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@x5e/gink

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an eventually consistent database

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"use strict"; Object.defineProperty(exports, "__esModule", { value: true }); exports.KeySet = void 0; const Database_1 = require("./Database"); const Container_1 = require("./Container"); const utils_1 = require("./utils"); const factories_1 = require("./factories"); const builders_1 = require("./builders"); class KeySet extends Container_1.Container { constructor(database, address, containerBuilder) { super(database, address, builders_1.Behavior.KEY_SET); } static get(database, muid) { database = database || Database_1.Database.recent; if (!muid) { muid = { timestamp: -1, medallion: -1, offset: builders_1.Behavior.KEY_SET }; } return new KeySet(database, muid); } static async create(database, meta) { database = database || Database_1.Database.recent; const muid = await Container_1.Container.addContainer({ behavior: builders_1.Behavior.KEY_SET, database, meta, }); return new KeySet(database, muid); } /** * Adds a key to the keyset. * If a bundler is supplied, the function will add the entry to that bundler * and return immediately (presumably you know what to do with a CS if you passed it in). * If the caller does not supply a bundler, then one is created on the fly, and * then this method will await on the CS being added to the database instance. * This is to allow simple console usage like: * await myKeySet.add("foo"); * @param key * @param change an optional bundler to put this in. * @returns a promise that resolves to the address of the newly created entry */ async add(key, meta) { return await this.addEntry(key, Container_1.Container.INCLUSION, meta); } /** * Similar to add method, but for multiple entries. * @param keys an iterable of keys to add to the key set * @param change an optional bundler to put this in. * @returns a promise that resolves to a Bundler object for the created entries. */ async update(keys, meta) { let bundler = await this.database.startBundle(meta); for (const key of keys) { await this.addEntry(key, Container_1.Container.INCLUSION, { bundler }); } if (!meta?.bundler) { await bundler.commit(); } } /** * Adds a deletion marker (tombstone) for a particular key in the directory. * The corresponding value will be seen to be unset in the data model. * @param key * @param change an optional bundler to put this in. * @returns a promise that resolves to the address of the newly created deletion entry */ async delete(key, meta) { return await this.addEntry(key, Container_1.Container.DELETION, meta); } /** * Function to iterate over the contents of the key set. * @param asOf * @returns an async iterator across everything in the key set, with values returned as pairs of Key, Key */ entries(asOf) { const thisSet = this; return (async function* () { const entries = await thisSet.database.store.getKeyedEntries(thisSet.address, asOf); for (const [key, entry] of entries) { const storageKey = entry.storageKey; yield [storageKey, storageKey]; } })(); } /** * Returns whether the key set has a key or not. * @param key * @param asOf * @returns true if the key set has the key, false if not. */ async has(key, asOf) { const result = await this.database.store.getEntryByKey(this.address, key, asOf); if (result !== undefined && result.deletion) { return false; } return result !== undefined; } async reset(toTime, recurse, meta) { let bundler = await this.database.startBundle(meta); if (!toTime) { // If no time is specified, we are resetting to epoch, which is just a clear this.clear(false, { bundler }); } else { const union = new Set(); const entriesThen = await this.database.store.getKeyedEntries(this.address, toTime); const entriesNow = await this.database.store.getKeyedEntries(this.address); for (const [key, entry] of entriesThen) { const storageKey = entry.storageKey; union.add(storageKey); } for (const [key, entry] of entriesNow) { const storageKey = entry.storageKey; union.add(storageKey); } for (const key of union) { const genericKey = (0, utils_1.fromStorageKey)(key); const thenEntry = await this.database.store.getEntryByKey(this.address, genericKey, toTime); const nowEntry = await this.database.store.getEntryByKey(this.address, genericKey); (0, utils_1.ensure)(nowEntry || thenEntry, "both then and now undefined?"); if (!nowEntry) { // This key was present then, but not now, so we need to add it back (0, utils_1.ensure)(thenEntry, "missing then entry?"); await this.addEntry(genericKey, thenEntry.value, { bundler, }); } else if (!thenEntry) { // This key is present now, but not then, so we need to delete it (0, utils_1.ensure)(nowEntry, "missing now entry?"); await this.addEntry(genericKey, Container_1.Container.DELETION, { bundler, }); } else if (nowEntry.deletion !== thenEntry.deletion) { if (nowEntry.deletion) { // Present then, deleted now. Need to revive. await this.addEntry(genericKey, Container_1.Container.INCLUSION, { bundler, }); } else if (thenEntry.deletion) { // Present now, deleted then. Need to delete. await this.addEntry(genericKey, Container_1.Container.DELETION, { bundler, }); } } else { (0, utils_1.ensure)(nowEntry.deletion === thenEntry.deletion, "last case should be same entry"); } } } if (!meta?.bundler) { await bundler.commit(); } } /** * Returns the contents of the key set as a set. * @param asOf * @returns a promise that resolves to a set with KeyTypes. */ async toSet(asOf) { const entries = await this.database.store.getKeyedEntries(this.address, asOf); const resultSet = new Set(); for (const [key, entry] of entries) { const storageKey = entry.storageKey; resultSet.add(storageKey); } return resultSet; } /** * How many entries are in the key set. * @param asOf * @returns a promise that resolves to a number. */ async size(asOf) { const entries = await this.database.store.getKeyedEntries(this.address, asOf); return entries.size; } /** * Generates a JSON representation of the data in the key set. * Mostly intended for demo/debug purposes. * @param indent true to pretty print * @param asOf effective time * @param seen (internal use only! This prevents cycles from breaking things) * @returns a JSON string */ async toJson(indent = false, asOf, seen) { //TODO(https://github.com/google/gink/issues/62): add indentation (0, utils_1.ensure)(indent === false, "indent not implemented"); if (seen === undefined) seen = new Set(); const mySig = (0, utils_1.muidToString)(this.address); if (seen.has(mySig)) return "null"; seen.add(mySig); const asSet = await this.toSet(asOf); let returning = "["; let first = true; for (const key of asSet) { if (first) { first = false; } else { returning += ","; } // returning += `"${key}"`; returning += await (0, factories_1.toJson)(key, indent === false ? false : +indent + 1, asOf, seen); } returning += "]"; return returning; } } exports.KeySet = KeySet; //# sourceMappingURL=KeySet.js.map