refactor(errors): new error "helpers", following a more golang way

internals/router/errors/400.go

@@ -0,0 +1,20 @@
+package errors
+
+import (
+	"fmt"
+	"net/http"
+	"strings"
+)
+
+type ErrMissingParams struct {
+	defaultErr
+	Params []string `json:"params"`
+}
+
+func NewErrMissingParams(params ...string) ErrMissingParams {
+	return ErrMissingParams{Params: params}
+}
+func (e ErrMissingParams) Error() string {
+	return fmt.Sprintf("Missing parameters: %s.", strings.Join(e.Params, ", "))
+}
+func (e ErrMissingParams) Status() int { return http.StatusBadRequest }

internals/router/errors/500.go

@@ -0,0 +1,15 @@
+package errors
+
+import (
+	"errors"
+	"net/http"
+)
+
+type ErrInternal struct {
+	defaultErr
+	Err string `json:"error"`
+}
+
+func NewErrInternal(err ...error) ErrInternal { return ErrInternal{Err: errors.Join(err...).Error()} }
+func (e ErrInternal) Error() string           { return e.Err }
+func (e ErrInternal) Status() int             { return http.StatusInternalServerError }

internals/router/errors/errors.templ

@@ -0,0 +1,90 @@
+package errors
+
+import (
+	"net/http"
+	"strings"
+	"extrovert/templates/layouts"
+	"encoding/json"
+)
+
+type Error interface {
+	Error() string
+	Status() int
+	ServeHTTP(w http.ResponseWriter, r *http.Request)
+	Component() templ.Component
+	JSON() string
+}
+
+type defaultErr struct{}
+
+func (e defaultErr) Error() string {
+	return "Error: This method should have been overridden :')"
+}
+
+func (e defaultErr) Status() int {
+	return http.StatusNotImplemented
+}
+
+func (e defaultErr) ServeHTTP(w http.ResponseWriter, r *http.Request) {
+	if strings.Contains(r.Header.Get("Accept"), "text/html") {
+		w.Header().Set("Content-Type", "text/html")
+
+		err := e.Component().Render(r.Context(), w)
+		if err != nil {
+			w.Header().Set("Content-Type", "text/plain")
+			w.Write([]byte("Unable to render error message, using JSON representation: " + e.JSON()))
+			w.WriteHeader(http.StatusInternalServerError)
+			return
+		}
+	} else {
+		w.Header().Set("Content-Type", "application/json")
+
+		_, err := w.Write([]byte(e.JSON()))
+		if err != nil {
+			w.Header().Set("Content-Type", "text/plain")
+			w.Write([]byte("Unable to send error information due to: " + err.Error()))
+			w.WriteHeader(http.StatusInternalServerError)
+			return
+		}
+	}
+	w.WriteHeader(e.Status())
+}
+
+func (e defaultErr) JSON() string {
+	type jsonErr struct {
+		Error string `json:"error"`
+		Info  any    `json:"info"`
+	}
+	js, err := json.Marshal(jsonErr{
+		Error: e.Error(),
+		Info:  e,
+	})
+	if err != nil {
+		js, _ = json.Marshal(jsonErr{
+			Error: "Unable to parse JSON of error",
+			Info:  err.Error(),
+		})
+	}
+
+	return string(js)
+}
+
+templ (e defaultErr) Component() {
+	@layouts.Page("Error") {
+		<dialog open>
+			<article>
+				<header>
+					<p>Error</p>
+				</header>
+				<p>
+					{ e.Error() }
+				</p>
+				<footer>
+					<a href={ templ.SafeURL("/") }>
+						<button>Return to homepage</button>
+					</a>
+				</footer>
+			</article>
+		</dialog>
+	}
+}

routes/index.templ

@@ -4,13 +4,18 @@ import (
 	"extrovert/templates/layouts"
 	"extrovert/components"
 	"net/http"
+	"extrovert/internals/router/errors"
+	e "errors"
 )
 
 type Homepage struct{}
 
 func (h Homepage) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 	w.WriteHeader(http.StatusOK)
-	_ = h.page().Render(context.Background(), w)
+	err := h.page().Render(context.Background(), w)
+	if err != nil {
+		errors.NewErrInternal(e.New("Unable to render dashboard"), err).ServeHTTP(w, r)
+	}
 }
 
 templ (h Homepage) page() {

routes/robots.go

@@ -1,10 +1,11 @@
 package routes
 
 import (
+	e "errors"
 	"io"
 	"net/http"
 
