item.second.type() != typeid(special_) || boost::get<special_>(item.second).m_value != SpecialValue::List) {
             return false;
         }

         // Now, getItems is recursive: it gives everything including nested lists. So I try create a tree from the instance...
         auto instanceTree = *(m_schema->dataNodeFromPath(item.first)->find_path(item.first.c_str())->data().begin());
         // And then check if its schema path matches the list we actually want. This filters out lists which are not the ones I requested.
         return instanceTree->schema()->path() == pathToCheck;
     });

     // If there are no instances, then just return
     if (instances.empty()) {
         return res;
     }

     // I need to find out which keys does the list have. To do that, I create a
     // tree from the first instance. This is gives me some top level node,
     // which will be our list in case out list is a top-level node. In case it
     // isn't, we have call find_path on the top level node. After that, I just
     // retrieve the keys.
     auto topLevelTree = m_schema->dataNodeFromPath(instances.begin()->first);
     auto list = *(topLevelTree->find_path(path.c_str())->data().begin());
     auto keys = libyang::Schema_Node_List{list->schema()}.keys();

     // Creating a full tree at the same time from the values sysrepo gives me
     // would be a pain (and after sysrepo switches to libyang meaningless), so
     // I just use this algorithm to create data nodes one by one and get the
     // key values from them.
     for (const auto& instance : instances) {
         auto wantedList = *(m_schema->dataNodeFromPath(instance.first)->find_path(path.c_str())->data().begin());
         ListInstance instanceRes;
         for (const auto& key : keys) {
             auto vec = wantedList->find_path(key->name())->data();
             auto leaf = std::make_shared<libyang::Data_Node_Leaf_List>(*(vec.begin()));
             instanceRes.emplace(key->name(), leafValueFromNode(leaf));
         }
         res.emplace_back(instanceRes);
     }

     return res;
 }

 std::string SysrepoAccess::dump(const DataFormat format) const
 {
     auto root = m_session->get_data("/*");
     return root->print_mem(format == DataFormat::Xml ? LYD_XML : LYD_JSON, LYP_WITHSIBLINGS | LYP_FORMAT);
 }
	/*
	* Copyright (C) 2018 CESNET, https://photonics.cesnet.cz/
	* Copyright (C) 2018 FIT CVUT, https://fit.cvut.cz/
	*
	* Written by Václav Kubernát <kubervac@fit.cvut.cz>
	*
	*/

	#include <experimental/iterator>
	#include <libyang/Tree_Data.hpp>
	#include <libyang/Tree_Schema.hpp>
	#include <sstream>
	#include <sysrepo-cpp/Session.hpp>
	#include "libyang_utils.hpp"
	#include "sysrepo_access.hpp"
	#include "utils.hpp"
	#include "yang_schema.hpp"

	const auto OPERATION_TIMEOUT_MS = 1000;

	struct valFromValue : boost::static_visitor<sysrepo::S_Val> {
	sysrepo::S_Val operator()(const enum_& value) const
	{
	return std::make_shared<sysrepo::Val>(value.m_value.c_str(), SR_ENUM_T);
	}

	sysrepo::S_Val operator()(const binary_& value) const
	{
	return std::make_shared<sysrepo::Val>(value.m_value.c_str(), SR_BINARY_T);
	}

	sysrepo::S_Val operator()(const empty_) const
	{
	return std::make_shared<sysrepo::Val>(nullptr, SR_LEAF_EMPTY_T);
	}

	sysrepo::S_Val operator()(const identityRef_& value) const
	{
	auto res = value.m_prefix ? (value.m_prefix.value().m_name + ":" + value.m_value) : value.m_value;
	return std::make_shared<sysrepo::Val>(res.c_str(), SR_IDENTITYREF_T);
	}

	sysrepo::S_Val operator()(const special_& value) const
	{
	throw std::runtime_error("Tried constructing S_Val from a " + specialValueToString(value));
	}

	sysrepo::S_Val operator()(const std::string& value) const
	{
	return std::make_shared<sysrepo::Val>(value.c_str());
	}

	sysrepo::S_Val operator()(const bits_& value) const
	{
	std::stringstream ss;
	std::copy(value.m_bits.begin(), value.m_bits.end(), std::experimental::make_ostream_joiner(ss, " "));
	return std::make_shared<sysrepo::Val>(ss.str().c_str(), SR_BITS_T);
	}

	template <typename T>
	sysrepo::S_Val operator()(const T& value) const
	{
	return std::make_shared<sysrepo::Val>(value);
	}
	};

