144 lines
4.2 KiB
JavaScript
144 lines
4.2 KiB
JavaScript
/*\
|
|
title: $:/core/modules/indexers/field-indexer.js
|
|
type: application/javascript
|
|
module-type: indexer
|
|
|
|
Indexes the tiddlers with each field value
|
|
|
|
\*/
|
|
(function(){
|
|
|
|
/*jslint node: true, browser: true */
|
|
/*global modules: false */
|
|
"use strict";
|
|
|
|
var DEFAULT_MAXIMUM_INDEXED_VALUE_LENGTH = 128;
|
|
|
|
function FieldIndexer(wiki) {
|
|
this.wiki = wiki;
|
|
}
|
|
|
|
FieldIndexer.prototype.init = function() {
|
|
this.index = null;
|
|
this.maxIndexedValueLength = DEFAULT_MAXIMUM_INDEXED_VALUE_LENGTH;
|
|
this.addIndexMethods();
|
|
}
|
|
|
|
// Provided for testing
|
|
FieldIndexer.prototype.setMaxIndexedValueLength = function(length) {
|
|
this.index = null;
|
|
this.maxIndexedValueLength = length;
|
|
};
|
|
|
|
FieldIndexer.prototype.addIndexMethods = function() {
|
|
var self = this;
|
|
this.wiki.each.byField = function(name,value) {
|
|
var titles = self.wiki.allTitles(),
|
|
lookup = self.lookup(name,value);
|
|
return lookup && lookup.filter(function(title) {
|
|
return titles.indexOf(title) !== -1;
|
|
});
|
|
};
|
|
this.wiki.eachShadow.byField = function(name,value) {
|
|
var titles = self.wiki.allShadowTitles(),
|
|
lookup = self.lookup(name,value);
|
|
return lookup && lookup.filter(function(title) {
|
|
return titles.indexOf(title) !== -1;
|
|
});
|
|
};
|
|
this.wiki.eachTiddlerPlusShadows.byField = function(name,value) {
|
|
var lookup = self.lookup(name,value);
|
|
return lookup ? lookup.slice(0) : null;
|
|
};
|
|
this.wiki.eachShadowPlusTiddlers.byField = function(name,value) {
|
|
var lookup = self.lookup(name,value);
|
|
return lookup ? lookup.slice(0) : null;
|
|
};
|
|
};
|
|
|
|
/*
|
|
Tear down and then rebuild the index as if all tiddlers have changed
|
|
*/
|
|
FieldIndexer.prototype.rebuild = function() {
|
|
// Invalidate the index so that it will be rebuilt when it is next used
|
|
this.index = null;
|
|
};
|
|
|
|
/*
|
|
Build the index for a particular field
|
|
*/
|
|
FieldIndexer.prototype.buildIndexForField = function(name) {
|
|
var self = this;
|
|
// Hashmap by field name of hashmap by field value of array of tiddler titles
|
|
this.index = this.index || Object.create(null);
|
|
this.index[name] = Object.create(null);
|
|
var baseIndex = this.index[name];
|
|
// Update the index for each tiddler
|
|
this.wiki.eachTiddlerPlusShadows(function(tiddler,title) {
|
|
if(name in tiddler.fields) {
|
|
var value = tiddler.getFieldString(name);
|
|
// Skip any values above the maximum length
|
|
if(value.length < self.maxIndexedValueLength) {
|
|
baseIndex[value] = baseIndex[value] || [];
|
|
baseIndex[value].push(title);
|
|
}
|
|
}
|
|
});
|
|
};
|
|
|
|
/*
|
|
Update the index in the light of a tiddler value changing; note that the title must be identical. (Renames are handled as a separate delete and create)
|
|
updateDescriptor: {old: {tiddler: <tiddler>, shadow: <boolean>, exists: <boolean>},new: {tiddler: <tiddler>, shadow: <boolean>, exists: <boolean>}}
|
|
*/
|
|
FieldIndexer.prototype.update = function(updateDescriptor) {
|
|
var self = this;
|
|
// Don't do anything if the index hasn't been built yet
|
|
if(this.index === null) {
|
|
return;
|
|
}
|
|
// Remove the old tiddler from the index
|
|
if(updateDescriptor.old.tiddler) {
|
|
$tw.utils.each(this.index,function(indexEntry,name) {
|
|
if(name in updateDescriptor.old.tiddler.fields) {
|
|
var value = updateDescriptor.old.tiddler.getFieldString(name),
|
|
tiddlerList = indexEntry[value];
|
|
if(tiddlerList) {
|
|
var index = tiddlerList.indexOf(updateDescriptor.old.tiddler.fields.title);
|
|
if(index !== -1) {
|
|
tiddlerList.splice(index,1);
|
|
}
|
|
}
|
|
}
|
|
});
|
|
}
|
|
// Add the new tiddler to the index
|
|
if(updateDescriptor["new"].tiddler) {
|
|
$tw.utils.each(this.index,function(indexEntry,name) {
|
|
if(name in updateDescriptor["new"].tiddler.fields) {
|
|
var value = updateDescriptor["new"].tiddler.getFieldString(name);
|
|
if(value.length < self.maxIndexedValueLength) {
|
|
indexEntry[value] = indexEntry[value] || [];
|
|
indexEntry[value].push(updateDescriptor["new"].tiddler.fields.title);
|
|
}
|
|
}
|
|
});
|
|
}
|
|
};
|
|
|
|
// Lookup the given field returning a list of tiddler titles
|
|
FieldIndexer.prototype.lookup = function(name,value) {
|
|
// Fail the lookup if the value is too long
|
|
if(value.length >= this.maxIndexedValueLength) {
|
|
return null;
|
|
}
|
|
// Update the index if it has yet to be built
|
|
if(this.index === null || !this.index[name]) {
|
|
this.buildIndexForField(name);
|
|
}
|
|
return this.index[name][value] || [];
|
|
};
|
|
|
|
exports.FieldIndexer = FieldIndexer;
|
|
|
|
})();
|