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ContractModel

The ContractModel class is the abstract base for all ACTUS contract types in the Awesome Actus Library. It defines the structure, validation, and lifecycle behavior of ACTUS-conformant financial contracts such as PAM, ANN, LAM, etc.

All contract types like PAM inherit from ContractModel, which centralizes term management, validation, and internal representation.

🌍 Purpose​

  • Standardizes how contract terms are structured, stored, and validated
  • Handles the lifecycle of contract input validation
  • Enforces ACTUS time consistency rules
  • Enables extension with user-defined terms

✏️ Structure​

Each ContractModel holds contract terms in a dictionary:

self.terms = {
  "contractID": ContractID("PAM-001"),
  "notionalPrincipal": NotionalPrincipal(10000.0),
  # ...
}
  • Keys are the term identifiers (e.g. contractID, notionalPrincipal)
  • Values are instances of subclasses of ContractTerm

🛠️ TermBuilder Utility​

Inside the model, a helper class TermBuilder is used to dynamically construct the correct term class based on the name:

builder = self.TermBuilder(self.terms)
builder.add("notionalPrincipal", 10000.0)

This maps a field like notionalPrincipal to the correct term class (e.g., NotionalPrincipal).

🔢 Term Access​

Get a Term​

model.get_term("maturityDate")

Serialize to Dictionary​

model.to_dict()

Useful for exporting to JSON or saving contract data.

⚠️ Time Consistency Rules​

The ContractModel enforces ACTUS time ordering constraints via check_time_consistency_rules(). This includes checks like:

  • contractDealDate <= initialExchangeDate <= maturityDate
  • cycleAnchorDateOfInterestPayment < maturityDate
  • optionExerciseEndDate <= maturityDate

Warnings are printed if rules are violated.

🌐 User-Defined Terms​

If you add a custom term not in the ACTUS standard, the model can still accept it:

pam = PAM(..., myCustomField="customValue")

These are wrapped using a fallback UserDefinedTerm and stored normally in self.terms.

✅ Required Method​

validate_terms() (abstract)​

Each subclass (e.g. PAM, ANN) must implement validate_terms() to:

  • Check ACTUS group dependencies
  • Raise errors for missing fields

🔗 See Also​