Reading files with Node
How to read files using Node and the `fs` module
The simplest way to read a file in Node is to use the fs.readFile()
method, passing it the file path and a callback function that will be called with the file data (and the error):
const fs = require('fs')
fs.readFile('/Users/flavio/test.txt', (err, data) => {
if (err) {
console.error(err)
return
}
console.log(data)
})
Alternatively, you can use the synchronous version fs.readFileSync()
:
const fs = require('fs')
try {
const data = fs.readFileSync('/Users/flavio/test.txt', 'utf8')
console.log(data)
} catch (err) {
console.error(err)
}
The default encoding is utf8, but you can specify a custom encoding using a a second parameter.
Both fs.readFile()
and fs.readFileSync()
read the full content of the file in memory before returning the data.
This means that big files are going to have a major impact on your memory consumption and speed of execution of the program.
In this case, a better option is to read the file content using streams.
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