A simple parser. More...

#include <simple_parser.h>

Inheritance diagram for isc::data::SimpleParser:

Public Member Functions
uint16_t	getUint16 (isc::data::ConstElementPtr scope, const std::string &name)
	Returns a value converted to uint16_t.

uint32_t	getUint32 (isc::data::ConstElementPtr scope, const std::string &name)
	Returns a value converted to uint32_t.

uint8_t	getUint8 (ConstElementPtr scope, const std::string &name)
	Get an uint8_t value.

const isc::util::Triplet< uint32_t >	parseIntTriplet (const data::ConstElementPtr &scope, const std::string &name)
	Parses an integer triplet.

Static Public Member Functions
static void	checkKeywords (const SimpleKeywords &keywords, isc::data::ConstElementPtr scope)
	Checks acceptable keywords with their expected type.

static void	checkRequired (const SimpleRequiredKeywords &required, isc::data::ConstElementPtr scope)
	Checks that all required keywords are present.

static size_t	deriveParams (isc::data::ConstElementPtr parent, isc::data::ElementPtr child, const ParamsList &params)
	Derives (inherits) parameters from parent scope to a child.

static isc::asiolink::IOAddress	getAddress (const ConstElementPtr &scope, const std::string &name)
	Returns a IOAddress parameter from a scope.

static bool	getBoolean (isc::data::ConstElementPtr scope, const std::string &name)
	Returns a boolean parameter from a scope.

static double	getDouble (const ConstElementPtr &scope, const std::string &name)
	Returns a floating point parameter from a scope.

static int64_t	getInteger (isc::data::ConstElementPtr scope, const std::string &name)
	Returns an integer parameter from a scope.

static int64_t	getInteger (isc::data::ConstElementPtr scope, const std::string &name, int64_t min, int64_t max)
	Returns an integer parameter from a scope and checks its range.

static const data::Element::Position &	getPosition (const std::string &name, const data::ConstElementPtr parent)
	Utility method that returns position of an element.

static std::string	getString (isc::data::ConstElementPtr scope, const std::string &name)
	Returns a string parameter from a scope.

static size_t	setDefaults (isc::data::ElementPtr scope, const SimpleDefaults &default_values)
	Sets the default values.

static size_t	setListDefaults (isc::data::ConstElementPtr list, const SimpleDefaults &default_values)
	Sets the default values for all entries in a list.

Protected Member Functions
template<typename target_type , target_type convert>
target_type	getAndConvert (isc::data::ConstElementPtr scope, const std::string &name, const std::string &type_name)
	Returns a converted value from a scope.

template<typename int_type >
int_type	getIntType (isc::data::ConstElementPtr scope, const std::string &name)
	Returns an integer value with range checking from a scope.

Detailed Description

A simple parser.

This class is intended to be a simpler replacement for DhcpConfigParser. This class has been initially created to facilitate DHCPv4 and DHCPv6 servers' configuration parsing. Thus examples provided herein are related to DHCP configuration. Nevertheless, this is a generic class to be used in other modules too.

The simplification comes from several factors:

no build/commit nonsense. There's a single step: CfgStorage parse(ConstElementPtr json) that converts JSON configuration into an object and returns it.
no state kept. This greatly simplifies the parsers (no contexts, no child parsers list, no separate storage for uint32, strings etc. In fact, this base class is purely static. However, some derived classes may store some state. Implementors are advised to store as little state as possible.
no optional parameters (all are mandatory). This simplifies the parser, but introduces a new step before parsing where we insert the default values into client configuration before parsing. This is actually a good thing, because we now have a clear picture of the default parameters as they're defined in a single place (the DhcpConfigParser had the defaults spread out in multiple files in multiple directories).

Definition at line 68 of file lib/cc/simple_parser.h.

Member Function Documentation

◆ checkKeywords()

void isc::data::SimpleParser::checkKeywords	(	const SimpleKeywords &	keywords,
		isc::data::ConstElementPtr	scope
	)

static

Checks acceptable keywords with their expected type.

This methods throws an exception when a not acceptable keyword is found or when an acceptable entry does not have the expected type.

Parameters

keywords	The `SimpleKeywords` keywords and types map.
scope	Specified parameters which are checked.

Exceptions

DhcpConfigError	if a not acceptable keyword is found.
DhcpConfigError	if an acceptable entry does not have the expected type.

Definition at line 35 of file lib/cc/simple_parser.cc.

References isc::data::Element::any, isc::data::Element::integer, isc_throw, and isc::data::Element::typeToName().

