lib6/graph-types.js
import { stringify } from './json';
const IDENTIFIER_PROPERTY_ATTRIBUTES = {
value: true,
enumerable: false,
configurable: false,
writable: false
};
const NODE_IDENTIFIER_PROPERTY = '__isNode__';
const RELATIONSHIP_IDENTIFIER_PROPERTY = '__isRelationship__';
const UNBOUND_RELATIONSHIP_IDENTIFIER_PROPERTY = '__isUnboundRelationship__';
const PATH_IDENTIFIER_PROPERTY = '__isPath__';
const PATH_SEGMENT_IDENTIFIER_PROPERTY = '__isPathSegment__';
function hasIdentifierProperty(obj, property) {
return obj != null && obj[property] === true;
}
/**
* Class for Node Type.
*/
class Node {
/**
* @constructor
* @protected
* @param {NumberOrInteger} identity - Unique identity
* @param {Array<string>} labels - Array for all labels
* @param {Properties} properties - Map with node properties
* @param {string} elementId - Node element identifier
*/
constructor(identity, labels, properties, elementId) {
/**
* Identity of the node.
* @type {NumberOrInteger}
* @deprecated use {@link Node#elementId} instead
*/
this.identity = identity;
/**
* Labels of the node.
* @type {string[]}
*/
this.labels = labels;
/**
* Properties of the node.
* @type {Properties}
*/
this.properties = properties;
/**
* The Node element identifier.
* @type {string}
*/
this.elementId = _valueOrGetDefault(elementId, () => identity.toString());
}
/**
* @ignore
*/
toString() {
let s = '(' + this.elementId;
for (let i = 0; i < this.labels.length; i++) {
s += ':' + this.labels[i];
}
const keys = Object.keys(this.properties);
if (keys.length > 0) {
s += ' {';
for (let i = 0; i < keys.length; i++) {
if (i > 0)
s += ',';
s += keys[i] + ':' + stringify(this.properties[keys[i]]);
}
s += '}';
}
s += ')';
return s;
}
}
Object.defineProperty(Node.prototype, NODE_IDENTIFIER_PROPERTY, IDENTIFIER_PROPERTY_ATTRIBUTES);
/**
* Test if given object is an instance of {@link Node} class.
* @param {Object} obj the object to test.
* @return {boolean} `true` if given object is a {@link Node}, `false` otherwise.
*/
function isNode(obj) {
return hasIdentifierProperty(obj, NODE_IDENTIFIER_PROPERTY);
}
/**
* Class for Relationship Type.
*/
class Relationship {
/**
* @constructor
* @protected
* @param {NumberOrInteger} identity - Unique identity
* @param {NumberOrInteger} start - Identity of start Node
* @param {NumberOrInteger} end - Identity of end Node
* @param {string} type - Relationship type
* @param {Properties} properties - Map with relationship properties
* @param {string} elementId - Relationship element identifier
* @param {string} startNodeElementId - Start Node element identifier
* @param {string} endNodeElementId - End Node element identifier
*/
constructor(identity, start, end, type, properties, elementId, startNodeElementId, endNodeElementId) {
/**
* Identity of the relationship.
* @type {NumberOrInteger}
* @deprecated use {@link Relationship#elementId} instead
*/
this.identity = identity;
/**
* Identity of the start node.
* @type {NumberOrInteger}
* @deprecated use {@link Relationship#startNodeElementId} instead
*/
this.start = start;
/**
* Identity of the end node.
* @type {NumberOrInteger}
* @deprecated use {@link Relationship#endNodeElementId} instead
*/
this.end = end;
/**
* Type of the relationship.
* @type {string}
*/
this.type = type;
/**
* Properties of the relationship.
* @type {Properties}
*/
this.properties = properties;
/**
* The Relationship element identifier.
* @type {string}
*/
this.elementId = _valueOrGetDefault(elementId, () => identity.toString());
/**
* The Start Node element identifier.
* @type {string}
*/
this.startNodeElementId = _valueOrGetDefault(startNodeElementId, () => start.toString());
/**
* The End Node element identifier.
* @type {string}
*/
this.endNodeElementId = _valueOrGetDefault(endNodeElementId, () => end.toString());
}
/**
* @ignore
*/
toString() {
let s = '(' + this.startNodeElementId + ')-[:' + this.type;
const keys = Object.keys(this.properties);
if (keys.length > 0) {
s += ' {';
for (let i = 0; i < keys.length; i++) {
if (i > 0)
s += ',';
s += keys[i] + ':' + stringify(this.properties[keys[i]]);
}
s += '}';
}
s += ']->(' + this.endNodeElementId + ')';
return s;
}
}
Object.defineProperty(Relationship.prototype, RELATIONSHIP_IDENTIFIER_PROPERTY, IDENTIFIER_PROPERTY_ATTRIBUTES);
/**
* Test if given object is an instance of {@link Relationship} class.
* @param {Object} obj the object to test.
* @return {boolean} `true` if given object is a {@link Relationship}, `false` otherwise.
