Encryption: Hash Functions in JSONata ($md5 and $sha256)

JSONata provides cryptographic hash functions that allow values to be transformed into unique and deterministic representations.

These functions can be used to:

• Ensure data integrity

• Create unique identifiers

• Anonymize sensitive values

• Ensure compatibility with external systems

Supported functions:

• $md5(value)

• $sha256(value, digestFormat?)

Difference Between MD5 and SHA-256

Algorithm	Hash Size	Security	Common Usage
MD5	32 characters (128 bits)	Weak, collision-prone	Checksums, simple validation
SHA-256	64 characters (256 bits)	Strong, recommended	Authentication, blockchain, cryptography

Function $md5(value)

• Calculates the MD5 hash of the provided value.

• Return: fixed 32-character hexadecimal string

• Digest parameter: not supported

Example

Input:
{ "status": "200" }

Expression:
$md5(status)

Output:
{ "data": "3644a684f98ea8fe223c713b77189a77" }

Function $sha256(value, digestFormat?)

• Calculates the SHA-256 hash of the provided value.

• Return: fixed 64-character hexadecimal string (by default)

• Digest parameter: supports digestFormat to change the output format

Supported formats (digestFormat)

Value	Description	Example Output
"hex" (default)	Hexadecimal representation	27badc983df1780b60c2...
"base64"	Standard Base64	J7cmD3xeAtgwrP6nToZoA...
"base64url"	Base64 adapted for URLs/JWTs	J7cmD3xeAtgwrP6nToZoA...

Practical Examples

SHA-256 in hex (default)

Input:
{ "status": "200" }

Expression:
$sha256(status)


Output:
{ "data": "27badc983df1780b60c2b3fa9d3a19a00e46aac798451f0febdca52920faaddf" }

SHA-256 in Base64

Input:
{ "status": "200" }

Expression:
$sha256(status,"base64")

Output:
{ "data": "J7cmD3xeAtgwrP6nToZoA5GqseYRR8P69y1KSD6rd8=" }

SHA-256 in complex JSON (hex)

Input:
{ "response": "{...JSON object...}" }

Expression:
$sha256(response)

Output:
{ "data": "885826bd782b9b92cca593385729cc17ea05ca3f8f68935c5a1613102dfc066" }

SHA-256 in complex JSON (Base64)

Input:
{ "response": "{...JSON object...}" }

Expression:
$sha256(response,"base64")

Output:
{ "data": "CFAmvXgrCbksyIkZhXApzBfqBco/j2A5XFoWExAt/AY=" }

Resumo dos tipos de digest

Digest Format	Description
hex	Hexadecimal representation (default)
base64	Standard Base64 representation
base64url	Base64 adapted for URLs/JWTs
latin1	Each byte converted into a Latin-1 character
utf8	Return handled as a UTF-8 string
binary/buffer	Return as raw binary data (when supported)