Referenced by isc::dhcp::SharedNetwork4Parser::parse(), isc::dhcp::SharedNetwork6Parser::parse(), isc::perfmon::PerfMonConfig::parse(), isc::perfmon::DurationKeyParser::parse(), isc::perfmon::AlarmParser::parse(), isc::dhcp::Subnet4ConfigParser::parse(), isc::dhcp::Subnet6ConfigParser::parse(), isc::dhcp::OptionDefParser::parse(), isc::dhcp::OptionDataParser::parse(), isc::dhcp::PdPoolParser::parse(), and isc::dhcp::PoolParser::parse().

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◆ checkRequired()

void isc::data::SimpleParser::checkRequired	(	const SimpleRequiredKeywords &	required,
		isc::data::ConstElementPtr	scope
	)

static

Checks that all required keywords are present.

This method throws an exception when a required entry is not present in the given scope.

Parameters

required	Required keywords.
scope	Specified parameters which are checked.

Exceptions

DhcpConfigError if a required parameter is not present.

Definition at line 24 of file lib/cc/simple_parser.cc.

References isc_throw.

◆ deriveParams()

size_t isc::data::SimpleParser::deriveParams	(	isc::data::ConstElementPtr	parent,
		isc::data::ElementPtr	child,
		const ParamsList &	params
	)

static

Derives (inherits) parameters from parent scope to a child.

This method derives parameters from the parent scope to the child, if there are no values specified in the child scope. For example, this method can be used to derive timers from global scope (e.g. for the whole DHCPv6 server) to a subnet scope. This method checks if the child scope doesn't have more specific values defined. If it doesn't, then the value from parent scope is copied over.

Parameters

parent	scope to copy from (e.g. global)
child	scope to copy from (e.g. subnet)
params	names of the parameters to copy

Returns: number of parameters copied

Definition at line 254 of file lib/cc/simple_parser.cc.

References isc::data::Element::map.

Referenced by isc::netconf::NetconfSimpleParser::deriveParameters(), isc::dhcp::SimpleParser4::deriveParameters(), and isc::dhcp::SimpleParser6::deriveParameters().

◆ getAddress()

IOAddress isc::data::SimpleParser::getAddress	(	const ConstElementPtr &	scope,
		const std::string &	name
	)

static

Returns a IOAddress parameter from a scope.

Unconditionally returns a parameter.

Parameters

scope	specified parameter will be extracted from this scope
name	name of the parameter

Returns: an IOAddress representing the value of the parameter

Exceptions

DhcpConfigError if the parameter is not there or is not of appropriate type (or its conversion to IOAddress fails due to not being a proper address).

Definition at line 125 of file lib/cc/simple_parser.cc.

References getPosition(), getString(), isc_throw, and isc::Exception::what().

Referenced by isc::d2::D2SimpleParser::parse(), isc::dhcp::D2ClientConfigParser::parse(), isc::lease_cmds::Lease4Parser::parse(), and isc::lease_cmds::Lease6Parser::parse().

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◆ getAndConvert()

template<typename target_type , target_type convert>

target_type isc::data::SimpleParser::getAndConvert	(	isc::data::ConstElementPtr	scope,
		const std::string &	name,
		const std::string &	type_name
	)

inlineprotected

Returns a converted value from a scope.

This template should be instantiated in parsers when useful

Template Parameters

target_type	the type of the result
convert	the conversion function std::string -> target_type

Parameters

scope	specified parameter will be extracted from this scope
name	name of the parameter for error report
type_name	name of target_type for error report

Returns: a converted value of target_type

Exceptions

DhcpConfigError if the parameter is not there, is not of appropriate type or can not be converted

Definition at line 269 of file lib/cc/simple_parser.h.

References getPosition(), getString(), and isc_throw.

Referenced by isc::dhcp::BaseNetworkParser::parseDdnsParams().

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◆ getBoolean()

bool isc::data::SimpleParser::getBoolean	(	isc::data::ConstElementPtr	scope,
		const std::string &	name
	)

static

Returns a boolean parameter from a scope.

Unconditionally returns a parameter.

Parameters

scope	specified parameter will be extracted from this scope
name	name of the parameter

Returns: a boolean value of the parameter

Exceptions

DhcpConfigError if the parameter is not there or is not of appropriate type

Definition at line 108 of file lib/cc/simple_parser.cc.

References isc::data::Element::boolean, and isc_throw.

◆ getDouble()

double isc::data::SimpleParser::getDouble	(	const ConstElementPtr &	scope,
		const std::string &	name
	)

static

Returns a floating point parameter from a scope.

Unconditionally returns a parameter.

