Documentation

Processor
in package

Application

Processor processes JSON-LD documents as specified by the JSON-LD specification.

Constants

CONTEXT_MAX_IRI_RECURSIONS = 10: Maximum number of recursion that are allowed to resolve an IRI
REMOTE_TIMEOUT = 10: Timeout for retrieving remote documents in seconds

Properties

$baseIri : IRI
$blankNodeCounter : int
$blankNodeMap : array<string|int, mixed>
$compactArrays : bool: Compact arrays with just one element to a scalar
$documentFactory : DocumentFactoryInterface
$documentLoader : DocumentLoaderInterface
$framingKeywords : array<string|int, mixed>
$generalizedRdf : bool: Produce generalized RDF
$keywords : array<string|int, mixed>
$optimize : bool: Optimize compacted output
$useNativeTypes : bool: Use native types when converting from RDF
$useRdfType : bool: Use rdf:type instead of \@type when converting from RDF

Methods

__construct() : mixed: Constructor
compact() : mixed: Compacts a JSON-LD document
createInverseContext() : array<string|int, mixed>: Creates an inverse context to simplify IRI compaction
expand() : mixed: Expands a JSON-LD document
flatten() : array<string|int, mixed>: Flattens a JSON-LD document
frame() : array<string|int, mixed>: Frames a JSON-LD document according a supplied frame
fromRdf() : array<string|int, mixed>: Converts an array of RDF quads to a JSON-LD document
getDocument() : Document: Parses a JSON-LD document and returns it as a Document
parse() : mixed: Parses a JSON-LD document to a PHP value
processContext() : mixed: Processes a local context to update the active context
toRdf() : array<string|int, Quad>: Converts an expanded JSON-LD document to RDF quads
addMissingNodeProperties() : mixed: Adds all properties from node to result if they haven't been added yet
compactIri() : string: Compacts an absolute IRI (or aliases a keyword)
compactValue() : mixed: Compacts a value
createListObjects() : mixed: Reconstruct @list arrays from linked list structures
elementToRdf() : IRI|TypedValue|LanguageTagged|null: Converts a JSON-LD element to a RDF Quad object
expandIri() : string: Expands a JSON-LD IRI value (term, compact IRI, IRI) to an absolute IRI and relabels blank nodes
expandKeywordValue() : mixed: Expands the value of a keyword
expandValue() : stdClass: Expands a scalar value
generateNodeMap() : mixed: Creates a node map of an expanded JSON-LD document
getBlankNodeId() : string: Generate a new blank node identifier
getPropertyDefinition() : array<string|int, mixed>|string|null: Returns a property's definition
getValueProfile() : array<string|int, mixed>: Calculates a value profile
hasNodeProperties() : bool: Checks whether a node has properties and not just an @id
listToRdf() : IRI: Converts a JSON-LD list to a linked RDF list (quads)
loadDocument() : mixed: Load a JSON-LD document
mergeIntoProperty() : mixed: Merges a value into a property of an object
nodeMatchesFrame() : bool: Checks whether a node matches a frame or not.
objectToJsonLd() : mixed: Converts an object to a JSON-LD representation
queryInverseContext() : null|string: Queries the inverse context to find the term for a given query path (= value profile)
setProperty() : mixed: Adds a property to an object if it doesn't exist yet
sortTerms() : int: Compares two values by their length and then lexicographically
subtreeEquals() : bool: Verifies whether two JSON-LD subtrees are equal not

CONTEXT_MAX_IRI_RECURSIONS

Maximum number of recursion that are allowed to resolve an IRI


    public
        mixed
    CONTEXT_MAX_IRI_RECURSIONS
    = 10

REMOTE_TIMEOUT

Timeout for retrieving remote documents in seconds


    public
        mixed
    REMOTE_TIMEOUT
    = 10

$baseIri


    private
        IRI
    $baseIri
     = null

The base IRI

$blankNodeCounter


    private
        int
    $blankNodeCounter
     = 0

Blank node counter

$blankNodeMap


    private
        array<string|int, mixed>
    $blankNodeMap
     = array()

Blank node map

$compactArrays

Compact arrays with just one element to a scalar


    private
        bool
    $compactArrays

If set to true, arrays holding just one element are compacted to scalars, otherwise the arrays are kept as arrays.