*/
function isRelationship(obj) {
return hasIdentifierProperty(obj, RELATIONSHIP_IDENTIFIER_PROPERTY);
}
/**
* Class for UnboundRelationship Type.
* @access private
*/
class UnboundRelationship {
/**
* @constructor
* @protected
* @param {NumberOrInteger} identity - Unique identity
* @param {string} type - Relationship type
* @param {Properties} properties - Map with relationship properties
* @param {string} elementId - Relationship element identifier
*/
constructor(identity, type, properties, elementId) {
/**
* Identity of the relationship.
* @type {NumberOrInteger}
* @deprecated use {@link UnboundRelationship#elementId} instead
*/
this.identity = identity;
/**
* Type of the relationship.
* @type {string}
*/
this.type = type;
/**
* Properties of the relationship.
* @type {Properties}
*/
this.properties = properties;
/**
* The Relationship element identifier.
* @type {string}
*/
this.elementId = _valueOrGetDefault(elementId, () => identity.toString());
}
/**
* Bind relationship
*
* @protected
* @deprecated use {@link UnboundRelationship#bindTo} instead
* @param {Integer} start - Identity of start node
* @param {Integer} end - Identity of end node
* @return {Relationship} - Created relationship
*/
bind(start, end) {
return new Relationship(this.identity, start, end, this.type, this.properties, this.elementId);
}
/**
* Bind relationship
*
* @protected
* @param {Node} start - Start Node
* @param {Node} end - End Node
* @return {Relationship} - Created relationship
*/
bindTo(start, end) {
return new Relationship(this.identity, start.identity, end.identity, this.type, this.properties, this.elementId, start.elementId, end.elementId);
}
/**
* @ignore
*/
toString() {
let s = '-[:' + this.type;
const keys = Object.keys(this.properties);
if (keys.length > 0) {
s += ' {';
for (let i = 0; i < keys.length; i++) {
if (i > 0)
s += ',';
s += keys[i] + ':' + stringify(this.properties[keys[i]]);
}
s += '}';
}
s += ']->';
return s;
}
}
Object.defineProperty(UnboundRelationship.prototype, UNBOUND_RELATIONSHIP_IDENTIFIER_PROPERTY, IDENTIFIER_PROPERTY_ATTRIBUTES);
/**
* Test if given object is an instance of {@link UnboundRelationship} class.
* @param {Object} obj the object to test.
* @return {boolean} `true` if given object is a {@link UnboundRelationship}, `false` otherwise.
*/
function isUnboundRelationship(obj) {
return hasIdentifierProperty(obj, UNBOUND_RELATIONSHIP_IDENTIFIER_PROPERTY);
}
/**
* Class for PathSegment Type.
*/
class PathSegment {
/**
* @constructor
* @protected
* @param {Node} start - start node
* @param {Relationship} rel - relationship that connects start and end node
* @param {Node} end - end node
*/
constructor(start, rel, end) {
/**
* Start node.
* @type {Node}
*/
this.start = start;
/**
* Relationship.
* @type {Relationship}
*/
this.relationship = rel;
/**
* End node.
* @type {Node}
*/
this.end = end;
}
}
Object.defineProperty(PathSegment.prototype, PATH_SEGMENT_IDENTIFIER_PROPERTY, IDENTIFIER_PROPERTY_ATTRIBUTES);
/**
* Test if given object is an instance of {@link PathSegment} class.
* @param {Object} obj the object to test.
* @return {boolean} `true` if given object is a {@link PathSegment}, `false` otherwise.
*/
function isPathSegment(obj) {
return hasIdentifierProperty(obj, PATH_SEGMENT_IDENTIFIER_PROPERTY);
}
/**
* Class for Path Type.
*/
class Path {
/**
* @constructor
* @protected
* @param {Node} start - start node
* @param {Node} end - end node
* @param {Array<PathSegment>} segments - Array of Segments
*/
constructor(start, end, segments) {
/**
* Start node.
* @type {Node}
*/
this.start = start;
/**
* End node.
* @type {Node}
*/
this.end = end;
/**
* Segments.
* @type {Array<PathSegment>}
*/
this.segments = segments;
/**
* Length of the segments.
* @type {Number}
*/
this.length = segments.length;
}
}
Object.defineProperty(Path.prototype, PATH_IDENTIFIER_PROPERTY, IDENTIFIER_PROPERTY_ATTRIBUTES);
/**
* Test if given object is an instance of {@link Path} class.
* @param {Object} obj the object to test.
* @return {boolean} `true` if given object is a {@link Path}, `false` otherwise.
*/
function isPath(obj) {
return hasIdentifierProperty(obj, PATH_IDENTIFIER_PROPERTY);
}
function _valueOrGetDefault(value, getDefault) {
return value === undefined || value === null ? getDefault() : value;
}
export { Node, isNode, Relationship, isRelationship, UnboundRelationship, isUnboundRelationship, Path, isPath, PathSegment, isPathSegment };