TypeError: headers[key].trim is not a function

Question

I'm trying to execute an API on AWS, that requires a CORS headers, i make the request with all the information but i receive the next error:

"TypeError: headers[key].trim is not a function"

If i not send de CORS, i receive the error:

from origin 'http://localhost:3000' has been blocked by CORS policy: No 'Access-Control-Allow-Origin' header is present on the requested resource.

My code:

async function Request(){
    let arra = "test"
    const data2 = {
        "parm1" : "one", "parm2" : "two"
    };
    const headers = {
        "Access-Control-Allow-Origin": "*",
        "Access-Control-Allow-Credentials": true
    };
    try{
        const resp = await API.post("Lambda", "/admin/digital/app/uploadtodynamo", {
            body: data2, headers: headers
        });
        console.log("error 1")
        console.log(resp)
    }
    catch(error)
    {
        console.log("error 2")
        console.log(error)
    }
}

React version: "^16.12.0"

Amplify: "^2.2.5"

Answer 1

I encountered this error due to providing incorrect Tagging-value to my PutObjectCommand.

It should be a key-value formatted string, i.e. "key=value;key=value". However, I accidentally supplied a boolean, false:

async function uploadFile(fileContent, fileKey, contentType, tagging) {
  try {
    await s3.send(
      new PutObjectCommand({
        Bucket: UploadBucketName,
        Key: fileKey,
        Body: fileContent,
        Tagging: tagging, // <-- ERROR
      }),
    );

    const getCommand = new GetObjectCommand({
      Bucket: UploadBucketName,
      ContentType: contentType,
      ACL: 'public-read',
      Key: fileKey,
    });

    return getSignedUrl(s3, getCommand, { expiresIn: 3600 });
  } catch (e) {
    throw new Error(`Could not upload file to S3 ${e}`);
  }
}

Protip: Use TypeScript.

Answer 2

Chiming in, I got this error when using Metadata. One of my fields was a number.

const uploaded = await sendUploadCommand(new PutObjectCommand({
    ACL: "authenticated-read",
    Bucket: myBucket,
    Body: file,
    Key: `/${folder}/${filename}.${r.ext}`,
    ContentType: r.mime,
    Metadata: {
        userId: user.id, // A string, this is fine
        flags: user.flags // ? A number, this is the error! Add '.toString()'
    }
}));

The documentation states that Metadata should be KV of strings: PutObjectRequest.Metadata?: {[p: string]: string}