Files
go-zero/rest/httpc/service.go
2025-12-25 21:39:45 +08:00

114 lines
2.8 KiB
Go

package httpc
import (
"context"
"errors"
"net"
"net/http"
"net/url"
"github.com/zeromicro/go-zero/core/breaker"
)
type (
// Option is used to customize the *http.Client.
Option func(r *http.Request) *http.Request
// Service represents a remote HTTP service.
Service interface {
// Do sends an HTTP request with the given arguments and returns an HTTP response.
Do(ctx context.Context, method, url string, data any) (*http.Response, error)
// DoRequest sends a HTTP request to the service.
DoRequest(r *http.Request) (*http.Response, error)
}
namedService struct {
name string
cli *http.Client
opts []Option
}
)
// NewService returns a remote service with the given name.
// opts are used to customize the *http.Client.
func NewService(name string, opts ...Option) Service {
return NewServiceWithClient(name, http.DefaultClient, opts...)
}
// NewServiceWithClient returns a remote service with the given name.
// opts are used to customize the *http.Client.
func NewServiceWithClient(name string, cli *http.Client, opts ...Option) Service {
return namedService{
name: name,
cli: cli,
opts: opts,
}
}
// Do sends an HTTP request with the given arguments and returns an HTTP response.
func (s namedService) Do(ctx context.Context, method, url string, data any) (*http.Response, error) {
req, err := buildRequest(ctx, method, url, data)
if err != nil {
return nil, err
}
return s.DoRequest(req)
}
// DoRequest sends an HTTP request to the service.
func (s namedService) DoRequest(r *http.Request) (*http.Response, error) {
return request(r, s)
}
func (s namedService) do(r *http.Request) (resp *http.Response, err error) {
for _, opt := range s.opts {
r = opt(r)
}
brk := breaker.GetBreaker(s.name)
err = brk.DoWithAcceptableCtx(r.Context(), func() error {
resp, err = s.cli.Do(r)
return err
}, func(err error) bool {
return acceptable(resp, err)
})
return
}
// acceptable determines whether the HTTP request/response should be considered
// successful for circuit breaker purposes.
//
// Returns true (acceptable) for:
// - HTTP status codes < 500 (2xx, 3xx, 4xx)
// - Context cancellation (user-initiated)
// - Non-network errors (application-level errors)
//
// Returns false (not acceptable, triggers breaker) for:
// - HTTP status codes >= 500 (server errors)
// - context.DeadlineExceeded (timeout)
// - Network errors (connection refused, DNS failures, etc.)
func acceptable(resp *http.Response, err error) bool {
if err == nil {
return resp.StatusCode < http.StatusInternalServerError
}
if errors.Is(err, context.DeadlineExceeded) {
return false
}
if errors.Is(err, context.Canceled) {
return true
}
// Unwrap url.Error if present
var ue *url.Error
if errors.As(err, &ue) {
err = ue.Unwrap()
}
// Network errors are not acceptable
var ne net.Error
return !errors.As(err, &ne)
}