$documentFactory


    private
        DocumentFactoryInterface
    $documentFactory
     = null

The factory to create new documents

$documentLoader


    private
        DocumentLoaderInterface
    $documentLoader
     = null

The document loader

$framingKeywords


    private
    static    array<string|int, mixed>
    $framingKeywords
     = array(
    '@explicit',
    '@default',
    '@embed',
    //'@omitDefault',     // TODO Is this really needed?
    '@embedChildren',
)

Framing options keywords

$generalizedRdf

Produce generalized RDF


    private
        bool
    $generalizedRdf

Unless set to true, triples/quads with a blank node predicate are dropped when converting to RDF.

$keywords


    private
    static    array<string|int, mixed>
    $keywords
     = array('@context', '@id', '@value', '@language', '@type', '@container', '@list', '@set', '@graph', '@reverse', '@base', '@vocab', '@index', '@null')

A list of all defined keywords

$optimize

Optimize compacted output


    private
        bool
    $optimize

If set to true, the processor is free to optimize the result to produce an even compacter representation than the algorithm described by the official JSON-LD specification.

$useNativeTypes

Use native types when converting from RDF


    private
        bool
    $useNativeTypes

If set to true, the processor will try to convert datatyped literals to native types instead of using the expanded object form when converting from RDF. xsd:boolean values will be converted to booleans whereas xsd:integer and xsd:double values will be converted to numbers.

$useRdfType

Use rdf:type instead of \@type when converting from RDF


    private
        bool
    $useRdfType

If set to true, the JSON-LD processor will use the expanded rdf:type IRI as the property instead of @type when converting from RDF.

__construct()

Constructor


    public
                    __construct(stdClass $options) : mixed

The options parameter must be passed and all off the following properties have to be set:

The base IRI.
If set to true, arrays holding just one element are compacted to scalars, otherwise the arrays are kept as arrays.
If set to true, the processor is free to optimize the result to produce an even compacter representation than the algorithm described by the official JSON-LD specification.
If set to true, the processor will try to convert datatyped literals to native types instead of using the expanded object form when converting from RDF. xsd:boolean values will be converted to booleans whereas xsd:integer and xsd:double values will be converted to numbers.
If set to true, the JSON-LD processor will use the expanded rdf:type IRI as the property instead of @type when converting from RDF.

Parameters

$options : stdClass: Options to configure the various algorithms.

compact()

Compacts a JSON-LD document


    public
                    compact(mixed &$element[, array<string|int, mixed> $activectx = array() ][, array<string|int, mixed> $inversectx = array() ][, null|string $activeprty = null ]) : mixed

Attention: This method must be called with an expanded element, otherwise it might not work.

Parameters

$element : mixed: A JSON-LD element to be compacted.
$activectx : array<string|int, mixed> = array(): The active context.
$inversectx : array<string|int, mixed> = array(): The inverse context.
$activeprty : null|string = null: The active property.

Return values

mixed —

The compacted JSON-LD document.

createInverseContext()

Creates an inverse context to simplify IRI compaction


    public
                    createInverseContext(array<string|int, mixed> $activectx) : array<string|int, mixed>

The inverse context is a multidimensional array that has the following shape:


[container|@null|term]
  [@type|@language][typeIRI|languageCode]
  [@null][@null]
      [term|propGen]
          [ array of terms ]

Parameters

$activectx : array<string|int, mixed>: The active context.

