hash

calculates a digest hash

(any subject, string algorithm, string resultFormat) -> any

Calculates a digest hash of given subject using a specified hashing algorithm.

Processing

The digest of subject is calculated as follows:

• If subject is nil, nil is returned.

• If subject is of type binary the digest of its bytes is returned.

• If subject is of type string the digest of the UTF-8 bytes of the string is returned.

• If subject is of a type that can be cast to string - such as numeric, boolean or datetime types - it is cast to string and the digest of the UTF-8 bytes of the string is returned.

• If subject is a list, the bytes to hash are constructed as follows:
  Each element contributes a byte sequence consisting of

  1. bytes of the element index as UTF-8 string
  2. bytes of the element value - a nil value contributes no bytes

  The byte sequences of all elements are concatenated and hashed.

  For example:
  The empty list has the same hash value as the empty string.
  The value ["zero", nil, "two"] has the same hash value as the string '0zero12two'

• If subject is a dict, the bytes to hash are constructed as follows:
  Each element contributes a byte sequence consisting of

  1. bytes of element key as UTF-8 string
  2. bytes of the element value - a nil value contributes no bytes

  The byte sequences of all elements are concatenated in lexographical order of keys and hashed.

  For example:
  The empty dict has the same hash value as the empty string.
  The value {:a 'one', :b nil, :c 'three'} has the same hash value as the string 'aonebcthree'.

• If subject is or contains a data type that is not convertible to bytes via the above rules, an error is thrown.

Parameters

Name	Type	Description
subject	any	the value to hash
algorithm	string	The following algorithms are supported: MD2 MD5 SHA-1 SHA-224 SHA-256 SHA-384 SHA-512 SHA-512/224 SHA-512/256 SHA3-224 SHA3-256 SHA3-384 SHA3-512
resultFormat	string	The hashing function can return the hash digest in the following forms: binary - the returned value is of type binary and contains the bytes of the digest hex string - the returned value is of type string and contains a hexadecimal representation of the bytes of the digest - all letters are lowercase