local-functions/main.go
Knut Ahlers 89916ea9b5
Initial version
Signed-off-by: Knut Ahlers <knut@ahlers.me>
2020-10-02 01:06:07 +02:00

90 lines
2 KiB
Go

package main
import (
"bytes"
"fmt"
"io"
"net/http"
"os"
"os/exec"
"path"
"github.com/gorilla/mux"
log "github.com/sirupsen/logrus"
"github.com/Luzifer/go_helpers/v2/env"
httpHelper "github.com/Luzifer/go_helpers/v2/http"
"github.com/Luzifer/rconfig/v2"
)
var (
cfg = struct {
Listen string `flag:"listen" default:"127.0.0.1:3000" description:"Port/IP to listen on"`
LogLevel string `flag:"log-level" default:"info" description:"Log level (debug, info, warn, error, fatal)"`
ScriptDir string `flag:"script-dir" default:"./scripts" description:"Directory to execute the script / binary from"`
VersionAndExit bool `flag:"version" default:"false" description:"Prints current version and exits"`
}{}
version = "dev"
)
func init() {
rconfig.AutoEnv(true)
if err := rconfig.ParseAndValidate(&cfg); err != nil {
log.Fatalf("Unable to parse commandline options: %s", err)
}
if cfg.VersionAndExit {
fmt.Printf("local-functions %s\n", version)
os.Exit(0)
}
if l, err := log.ParseLevel(cfg.LogLevel); err != nil {
log.WithError(err).Fatal("Unable to parse log level")
} else {
log.SetLevel(l)
}
}
func main() {
r := mux.NewRouter()
r.HandleFunc("/{script}", handleScriptCall)
var h http.Handler = r
h = httpHelper.NewHTTPLogHandler(h)
http.ListenAndServe(cfg.Listen, h)
}
func handleScriptCall(w http.ResponseWriter, r *http.Request) {
var (
vars = mux.Vars(r)
script = path.Join(cfg.ScriptDir, vars["script"])
)
if _, err := os.Stat(script); vars["script"] == "" || os.IsNotExist(err) {
http.Error(w, "Not found", http.StatusNotFound)
return
}
var (
stdout = new(bytes.Buffer)
cmd = exec.Command(script)
)
cmd.Stdout = stdout
cmd.Stderr = os.Stderr
cmd.Stdin = r.Body
cmd.Env = env.MapToList(map[string]string{
"ACCEPT": r.Header.Get("Accept"),
"CONTENT_TYPE": r.Header.Get("Content-Type"),
"METHOD": r.Method,
})
if err := cmd.Run(); err != nil {
http.Error(w, "Script execution failed, see log", http.StatusInternalServerError)
return
}
io.Copy(w, stdout)
}