Hashlib

The runtime exposes a deterministic hashlib module with explicit text and hex helpers:

hashlib.sha256_text(value)
hashlib.sha256_hex(value)
hashlib.sha3_text(value)
hashlib.sha3_hex(value)

Input Rules

All helpers accept a string.

Use the _text helpers when the value is an ordinary contract message, identifier, JSON string, canonical payload, permit message, or other human-readable value. The runtime hashes the exact UTF-8 bytes of the string.

Use the _hex helpers only when the value is already encoded as raw bytes in hex form. Hex input must be unprefixed, have an even number of characters, and must not contain whitespace.

payload_hash = hashlib.sha3_text("transfer:alice:bob:10")
byte_hash = hashlib.sha3_hex("68656c6c6f")

hashlib.sha3_text("68656c6c6f") hashes those ten text characters. hashlib.sha3_hex("68656c6c6f") decodes the hex first and hashes hello.

Output

All functions return lowercase hex strings.

Common Uses

• deterministic identifiers
• permit or authorization-message hashing
• compact code or config fingerprints
• note, payload, or commitment helper flows in privacy-oriented contracts

Design Guidance

• choose _text or _hex at the call site; do not normalize untrusted input by guessing
• keep the message format stable before hashing
• include fixed separators, field names, or lengths when hashing multiple fields
• use _hex only for validated byte payloads, not for user-facing identifiers