apigen/lib/processGoServerOutput.go

package lib

import (
	"bytes"
	_ "embed"
	"fmt"
	"os"
)

func processGoServerOutput(f string) error {
	buf := &bytes.Buffer{}
	//W := func(s string, p ...interface{}) {
	//	buf.WriteString(fmt.Sprintf(s, p...))
	//}
	WNL := func(s string, p ...interface{}) {
		buf.WriteString(fmt.Sprintf(s+"\n", p...))
	}

	ResImplType := func(v *APIParamType) string {
		ret := ""
		if !v.IsArray || v.Ispointer {
			ret = ret + "&"
		}
		ret += v.Typename + "{}"
		return ret
	}

	WNL("package %s", api.Namespace)
	WNL(`import (
			"context"
			"encoding/json"
			"strings"
			"net/http"
		)`)

	for k := range api.UsedImportsFunctions {
		WNL(`import "%s"`, k)
	}

	WNL(`type API struct {
	Mux   *http.ServeMux
	Perms map[string]string
}

func (a *API) GetPerm(r *http.Request) string {
	return a.Perms[r.Method+"_"+strings.Split(r.RequestURI, "?")[0]]
}
`)

	WNL(`func Init() *API{
	mux := &http.ServeMux{}
		
	ret := &API{
		Mux:   mux,
		Perms: make(map[string]string),
	}`)
	for _, v := range api.Methods {
		if v.Perm != "" {
			WNL(`	ret.Perms["%s_%s"]="%s"`, v.Verb, v.Path, v.Perm)
		}

	}
	for _, v := range api.SortedPaths {
		WNL(`	mux.HandleFunc("%s",func(w http.ResponseWriter, r *http.Request) {
		switch r.Method {`, v.Path)
		for _, v1 := range v.SortedVerbs {
			WNL(`		case "%s":`, v1.Method.Verb)
			if v1.Method.Raw {
				WNL(`		%s(w,r)`, v1.Method.Name)
			} else {
				WNL(`		h_%s(w,r)`, v1.Method.Name)
			}
		}

		WNL(`		default:
			http.Error(w,"Method not allowed",500)
		}`)

	}
	WNL(`	})`)

	WNL(`	return ret
}`)

	for _, v := range api.Methods {
		WNL(`func h_%s(w http.ResponseWriter, r *http.Request) {
	ctx := r.Context()
	ctx = context.WithValue(r.Context(), "REQ", r)
	ctx = context.WithValue(ctx, "RES", w)`, v.Name)

		WNL("	req := %s", ResImplType(v.ReqType))

		WNL(`	if r.Method!=http.MethodGet && r.Method!=http.MethodHead {`)

		if v.ReqType.Ispointer || v.ReqType.IsArray {
			WNL("	err := json.NewDecoder(r.Body).Decode(req)")
		} else {
			WNL("	err := json.NewDecoder(r.Body).Decode(&req)")
		}

		WNL(`	if err != nil {
				    http.Error(w, err.Error(), 500)
					return
				}
			}`)

		WNL(`	res, err := %s(ctx,req)`, v.Name)
		WNL(`	if err != nil {
		http.Error(w, err.Error(), 500)
		return
	}
	w.Header().Add("Content-Type","Application/json")
	err=json.NewEncoder(w).Encode(res)
	if err != nil {
		http.Error(w, err.Error(), 500)
		return
	}
}`)

	}

	return os.WriteFile(f, buf.Bytes(), 0600)
}