Class: DerivedFactWriteError

@kortexya/reasoninglayer / DerivedFactWriteError

Class: DerivedFactWriteError

Defined in: src/errors.ts:190

A write onto a DERIVED FACT — a conclusion a rule materialized — refused (HTTP 409, code: "write_targets_derived_fact").

Remarks

A derived term changes when its premises do, so a write onto it cannot stand. A write onto the rule’s own term (its conclusion template, an antecedent pattern or a variable) is a different refusal: RuleTermWriteError. The engine refuses it on PUT /api/v1/terms/{id}, DELETE /api/v1/terms/{id} and POST /api/v1/inference/facts/bulk-retract (the whole batch is refused, nothing is removed), and names the rule that derived the term and the writes that WOULD work.

The check runs before If-Match is read: a conclusion carries no ETag, so a write onto one answers this error and never a PreconditionFailedError.

Extends ConstraintViolationError, so a handler that already catches every 409 keeps catching it.

Example

try {
  await client.terms.updateTerm(termId, { features: { tier: 'gold' } });
} catch (e) {
  if (e instanceof DerivedFactWriteError) {
    console.log(`derived by rule ${e.derivedBy}`);
    for (const repair of e.repairs) console.log(repair.kind, repair.rewrite);
  }
}

Extends

ConstraintViolationError

Constructors

Constructor

new DerivedFactWriteError(message, body, headers, termId, derivedBy, repairs, errorCode?): DerivedFactWriteError

Defined in: src/errors.ts:203

Parameters

message

string

body

unknown

headers

Headers

termId

string | undefined

derivedBy

string | undefined

repairs

readonly DerivedFactRepair[]

errorCode?

string

Returns

DerivedFactWriteError

Overrides

ConstraintViolationError.constructor

Properties

body

readonly body: unknown

Defined in: src/errors.ts:55

Parsed response body.

Inherited from

ConstraintViolationError.body

cause?

optional cause?: unknown

Defined in: node_modules/.pnpm/typescript@5.9.3/node_modules/typescript/lib/lib.es2022.error.d.ts:26

Inherited from

ConstraintViolationError.cause

code

readonly code: "write_targets_derived_fact"

Defined in: src/errors.ts:194

The refusal code. Always write_targets_derived_fact.

constraint

readonly constraint: string | undefined

Defined in: src/errors.ts:140

Constraint description, if available.

Inherited from

ConstraintViolationError.constraint

derivedBy

readonly derivedBy: string | undefined

Defined in: src/errors.ts:196

The rule that derived the term, when the engine names one.

errorCode

readonly errorCode: string | undefined

Defined in: src/errors.ts:53

Backend error code (from response body error field), if present.

Inherited from

ConstraintViolationError.errorCode

feature

readonly feature: string | undefined

Defined in: src/errors.ts:138

Feature name that violated the constraint, if available.

Inherited from

ConstraintViolationError.feature

headers

readonly headers: Headers

Defined in: src/errors.ts:57

Response headers.

Inherited from

ConstraintViolationError.headers

message

message: string

Defined in: node_modules/.pnpm/typescript@5.9.3/node_modules/typescript/lib/lib.es5.d.ts:1077

Inherited from

ConstraintViolationError.message

name

name: string = 'DerivedFactWriteError'

Defined in: src/errors.ts:191

Overrides

ConstraintViolationError.name

repairs

readonly repairs: readonly DerivedFactRepair[]

Defined in: src/errors.ts:201

What to write instead: retract or update an asserted premise, or withdraw the rule. Empty when the engine found no justification to name.

stack?

optional stack?: string

Defined in: node_modules/.pnpm/typescript@5.9.3/node_modules/typescript/lib/lib.es5.d.ts:1078

Inherited from

ConstraintViolationError.stack

status

readonly status: number

Defined in: src/errors.ts:51

HTTP status code.

Inherited from

ConstraintViolationError.status

termId

readonly termId: string | undefined

Defined in: src/errors.ts:136

Term ID that violated the constraint, if available.

Inherited from

ConstraintViolationError.termId

stackTraceLimit

static stackTraceLimit: number

Defined in: node_modules/.pnpm/@types+node@24.13.3/node_modules/@types/node/globals.d.ts:68

The Error.stackTraceLimit property specifies the number of stack frames collected by a stack trace (whether generated by new Error().stack or Error.captureStackTrace(obj)).

The default value is 10 but may be set to any valid JavaScript number. Changes will affect any stack trace captured after the value has been changed.

If set to a non-number value, or set to a negative number, stack traces will not capture any frames.

Inherited from

ConstraintViolationError.stackTraceLimit

Methods

captureStackTrace()

static captureStackTrace(targetObject, constructorOpt?): void

Defined in: node_modules/.pnpm/@types+node@24.13.3/node_modules/@types/node/globals.d.ts:52

Creates a .stack property on targetObject, which when accessed returns a string representing the location in the code at which Error.captureStackTrace() was called.

const myObject = {};
Error.captureStackTrace(myObject);
myObject.stack;  // Similar to `new Error().stack`

The first line of the trace will be prefixed with ${myObject.name}: ${myObject.message}.

The optional constructorOpt argument accepts a function. If given, all frames above constructorOpt, including constructorOpt, will be omitted from the generated stack trace.

The constructorOpt argument is useful for hiding implementation details of error generation from the user. For instance:

function a() {
  b();
}

function b() {
  c();
}

function c() {
  // Create an error without stack trace to avoid calculating the stack trace twice.
  const { stackTraceLimit } = Error;
  Error.stackTraceLimit = 0;
  const error = new Error();
  Error.stackTraceLimit = stackTraceLimit;

  // Capture the stack trace above function b
  Error.captureStackTrace(error, b); // Neither function c, nor b is included in the stack trace
  throw error;
}

a();

Parameters

targetObject

object

constructorOpt?

Function

Returns

void

Inherited from

ConstraintViolationError.captureStackTrace

prepareStackTrace()

static prepareStackTrace(err, stackTraces): any

Defined in: node_modules/.pnpm/@types+node@24.13.3/node_modules/@types/node/globals.d.ts:56

Parameters

err

Error

stackTraces

CallSite[]

Returns

any

See

https://v8.dev/docs/stack-trace-api#customizing-stack-traces

Inherited from

ConstraintViolationError.prepareStackTrace