diffusion/src/node_modules/topics/path-selector.js

Diffusion JavaScript client

var inherits = require('inherits');
var utils = require('topics/topic-path-utils');
var TopicSelector = require('../../selectors/topic-selector');

var DQ = utils.DescendantQualifier;

function TopicPathSelector(components) {
    var remainder = components.remainder;

    if (components.type === TopicSelector.Type.PATH) {
        if (components.prefix === "") {
            throw new Error("Topic path must have at least one part: " + remainder);
        }

        if (components.prefix.indexOf("//") > -1) {
            throw new Error("Topic path contains empty part: " + remainder);
        }
    }

    this.qualifier = components.qualifier;
    this.path = components.prefix;

    TopicSelector.call(
        this,
        components.type,
        components.prefix,
        components.expression);
}

inherits(TopicPathSelector, TopicSelector);

TopicPathSelector.prototype.doSelects = function (topicPath) {
    var match = this.path === topicPath;
    var descendants = topicPath.indexOf(this.path + '/') === 0;

    switch (this.qualifier) {
        case DQ.MATCH :
            return match;
        case DQ.DESCENDANTS_OF_MATCH :
            return descendants;
        case DQ.MATCH_AND_DESCENDANTS :
            return match || descendants;
        default :
            return false;
    }
};

module.exports = TopicPathSelector;