Parameters

scope	specified parameter will be extracted from this scope
name	name of the parameter

Returns: a double value of the parameter

Exceptions

DhcpConfigError if the parameter is not there or is not an Element::real

Definition at line 138 of file lib/cc/simple_parser.cc.

References isc_throw, and isc::data::Element::real.

Referenced by isc::dhcp::BaseNetworkParser::parseCacheParams(), isc::dhcp::BaseNetworkParser::parseDdnsParams(), and isc::dhcp::BaseNetworkParser::parseTeePercents().

◆ getInteger() [1/2]

int64_t isc::data::SimpleParser::getInteger	(	isc::data::ConstElementPtr	scope,
		const std::string &	name
	)

static

Returns an integer parameter from a scope.

Unconditionally returns a parameter.

Parameters

scope	specified parameter will be extracted from this scope
name	name of the parameter

Returns: an integer value of the parameter

Exceptions

DhcpConfigError if the parameter is not there or is not of appropriate type

Definition at line 77 of file lib/cc/simple_parser.cc.

References isc::data::Element::integer, and isc_throw.

◆ getInteger() [2/2]

int64_t isc::data::SimpleParser::getInteger	(	isc::data::ConstElementPtr	scope,
		const std::string &	name,
		int64_t	min,
		int64_t	max
	)

static

Returns an integer parameter from a scope and checks its range.

Unconditionally returns a parameter. Checks that the value specified is in min =< X =< max range.

Parameters

scope	specified parameter will be extracted from this scope
name	name of the parameter
min	minimum allowed value
max	maximum allowed value

Returns: an integer value of the parameter

Exceptions

DhcpConfigError	if the parameter is not there or is not of appropriate type.
OutOfRange	if the parameter is out of range

Definition at line 94 of file lib/cc/simple_parser.cc.

References getInteger(), and isc_throw.

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◆ getIntType()

template<typename int_type >

int_type isc::data::SimpleParser::getIntType	(	isc::data::ConstElementPtr	scope,
		const std::string &	name
	)

inlineprotected

Returns an integer value with range checking from a scope.

This template should be instantiated in parsers when useful

Template Parameters

int_type the integer type e.g. uint32_t

Parameters

scope	specified parameter will be extracted from this scope
name	name of the parameter for error report

Returns: a value of int_type

Exceptions

DhcpConfigError if the parameter is not there, is not of appropriate type or is out of type value range

Definition at line 242 of file lib/cc/simple_parser.h.

References getInteger(), getPosition(), and isc_throw.

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◆ getPosition()

const data::Element::Position & isc::data::SimpleParser::getPosition	(	const std::string &	name,
		const data::ConstElementPtr	parent
	)

static

Utility method that returns position of an element.

It's mostly useful for logging. If the element is missing the parent position is returned or ZERO_POSITION if parent is null.

Parameters

name	position of that element will be returned
parent	parent element (optional)

Returns: position of the element specified.

Definition at line 158 of file lib/cc/simple_parser.cc.

References isc::data::Element::ZERO_POSITION().

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◆ getString()

std::string isc::data::SimpleParser::getString	(	isc::data::ConstElementPtr	scope,
		const std::string &	name
	)

static

Returns a string parameter from a scope.

Unconditionally returns a parameter.

Parameters

scope	specified parameter will be extracted from this scope
name	name of the parameter

Returns: a string value of the parameter

Exceptions

DhcpConfigError if the parameter is not there or is not of appropriate type

Definition at line 60 of file lib/cc/simple_parser.cc.

References isc_throw, and isc::data::Element::string.

◆ getUint16()

uint16_t isc::data::SimpleParser::getUint16	(	isc::data::ConstElementPtr	scope,
		const std::string &	name
	)

inline

Returns a value converted to uint16_t.

Instantiation of getIntType() to uint16_t

Parameters

scope	specified parameter will be extracted from this scope
name	name of the parameter

Returns: an uint16_t value

Exceptions

isc::dhcp::DhcpConfigError when it is not an uint16_t

Definition at line 305 of file lib/cc/simple_parser.h.

Referenced by isc::dhcp::DUIDConfigParser::parse().

◆ getUint32()

uint32_t isc::data::SimpleParser::getUint32	(	isc::data::ConstElementPtr	scope,
		const std::string &	name
	)

inline

Returns a value converted to uint32_t.

Instantiation of getIntType() to uint32_t

Parameters

scope	specified parameter will be extracted from this scope
name	name of the parameter

Returns: an uint32_t value

Exceptions

isc::dhcp::DhcpConfigError when it is not an uint32_t

Definition at line 292 of file lib/cc/simple_parser.h.

