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https://github.com/jbranchaud/til
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31 lines
1.0 KiB
Markdown
31 lines
1.0 KiB
Markdown
# Check If File Exists Before Reading It
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Let's say we are working on a script that tries to read in existing data from a
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JSON data file. It is possible that data file hasn't been created and populated
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yet. In order to account for that scenario, we need to check if the file
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exists. If we try to read from a non-existant file, an error will be thrown.
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To prevent the script from error'ing out, we can use
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[`fs.existsSync`](https://nodejs.org/api/fs.html#fsexistssyncpath) to check if
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the given file path is an existing file. If we learn that the file does exist,
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we can proceed with reading it. If not, we can skip the file read and react
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accordingly.
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```javascript
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import fs from 'fs'
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const nonExistantFile = 'non-existant.json'
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// set default in case file does not exists
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let json = {}
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if(fs.existsSync(nonExistantFile)) {
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const fileData = fs.readFileSync(nonExistantFile)
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json = JSON.parse(fileData.toString())
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}
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console.log('JSON: ', json)
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```
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[source](https://flaviocopes.com/how-to-check-if-file-exists-node/)
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