Return values

array<string|int, mixed> —

The inverse context.

expand()

Expands a JSON-LD document


    public
                    expand(mixed &$element[, array<string|int, mixed> $activectx = array() ][, null|string $activeprty = null ][, bool $frame = false ]) : mixed

Parameters

$element : mixed: A JSON-LD element to be expanded.
$activectx : array<string|int, mixed> = array(): The active context.
$activeprty : null|string = null: The active property.
$frame : bool = false: True if a frame is being expanded, otherwise false.

Return values

mixed —

The expanded document.

flatten()

Flattens a JSON-LD document


    public
                    flatten(mixed $element) : array<string|int, mixed>

Parameters

$element : mixed: A JSON-LD element to be flattened.

Return values

array<string|int, mixed> —

An array representing the flattened element.

frame()

Frames a JSON-LD document according a supplied frame


    public
                    frame(array<string|int, mixed>|stdClass $element, mixed $frame) : array<string|int, mixed>

Parameters

$element : array<string|int, mixed>|stdClass: A JSON-LD element to be framed.
$frame : mixed: The frame.

Return values

array<string|int, mixed> —

$result The framed element in expanded form.

fromRdf()

Converts an array of RDF quads to a JSON-LD document


    public
                    fromRdf(array<string|int, Quad> $quads) : array<string|int, mixed>

The resulting JSON-LD document will be in expanded form.

Parameters

$quads : array<string|int, Quad>: The quads to convert

Return values

array<string|int, mixed> —

The JSON-LD document.

getDocument()

Parses a JSON-LD document and returns it as a Document


    public
                    getDocument(array<string|int, mixed>|stdClass $input) : Document

Parameters

$input : array<string|int, mixed>|stdClass: The JSON-LD document to process.

Return values

Document —

The parsed JSON-LD document.

parse()

Parses a JSON-LD document to a PHP value


    public
            static        parse(string $document) : mixed

Parameters

$document : string: A JSON-LD document.

Return values

mixed —

A PHP value.

processContext()

Processes a local context to update the active context


    public
                    processContext(mixed $loclctx, array<string|int, mixed> &$activectx[, array<string|int, mixed> $remotectxs = array() ]) : mixed

Parameters

$loclctx : mixed: The local context.
$activectx : array<string|int, mixed>: The active context.
$remotectxs : array<string|int, mixed> = array(): The already included remote contexts.

toRdf()

Converts an expanded JSON-LD document to RDF quads


    public
                    toRdf(array<string|int, mixed> $document) : array<string|int, Quad>

The result is an array of Quads.

Parameters

$document : array<string|int, mixed>: The expanded JSON-LD document to be transformed into quads.

Return values

array<string|int, Quad> —

The extracted quads.

addMissingNodeProperties()

Adds all properties from node to result if they haven't been added yet


    private
                    addMissingNodeProperties(stdClass $node, stdClass $options, stdClass $nodeMap, string $graph, stdClass &$result, array<string|int, mixed> $path) : mixed

Parameters

$node : stdClass: The node whose properties should processed.
$options : stdClass: The current framing options.
$nodeMap : stdClass: The node map.
$graph : string: The currently used graph.
$result : stdClass: The object to which the properties should be added.
$path : array<string|int, mixed>: The path of already processed nodes.

compactIri()

Compacts an absolute IRI (or aliases a keyword)


    private
                    compactIri(mixed $iri, array<string|int, mixed> $activectx, array<string|int, mixed> $inversectx[, mixed $value = null ][, bool $vocabRelative = false ][, bool $reverse = false ]) : string

If the IRI couldn't be compacted, the IRI is returned as is.

Parameters

$iri : mixed: The IRI to be compacted.
$activectx : array<string|int, mixed>: The active context.
$inversectx : array<string|int, mixed>: The inverse context.
$value : mixed = null: The value of the property to compact.
$vocabRelative : bool = false: If true is passed, this method tries to convert the IRI to an IRI relative to @vocab; otherwise, that fall back mechanism is disabled.
$reverse : bool = false: Is the IRI used within a @reverse container?

