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Diffstat (limited to 'mailnews/db/gloda/modules/noun_mimetype.js')
| -rw-r--r-- | mailnews/db/gloda/modules/noun_mimetype.js | 365 |
1 files changed, 365 insertions, 0 deletions
diff --git a/mailnews/db/gloda/modules/noun_mimetype.js b/mailnews/db/gloda/modules/noun_mimetype.js new file mode 100644 index 000000000..066031c4a --- /dev/null +++ b/mailnews/db/gloda/modules/noun_mimetype.js @@ -0,0 +1,365 @@ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +this.EXPORTED_SYMBOLS = ['MimeType', 'MimeTypeNoun']; + +var Cc = Components.classes; +var Ci = Components.interfaces; +var Cr = Components.results; +var Cu = Components.utils; + +Cu.import("resource:///modules/gloda/log4moz.js"); +Cu.import("resource:///modules/StringBundle.js"); + +var LOG = Log4Moz.repository.getLogger("gloda.noun.mimetype"); + +Cu.import("resource:///modules/gloda/gloda.js"); + +var CategoryStringMap = {}; + +/** + * Mime type abstraction that exists primarily so we can map mime types to + * integer id's. + * + * Instances of this class should only be retrieved via |MimeTypeNoun|; no one + * should ever create an instance directly. + */ +function MimeType(aID, aType, aSubType, aFullType, aCategory) { + this._id = aID; + this._type = aType; + this._subType = aSubType; + this._fullType = aFullType; + this._category = aCategory; +} + +MimeType.prototype = { + /** + * The integer id we have associated with the mime type. This is stable for + * the lifetime of the database, which means that anything in the Gloda + * database can use this without fear. Things not persisted in the database + * should use the actual string mime type, retrieval via |fullType|. + */ + get id() { return this._id; }, + /** + * The first part of the MIME type; "text/plain" gets you "text". + */ + get type() { return this._type; }, + set fullType(aFullType) { + if (!this._fullType) { + this._fullType = aFullType; + [this._type, this._subType] = this._fullType.split("/"); + this._category = + MimeTypeNoun._getCategoryForMimeType(aFullType, this._type); + } + }, + /** + * If the |fullType| is "text/plain", subType is "plain". + */ + get subType() { return this._subType; }, + /** + * The full MIME type; "text/plain" returns "text/plain". + */ + get fullType() { return this._fullType; }, + toString: function () { + return this.fullType; + }, + + /** + * @return the category we believe this mime type belongs to. This category + * name should never be shown directly to the user. Instead, use + * |categoryLabel| to get the localized name for the category. The + * category mapping comes from mimeTypesCategories.js. + */ + get category() { + return this._category; + }, + /** + * @return The localized label for the category from gloda.properties in the + * "gloda.mimetype.category.CATEGORY.label" definition using the value + * from |category|. + */ + get categoryLabel() { + return CategoryStringMap[this._category]; + } +}; + +/** + * Mime type noun provider. + * + * The set of MIME Types is sufficiently limited that we can keep them all in + * memory. In theory it is also sufficiently limited that we could use the + * parameter mechanism in the database. However, it is more efficient, for + * both space and performance reasons, to store the specific mime type as a + * value. For future-proofing reasons, we opt to use a database table to + * persist the mapping rather than a hard-coded list. A preferences file or + * other text file would arguably suffice, but for consistency reasons, the + * database is not a bad thing. + */ +var MimeTypeNoun = { + name: "mime-type", + clazz: MimeType, // gloda supports clazz as well as class + allowsArbitraryAttrs: false, + + _strings: new StringBundle("chrome://messenger/locale/gloda.properties"), + + // note! update test_noun_mimetype if you change our internals! + _mimeTypes: {}, + _mimeTypesByID: {}, + TYPE_BLOCK_SIZE: 16384, + _mimeTypeHighID: {}, + _mimeTypeRangeDummyObjects: {}, + _highID: 0, + + // we now use the exciting 'schema' mechanism of defineNoun to get our table + // created for us, plus some helper methods that we simply don't use. + schema: { + name: 'mimeTypes', + columns: [['id', 'INTEGER PRIMARY