| export type ApiDecoder<T> = (value: unknown) => T; |
| export type ValueValidator = (value: unknown) => boolean; |
|
|
| export const isString: ValueValidator = (value) => typeof value === "string"; |
| export const isNumber: ValueValidator = (value) => typeof value === "number" && Number.isFinite(value); |
| export const isBoolean: ValueValidator = (value) => typeof value === "boolean"; |
| export const isObject: ValueValidator = (value) => typeof value === "object" && value !== null && !Array.isArray(value); |
|
|
| export function isOptional(validator: ValueValidator): ValueValidator { |
| return (value) => value === undefined || validator(value); |
| } |
|
|
| export function isArrayOf(validator: ValueValidator): ValueValidator { |
| return (value) => Array.isArray(value) && value.every(validator); |
| } |
|
|
| export function isRecordOf(validator: ValueValidator): ValueValidator { |
| return (value) => { |
| if (!isObject(value)) return false; |
| return Object.values(value as Record<string, unknown>).every(validator); |
| }; |
| } |
|
|
| export function isOneOf<const T extends readonly string[]>(...values: T): ValueValidator { |
| return (value) => typeof value === "string" && values.includes(value); |
| } |
|
|
| export function hasShape(shape: Readonly<Record<string, ValueValidator>>): ValueValidator { |
| return (value) => { |
| if (!isObject(value)) return false; |
| const record = value as Record<string, unknown>; |
| return Object.entries(shape).every(([key, validator]) => validator(record[key])); |
| }; |
| } |
|
|
| export function createObjectDecoder<T>(name: string, shape: Readonly<Record<string, ValueValidator>>): ApiDecoder<T> { |
| return createValidatedDecoder(name, hasShape(shape)); |
| } |
|
|
| export function createValidatedDecoder<T>(name: string, validator: ValueValidator): ApiDecoder<T> { |
| return (value) => { |
| if (!validator(value)) throw new Error(`${name} response shape is invalid`); |
| |
| return value as T; |
| }; |
| } |
|
|
| export function decodeBooleanResult<T>(field: string): ApiDecoder<T> { |
| return createObjectDecoder<T>("boolean result", { [field]: isBoolean }); |
| } |
|
|
| export function decodeCountResult<T>(field: string): ApiDecoder<T> { |
| return createObjectDecoder<T>("count result", { [field]: isNumber }); |
| } |
|
|
| export function createPaginatedDecoder<T>(itemValidator: ValueValidator): ApiDecoder<{ items: T[]; page: number; pageSize: number; total: number }> { |
| return createObjectDecoder("paginated result", { |
| items: isArrayOf(itemValidator), |
| page: isNumber, |
| pageSize: isNumber, |
| total: isNumber, |
| }); |
| } |
|
|