-	"extrovert/internals"
+	"extrovert/internals/router/errors"
 )
 
 type AITxt struct{}
@@ -13,23 +14,24 @@ func (_ AITxt) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 	w.Header().Add("Cache-Control", "max-age=604800, stale-while-revalidate=86400, stale-if-error=86400")
 	w.Header().Add("CDN-Cache-Control", "max-age=604800")
 
-	error := internals.HttpErrorHelper(w)
-
-	aiList, err := http.Get("https://raw.githubusercontent.com/ai-robots-txt/ai.robots.txt/main/ai.txt")
-	if error("Error trying to create ai block list", err, http.StatusInternalServerError) {
+	list, err := http.Get("https://raw.githubusercontent.com/ai-robots-txt/ai.robots.txt/main/ai.txt")
+	if err != nil {
+		errors.NewErrInternal(e.New("Unable to fetch ai.txt list"), err).ServeHTTP(w, r)
 		return
 	}
 
-	bytes, err := io.ReadAll(aiList.Body)
-	if error("Error trying to create ai block list", err, http.StatusInternalServerError) {
-		return
-	}
-	_, err = io.WriteString(w, string(bytes))
-	if error("Error trying to create ai block list", err, http.StatusInternalServerError) {
+	bytes, err := io.ReadAll(list.Body)
+	if err != nil {
+		errors.NewErrInternal(e.New("Unable to read dynamic ai.txt list"), err).ServeHTTP(w, r)
 		return
 	}
 
 	w.Header().Add("Content-Type", "text/plain")
+	_, err = w.Write(bytes)
+	if err != nil {
+		errors.NewErrInternal(e.New("Unable to write ai.txt list"), err).ServeHTTP(w, r)
+		return
+	}
 }
 
 type RobotsTxt struct{}
@@ -38,19 +40,21 @@ func (_ RobotsTxt) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 	w.Header().Add("Cache-Control", "max-age=604800, stale-while-revalidate=86400, stale-if-error=86400")
 	w.Header().Add("CDN-Cache-Control", "max-age=604800")
 
-	error := internals.HttpErrorHelper(w)
-	aiList, err := http.Get("https://raw.githubusercontent.com/ai-robots-txt/ai.robots.txt/main/robots.txt")
-	if error("Error trying to create robots block list", err, http.StatusInternalServerError) {
+	list, err := http.Get("https://raw.githubusercontent.com/ai-robots-txt/ai.robots.txt/main/robots.txt")
+	if err != nil {
+		errors.NewErrInternal(e.New("Unable to fetch robots.txt list"), err).ServeHTTP(w, r)
 		return
 	}
 
-	bytes, err := io.ReadAll(aiList.Body)
-	if error("Error trying to create robots block list", err, http.StatusInternalServerError) {
+	bytes, err := io.ReadAll(list.Body)
+	if err != nil {
+		errors.NewErrInternal(e.New("Unable to read dynamic robots.txt list"), err).ServeHTTP(w, r)
 		return
 	}
 
 	_, err = io.WriteString(w, string(bytes))
-	if error("Error trying to create robots block list", err, http.StatusInternalServerError) {
+	if err != nil {
+		errors.NewErrInternal(e.New("Unable to write robots.txt list"), err).ServeHTTP(w, r)
 		return
 	}
 	w.Header().Add("Content-Type", "text/plain")