2 * Copyright (C) 2018-2022 Nick Downing <nick@ndcode.org>
3 * SPDX-License-Identifier: MIT
5 * Permission is hereby granted, free of charge, to any person obtaining a copy
6 * of this software and associated documentation files (the "Software"), to
7 * deal in the Software without restriction, including without limitation the
8 * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
9 * sell copies of the Software, and to permit persons to whom the Software is
10 * furnished to do so, subject to the following conditions:
12 * The above copyright notice and this permission notice shall be included in
13 * all copies or substantial portions of the Software.
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
18 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
20 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
24 import assert from 'assert'
29 this.diag = diag || false
32 async ref(key, factory_func, destroy_func) {
33 let result = this.map.get(key)
34 if (result === undefined) {
37 value: factory_func(), // don't await it here
38 destroy_func: destroy_func
40 this.map.set(key, result)
44 console.log(`ref ${key} refs -> ${result.refs}`)
47 value = await result.value
51 console.log(`err ${key} refs-> ${result.refs}`)
52 if (result.refs === 0)
60 let result = this.map.get(key)
61 assert(result !== undefined && result.refs > 0)
64 console.log(`unref ${key} refs -> ${result.refs}`)
65 if (result.refs === 0) {
67 if (result.destroy_func !== undefined)
69 await result.destroy_func(await result.value)
72 console.error(err.stack || err.message)
78 export default Resources