pydantic-deep-patch

⚡️ Deep diffing, RFC 6902 JSON-Patch, RFC 7396 Merge-Patch, and type-safe audit logging for Pydantic v2 models.

💡 Why pydantic-deep-patch?

Handling partial API updates (PATCH /items/{id}) and tracking audit logs across nested Pydantic v2 models is usually painful and repetitive.

pydantic-deep-patch provides:

• 🔍 RFC 6902 JSON-Patch: Generate standard JSON Patch operations (add, remove, replace) between any two Pydantic model instances.
• 🛠 Safe Model Application (apply_patch): Apply patches with automatic Pydantic v2 validation.
• 📋 Human-Readable Audit Trails (diff_audit): Generate human-readable change logs for database audits or UI activity feeds.
• 🔄 RFC 7396 Merge-Patch (merge_patch): Support standard JSON Merge-Patch dictionaries.

📦 Installation

pip install pydantic-deep-patch

🚀 Quick Usage

from pydantic import BaseModel
from pydantic_deep_patch import diff, apply_patch, diff_audit, merge_patch

class Profile(BaseModel):
    name: str
    age: int

class User(BaseModel):
    id: str
    profile: Profile

# 1. Compute RFC 6902 Diffs
u1 = User(id="1", profile=Profile(name="Alice", age=25))
u2 = User(id="1", profile=Profile(name="Alice", age=26))

patch_ops = diff(u1, u2)
# Output: [PatchOp(op='replace', path='/profile/age', value=26)]

# 2. Apply patch to update a model
updated_user = apply_patch(u1, patch_ops)

# 3. Generate Audit Log
audit_log = diff_audit(u1, u2)
# Output: [AuditEntry(field_name='age', action='modified', description="Field 'age' changed from 25 to 26")]

# 4. JSON Merge Patch (RFC 7396)
updated_merge = merge_patch(u1, {"profile": {"name": "Alice Smith"}})

📄 License

MIT © Raj Dubey