honojs-middleware/packages/zod-validator/src/index.ts

111 lines
3.8 KiB
TypeScript

/* eslint-disable @typescript-eslint/no-explicit-any */
import type { Context, Env, Input, MiddlewareHandler, TypedResponse, ValidationTargets } from 'hono'
import { validator } from 'hono/validator'
import type * as v3 from 'zod'
import type { ZodSafeParseResult as v4ZodSafeParseResult } from 'zod/v4'
import type * as v4 from 'zod/v4/core'
type ZodSchema = v3.ZodType | v4.$ZodType
type ZodError<T extends ZodSchema> = T extends v4.$ZodType ? v4.$ZodError : v3.ZodError
type ZodSafeParseResult<T, T2, T3 extends ZodSchema> = T3 extends v4.$ZodType
? v4ZodSafeParseResult<T>
: v3.SafeParseReturnType<T, T2>
type zInput<T> = T extends v3.ZodType ? v3.input<T> : T extends v4.$ZodType ? v4.input<T> : never
type zOutput<T> = T extends v3.ZodType ? v3.output<T> : T extends v4.$ZodType ? v4.output<T> : never
type zInfer<T> = T extends v3.ZodType ? v3.infer<T> : T extends v4.$ZodType ? v4.infer<T> : never
export type Hook<
T,
E extends Env,
P extends string,
Target extends keyof ValidationTargets = keyof ValidationTargets,
O = {},
Schema extends ZodSchema = any,
> = (
result: ({ success: true; data: T } | { success: false; error: ZodError<Schema>; data: T }) & {
target: Target
},
c: Context<E, P>
) => Response | void | TypedResponse<O> | Promise<Response | void | TypedResponse<O>>
type HasUndefined<T> = undefined extends T ? true : false
export const zValidator = <
T extends ZodSchema,
Target extends keyof ValidationTargets,
E extends Env,
P extends string,
In = zInput<T>,
Out = zOutput<T>,
I extends Input = {
in: HasUndefined<In> extends true
? {
[K in Target]?: In extends ValidationTargets[K]
? In
: { [K2 in keyof In]?: ValidationTargets[K][K2] }
}
: {
[K in Target]: In extends ValidationTargets[K]
? In
: { [K2 in keyof In]: ValidationTargets[K][K2] }
}
out: { [K in Target]: Out }
},
V extends I = I,
InferredValue = zInfer<T>,
>(
target: Target,
schema: T,
hook?: Hook<InferredValue, E, P, Target, {}, T>,
options?: {
validationFunction: (
schema: T,
value: ValidationTargets[Target]
) => ZodSafeParseResult<any, any, T> | Promise<ZodSafeParseResult<any, any, T>>
}
): MiddlewareHandler<E, P, V> =>
// @ts-expect-error not typed well
validator(target, async (value, c) => {
let validatorValue = value
// in case where our `target` === `header`, Hono parses all of the headers into lowercase.
// this might not match the Zod schema, so we want to make sure that we account for that when parsing the schema.
if ((target === 'header' && '_def' in schema) || (target === 'header' && '_zod' in schema)) {
// create an object that maps lowercase schema keys to lowercase
// @ts-expect-error the schema is a Zod Schema
const schemaKeys = Object.keys(schema.shape)
const caseInsensitiveKeymap = Object.fromEntries(
schemaKeys.map((key) => [key.toLowerCase(), key])
)
validatorValue = Object.fromEntries(
Object.entries(value).map(([key, value]) => [caseInsensitiveKeymap[key] || key, value])
)
}
const result =
options && options.validationFunction
? await options.validationFunction(schema, validatorValue)
: // @ts-expect-error z4.$ZodType has safeParseAsync
await schema.safeParseAsync(validatorValue)
if (hook) {
const hookResult = await hook({ data: validatorValue, ...result, target }, c)
if (hookResult) {
if (hookResult instanceof Response) {
return hookResult
}
if ('response' in hookResult) {
return hookResult.response
}
}
}
if (!result.success) {
return c.json(result, 400)
}
return result.data as zInfer<T>
})