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Use case

Regression probe for the custom Presidio PatternRecognizer registered for US_SSN. Presidio’s built-in SSN recognizer scores bare dashed format (123-45-6789) well below the default threshold, so Declaw ships a custom recognizer that fires at a lower confidence. This example uses httpbin.org/post as an echo mirror to verify that SSN patterns are caught and redacted before reaching the upstream.

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What you’ll learn

  • Configuring PIIConfig with rehydrate_response=False so the echo response shows exactly what the upstream received
  • Using httpbin.org/post as a zero-dependency mirror for redaction tests
  • Verifying that SSN, email, and person-name PII types are all redacted

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Prerequisites

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Code walkthrough

Create a security policy with PII redaction enabled and rehydration disabled. Rehydration must be off so the echoed response shows the raw redacted tokens: 
from declaw import (
    ALL_TRAFFIC,
    AuditConfig,
    NetworkPolicy,
    PIIConfig,
    Sandbox,
    SecurityPolicy,
)

POLICY = SecurityPolicy(
    pii=PIIConfig(
        enabled=True,
        types=["ssn", "email", "person_name", "credit_card", "phone"],
        action="redact",
        rehydrate_response=False,
    ),
    network=NetworkPolicy(
        allow_out=["httpbin.org"],
        deny_out=[ALL_TRAFFIC],
    ),
    audit=AuditConfig(enabled=True),
)
The probe script POSTs a JSON body containing an SSN, email, and name to httpbin.org/post, which echoes the body back verbatim: 
PROBE = """
import json, ssl, urllib.request

body = json.dumps({
    "ssn": "123-45-6789",
    "email": "alice@example.com",
    "name": "Alice Smith",
}).encode()

ctx = ssl._create_unverified_context()
r = urllib.request.urlopen(
    urllib.request.Request(
        "https://httpbin.org/post",
        data=body,
        headers={"Content-Type": "application/json"},
    ),
    timeout=15,
    context=ctx,
)
echoed = json.loads(r.read().decode())["json"]
print("DEST_SAW:", json.dumps(echoed))
"""
Run the probe inside a sandbox and check the echo: 
sbx = Sandbox.create(template="python", timeout=120, security=POLICY)
try:
    sbx.files.write("/tmp/script.py", PROBE)
    r = sbx.commands.run("python3 /tmp/script.py", timeout=60)
    out = r.stdout or ""
finally:
    sbx.kill()

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Expected output

DEST_SAW: {"ssn": "[REDACTED_SSN]", "email": "[REDACTED_EMAIL]",
           "name": "[REDACTED_PERSON]"}

ssn_redacted=True, email_redacted=True, name_redacted=True
VERDICT  : PASS
All three identifiers are replaced with [REDACTED_*] tokens before the request reaches httpbin. If the SSN passes through unredacted, the probe exits with a non-zero code.

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Full source

See cookbook/examples/pii-ssn-redaction/main.py in the repo.