	SysrepoAccess::~SysrepoAccess() = default;

	sr_datastore_t toSrDatastore(Datastore datastore)
	{
	switch (datastore) {
	case Datastore::Running:
	return SR_DS_RUNNING;
	case Datastore::Startup:
	return SR_DS_STARTUP;
	}
	__builtin_unreachable();
	}

	SysrepoAccess::SysrepoAccess(const Datastore datastore)
	: m_connection(std::make_shared<sysrepo::Connection>())
	, m_session(std::make_shared<sysrepo::Session>(m_connection))
	, m_schema(std::make_shared<YangSchema>(m_session->get_context()))
	{
	try {
	m_session = std::make_shared<sysrepo::Session>(m_connection, toSrDatastore(datastore));
	} catch (sysrepo::sysrepo_exception& ex) {
	reportErrors();
	}
	}

	DatastoreAccess::Tree SysrepoAccess::getItems(const std::string& path) const
	{
	using namespace std::string_literals;
	Tree res;

	try {
	auto oldDs = m_session->session_get_ds();
	m_session->session_switch_ds(SR_DS_OPERATIONAL);
	auto config = m_session->get_data(((path == "/") ? "/*" : path).c_str());
	m_session->session_switch_ds(oldDs);
	if (config) {
	lyNodesToTree(res, config->tree_for());
	}
	} catch (sysrepo::sysrepo_exception& ex) {
	reportErrors();
	}
	return res;
	}

	void SysrepoAccess::setLeaf(const std::string& path, leaf_data_ value)
	{
	try {
	m_session->set_item(path.c_str(), boost::apply_visitor(valFromValue(), value));
	} catch (sysrepo::sysrepo_exception& ex) {
	reportErrors();
	}
	}

	void SysrepoAccess::createItem(const std::string& path)
	{
	try {
	m_session->set_item(path.c_str());
	} catch (sysrepo::sysrepo_exception& ex) {
	reportErrors();
	}
	}

	void SysrepoAccess::deleteItem(const std::string& path)
	{
	try {
	// Have to use SR_EDIT_ISOLATE, because deleting something that's been set without committing is not supported
	// https://github.com/sysrepo/sysrepo/issues/1967#issuecomment-625085090
	m_session->delete_item(path.c_str(), SR_EDIT_ISOLATE);
	} catch (sysrepo::sysrepo_exception& ex) {
	reportErrors();
	}
	}

	struct impl_toSrMoveOp {
	sr_move_position_t operator()(yang::move::Absolute& absolute)
	{
	return absolute == yang::move::Absolute::Begin ? SR_MOVE_FIRST : SR_MOVE_LAST;
	}
	sr_move_position_t operator()(yang::move::Relative& relative)
	{
	return relative.m_position == yang::move::Relative::Position::After ? SR_MOVE_AFTER : SR_MOVE_BEFORE;
	}
	};

	sr_move_position_t toSrMoveOp(std::variant<yang::move::Absolute, yang::move::Relative> move)
	{
	return std::visit(impl_toSrMoveOp{}, move);
	}

	void SysrepoAccess::moveItem(const std::string& source, std::variant<yang::move::Absolute, yang::move::Relative> move)
	{
	std::string destination;
	if (std::holds_alternative<yang::move::Relative>(move)) {
	auto relative = std::get<yang::move::Relative>(move);
	if (m_schema->nodeType(source) == yang::NodeTypes::LeafList) {
	destination = leafDataToString(relative.m_path.at("."));
	} else {
	destination = instanceToString(relative.m_path);
	}
	}
	m_session->move_item(source.c_str(), toSrMoveOp(move), destination.c_str(), destination.c_str());
	}

	void SysrepoAccess::commitChanges()
	{
	try {
	m_session->apply_changes(OPERATION_TIMEOUT_MS, 1);
	} catch (sysrepo::sysrepo_exception& ex) {
	reportErrors();
	}
	}

	void SysrepoAccess::discardChanges()
	{
	try {
	m_session->discard_changes();
	} catch (sysrepo::sysrepo_exception& ex) {
	reportErrors();
	}
	}

