Node.js 如何将缓冲区转换为 stream？

Question

Im receiving a buffer from a post request in the form-data (which is being handled by multer). And i need to pass that along to another service by making post request using form-data.

const documentFile = req.body.image;
const image = bufferToStream(documentFile.buffer);

function bufferToStream(binary) {
    const readableInstanceStream = new Readable({
      read() {
        this.push(binary);
        this.push(null);
      },
    });

    return readableInstanceStream;

  }

image is now a Readable rather than a ReadStream you would get from fs.createReadStream(). I need a readstream.

So i can use axios to send a form-data request like this.

const formData = new FormData();

formData.append("image",image);

const options: any = {
            url,
            method: "post",
            headers: formData.getHeaders(),
            data: formData,
            config: retryConfig,
};
await axios(options)

Answer 1

After getting file from multer , you can do exactly the same on server as if you were sending from client. Install form-data package and try below snippet.

const FormData = require('form-data');

...
const formData = new FormData();
formData.append("image", req.body.image);
axios({ data: formData });