Rssmon2/fetch/fetch.go

108 lines
2.2 KiB
Go

package fetch
import (
"context"
"fmt"
"io/ioutil"
"local1/logger"
"net/http"
"time"
)
type Fetch struct {
process func(string, []byte) error
client *http.Client
server *http.Server
port string
}
func New(port string, process func(string, []byte) error) (*Fetch, error) {
return &Fetch{
process: process,
client: &http.Client{},
port: port,
}, nil
}
func (fetcher *Fetch) FetchProcess(url string) error {
req, err := http.NewRequest("GET", url, nil)
if err != nil {
return err
}
resp, err := fetcher.client.Do(req)
if err != nil {
return err
}
defer resp.Body.Close()
b, err := ioutil.ReadAll(resp.Body)
if err != nil {
return err
}
if err := fetcher.process(url, b); err != nil {
return err
}
return nil
}
func (fetcher *Fetch) listen() error {
fetcher.server = &http.Server{
Addr: fetcher.port,
Handler: http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
if r.URL.Path != "/fetchfeed" {
http.NotFound(w, r)
logger.Logf("bad path: %q", r.URL.Path)
return
}
if r.Method != "POST" && r.Method != "PUT" {
http.NotFound(w, r)
logger.Logf("bad method: %q", r.Method)
return
}
b, err := ioutil.ReadAll(r.Body)
defer r.Body.Close()
if err != nil || len(b) == 0 {
logger.Log(len(b), err)
w.WriteHeader(http.StatusBadRequest)
return
}
if err := fetcher.FetchProcess(string(b)); err != nil {
w.WriteHeader(http.StatusInternalServerError)
return
}
}),
}
if err := fetcher.server.ListenAndServe(); err != http.ErrServerClosed && err != nil {
return err
}
return nil
}
func (fetcher *Fetch) Start() error {
errs := make(chan error)
go func() {
if err := fetcher.listen(); err != nil {
select {
case errs <- err:
case <-time.After(time.Second * 10):
panic(err)
}
}
}()
select {
case err := <-errs:
return fmt.Errorf("%s: %v", "fetcher server quit early", err)
case <-time.After(time.Second * 10):
}
return nil
}
func (fetcher *Fetch) Close() error {
return fetcher.Stop()
}
func (fetcher *Fetch) Stop() error {
ctx, can := context.WithTimeout(context.Background(), time.Second*10)
defer can()
return fetcher.server.Shutdown(ctx)
}