"use strict";
/**
* Should be the class that programs interact with.
*
* It should take care of syncing data between storage and search.
*/
class Collection
{
/**
* @param {object} options; see public fields for details
*/
constructor(options)
{
/**
* where data is stored
* @type {Storage}
*/
this.storage = options.storage;
/**
* instance of Search
* @type {Search}
*/
this.search = options.search;
/**
* name of collection
* @type {?string}
*/
this.collectionName = options.collectionName || options.storage.collectionName || 'unspecified'; // optional
/**
* id field of records
* @type {string}
*/
this.primaryKey = options.primaryKey || 'id';
/**
* search definition
* @type {SearchMeta}
*/
this.searchMeta = options.searchMeta || {};
}
/**
* Call this to connect to storage units and search
*/
async initialise()
{
await this.storage.connect();
const records = await this.storage.readAllRecords();
await this.search.initialise(this.searchMeta, records);
return records;
}
/**
* Helper creation method
*/
static create(storage, search, Class)
{
return new Promise((resolve, reject) =>
{
let pimaryKey = Class.pimaryKey;
let searchMeta = Class.searchMeta;
let collection = new Class({
storage,
search,
pimaryKey,
searchMeta
});
collection.initialise()
.then(() => resolve(collection), reject);
});
}
/**
* Add a new record to collection.
*/
async createRecord(record)
{
record = await this.storage.createRecord(record);
console.log('CREATED', this.collectionName, record[this.primaryKey]);
await this.search.createRecord(record);
return record;
}
/**
* Read an existing record.
*/
readRecord(record)
{
return this.storage.readRecord(record);
}
/**
* Update an existing record.
*/
async updateRecord(record)
{
record = await this.storage.updateRecord(record);
console.log('UPDATED', this.collectionName, record[this.primaryKey]);
await this.search.updateRecord(record);
return record;
}
/**
* Update field of a record.
*
* Override this to inject custom processing rules.
*/
updateField(record, field, value)
{
record[field] = value;
}
/**
* Delete a record from collection
*/
async deleteRecord(record)
{
record = await this.storage.deleteRecord(record);
console.log('DELETED', this.collectionName, record[this.primaryKey]);
await this.search.deleteRecord(record);
return record
}
/**
* Search for records in collection using query.
*/
async searchRecords(query)
{
let offset = query.offset;
delete query.offset;
let limit = query.limit;
delete query.limit;
let records = await this.search.searchRecords(query);
let results = {
results: records,
total: records.length,
offset: offset,
};
Eif (query.sort)
{
results.sort = query.sort;
results.order = query.order;
}
records = records.splice(offset, limit);
records = records.map(id =>
{
const query = {};
query[this.primaryKey] = id;
return this.readRecord(query);
});
records = await Promise.all(records);
return {
results: records.map(x => this.stripRecord(x, query.extra))
};
}
/**
* Strips a record to return as search result.
*/
stripRecord(record, extra = [])
{
let out = {};
out[this.primaryKey] = record[this.primaryKey];
for (let field in this.searchMeta.fields)
{
let value = record[field];
if (value !== undefined)
{
out[field] = value;
}
}
for (let field of extra)
{
let value = record[field];
if (value !== undefined)
{
out[field] = value;
}
}
return out;
}
}
module.exports = Collection;
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