Verify at the command line

You have a pack and you want to check it yourself. You need Node and nothing else. You do not need a Sanning account, an API key, or any cooperation from the party who gave you the pack.

The two steps

A pack is a zip. The kernel reads the bundle inside it, so extract first.

unzip pack.zip -d pack
cd pack
npx @sanning/proof verify bundle.json --logs logs/

A verified pack prints its per-record results and exits 0:

VERIFIED  verified offline (no gateway re-fetch requested)
  logs: 37/37 disclosed verified

Exit codes

Code	Means
0	Verified
1	A check ran and failed. The output names the record
2	The input could not be read at all

Two errors you might hit first

Both exit 2, before any check runs. You pointed it at the zip. The kernel reads JSON, not an archive:

pack.zip is not valid JSON: Unexpected token 'P', "PK  "... is not valid JSON

Extract the zip and point at bundle.json inside it. You pointed it at the directory.

cannot read pack/: EISDIR: illegal operation on a directory, read

Name the file, not the folder that holds it.

Check the tamper-evidence yourself

Do not take the verdict on trust. Break the pack and watch it fail.

# Change one byte of any disclosed log
printf 'x' | dd of=logs/SOME_EVENT_ID.json bs=1 seek=200 conv=notrunc

npx @sanning/proof verify bundle.json --logs logs/

It exits 1 and names the record you touched. Replace SOME_EVENT_ID with any filename from logs/.

Confirm the file actually changed, with sha256sum before and after. An edit that writes the same byte back produces an identical file, which verifies clean and looks exactly like a passing tamper test.

Confirm the witness on the public record

The verdict above is offline. It names a witness without contacting it. To check that the witness holds those bytes, pass a gateway:

npx @sanning/proof verify bundle.json --logs logs/ https://arweave.net

That turns a claim you read into one you checked. See What a verdict means for why the two are different.

Python

sanning-proof on PyPI is the same kernel and ships no command line. Use it as a library:

import json, pathlib
from sanning_proof.evidence import verify_evidence_bundle

bundle = json.load(open("bundle.json"))
content = {p.stem: p.read_bytes() for p in pathlib.Path("logs").glob("*.json")}

result = verify_evidence_bundle(bundle, content=content)
print(result.status)

Two kernels, one corpus. They agree record by record, and disagreeing is a bug we treat as release-blocking.

Getting started

Concepts

Guides

Verify

Reference

Verify at the command line

The two steps

Exit codes

Two errors you might hit first

Check the tamper-evidence yourself

Confirm the witness on the public record

Python

​The two steps

​Exit codes

​Two errors you might hit first

​Check the tamper-evidence yourself

​Confirm the witness on the public record

​Python

The two steps

Exit codes

Two errors you might hit first

Check the tamper-evidence yourself

Confirm the witness on the public record

Python