Referenced by isc::lease_cmds::LeaseCmdsImpl::lease4WipeHandler(), isc::lease_cmds::LeaseCmdsImpl::lease6WipeHandler(), isc::dhcp::DUIDConfigParser::parse(), isc::d2::D2SimpleParser::parse(), isc::dhcp::D2ClientConfigParser::parse(), isc::lease_cmds::Lease4Parser::parse(), and isc::lease_cmds::Lease6Parser::parse().

◆ getUint8()

uint8_t isc::data::SimpleParser::getUint8	(	ConstElementPtr	scope,
		const std::string &	name
	)

inline

Get an uint8_t value.

Instantiation of getIntType() to uint8_t

Parameters

scope	specified parameter will be extracted from this scope
name	name of the parameter

Returns: uint8_t value

Exceptions

isc::dhcp::DhcpConfigError when it is not an uint8_t

Definition at line 318 of file lib/cc/simple_parser.h.

Referenced by isc::lease_cmds::Lease4Parser::parse(), isc::lease_cmds::Lease6Parser::parse(), and isc::dhcp::PdPoolParser::parse().

◆ parseIntTriplet()

const util::Triplet< uint32_t > isc::data::SimpleParser::parseIntTriplet	(	const data::ConstElementPtr &	scope,
		const std::string &	name
	)

Parses an integer triplet.

Parses an integer triplet parameter of the form:

min-{name}, {name}, max-{name}

Parameters

scope	Data element holding e.g. shared network configuration to be parsed.
name	Base name of the parameter.

Returns: A triplet with the parsed value.

Definition at line 286 of file lib/cc/simple_parser.cc.

References getInteger(), and isc_throw.

Referenced by isc::dhcp::Subnet6ConfigParser::initSubnet(), isc::dhcp::ClientClassDefParser::parse(), isc::dhcp::SharedNetwork6Parser::parse(), and isc::dhcp::BaseNetworkParser::parseCommon().

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◆ setDefaults()

size_t isc::data::SimpleParser::setDefaults	(	isc::data::ElementPtr	scope,
		const SimpleDefaults &	default_values
	)

static

Sets the default values.

This method sets the default values for parameters that are not defined. The list of default values is specified by default_values. If not present, those will be inserted into the scope. If a parameter is already present, the default value will not be inserted.

Parameters

scope	default values will be inserted here
default_values	list of default values

Returns: number of parameters inserted

Definition at line 170 of file lib/cc/simple_parser.cc.

References isc::data::Element::boolean, isc::data::Element::integer, isc_throw, isc::data::Element::real, and isc::data::Element::string.

Referenced by isc::agent::AgentSimpleParser::setAllDefaults(), isc::netconf::NetconfSimpleParser::setAllDefaults(), isc::d2::D2SimpleParser::setAllDefaults(), isc::dhcp::D2ClientConfigParser::setAllDefaults(), isc::dhcp::SimpleParser4::setAllDefaults(), isc::dhcp::SimpleParser6::setAllDefaults(), isc::d2::D2SimpleParser::setDdnsDomainDefaults(), setListDefaults(), isc::d2::D2SimpleParser::setManagerDefaults(), and isc::netconf::NetconfSimpleParser::setServerDefaults().

◆ setListDefaults()

size_t isc::data::SimpleParser::setListDefaults	(	isc::data::ConstElementPtr	list,
		const SimpleDefaults &	default_values
	)

static

Sets the default values for all entries in a list.

This is a simple utility method that iterates over all parameters in a list and calls setDefaults for each entry.

Parameters

list	list to be iterated over
default_values	list of default values

Returns: number of parameters inserted

Definition at line 244 of file lib/cc/simple_parser.cc.

References setDefaults().

Referenced by isc::dhcp::ClientClassDefParser::parse(), isc::d2::D2SimpleParser::setAllDefaults(), isc::dhcp::SimpleParser4::setAllDefaults(), isc::dhcp::SimpleParser6::setAllDefaults(), and isc::d2::D2SimpleParser::setDdnsDomainDefaults().

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The documentation for this class was generated from the following files:

Public Member Functions

Static Public Member Functions

Protected Member Functions

Detailed Description

Member Function Documentation

◆ checkKeywords()

◆ checkRequired()

◆ deriveParams()

◆ getAddress()

◆ getAndConvert()

◆ getBoolean()

◆ getDouble()

◆ getInteger() [1/2]

◆ getInteger() [2/2]

◆ getIntType()

◆ getPosition()

◆ getString()

◆ getUint16()

◆ getUint32()

◆ getUint8()

◆ parseIntTriplet()

◆ setDefaults()

◆ setListDefaults()