I know it's kinda besides the point and I don't know what language this was being done in, but I don't personally know any language where String signature

I know it's kinda besides the point and I don't know what language this was being done in, but I don't personally know any language where String signature = "POST" + "\n" + "/api/v1/..." and String signature = "POST\n/api/v1/..." don't result in identical variables, so I'm a bit puzzled why that would result in an error. However, there's a quoting error in the failing example where the double quotes in the JSON body aren't properly escaped: String signature = "POST" + "\n" + "/api/v1/query" + "\n" + token + "\n" + timestamp + "\n" + "{"body":"content"}" It may just be the example that's not correctly formatted, but the other (working) example does in fact escape the double quotes in the JSON. I guess, depending on how forgiving the used language is with quoting, that could also be the source of the error?