ussd/http/server.go
2024-09-06 00:40:57 +01:00

122 lines
2.5 KiB
Go

package http
import (
"fmt"
"io/ioutil"
"net/http"
"os"
"git.defalsify.org/vise.git/db"
"git.defalsify.org/vise.git/engine"
"git.defalsify.org/vise.git/persist"
"git.defalsify.org/vise.git/resource"
)
type RequestParser struct {
}
func(rp *RequestParser) GetSessionId(rq *http.Request) (string, error) {
v := rq.Header.Get("X-Vise-Session")
if v == "" {
return "", fmt.Errorf("no session found")
}
return v, nil
}
func(rp *RequestParser) GetInput(rq *http.Request) ([]byte, error) {
defer rq.Body.Close()
v, err := ioutil.ReadAll(rq.Body)
if err != nil {
return nil, err
}
return v, nil
}
type SessionHandler struct {
cfgTemplate engine.Config
rp RequestParser
rs resource.Resource
first resource.EntryFunc
}
func NewSessionHandler(cfg engine.Config, rs resource.Resource, userdataDb db.Db, first resource.EntryFunc) *SessionHandler {
return &SessionHandler{
cfgTemplate: cfg,
rs: rs,
first: first,
rp: RequestParser{},
}
}
func(f *SessionHandler) writeError(w http.ResponseWriter, code int, msg string, err error) {
w.Header().Set("X-Vise", msg + ": " + err.Error())
w.Header().Set("Content-Length", "0")
w.WriteHeader(code)
_, err = w.Write([]byte{})
if err != nil {
w.WriteHeader(500)
w.Header().Set("X-Vise", err.Error())
}
return
}
func(f *SessionHandler) ServeHTTP(w http.ResponseWriter, req *http.Request) {
var r bool
sessionId, err := f.rp.GetSessionId(req)
if err != nil {
f.writeError(w, 400, "Session missing", err)
return
}
input, err := f.rp.GetInput(req)
if err != nil {
f.writeError(w, 400, "Input read fail", err)
return
}
ctx := req.Context()
cfg := f.cfgTemplate
cfg.SessionId = sessionId
en := getEngine(cfg, f.rs, f.pr)
en = en.WithFirst(f.first)
if cfg.EngineDebug {
en = en.WithDebug(nil)
}
if len(input) == 0 {
r, err = en.Init(ctx)
} else {
r, err = en.Exec(ctx, input)
}
_, err = en.Init(ctx)
if err != nil {
fmt.Fprintf(os.Stderr, "engine init exited with error: %v\n", err)
os.Exit(1)
}
if err != nil {
f.writeError(w, 500, "Engine exec fail", err)
return
}
w.WriteHeader(200)
w.Header().Set("Content-Type", "text/plain")
_, err = en.WriteResult(ctx, w)
if err != nil {
f.writeError(w, 500, "Write result fail", err)
return
}
err = en.Finish()
if err != nil {
f.writeError(w, 500, "Engine finish fail", err)
return
}
_ = r
}
func getEngine(cfg engine.Config, rs resource.Resource, pr *persist.Persister) *engine.DefaultEngine {
en := engine.NewEngine(cfg, rs)
en = en.WithPersister(pr)
return en
}