Return values

string —

Returns the compacted IRI on success; otherwise the IRI is returned as is.

compactValue()

Compacts a value


    private
                    compactValue(mixed $value, array<string|int, mixed> $definition, array<string|int, mixed> $activectx, array<string|int, mixed> $inversectx) : mixed

The passed property definition must be an associative array containing the following data:



        Parameters
    
                    
                $value
                : mixed
                            
            
                    The value to compact (arrays are not allowed!).


            
                    
                $definition
                : array<string|int, mixed>
                            
            
                    The active property's definition.


            
                    
                $activectx
                : array<string|int, mixed>
                            
            
                    The active context.


            
                    
                $inversectx
                : array<string|int, mixed>
                            
            
                    The inverse context.


            
            

    
    
        Tags

type

Return values

mixed —

The compacted value.

createListObjects()

Reconstruct @list arrays from linked list structures


    private
                    createListObjects(stdClass $graphs, stdClass $usages) : mixed

Parameters

$graphs : stdClass: The graph map
$usages : stdClass: The global node usage map

elementToRdf()

Converts a JSON-LD element to a RDF Quad object


    private
                    elementToRdf(stdClass $element) : IRI|TypedValue|LanguageTagged|null

Parameters

$element : stdClass: The element to be converted.

Return values

IRI|TypedValue|LanguageTagged|null —

The converted element to be used as Quad object.

expandIri()

Expands a JSON-LD IRI value (term, compact IRI, IRI) to an absolute IRI and relabels blank nodes


    private
                    expandIri(mixed $value, array<string|int, mixed> $activectx[, bool $relativeIri = false ][, bool $vocabRelative = false ][, null|stdClass $localctx = null ][, array<string|int, mixed> $path = array() ]) : string

Parameters

$value : mixed: The value to be expanded to an absolute IRI.
$activectx : array<string|int, mixed>: The active context.
$relativeIri : bool = false: Specifies whether $value should be treated as relative IRI against the base IRI or not.
$vocabRelative : bool = false: Specifies whether $value is relative to @vocab if set or not.
$localctx : null|stdClass = null: If the IRI is being expanded as part of context processing, the current local context has to be passed as well.
$path : array<string|int, mixed> = array(): A path of already processed terms to detect circular dependencies

Return values

string —

The expanded IRI.

expandKeywordValue()

Expands the value of a keyword


    private
                    expandKeywordValue(stdClass &$element, string $activeprty, string $keyword, mixed $value, array<string|int, mixed> $activectx, bool $frame) : mixed

Parameters

$element : stdClass: The object this property-value pair is part of.
$activeprty : string: The active property.
$keyword : string: The keyword whose value is being expanded.
$value : mixed: The value to expand.
$activectx : array<string|int, mixed>: The active context.
$frame : bool: True if a frame is being expanded, otherwise false.

expandValue()

Expands a scalar value


    private
                    expandValue(mixed $value, array<string|int, mixed> $activectx, string $activeprty) : stdClass

Parameters

$value : mixed: The value to expand.
$activectx : array<string|int, mixed>: The active context.
$activeprty : string: The active property.

Return values

stdClass —

The expanded value.

generateNodeMap()

Creates a node map of an expanded JSON-LD document


    private
                    generateNodeMap(stdClass &$nodeMap, stdClass|array<string|int, stdClass> $element[, string $activegraph = JsonLD::DEFAULT_GRAPH ][, null|string $activeid = null ][, null|string $activeprty = null ][, null|stdClass &$list = null ]) : mixed

All keys in the node map are prefixed with "-" to support empty strings.