KEY', '_id'], + ['mimeType', 'TEXT', 'fullType']], + }, + + _init: function() { + LOG.debug("loading MIME types"); + this._loadCategoryMapping(); + this._loadMimeTypes(); + }, + + /** + * A map from MIME type to category name. + */ + _mimeTypeToCategory: {}, + /** + * Load the contents of mimeTypeCategories.js and populate + */ + _loadCategoryMapping: function MimeTypeNoun__loadCategoryMapping() { + let mimecatNS = {}; + Cu.import("resource:///modules/gloda/mimeTypeCategories.js", + mimecatNS); + let mcm = mimecatNS.MimeCategoryMapping; + + let mimeTypeToCategory = this._mimeTypeToCategory; + + function procMapObj(aSubTree, aCategories) { + for (let key in aSubTree) { + let value = aSubTree[key]; + // Add this category to our nested categories list. Use concat since + // the list will be long-lived and each list needs to be distinct. + let categories = aCategories.concat(); + categories.push(key); + + if (categories.length == 1) { + CategoryStringMap[key] = + MimeTypeNoun._strings.get( + "gloda.mimetype.category." + key + ".label"); + } + + // Is it an array? If so, just process this depth + if (Array.isArray(value)) { + for (let mimeTypeStr of value) { + mimeTypeToCategory[mimeTypeStr] = categories; + } + } + // it's yet another sub-tree branch + else { + procMapObj(value, categories); + } + } + } + + procMapObj(mimecatNS.MimeCategoryMapping, []); + }, + + /** + * Lookup the category associated with a MIME type given its full type and + * type. (So, "foo/bar" and "foo" for "foo/bar".) + */ + _getCategoryForMimeType: + function MimeTypeNoun__getCategoryForMimeType(aFullType, aType) { + if (aFullType in this._mimeTypeToCategory) + return this._mimeTypeToCategory[aFullType][0]; + let wildType = aType + "/*"; + if (wildType in this._mimeTypeToCategory) + return this._mimeTypeToCategory[wildType][0]; + return this._mimeTypeToCategory["*"][0]; + }, + + /** + * In order to allow the gloda query mechanism to avoid hitting the database, + * we need to either define the noun type as cachable and have a super-large + * cache or simply have a collection with every MIME type in it that stays + * alive forever. + * This is that collection. It is initialized by |_loadMimeTypes|. As new + * MIME types are created, we add them to the collection. + */ + _universalCollection: null, + + /** + * Kick off a query of all the mime types in our database, leaving + * |_processMimeTypes| to actually do the legwork. + */ + _loadMimeTypes: function MimeTypeNoun__loadMimeTypes() { + // get all the existing mime types! + let query = Gloda.newQuery(this.id); + let nullFunc = function() {}; + this._universalCollection = query.getCollection({ + onItemsAdded: nullFunc, onItemsModified: nullFunc, + onItemsRemoved: nullFunc, + onQueryCompleted: function (aCollection) { + MimeTypeNoun._processMimeTypes(aCollection.items); + } + }, null); + }, + + /** + * For the benefit of our Category queryHelper, we need dummy ranged objects + * that cover the numerical address space allocated to the category. We + * can't use a real object for the upper-bound because the upper-bound is + * constantly growing and there is the chance the query might get persisted, + * which means these values need to be long-lived. Unfortunately, our + * solution to this problem (dummy objects) complicates the second case, + * should it ever occur. (Because the dummy objects cannot be persisted + * on their own... but there are other issues that will come up that we will + * just have to deal with then.) + */ + _createCategoryDummies: function (aId, aCategory) { + let blockBottom = aId - (aId % this.TYPE_BLOCK_SIZE); + let blockTop = blockBottom + this.TYPE_BLOCK_SIZE - 1; + this._mimeTypeRangeDummyObjects[aCategory] = [ + new MimeType(blockBottom, "!category-dummy!", aCategory, + "!category-dummy!/" + aCategory, aCategory), + new MimeType(blockTop, "!category-dummy!", aCategory, + "!category-dummy!