	DatastoreAccess::Tree SysrepoAccess::execute(const std::string& path, const Tree& input)
	{
	auto inputNode = treeToRpcInput(m_session->get_context(), path, input);
	auto output = m_session->rpc_send(inputNode);
	return rpcOutputToTree(path, output);
	}

	void SysrepoAccess::copyConfig(const Datastore source, const Datastore destination)
	{
	auto oldDs = m_session->session_get_ds();
	m_session->session_switch_ds(toSrDatastore(destination));
	m_session->copy_config(toSrDatastore(source), nullptr, OPERATION_TIMEOUT_MS, 1);
	m_session->session_switch_ds(oldDs);
	}

	std::shared_ptr<Schema> SysrepoAccess::schema()
	{
	return m_schema;
	}

	[[noreturn]] void SysrepoAccess::reportErrors() const
	{
	// I only use get_error to get error info, since the error code from
	// sysrepo_exception doesn't really give any meaningful information. For
	// example an "invalid argument" error could mean a node isn't enabled, or
	// it could mean something totally different and there is no documentation
	// for that, so it's better to just use the message sysrepo gives me.
	auto srErrors = m_session->get_error();
	std::vector<DatastoreError> res;

	for (size_t i = 0; i < srErrors->error_cnt(); i++) {
	res.emplace_back(srErrors->message(i), srErrors->xpath(i) ? std::optional<std::string>{srErrors->xpath(i)} : std::nullopt);
	}

	throw DatastoreException(res);
	}

	std::vector<ListInstance> SysrepoAccess::listInstances(const std::string& path)
	{
	std::vector<ListInstance> res;
	auto lists = getItems(path);

	decltype(lists) instances;
	auto wantedTree = *(m_schema->dataNodeFromPath(path)->find_path(path.c_str())->data().begin());
	std::copy_if(lists.begin(), lists.end(), std::inserter(instances, instances.end()), [this, pathToCheck = wantedTree->schema()->path()](const auto& item) {
	// This filters out non-instances.
	if (item.second.type() != typeid(special_) \|\| boost::get<special_>(item.second).m_value != SpecialValue::List) {
	return false;
	}

	// Now, getItems is recursive: it gives everything including nested lists. So I try create a tree from the instance...
	auto instanceTree = *(m_schema->dataNodeFromPath(item.first)->find_path(item.first.c_str())->data().begin());
	// And then check if its schema path matches the list we actually want. This filters out lists which are not the ones I requested.
	return instanceTree->schema()->path() == pathToCheck;
	});

	// If there are no instances, then just return
	if (instances.empty()) {
	return res;
	}

	// I need to find out which keys does the list have. To do that, I create a
	// tree from the first instance. This is gives me some top level node,
	// which will be our list in case out list is a top-level node. In case it
	// isn't, we have call find_path on the top level node. After that, I just
	// retrieve the keys.
	auto topLevelTree = m_schema->dataNodeFromPath(instances.begin()->first);
	auto list = *(topLevelTree->find_path(path.c_str())->data().begin());
	auto keys = libyang::Schema_Node_List{list->schema()}.keys();

	// Creating a full tree at the same time from the values sysrepo gives me
	// would be a pain (and after sysrepo switches to libyang meaningless), so
	// I just use this algorithm to create data nodes one by one and get the
	// key values from them.
	for (const auto& instance : instances) {
	auto wantedList = *(m_schema->dataNodeFromPath(instance.first)->find_path(path.c_str())->data().begin());
	ListInstance instanceRes;
	for (const auto& key : keys) {
	auto vec = wantedList->find_path(key->name())->data();
	auto leaf = std::make_shared<libyang::Data_Node_Leaf_List>(*(vec.begin()));
	instanceRes.emplace(key->name(), leafValueFromNode(leaf));
	}
	res.emplace_back(instanceRes);
	}

	return res;
	}

	std::string SysrepoAccess::dump(const DataFormat format) const
	{
	auto root = m_session->get_data("/*");
	return root->print_mem(format == DataFormat::Xml ? LYD_XML : LYD_JSON, LYP_WITHSIBLINGS \| LYP_FORMAT);
	}