Compiler

Compile a JSON Schema into a set of low-level instructions for fast evaluation. More...

Classes
struct	sourcemeta::blaze::SchemaContext
struct	sourcemeta::blaze::DynamicContext
struct	sourcemeta::blaze::Tweaks
struct	sourcemeta::blaze::Context
struct	sourcemeta::blaze::SchemaUnevaluatedEntry

Typedefs
using	sourcemeta::blaze::Compiler = std::function< Instructions(const Context &, const SchemaContext &, const DynamicContext &, const Instructions &)>
using	sourcemeta::blaze::SchemaUnevaluatedEntries = std::map< sourcemeta::core::JSON::String, SchemaUnevaluatedEntry >

Functions
auto	sourcemeta::blaze::default_schema_compiler (const Context &, const SchemaContext &, const DynamicContext &, const Instructions &) -> Instructions
auto	sourcemeta::blaze::compile (const sourcemeta::core::JSON &schema, const sourcemeta::blaze::SchemaWalker &walker, const sourcemeta::blaze::SchemaResolver &resolver, const Compiler &compiler, const Mode mode=Mode::FastValidation, const std::string_view default_dialect="", const std::string_view default_id="", const std::string_view entrypoint="", const std::optional< Tweaks > &tweaks=std::nullopt) -> Template
auto	sourcemeta::blaze::compile (const sourcemeta::core::JSON &schema, const sourcemeta::blaze::SchemaWalker &walker, const sourcemeta::blaze::SchemaResolver &resolver, const Compiler &compiler, const sourcemeta::blaze::SchemaFrame &frame, const std::string_view entrypoint, const Mode mode=Mode::FastValidation, const std::optional< Tweaks > &tweaks=std::nullopt) -> Template
auto	sourcemeta::blaze::compile (const Context &context, const SchemaContext &schema_context, const DynamicContext &dynamic_context, const sourcemeta::core::WeakPointer &schema_suffix, const sourcemeta::core::WeakPointer &instance_suffix=sourcemeta::core::empty_weak_pointer, std::optional< std::string_view > uri=std::nullopt) -> Instructions
auto	sourcemeta::blaze::to_json (const Template &schema_template) -> sourcemeta::core::JSON

Detailed Description

Compile a JSON Schema into a set of low-level instructions for fast evaluation.

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Class Documentation

sourcemeta::blaze::SchemaContext

struct sourcemeta::blaze::SchemaContext

The schema compiler context is the current subschema information you have at your disposal to implement a keyword

Public Attributes
const sourcemeta::core::WeakPointer &	relative_pointer
	The schema location relative to the base URI.
const sourcemeta::core::JSON &	schema
	The current subschema.
const sourcemeta::blaze::Vocabularies &	vocabularies
	The schema vocabularies in use.
const sourcemeta::core::URI &	base
	The schema base URI.
bool	is_property_name
	Whether the current schema targets a property name.

sourcemeta::blaze::DynamicContext

struct sourcemeta::blaze::DynamicContext

The dynamic compiler context is the read-write information you have at your disposal to implement a keyword

Public Attributes
const sourcemeta::core::JSON::String &	keyword
	The schema keyword.
const sourcemeta::core::WeakPointer &	base_schema_location
	The schema base keyword path.
const sourcemeta::core::WeakPointer &	base_instance_location
	The base instance location that the keyword must be evaluated to.

sourcemeta::blaze::Tweaks

struct sourcemeta::blaze::Tweaks

Advanced knobs that you can tweak for higher control and optimisations

Public Attributes
bool	properties_always_unroll {false}
	Always unroll properties in a logical AND operation.
bool	properties_reorder {true}
	Attempt to re-order properties subschemas to evaluate cheaper ones first.
std::size_t	target_inline_threshold {50}
	Inline jump targets with fewer instructions than this threshold.
bool	format_assertion {false}
	When set, force format to be compiled as an assertion.

sourcemeta::blaze::Context

struct sourcemeta::blaze::Context

The static compiler context is the information you have at your disposal to implement a keyword that will never change throughout the compilation process

Public Attributes
const sourcemeta::core::JSON &	root
	The root schema resource.
const sourcemeta::blaze::SchemaFrame &	frame
	The reference frame of the entire schema.
const std::vector< std::string >	resources
	The set of all schema resources in the schema without duplicates.
const sourcemeta::blaze::SchemaWalker &	walker
	The schema walker in use.
const sourcemeta::blaze::SchemaResolver &	resolver
	The schema resolver in use.
const Compiler &	compiler
	The schema compiler in use.
const Mode	mode
	The mode of the schema compiler.
const bool	uses_dynamic_scopes
	Whether the schema makes use of dynamic scoping.
const SchemaUnevaluatedEntries	unevaluated
	The list of unevaluated entries and their dependencies.
const Tweaks	tweaks
	The set of tweaks for the compiler.
const std::map< std::tuple< sourcemeta::blaze::SchemaReferenceType, std::string_view, bool >, std::pair< std::size_t, const sourcemeta::core::WeakPointer * > >	targets
	All possible reference targets (key includes is_property_name context)
std::vector< InstructionExtra > &	extra
	Accumulator for instruction extra data during compilation.

