NAME

jsonvalidate - Validate JSON instances against a JSON Schema (Draft 2020-12)

SYNOPSIS

jsonvalidate --schema schema.json --instance data.json
jsonvalidate -s schema.json -i instances.array.json
jsonvalidate -s schema.json -i - < data.jsonl --jsonl --json
jsonvalidate -s root.json -s subdefs.json -i items.ndjson --jsonl --compile --register-formats

DESCRIPTION

A lean CLI powered by JSON::Schema::Validate. It supports arrays of instances, JSON Lines, local file $ref, optional HTTP(S) fetch for $ref (when LWP::UserAgent is available), and useful output modes.

OPTIONS

Selection

• --schema, -s FILE1, FILE2, FILE3, etc...

  Root schema; additional --schema files are made available to the resolver, such as when their `'$id'` is referenced.

• --instance, -i FILE1, FILE2, FILE3, etc...

  Instances to validate. Use - for STDIN. An instance may be a single object, a single array (each element validated), or JSON Lines with --jsonl.

  Not that you can either use - (STDIN), or one or more files, but you cannot mix both.

• --jsonl

  Treat each line as an instance (NDJSON).

Output

• --quiet, -q

  Suppress per-record output; still returns non-zero exit on failures.

• --errors-only

  Only print failed records (ignored when --json is used).

• --json

  Emit JSON objects (one per instance) with { index, ok, errors[] }.

Behavior

• --allow-file-refs

  Enabled by default.

  When enabled, perform resolution of relative or file:// references.

• --allow-http

  Disabled by default.

  This is an alias for --remote-refs

• --compile / --no-compile

  Enable compiled fast-path for repeated validation.

• --content-checks

  Enable contentEncoding, contentMediaType, contentSchema. Registers a basic application/json validator/decoder.

• --extensions

  Enables non-standard extensions. Right now this includes uniqueKeys

• --ignore-unknown-required-vocab

  Ignore unknown vocabularies listed in schema `'$vocabulary'` required.

• --register-formats

  Register built-in format validators (date, email, hostname, ip, uri, uuid, JSON Pointer, regex, etc.).

• --max-errors N

  Maximum recorded errors per validation (default 200).

• --normalize / --no-normalize

  Round-trip instances through JSON to enforce strict JSON typing (default on).

• --remote-refs

  Allow fetching of http:// and https:// $ref URIs.

  By default this is OFF — fictional $id values like "https://schemas.example.com/..." will NOT be fetched.

  This is the modern, safe default (prevents SSRF, accidental traffic).

• --schema-base DIR

  A base directory to resolve relative file $ref (defaults to the directory of the first --schema).

• --trace

  Record lightweight trace; cap with --trace-limit; sample with --trace-sample.

• --trace-limit N

  Max number of trace entries per validation (0 = unlimited).

• --trace-sample P

  Sampling percentage for trace events.

• --unique-keys / --no-unique-keys

  Enables the non-standard extension uniqueKeys

EXIT CODES

• 0

  All instances validated.

• 1

  At least one instance failed.

• 2

  Usage error.

SEE ALSO

JSON::Schema::Validate, JSON

AUTHOR

Jacques Deguest <jack@deguest.jp>

COPYRIGHT

Copyright(c) 2025 DEGUEST Pte. Ltd.

All rights reserved

This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.