Add DateFromString or use DateFromISOString

[ecamellini]

requirements

At the moment, to convert Instant, LocalDateTime, etc into JS Dates, we need to manually map them to Date in the prelude in metarpheus config and to manually define and include also a DateFromString io-ts type: we could include all this in metarpehus:

• Definition of DateFromString (or use some already existing type like DateFromISOString
• Mapping of common types to Date and DateFromString

specs

At the moment, this is what we add to the prelude in projects:

const dateFromString = `
export const DateFromString = new t.Type<Date, string>(
  'Date',
  (v): v is Date => v instanceof Date,
  (v, c) =>
    t.string.validate(v, c).chain(s => {
      const d = new Date(s)
      return isNaN(d.getTime()) ? t.failure(s, c) : t.success(d)
    }),
  a => a.toISOString()
)
`;

const modelPrelude = `
${dateFromString}
export type Instant = Date;
export const Instant = DateFromString;
export type LocalDateTime = Date;
export const LocalDateTime = DateFromString;
export type LocalDate = Date;
export const LocalDate = DateFromString;
export type LocalTime = Date;
export const LocalTime = DateFromString;

misc

{optional: other useful info}

[gabro]

DateFromISOString implementation looks identical, so I would just pull it in and use it.

https://github.com/gcanti/io-ts-types/blob/master/src/Date/DateFromISOString.ts

[giogonzo]

@ecamellini LocalDate and LocalDateTime should use https://github.com/buildo/local-date though