ParseFloatPipeOptions

Kind: Interface

Source: packages/common/pipes/parse-float.pipe.ts

Part of: Common

ParseFloatPipeOptions configures the behavior of a float-parsing pipe. It controls whether missing values are accepted, which HTTP status code is used for validation failures, and how parsing errors are converted into exceptions.

Properties

Diagram

mermaid
graph LR
  Input[Incoming value] --> Pipe[ParseFloatPipe]
  Pipe --> Optional{optional enabled?}
  Optional -->|Empty value allowed| Result[Return empty value]
  Optional -->|Value required| Parse[Parse numeric float]
  Parse -->|Valid float| Result2[Return parsed number]
  Parse -->|Invalid value| Factory[exceptionFactory]
  Factory --> Error[Throw exception with errorHttpStatusCode]

Usage

ts
import { ParseFloatPipe } from '@nestjs/common';
import type { ParseFloatPipeOptions } from '@nestjs/common';

const options: ParseFloatPipeOptions = {
  optional: false,
  errorHttpStatusCode: 422,
  exceptionFactory: (error: string) => ({
    statusCode: 422,
    message: `Invalid price: ${error}`,
  }),
};

const parsePrice = new ParseFloatPipe(options);

// Example controller usage:
// @Query('price', parsePrice) price: number

AI Coding Instructions

• Use optional: true only when empty or missing values should bypass float validation.
• Provide an exceptionFactory when the default validation exception format does not match the application's error contract.
• Ensure errorHttpStatusCode aligns with API validation conventions, such as 400 or 422.
• Treat successfully transformed values as JavaScript number values and validate domain-specific constraints separately.

How it works

ParseFloatPipeOptions is the optional constructor-configuration interface for ParseFloatPipe. It has three optional fields: errorHttpStatusCode, exceptionFactory, and optional.

• errorHttpStatusCode accepts the ErrorHttpStatusCode union, which is limited to the HTTP status codes mapped to exception classes in HttpErrorByCode. packages/common/utils/http-error-by-code.util.ts:27-48 packages/common/utils/http-error-by-code.util.ts:50-72
• exceptionFactory accepts a function receiving an error string and returning the value that ParseFloatPipe throws when validation fails. packages/common/pipes/parse-float.pipe.ts:19-24 packages/common/pipes/parse-float.pipe.ts:64-67
• optional, when truthy, causes the pipe to return an input that is null or undefined without numeric validation or parsing. isNil identifies exactly null and undefined. packages/common/pipes/parse-float.pipe.ts:25-29 packages/common/pipes/parse-float.pipe.ts:60-63 packages/common/utils/shared.utils.ts:48-49

When no exceptionFactory is configured, ParseFloatPipe creates one that constructs the exception class selected by errorHttpStatusCode; that status defaults to HttpStatus.BAD_REQUEST. packages/common/pipes/parse-float.pipe.ts:43-50 If numeric validation fails, the factory receives the fixed message Validation failed (numeric string is expected). packages/common/pipes/parse-float.pipe.ts:64-67

The associated pipe accepts values whose runtime type is string or number, whose parseFloat result is not NaN, and which are finite; valid values are returned as parseFloat(value). packages/common/pipes/parse-float.pipe.ts:60-69 packages/common/pipes/parse-float.pipe.ts:76-81