lambda/task/http_request.go

package task

import (
	"encoding/json"
	"encoding/xml"
	"fmt"
	"io"
	"net/http"
)

type DecoderFunc func(r io.Reader) Decoder

type Decoder interface {
	Decode(any) error
}

type HttpRequest[T any] struct {
	Req http.Request
	ans T
	err error
}

func (r *HttpRequest[T]) Ans() T {
	return r.ans
}

func (r *HttpRequest[T]) Err() error {
	return r.err
}

func (r *HttpRequest[T]) String() string {
	return fmt.Sprintf("%+v", r.ans)
}

func (_ *HttpRequest[T]) NoErr() func(r *HttpRequest[T]) bool {
	return func(r *HttpRequest[T]) bool {
		return r.err == nil
	}
}

func (_ *HttpRequest[T]) With(df DecoderFunc) func(r *HttpRequest[T]) *HttpRequest[T] {
	return func(r *HttpRequest[T]) *HttpRequest[T] {
		r.ans = *new(T)
		res, err := http.DefaultClient.Do(&r.Req)
		if err != nil {
			r.err = err
			return r
		}
		defer res.Body.Close()
		r.err = df(res.Body).Decode(&r.ans)
		return r
	}
}

func (z *HttpRequest[T]) Json() func(r *HttpRequest[T]) *HttpRequest[T] {
	return z.With(func(r io.Reader) Decoder {
		return json.NewDecoder(r)
	})
}

func (z *HttpRequest[T]) Xml() func(r *HttpRequest[T]) *HttpRequest[T] {
	return z.With(func(r io.Reader) Decoder {
		return xml.NewDecoder(r)
	})
}