Calculate the content-digest of an HTTP request.
For all requests that contain a body, the content digest of the body must be calculated and added as a request header named content-digest, as described in the IETF draft for HTTP digest fields.
In summary, the digest calculation algorithm as used for the Investment API can be applied as follows:
- Capture the entire request body's byte stream.
- Calculate the SHA-512 hash of the body content.
- Encode the resulting value using Base64 encoding
- Add a request header named
content-digestwith this value:sha-512=:{digest value}:, where{digest value}is replaced by the result of the previous step.
From the above description you should now understand how to calculate a digest. Here are some examples you can use to check your understanding.
| Request body | Content length | content-digest header value |
|---|---|---|
| hello | 18 | sha-512=:WZDPaVn/7XgHaAy8pmojAkGWoRx2UFChF41A2svX+TaPm+AbwAgBWnrIiYllu7BNNyealdVLvRwEmTHWXvJwew==: |
| key | 16 | sha-512=:Hd9/AvGZkbjitW1+Ml8Fg1ux1mtcDYe6mLQjDyoowIWa3LM/PmwN2v9O+MjtQGrCA3EQWUL54dlgxKHyYbrucw==: |
| 0 | No content-digest header should be included in the request. |