Parameters

$nodeMap : stdClass: The object holding the node map.
$element : stdClass|array<string|int, stdClass>: An expanded JSON-LD element to be put into the node map
$activegraph : string = JsonLD::DEFAULT_GRAPH: The graph currently being processed.
$activeid : null|string = null: The node currently being processed.
$activeprty : null|string = null: The property currently being processed.
$list : null|stdClass = null: The list object if a list is being processed.

getBlankNodeId()

Generate a new blank node identifier


    private
                    getBlankNodeId([null|string $id = null ]) : string

If an identifier is passed, a new blank node identifier is generated for it and stored for subsequent use. Calling the method with the same identifier (except null) will thus always return the same blank node identifier.

Parameters

$id : null|string = null: If available, existing blank node identifier.

Return values

string —

Returns a blank node identifier.

getPropertyDefinition()

Returns a property's definition


    private
                    getPropertyDefinition(array<string|int, mixed> $activectx, string $property[, null|string $only = null ]) : array<string|int, mixed>|string|null

The result will be in the form


  array('@type'      => type or null,
        '@language'  => language or null,
        '@container' => container or null,
        'isKeyword'  => true or false)

If $only is set, only the value of that key of the array above will be returned.

Parameters

$activectx : array<string|int, mixed>: The active context.
$property : string: The property.
$only : null|string = null: If set, only this element of the definition will be returned.

Return values

array<string|int, mixed>|string|null —

Returns either the property's definition or null if not found.

getValueProfile()

Calculates a value profile


    private
                    getValueProfile(stdClass $value, array<string|int, mixed> $inversectx) : array<string|int, mixed>

A value profile represent the schema of the value ignoring the concrete value. It is an associative array containing the following keys-value pairs:

@container: the container, defaults to @set
typeLang: is set to @type for typed values or @language for (language-tagged) strings; for all other values it is set to null
typeLangValue: set to the type of a typed value or the language of a language-tagged string (@null for all other strings); for all other values it is set to null

Parameters

$value : stdClass: The value.
$inversectx : array<string|int, mixed>: The inverse context.

Return values

array<string|int, mixed> —

The value profile.

hasNodeProperties()

Checks whether a node has properties and not just an @id


    private
                    hasNodeProperties(stdClass $node) : bool

This is used to filter nodes consisting just of an @id-member when flattening and converting from RDF.

Parameters

$node : stdClass: The node

Return values

bool —

True if the node has properties (other than @id), false otherwise.

listToRdf()

Converts a JSON-LD list to a linked RDF list (quads)


    private
                    listToRdf(array<string|int, mixed> $entries, array<string|int, mixed> &$quads[, null|IRI $graph = null ]) : IRI

Parameters

$entries : array<string|int, mixed>: The list entries
$quads : array<string|int, mixed>: The array to be used to hold the linked list
$graph : null|IRI = null: The graph to be used in the constructed Quads

Return values

IRI —

Returns the IRI of the head of the list

loadDocument()

Load a JSON-LD document


    private
                    loadDocument(null|string|array<string|int, mixed>|stdClass $input) : mixed

The document can be supplied directly as string, by passing a file path, or by passing a URL.

Parameters

$input : null|string|array<string|int, mixed>|stdClass: The JSON-LD document or a path or URL pointing to one.

Return values

mixed —

The loaded JSON-LD document

mergeIntoProperty()

Merges a value into a property of an object


    private
            static        mergeIntoProperty(stdClass &$object, string $property, mixed $value[, bool $alwaysArray = false ][, bool $unique = false ]) : mixed

Parameters

$object : stdClass: The object.
$property : string: The name of the property to which the value should be merged into.
$value : mixed: The value to merge into the property.
$alwaysArray : bool = false: If set to true, the resulting property will always be an array.
$unique : bool = false: If set to true, the value is only added if it doesn't exist yet.

nodeMatchesFrame()

Checks whether a node matches a frame or not.


    private
                    nodeMatchesFrame(stdClass $node, null|stdClass $frame, stdClass $options, stdClass $nodeMap, string $graph, array<string|int, mixed> &$parent[, array<string|int, mixed> $path = array() ]) : bool

Parameters

$node : stdClass: The node.
$frame : null|stdClass: The frame.
$options : stdClass: The current framing options.
$nodeMap : stdClass: The node map.
$graph : string: The currently used graph.
$parent : array<string|int, mixed>: The parent to which matching results should be added.
$path : array<string|int, mixed> = array(): The path of already processed nodes.

