Nodejs upload pictures to the server how to solve

  node.js, question
  1. Nodejs pictures are uploaded to the server, preferably with asynchronous upload support.

  2. JavaScript is required to upload code and nodej server-side code.

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I have been online for a long time, but I have not found enough. In other words, when uploading, js did not find a reasonable way to upload, and did not know whether to upload the path to parse or upload the binary stream directly. Confused, ask for help.

Nodejs uses the formidable module, and if the front end uses the iframe plus the form to upload it.