41 lines
1.3 KiB
Markdown
41 lines
1.3 KiB
Markdown
# promise-all-reject-late
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Like Promise.all, but save rejections until all promises are resolved.
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This is handy when you want to do a bunch of things in parallel, and
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rollback on failure, without clobbering or conflicting with those parallel
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actions that may be in flight. For example, creating a bunch of files,
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and deleting any if they don't all succeed.
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Example:
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```js
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const lateReject = require('promise-all-reject-late')
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const { promisify } = require('util')
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const fs = require('fs')
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const writeFile = promisify(fs.writeFile)
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const createFilesOrRollback = (files) => {
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return lateReject(files.map(file => writeFile(file, 'some data')))
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.catch(er => {
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// try to clean up, then fail with the initial error
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// we know that all write attempts are finished at this point
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return lateReject(files.map(file => rimraf(file)))
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.catch(er => {
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console.error('failed to clean up, youre on your own i guess', er)
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})
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.then(() => {
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// fail with the original error
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throw er
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})
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})
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}
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```
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## API
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* `lateReject([array, of, promises])` - Resolve all the promises,
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returning a promise that rejects with the first error, or resolves with
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the array of results, but only after all promises are settled.
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