20250805 関数型DDD 15

Transcript

1. ؔ਺ܕDDD
2. ͓͢͢Ίpoint
3. HonoͷΤϥʔܕͱ૬ੑྑ͠
4. ૝ఆ͞ΕΔΤϥʔ͸ResultͰ ࠷ޙͰऔಘՄೳ
5. const assertNever = (_: never): never => { throw new Error(); }; type DogError = { kind: "DogError"; message: string; }; type CatError = { kind: "CatError"; message: string; }; type AnimalError = DogError | CatError;
6. import { Result, ok, err } from "neverthrow"; const checkAnimal = (animal: string): Result<string, AnimalError> => { if (animal === "Dogn") { return err({ kind: "DogError", message: "Invalid animal" }); } if (animal === "Catn") { return err({ kind: "CatError", message: "Invalid animal" }); } return ok("Animal"); };
7. const app = new Hono(); app.get("/", (c) => { return checkAnimal("Dog").match( (animal) => { return c.json({ message: animal }); }, (error) => { switch (error.kind) { case "DogError": return c.json({ error: `DogError: ${error.message}` }, 401); case "CatError": return c.json({ error: `CatError: ${error.message}` }, 400); default: return assertNever(error); } } ); });
8. ೉͍͠఺
9. ܕͷ໋໊
10. type InactiveUser = { // kind࢖ͬͨ΄͏͕͍͍ʁ id: UserId; email: Email; inactiveAt: InactiveAt; }; type DeletedUser = { // ຊ౰ʹ͜ͷܕ໊Ͱ͍͍ͷ͔ʁ id: UserId; email: Email; deletedAt: DeletedAt; };
11. Step͝ͱʹܕ͕ඞཁ ΋͏࢖͑Δ໊લ͕ͳ͍…
12. ϫʔΫϑϩʔͷαϒες οϓͲ͜Ͱ෼͚Δ͔
13. validateͷதʹcheckEmailͱ checkAddress stepʹ෼͚Δ΂͖͔
14. ݕ౼த
15. ֎͔Βґଘؔ܎Λ஫ೖ͍ͯ͠Δ͕ ͳΔ΂͘७ਮؔ਺ʹอͭ΂͖ʁ
16. Repository૚ͱ͔ͦͷଞґଘؔ ܎ͱ͔΍Γ͗ͯ͢…
17. ४උ෦෼ͷಋೖΛݕ౼ generateͱ͔طଘinviͷऔಘͱ͔
18. ݖݶνΣοΫ
19. ͜Ε͸ผʁ
20. Transaction
21. ΠϕϯτͳΒ͍͍͚Ͳ
22. ϓϩμΫτʹΑͬͯ͸ແ ཧ͔΋
23. ෳ਺ʹ·͕ͨΔૢ࡞ग़ͯ ͘Δʁ
24. ڞ௨Խ͕೉͍͠
25. work f lowͰ׬݁ͯ͠Δ