/" + aCategory, aCategory) + ]; + }, + + _processMimeTypes: function MimeTypeNoun__processMimeTypes(aMimeTypes) { + for (let mimeType of aMimeTypes) { + if (mimeType.id > this._highID) + this._highID = mimeType.id; + this._mimeTypes[mimeType] = mimeType; + this._mimeTypesByID[mimeType.id] = mimeType; + + let typeBlock = mimeType.id - (mimeType.id % this.TYPE_BLOCK_SIZE); + let blockHighID = (mimeType.category in this._mimeTypeHighID) ? + this._mimeTypeHighID[mimeType.category] : undefined; + // create the dummy range objects + if (blockHighID === undefined) + this._createCategoryDummies(mimeType.id, mimeType.category); + if ((blockHighID === undefined) || mimeType.id > blockHighID) + this._mimeTypeHighID[mimeType.category] = mimeType.id; + } + }, + + _addNewMimeType: function MimeTypeNoun__addNewMimeType(aMimeTypeName) { + let [typeName, subTypeName] = aMimeTypeName.split("/"); + let category = this._getCategoryForMimeType(aMimeTypeName, typeName); + + if (!(category in this._mimeTypeHighID)) { + let nextID = this._highID - (this._highID % this.TYPE_BLOCK_SIZE) + + this.TYPE_BLOCK_SIZE; + this._mimeTypeHighID[category] = nextID; + this._createCategoryDummies(nextID, category); + } + + let nextID = ++this._mimeTypeHighID[category]; + + let mimeType = new MimeType(nextID, typeName, subTypeName, aMimeTypeName, + category); + if (mimeType.id > this._highID) + this._highID = mimeType.id; + + this._mimeTypes[aMimeTypeName] = mimeType; + this._mimeTypesByID[nextID] = mimeType; + + // As great as the gloda extension mechanisms are, we don't think it makes + // a lot of sense to use them in this case. So we directly trigger object + // insertion without any of the grokNounItem stuff. + this.objInsert.call(this.datastore, mimeType); + // Since we bypass grokNounItem and its fun, we need to explicitly add the + // new MIME-type to _universalCollection ourselves. Don't try this at + // home, kids. + this._universalCollection._onItemsAdded([mimeType]); + + return mimeType; + }, + + /** + * Map a mime type to a |MimeType| instance, creating it if necessary. + * + * @param aMimeTypeName The mime type. It may optionally include parameters + * (which will be ignored). A mime type is of the form "type/subtype". + * A type with parameters would look like 'type/subtype; param="value"'. + */ + getMimeType: function MimeTypeNoun_getMimeType(aMimeTypeName) { + // first, lose any parameters + let semiIndex = aMimeTypeName.indexOf(";"); + if (semiIndex >= 0) + aMimeTypeName = aMimeTypeName.substring(0, semiIndex); + aMimeTypeName = aMimeTypeName.trim().toLowerCase(); + + if (aMimeTypeName in this._mimeTypes) + return this._mimeTypes[aMimeTypeName]; + else + return this._addNewMimeType(aMimeTypeName); + }, + + /** + * Query helpers contribute additional functions to the query object for the + * attributes that use the noun type. For example, we define Category, so + * for the "attachmentTypes" attribute, "attachmentTypesCategory" would be + * exposed. + */ + queryHelpers: { + /** + * Query for MIME type categories based on one or more MIME type objects + * passed in. We want the range to span the entire block allocated to the + * category. + * + * @param aAttrDef The attribute that is using us. + * @param aArguments The actual arguments object that + */ + Category: function(aAttrDef, aArguments) { + let rangePairs = []; + // If there are no arguments then we want to fall back to the 'in' + // constraint which matches on any attachment. + if (aArguments.length == 0) + return this._inConstraintHelper(aAttrDef, []); + + for (let iArg = 0; iArg < aArguments.length; iArg++) { + let arg = aArguments[iArg]; + rangePairs.push(MimeTypeNoun._mimeTypeRangeDummyObjects[arg.category]); + } + return this._rangedConstraintHelper(aAttrDef, rangePairs); + } + }, + + comparator: function gloda_noun_mimeType_comparator(a, b) { + if (a == null) { + if (b == null) + return 0; + else + return 1; + } + else if (b == null) { + return -1; + } + return a.fullType.localeCompare(b.fullType); + }, + + toParamAndValue: function gloda_noun_mimeType_toParamAndValue(aMimeType) { + return [null, aMimeType.id]; + }, + toJSON: function gloda_noun_mimeType_toJSON(aMimeType) { + return aMimeType.id; + }, + fromJSON: function gloda_noun_mimeType_fromJSON(aMimeTypeID) { + return this._mimeTypesByID[aMimeTypeID]; + }, +}; +Gloda.defineNoun(MimeTypeNoun, Gloda.NOUN_MIME_TYPE); +try { +MimeTypeNoun._init(); +} catch (ex) { + LOG.error("problem init-ing: " + ex.fileName + ":" + ex.lineNumber + ": " + ex); +} |