sourcemeta::blaze::SchemaUnevaluatedEntry

struct sourcemeta::blaze::SchemaUnevaluatedEntry

Public Attributes
std::set< sourcemeta::core::WeakPointer >	static_dependencies
	The absolute pointers of the static keyword dependencies.
std::set< sourcemeta::core::WeakPointer >	dynamic_dependencies
	The absolute pointers of the static keyword dependencies.
bool	unresolved {false}

Member Data Documentation

unresolved

bool sourcemeta::blaze::SchemaUnevaluatedEntry::unresolved {false}

Whether the entry cannot be fully resolved, which means there might be unknown dynamic dependencies

Typedef Documentation

Compiler

using sourcemeta::blaze::Compiler = typedef std::function<Instructions(const Context &, const SchemaContext &, const DynamicContext &, const Instructions &)>

A compiler is represented as a function that maps a keyword compiler contexts into a compiler template. You can provide your own to implement your own keywords

SchemaUnevaluatedEntries

using sourcemeta::blaze::SchemaUnevaluatedEntries = typedef std::map<sourcemeta::core::JSON::String, SchemaUnevaluatedEntry>

The flattened set of unevaluated cases in the schema by absolute URI

Function Documentation

compile() [1/3]

auto sourcemeta::blaze::compile	(	const Context &	context,
		const SchemaContext &	schema_context,
		const DynamicContext &	dynamic_context,
		const sourcemeta::core::WeakPointer &	schema_suffix,
		const sourcemeta::core::WeakPointer &	instance_suffix = sourcemeta::core::empty_weak_pointer,
		std::optional< std::string_view >	uri = std::nullopt
	)		-> Instructions

This function compiles a single subschema into a compiler template as determined by the given pointer. If a URI is given, the compiler will attempt to jump to that corresponding frame entry. Otherwise, it will navigate within the current keyword. This function is not meant to be used directly, but instead as a building block for supporting applicators on compiler functions.

compile() [2/3]

auto sourcemeta::blaze::compile	(	const sourcemeta::core::JSON &	schema,
		const sourcemeta::blaze::SchemaWalker &	walker,
		const sourcemeta::blaze::SchemaResolver &	resolver,
		const Compiler &	compiler,
		const Mode	mode = Mode::FastValidation,
		const std::string_view	default_dialect = "",
		const std::string_view	default_id = "",
		const std::string_view	entrypoint = "",
		const std::optional< Tweaks > &	tweaks = std::nullopt
	)		-> Template

This function compiles an input JSON Schema into a template that can be later evaluated. For example:

#include <sourcemeta/blaze/compiler.h>
 
#include <sourcemeta/core/json.h>
#include <sourcemeta/blaze/foundation.h>
 
const sourcemeta::core::JSON schema =
    sourcemeta::core::parse_json(R"JSON({
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "type": "string"
})JSON");
 
const auto schema_template{sourcemeta::blaze::compile(
    schema, sourcemeta::blaze::schema_walker,
    sourcemeta::blaze::schema_resolver,
    sourcemeta::blaze::default_schema_compiler)};
 
// Evaluate or encode

compile() [3/3]

auto sourcemeta::blaze::compile	(	const sourcemeta::core::JSON &	schema,
		const sourcemeta::blaze::SchemaWalker &	walker,
		const sourcemeta::blaze::SchemaResolver &	resolver,
		const Compiler &	compiler,
		const sourcemeta::blaze::SchemaFrame &	frame,
		const std::string_view	entrypoint,
		const Mode	mode = Mode::FastValidation,
		const std::optional< Tweaks > &	tweaks = std::nullopt
	)		-> Template

This function compiles an input JSON Schema into a template that can be later evaluated, but given an existing schema frame. The schema frame must contain reference information for the given schema and the input schema must be bundled. If those pre-conditions are not met, you will hit undefined behavior.

Don't use this function unless you know what you are doing.

default_schema_compiler()

auto sourcemeta::blaze::default_schema_compiler	(	const Context &	,
		const SchemaContext &	,
		const DynamicContext &	,
		const Instructions &
	)		-> Instructions

A default compiler that aims to implement every keyword for official JSON Schema dialects.

to_json()

auto sourcemeta::blaze::to_json

(

const Template &

schema_template

)

-> sourcemeta::core::JSON

Serialise a template as JSON