huge refactoring

app/handlers/context/context.go

@@ -0,0 +1,51 @@
+package context
+
+import (
+	"context"
+	"net/http"
+
+	"github.com/gulien/gotenberg/app/handlers/converter"
+
+	ghttp "github.com/gulien/gotenberg/app/handlers/http"
+)
+
+type key uint32
+
+const (
+	contentTypeKey key = iota
+	converterKey
+)
+
+func WithContentType(r *http.Request, contentType ghttp.ContentType) *http.Request {
+	ctx := r.Context()
+	ctx = context.WithValue(ctx, contentTypeKey, contentType)
+	r = r.WithContext(ctx)
+
+	return r
+}
+
+func GetContentType(r *http.Request) (ghttp.ContentType, error) {
+	ct, ok := r.Context().Value(contentTypeKey).(ghttp.ContentType)
+	if !ok {
+		return "", &contentTypeNotFoundError{}
+	}
+
+	return ct, nil
+}
+
+func WithConverter(r *http.Request, converter *converter.Converter) *http.Request {
+	ctx := r.Context()
+	ctx = context.WithValue(ctx, converterKey, converter)
+	r = r.WithContext(ctx)
+
+	return r
+}
+
+func GetConverter(r *http.Request) (*converter.Converter, error) {
+	c, ok := r.Context().Value(converterKey).(*converter.Converter)
+	if !ok {
+		return nil, &converterNotFoundError{}
+	}
+
+	return c, nil
+}

app/handlers/context/errors.go

@@ -0,0 +1,13 @@
+package context
+
+type contentTypeNotFoundError struct{}
+
+func (e *contentTypeNotFoundError) Error() string {
+	return "The 'Content-Type' was not found in request context"
+}
+
+type converterNotFoundError struct{}
+
+func (e *converterNotFoundError) Error() string {
+	return "The converter was not found in request context"
+}