tag-tracker

Manager for associating tags with objects and quickly querying objects that match a set of tags or boolean operations with tags.

Use

import { TagTracker, compileExpression } from '@gov.nasa.jpl.honeycomb/tag-tracker';

// Add tags
const objA = {};
const objB = {};
tagTracker.addTag(objA, ['tag-a', 'tab-b']);
tagTracker.addTag(objB, ['tag-b', 'tab-c']);

// Get the objects with the given tags
tagTracker.getObjects('tag-b && !tag-c');

// or

const expr = compileExpression('tag-b && !tag-c');
tagTracker.getObjects(expr);

API

Functions

compileExpression

compileExpression( expression : String ) : Function

Prebuilds the expression evaluation function to use with the getObjects function. This can be faster than building the function on the fly.

TagTracker

Class for adding, tracking, and querying sets of tags on objects.

extends EventDispatcher

addTag

addTag( obj : Object, tag : String | Array<String> ) : Boolean

Associates a tag or set of tags with an object.

Returns true for a tag if it was added successfully or false if the tag was already associated with an object.

!> Tags cannot contain character that may be included in an expression or white, including !, &, <, >, |, =, or ~.

removeTag

removeTag( obj : Object, tag : String | Array<String> ) : Boolean

Removes a tag or st of tags from an object.

Returns true for a tag if it was removed successfully or false if the tag wasn't already associated with an object.

hasTag

hasTag( obj : Object, tag : String ) : Boolean

Returns true if the object has the given tag.

filter

filter(
	obj : Object | Array<Object>, 
	tagOrExp : String | Function, 
	flatten : Boolean = false
) : Array<Object>

Filters the given tree of objects to a flattened list of objects if flatten is true. obj is expected to have an array of children on it if flatten is true.

Returns the filtered result.

getObjects

getObjects( tagOrExp : String | Function ) : Array<Object> | null

Returns the set of objects that matches the given tag or expression. An expression may be a string or pre-compoiled expression function. For example:

tracker.getObjects('tag-a && tag-b && !tag-c || tag-d');

If the expression is null then all objects are returned.

getTags

getTags( obj : Object ) : Array<String>

Returns the set of tags associated with an object. Returns null if there are no tags.

removeObject

removeObject( obj : Object ) : void

Remove an object an all associated tags from the tracker.

getAllTags

getAllTags(  ) : Array<String>

Returns an array of all currently tracked tag names