Return values

bool —

Returns true if the node matches the frame, otherwise false.

objectToJsonLd()

Converts an object to a JSON-LD representation


    private
            static        objectToJsonLd(stdClass $object[, bool $useNativeTypes = true ]) : mixed

Only IRIs, language-tagged strings, and typed values are converted by this method. All other objects are returned as-is.

Parameters

$object : stdClass: The object to convert.
$useNativeTypes : bool = true: If set to true, native types are used for xsd:integer, xsd:double, and xsd:boolean, otherwise typed strings will be used instead.

Return values

mixed —

The JSON-LD representation of the object.

queryInverseContext()

Queries the inverse context to find the term for a given query path (= value profile)


    private
                    queryInverseContext(array<string|int, mixed> $inversectx, array<string|int, string> $containers, array<string|int, string> $typeOrLangs, array<string|int, string> $typeOrLangValues) : null|string

Parameters

$inversectx : array<string|int, mixed>: The inverse context (or a subtree thereof)
$containers : array<string|int, string>
$typeOrLangs : array<string|int, string>
$typeOrLangValues : array<string|int, string>

Return values

null|string —

The best matching term or null if none was found.

setProperty()

Adds a property to an object if it doesn't exist yet


    private
            static        setProperty(stdClass &$object, string $property, mixed $value[, mixed $errorCode = null ]) : mixed

If the property already exists, an exception is thrown as otherwise the existing value would be lost.

Parameters

$object : stdClass: The object.
$property : string: The name of the property.
$value : mixed: The value of the property.
$errorCode : mixed = null

sortTerms()

Compares two values by their length and then lexicographically


    private
            static        sortTerms(mixed $a, mixed $b) : int

If two strings have different lengths, the shorter one will be considered less than the other. If they have the same length, they are compared lexicographically.

Parameters

$a : mixed: Value A.
$b : mixed: Value B.

Return values

int —

If value A is shorter than value B, -1 will be returned; if it's longer 1 will be returned. If both values have the same length and value A is considered lexicographically less, -1 will be returned, if they are equal 0 will be returned, otherwise 1 will be returned.

subtreeEquals()

Verifies whether two JSON-LD subtrees are equal not


    private
            static        subtreeEquals(mixed $a, mixed $b) : bool

Please note that two unlabeled blank nodes will never be equal by definition.

Parameters

$a : mixed: The first subtree.
$b : mixed: The second subree.

Return values

bool —

Returns true if the two subtrees are equal; otherwise false.

Processor in package Application

Tags

Table of Contents

Constants

Properties

Methods

Constants

CONTEXT_MAX_IRI_RECURSIONS

REMOTE_TIMEOUT

Properties

$baseIri

$blankNodeCounter

$blankNodeMap

$compactArrays

$documentFactory

$documentLoader

$framingKeywords

$generalizedRdf

$keywords

$optimize

$useNativeTypes

$useRdfType

Methods

__construct()

Parameters

compact()

Parameters

Return values

createInverseContext()

Parameters

Return values

expand()

Parameters

Tags

Return values

flatten()

Parameters

Return values

frame()

Parameters

Tags

Return values

fromRdf()

Parameters

Tags

Return values

getDocument()

Parameters

Tags

Return values

parse()

Parameters

Tags

Return values

processContext()

Parameters

Tags

toRdf()

Parameters

Return values

addMissingNodeProperties()

Parameters

compactIri()

Parameters

Return values

compactValue()

Parameters

Tags

Return values

createListObjects()

Parameters

elementToRdf()

Parameters

Return values

expandIri()

Parameters

Return values

expandKeywordValue()

Parameters

Tags

Processor
in package

Application