kos/pkg/request/client.go

package request

import (
	"bytes"
	"io"
	"net/http"
	"net/http/cookiejar"
	"strings"
)

type (
	BeforeRequest func(req *http.Request) (err error)
	AfterRequest  func(req *http.Request, res *http.Response) (err error)

	Client struct {
		baseUrl             string
		Authorization       Authorization
		client              *http.Client
		cookieJar           *cookiejar.Jar
		interceptorRequest  []BeforeRequest
		interceptorResponse []AfterRequest
	}
)

func (client *Client) stashUri(urlPath string) string {
	var (
		pos int
	)
	if len(urlPath) == 0 {
		return client.baseUrl
	}
	if pos = strings.Index(urlPath, "//"); pos == -1 {
		if client.baseUrl != "" {
			if urlPath[0] != '/' {
				urlPath = "/" + urlPath
			}
			return client.baseUrl + urlPath
		}
	}
	return urlPath
}

func (client *Client) BeforeRequest(cb BeforeRequest) *Client {
	client.interceptorRequest = append(client.interceptorRequest, cb)
	return client
}

func (client *Client) AfterRequest(cb AfterRequest) *Client {
	client.interceptorResponse = append(client.interceptorResponse, cb)
	return client
}

func (client *Client) SetBaseUrl(s string) *Client {
	client.baseUrl = strings.TrimSuffix(s, "/")
	return client
}

func (client *Client) SetCookieJar(cookieJar *cookiejar.Jar) *Client {
	client.client.Jar = cookieJar
	return client
}

func (client *Client) SetClient(httpClient *http.Client) *Client {
	client.client = httpClient
	if client.cookieJar != nil {
		client.client.Jar = client.cookieJar
	}
	return client
}

func (client *Client) SetTransport(transport http.RoundTripper) *Client {
	client.client.Transport = transport
	return client
}

func (client *Client) Get(urlPath string) *Request {
	return newRequest(http.MethodGet, client.stashUri(urlPath), client)
}

func (client *Client) Put(urlPath string) *Request {
	return newRequest(http.MethodPut, client.stashUri(urlPath), client)
}

func (client *Client) Post(urlPath string) *Request {
	return newRequest(http.MethodPost, client.stashUri(urlPath), client)
}

func (client *Client) Delete(urlPath string) *Request {
	return newRequest(http.MethodDelete, client.stashUri(urlPath), client)
}

func (client *Client) execute(r *Request) (res *http.Response, err error) {
	var (
		n      int
		buf    []byte
		reader io.Reader
	)
	if r.contentType == "" && r.body != nil {
		r.contentType = r.detectContentType(r.body)
	}
	if r.body != nil {
		if buf, err = r.readRequestBody(r.contentType, r.body); err != nil {
			return
		}
		reader = bytes.NewReader(buf)
	}
	if r.rawRequest, err = http.NewRequest(r.method, r.uri, reader); err != nil {
		return
	}
	for k, vs := range r.header {
		for _, v := range vs {
			r.rawRequest.Header.Add(k, v)
		}
	}
	if r.contentType != "" {
		r.rawRequest.Header.Set("Content-Type", r.contentType)
	}
	if client.Authorization != nil {
		r.rawRequest.Header.Set("Authorization", client.Authorization.Token())
	}
	if r.context != nil {
		r.rawRequest = r.rawRequest.WithContext(r.context)
	}
	n = len(client.interceptorRequest)
	for i := n - 1; i >= 0; i-- {
		if err = client.interceptorRequest[i](r.rawRequest); err != nil {
			return
		}
	}
	if r.rawResponse, err = client.client.Do(r.rawRequest); err != nil {
		return nil, err
	}
	n = len(client.interceptorResponse)
	for i := n - 1; i >= 0; i-- {
		if err = client.interceptorResponse[i](r.rawRequest, r.rawResponse); err != nil {
			_ = r.rawResponse.Body.Close()
			return
		}
	}
	return r.rawResponse, err
}

func New() *Client {
	client := &Client{
		client:              http.DefaultClient,
		interceptorRequest:  make([]BeforeRequest, 0, 10),
		interceptorResponse: make([]AfterRequest, 0, 10),
	}
	client.cookieJar, _ = cookiejar.New(nil)
	client.client.Jar = client.cookieJar
	return client
}