acceptsOptions

Kind: Interface

Source: src/helper/accepts/accepts.ts

Part of: Helper

acceptsOptions defines the contract for matching a list of Accept values against an acceptsConfig. Its match method receives the available accept entries and configuration, then returns the selected value as a string.

Properties

Diagram

mermaid
graph LR
  A[Accept[]] --> C[acceptsOptions.match]
  B[acceptsConfig] --> C
  C --> D[string]

Usage

ts
import type { acceptsOptions } from './src/helper/accepts/accepts';

const options: acceptsOptions = {
  match(accepts, config) {
    const match = accepts.find((accept) => accept.type === config.type);

    return match?.type ?? '';
  },
};

const selected = options.match(accepts, config);

AI Coding Instructions

• Implement match with both the Accept[] input and acceptsConfig input in mind.
• Return a string for every match path, including when no Accept entry matches.
• Keep matching rules consistent with the Accept and acceptsConfig types used by the accepts helper.
• Avoid mutating the incoming accepts array or config object during matching.

How it works

acceptsOptions is the options interface accepted by accepts(c, options). It extends acceptsConfig, so callers must set:

• header: one of 'Accept', 'Accept-Charset', 'Accept-Encoding', 'Accept-Language', 'Accept-Patch', 'Accept-Post', or 'Accept-Ranges'. src/helper/accepts/accepts.ts:11-18 src/utils/headers.ts:345-352
• supports: an array of strings against which parsed accept-value type fields are compared. src/helper/accepts/accepts.ts:11-15 src/helper/accepts/accepts.ts:21-24
• default: the string returned when the configured request header is absent or when the selected matcher finds no supported type. src/helper/accepts/accepts.ts:14 src/helper/accepts/accepts.ts:42-44 src/helper/accepts/accepts.ts:21-24

It optionally accepts match, a function with the signature (accepts: Accept[], config: acceptsConfig) => string. src/helper/accepts/accepts.ts:17-19 accepts reads options.header from the request, parses its value, and calls this function with the parsed values and the same options object when match is set; otherwise it calls defaultMatch. src/helper/accepts/accepts.ts:40-48

Each element passed as the first match argument has type, params, and numeric q fields. src/helper/accepts/accepts.ts:5-9 The parser initializes missing quality values to 1, reads a q parameter when present, and returns an array of parsed values. src/utils/accept.ts:163-167 src/utils/accept.ts:211-237

Without a custom match, defaultMatch sorts the parsed array by descending q, returns the first entry whose type occurs in supports, and otherwise returns default. src/helper/accepts/accepts.ts:21-25 A custom matcher can choose different selection rules; the test demonstrates one that sorts ascending by q and returns the first supported type. src/helper/accepts/accepts.test.ts:89-112

There is no runtime validation of header, supports, default, or the return value of match in this code. If the request header is falsy, accepts returns default immediately and does not parse the header or call match. src/helper/accepts/accepts.ts:41-48