/v3/merchant/media/upload

1739176831

b80ffce5ceb34c7db5572c67b457e86a

mchid=1640974317

{"filename":"a.jpg","sha256":"91bab4beab8c7b6144e51fa41651cc99672e44caf6911ebc89be18960ff2fef0"}

上传结果: {"code":"SIGN_ERROR","message":"签名源串格式错误"}