Question

eRror：

Failed to compile.

Module not found: Error: Can't resolve 'buffer' in '/home/canakil/Code/cemil-mern/frontend/node_modules/safe-buffer'
BREAKING CHANGE: webpack < 5 used to include polyfills for node.js core modules by default.
This is no longer the case. Verify if you need this module and configure a polyfill for it.

If you want to include a polyfill, you need to:
        - add a fallback 'resolve.fallback: { "buffer": require.resolve("buffer/") }'
        - install 'buffer'
If you don't want to include a polyfill, you can use an empty module like this:
        resolve.fallback: { "buffer": false }
WARNING in ./node_modules/sax/lib/sax.js 139:13-37
Module not found: Error: Can't resolve 'stream' in '/home/canakil/Code/cemil-mern/frontend/node_modules/sax/lib'

BREAKING CHANGE: webpack < 5 used to include polyfills for node.js core modules by default.
This is no longer the case. Verify if you need this module and configure a polyfill for it.

If you want to include a polyfill, you need to:
        - add a fallback 'resolve.fallback: { "stream": require.resolve("stream-browserify") }'
        - install 'stream-browserify'
If you don't want to include a polyfill, you can use an empty module like this:
        resolve.fallback: { "stream": false }

WARNING in [eslint]
src/pages/Create.js
  Line 6:10:  'populateExcelForMonthly' is defined but never used  no-unused-vars

ERROR in ./node_modules/safe-buffer/index.js 3:13-30
Module not found: Error: Can't resolve 'buffer' in '/home/canakil/Code/cemil-mern/frontend/node_modules/safe-buffer'

BREAKING CHANGE: webpack < 5 used to include polyfills for node.js core modules by default.
This is no longer the case. Verify if you need this module and configure a polyfill for it.

If you want to include a polyfill, you need to:
        - add a fallback 'resolve.fallback: { "buffer": require.resolve("buffer/") }'
        - install 'buffer'
If you don't want to include a polyfill, you can use an empty module like this:
        resolve.fallback: { "buffer": false }

ERROR in ./node_modules/xlsx-populate/lib/Encryptor.js 12:15-32
Module not found: Error: Can't resolve 'crypto' in '/home/canakil/Code/cemil-mern/frontend/node_modules/xlsx-populate/lib'

BREAKING CHANGE: webpack < 5 used to include polyfills for node.js core modules by default.
This is no longer the case. Verify if you need this module and configure a polyfill for it.

If you want to include a polyfill, you need to:
        - add a fallback 'resolve.fallback: { "crypto": require.resolve("crypto-browserify") }'
        - install 'crypto-browserify'
If you don't want to include a polyfill, you can use an empty module like this:
        resolve.fallback: { "crypto": false }

ERROR in ./node_modules/xlsx-populate/lib/Workbook.js 4:11-24
Module not found: Error: Can't resolve 'fs' in '/home/canakil/Code/cemil-mern/frontend/node_modules/xlsx-populate/lib'

webpack compiled with 3 errors and 2 warnings

我会感谢我为什么遇到此错误以及含义的任何方向。

这通常发生在WebPack 4.x中。 您正在使用什么版本？ 升级到5可能会有所帮助。