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The validate command checks if an ID is valid and optionally identifies its type. It supports single ID validation, batch processing from stdin, and multiple output formats.

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Basic Usage

Validate a single ID with automatic type detection: 
uniku validate 018e5e5c-7c8a-7000-8000-000000000000
# => Valid UUID

uniku validate 01HW9T2W9W9YJ3JZ1H4P4M2T8Q
# => Valid ULID

uniku validate invalid-id
# => Invalid ID
# (exits with code 2)
The CLI automatically detects the ID type and validates against the appropriate format.

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Explicit Type Validation

Specify the expected ID type using --type: 
# Validate as UUID
uniku validate --type uuid 550e8400-e29b-41d4-a716-446655440000
# => Valid UUID

# Validate as ULID
uniku validate --type ulid 01HW9T2W9W9YJ3JZ1H4P4M2T8Q
# => Valid ULID

# Type mismatch
uniku validate --type uuid 01HW9T2W9W9YJ3JZ1H4P4M2T8Q
# => Invalid UUID
​
--type
uuid | ulid | nanoid | cuid | ksuid
Expected ID type. If omitted, type is auto-detected.
uniku validate --type ulid 01HW9T2W9W9YJ3JZ1H4P4M2T8Q
Auto-detection works by testing the ID format against all known patterns. Explicit type checking is faster and more precise.

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Batch Validation

Validate multiple IDs from stdin using --stdin: 
# From a file
cat ids.txt | uniku validate --stdin

# From echo
echo -e "018e5e5c-7c8a-7000-8000-000000000000\n01HW9T2W9W9YJ3JZ1H4P4M2T8Q" | uniku validate --stdin

# From command output
uniku uuid --count 5 | uniku validate --stdin
​
--stdin
boolean
default:"false"
Read IDs from stdin, one per line
cat ids.txt | uniku validate --stdin

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Example: Batch Validation

Create a file with multiple IDs: 
cat > ids.txt <<EOF
018e5e5c-7c8a-7000-8000-000000000000
01HW9T2W9W9YJ3JZ1H4P4M2T8Q
V1StGXR8_Z5jdHi6B-myT
invalid-id
EOF

# Validate all IDs
cat ids.txt | uniku validate --stdin
Output: 
018e5e5c-7c8a-7000-8000-000000000000: Valid UUID
01HW9T2W9W9YJ3JZ1H4P4M2T8Q: Valid ULID
V1StGXR8_Z5jdHi6B-myT: Valid Nanoid
invalid-id: Invalid ID
The command exits with code 2 if any ID is invalid.
When using --stdin, the command fails if any ID is invalid. Use --json or --quiet for programmatic error handling.

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Quiet Mode

Use --quiet for silent validation with exit codes only: 
# Valid ID (exits with 0)
uniku validate --quiet 018e5e5c-7c8a-7000-8000-000000000000
echo $?  # => 0

# Invalid ID (exits with 2)
uniku validate --quiet invalid-id
echo $?  # => 2
​
--quiet
boolean
default:"false"
No output, exit code only
  • 0 — ID is valid
  • 2 — ID is invalid
uniku validate --quiet 01HW9T2W9W9YJ3JZ1H4P4M2T8Q
This is useful in shell scripts: 
if uniku validate --quiet "$ID"; then
  echo "Valid ID"
else
  echo "Invalid ID"
  exit 1
fi

​
JSON Output

Get structured validation results with --json: 
uniku validate --json 018e5e5c-7c8a-7000-8000-000000000000

{
  "id": "018e5e5c-7c8a-7000-8000-000000000000",
  "valid": true,
  "type": "uuid"
}
For invalid IDs: 
uniku validate --json invalid-id

{
  "id": "invalid-id",
  "valid": false,
  "type": null
}
​
--json
boolean
default:"false"
Output validation results as JSON
uniku validate --json 01HW9T2W9W9YJ3JZ1H4P4M2T8Q

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Batch JSON Output

Combine --stdin and --json for structured batch results: 
echo -e "018e5e5c-7c8a-7000-8000-000000000000\ninvalid-id" | uniku validate --stdin --json

[
  {
    "id": "018e5e5c-7c8a-7000-8000-000000000000",
    "valid": true,
    "type": "uuid"
  },
  {
    "id": "invalid-id",
    "valid": false,
    "type": null
  }
]
Parse with jq: 
# Count valid IDs
cat ids.txt | uniku validate --stdin --json | jq '[.[] | select(.valid)] | length'

# Extract invalid IDs
cat ids.txt | uniku validate --stdin --json | jq -r '.[] | select(.valid == false) | .id'

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Exit Codes

The validate command uses these exit codes:
CodeMeaning
0All IDs are valid
1Command error (missing input, invalid arguments)
2One or more IDs are invalid
Example usage: 
if uniku validate "$ID"; then
  echo "Proceeding with valid ID"
else
  CODE=$?
  if [ $CODE -eq 2 ]; then
    echo "Invalid ID format"
  else
    echo "Validation error"
  fi
  exit $CODE
fi

​
Examples

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Pipeline Validation

Validate IDs generated in a pipeline: 
# Generate and validate
uniku uuid --version 7 --count 10 | uniku validate --stdin

# Generate, validate, and inspect
uniku ulid --count 5 | tee ids.txt | uniku validate --stdin

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Filter Valid IDs

Use jq to filter valid IDs from batch validation: 
cat ids.txt | uniku validate --stdin --json | jq -r '.[] | select(.valid) | .id'

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Validation in CI/CD

Validate IDs in a CI pipeline: 
#!/bin/bash
set -e

# Validate required ID
if ! uniku validate --quiet --type uuid "$UUID"; then
  echo "Error: Invalid UUID in environment variable"
  exit 1
fi

echo "UUID validation passed"

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Type Detection Report

Generate a report of ID types: 
cat mixed_ids.txt | uniku validate --stdin --json | jq -r '.[] | "\(.id): \(.type // "unknown")"'

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Supported ID Types

The validator supports these ID formats:
TypeFormatExample
UUID8-4-4-4-12 hex with hyphens550e8400-e29b-41d4-a716-446655440000
ULID26 characters, Crockford base3201HW9T2W9W9YJ3JZ1H4P4M2T8Q
NanoidConfigurable length, URL-safeV1StGXR8_Z5jdHi6B-myT
CUID22-32 characters, starts with letterclhw9t2w9w9yj3jz1h4p4m2t
KSUID27 characters, base622HbcvN9VFGzP8jR5mK3QxW4d
Auto-detection is pattern-based. For ambiguous formats (like Nanoid), use --type to ensure correct validation.

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Next Steps

Generate IDs

Generate IDs to validate

Inspect IDs

Extract metadata from valid IDs

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