Authentication

caution

The authentication has already been encapsulated by Webull SDK, and no additional processing is required. Here is just a description of the signature generation process.

Catalog

1> Signature generation instructions
2> The content of the signature
3> Signature construction example
4> URL encoding considerations
5> Other instructions

Signature Generation Instructions

The signature value sig is the signature value generated by the request source param and secret according to a certain signature method, which is used to improve the tamper-proof modification of the parameters of the transmission process.
There are three steps in the generation of the signature value: construct the source param, construct the secret, and generate the signature value.

The Content of the Signature

The signature source param mainly consists of 4 parts:

1> Http Request Uri 
2> QueryParams in Http URLs
3> Http Request Body
4> Http Request Headers
// Note: The http post method is currently not supported to pass k=v format parameters in the body, currently only application/json is supported

The signature-related header conventions are as follows:

Name	Description
x-app-key	Access secret id
x-signature	Signature value
x-signature-algorithm	Signature algorithm, default HMAC-SHA1
x-signature-version	Signature algorithm version, default 1.0
x-signature-nonce	Signature Unique Random Number
x-timestamp	Requested timestamp, ISO8601 time format, UTC time zone
host	http request default: host:port, example: api.webull.com:8080

The signature rules are as follows:

1> Content involved in signature calculation
1.1> http request uri 
1.2> http request query params (Note: param is the original data without urlencode)
1.3> http request body 
1.4> http request headers, including: x-app-key、x-signature-algorithm、x-signature-version、x-signature-nonce、x-timestamp、host
2> How signature content is organized: 
2.1> The query params and headers are organized into a map structure according to k, v, and then sorted according to the value of the k string from small to large, and then connected in the way of k1=v1&k2=v2, and finally get s1
2.2> Perform md5 processing on the http request body, method: upcase(md5(body)), get: s2 (Note: body is empty and does not participate in the signature)
2.3> Concatenate: uri + "&" + s1 + "&" + s2, resulting in: s3  
     Note: when body is empty, s3 = uri + '&' + s1  
3> Generate signature: signature = base64(HMAC-SHA1(app_secret + "&", encoded_sign_string))

Signature Construction Example

Request Content

uri: /trade/place_order

QueryParams:

Name	Example Value	Remark
a1	webull	Value is not urlencoded
a2	123	Value is not urlencoded
a3	xxx	Value is not urlencoded
q1	yyy	Value is not urlencoded

Headers:

Name	Example Value	Remark
x-app-key	776da210ab4a452795d74e726ebd74b6
x-timestamp	2022-01-04T03:55:31Z
x-signature-version	1.0
x-signature-algorithm	HMAC-SHA1
x-signature-nonce	48ef5afed43d4d91ae514aaeafbc29ba
host	api.webull.com

Body: {"k1":123,"k2":"this is the api request body","k3":true,"k4":{"foo":[1,2]}}

Secret: 0f50a2e853334a9aae1a783bee120c1f

Step1: Construct the Source Param

Sort the dictionary from small to large according to the key, and get the following order data:
Key: a1 , Value: webull
Key: a2 , Value: 123
Key: a3 , Value: xxx
Key: host , Value: api.webull.com
Key: q1 , Value: yyy
Key: x-app-key , Value: 776da210ab4a452795d74e726ebd74b6
Key: x-signature-algorithm , Value: HMAC-SHA1
Key: x-signature-nonce , Value: 48ef5afed43d4d91ae514aaeafbc29ba
Key: x-signature-version , Value: 1.0
Key: x-timestamp , Value: 2022-01-04T03:55:31Z

OriginBody: {"k1":123,"k2":"this is the api request body","k3":true,"k4":{"foo":[1,2]}}
Body MD5: ToUpper(MD5(body)) = E296C96787E1A309691CEF3692F5EEDD
Note: The json string generated by some json tools contains spaces between the key and value, which will cause the validation to fail

The concatenated source param is as follows:
/trade/place_order&a1=webull&a2=123&a3=xxx&host=api.webull.com&q1=yyy&x-app-key=776da210ab4a452795d74e726ebd74b6&x-signature-algorithm=HMAC-SHA1&x-signature-nonce=48ef5afed43d4d91ae514aaeafbc29ba&x-signature-version=1.0&x-timestamp=2022-01-04T03:55:31Z&E296C96787E1A309691CEF3692F5EEDD

Get encoded_sign_string after encodeURIComponent:
%2Ftrade%2Fplace_order%26a1%3Dwebull%26a2%3D123%26a3%3Dxxx%26host%3Dapi.webull.com%26q1%3Dyyy%26x-app-key%3D776da210ab4a452795d74e726ebd74b6%26x-signature-algorithm%3DHMAC-SHA1%26x-signature-nonce%3D48ef5afed43d4d91ae514aaeafbc29ba%26x-signature-version%3D1.0%26x-timestamp%3D2022-01-04T03%3A55%3A31Z%26E296C96787E1A309691CEF3692F5EEDD

Step2: Add Key Secret

The way to get the secret: Add a byte of "&" at the end of the app_secret of the application, that is, app_secret&, for example:

0f50a2e853334a9aae1a783bee120c1f&

Step3: Generate Signed Value

How to generate:: 
signature = base64(HMAC-SHA1(app_secret + "&", encoded_sign_string))

1> Use HMAC-SHA1 encryption algorithm, use the key obtained in Step2 to encrypt the source param obtained in Step1
2> Then base64 encode the encrypted string
3> The result of the obtained signature value is as follows: kvlS6opdZDhEBo5jq40nHYXaLvM=

URL Encoding Considerations

During signature verification, all non-alphanumeric characters in the string except "-", "_", "." are required to be replaced with percent sign (%) followed by two hexadecimal digits, hexadecimal Letters in system numbers must be uppercase.

Other Instructions

1> In some special cases, such as when there are multiple keys in the Query parameter, the values need to be sorted in ascending order by value, and then connected with '&'. For example:
     url?k1=v1&k1=v2&k1=v3
     After the connection is processed: k1 = v1&v2&v3 , otherwise, the signature will not pass
2> Golang json.Marshal defaults escapeHtml being true, which will escape <, >, &. In this case, the escaped content needs to be processed and replaced with the original characters. The general processing is as follows:
    func trans(data []byte) []byte {
        data = bytes.Replace(data, []byte("\\u0026"), []byte("&"), -1)
        data = bytes.Replace(data, []byte("\\u003c"), []byte("<"), -1)
        data = bytes.Replace(data, []byte("\\u003e"), []byte(">"), -1)
        return data
    }