Reorganize types

cmd/api/errors.go

@@ -3,6 +3,8 @@ package main
 import (
 	"fmt"
 	"net/http"
+
+	"git.runcible.io/learning/pulley/internal/data"
 )
 
 // The logError() method is a generic helper for logging an error message along
@@ -20,8 +22,7 @@ func (app *application) logError(r *http.Request, err error) {
 // type for the message parameter, rather than just a string type, as this gives us
 // more flexibility over the values that we can include in the response.
 func (app *application) errorResponse(w http.ResponseWriter, r *http.Request, status int, message any) {
-	env := envelope{"error": message}
-
+	env := data.ErrorMessageResponse{ErrorMessage: message}
 	err := app.writeJSON(w, status, env, nil)
 	if err != nil {
 		app.logError(r, err)

cmd/api/handlers.go

@@ -36,7 +36,7 @@ func (app *application) createMovieHandler(w http.ResponseWriter, r *http.Reques
 	}
 
 	// use intermediate struct for decoding, use Movie struct for validation
-	m := &data.Movie{
+	movie := &data.Movie{
 		Title:   input.Title,
 		Year:    input.Year,
 		Runtime: input.Runtime,
@@ -45,24 +45,24 @@ func (app *application) createMovieHandler(w http.ResponseWriter, r *http.Reques
 
 	v := validator.New()
 
-	if data.ValidateMovie(v, m); !v.Valid() {
+	if data.ValidateMovie(v, movie); !v.Valid() {
 		app.failedValidationResponse(w, r, v.Errors)
 	}
 
 	// We can implement a timeout context if we would like here
 	ctx := r.Context()
 
-	err = app.models.Movies.Insert(ctx, m)
+	err = app.models.Movies.Insert(ctx, movie)
 	if err != nil {
 		app.serverErrorResponse(w, r, err)
 	}
 
 	// Include location headers in HTTP response for newly created resource
 	headers := make(http.Header)
-	headers.Set("Location", fmt.Sprintf("/v1/movies/%d", m.ID))
+	headers.Set("Location", fmt.Sprintf("/v1/movies/%d", movie.ID))
 
 	// Write a JSON 201 Response with movie data in the response body and Location header
-	err = app.writeJSON(w, http.StatusCreated, envelope{"movie": m}, headers)
+	err = app.writeJSON(w, http.StatusCreated, data.MovieResponse{Movie: movie}, headers)
 	if err != nil {
 		app.serverErrorResponse(w, r, err)
 	}
@@ -112,7 +112,7 @@ func (app *application) getMovieHandler(w http.ResponseWriter, r *http.Request)
 		}
 	}
 
-	err = app.writeJSON(w, http.StatusOK, envelope{"movie": movie}, nil)
+	err = app.writeJSON(w, http.StatusOK, data.MovieResponse{Movie: movie}, nil)
 	if err != nil {
 		//http.Error(w, "The server encountered a problem and could not process your request", http.StatusInternalServerError)
 		app.serverErrorResponse(w, r, err)
@@ -192,7 +192,7 @@ func (app *application) updateMovieHandler(w http.ResponseWriter, r *http.Reques
 		return
 	}
 
-	err = app.writeJSON(w, http.StatusOK, envelope{"movie": movie}, nil)
+	err = app.writeJSON(w, http.StatusOK, data.MovieResponse{Movie: movie}, nil)
 	if err != nil {
 		app.serverErrorResponse(w, r, err)
 	}
@@ -235,7 +235,7 @@ func (app *application) deleteMovieHandler(w http.ResponseWriter, r *http.Reques
 	// are machines then status code is alright.
 	//w.WriteHeader(http.StatusAccepted)
 
-	err = app.writeJSON(w, http.StatusOK, envelope{"message": "movie successfully deleted"}, nil)
+	err = app.writeJSON(w, http.StatusOK, data.GenericMessageResponse{Message: "movie successfully deleted"}, nil)
 	if err != nil {
 		app.serverErrorResponse(w, r, err)
 	}
@@ -274,7 +274,9 @@ func (app *application) listMoviesHandler(w http.ResponseWriter, r *http.Request
 		app.serverErrorResponse(w, r, err)
 		return
 	}
-	app.writeJSON(w, 200, envelope{"movies": movies, "metadata": metadata}, nil)
+
+	// app.writeJSON(w, 200, envelope{"movies": movies, "metadata": metadata}, nil)
+	app.writeJSON(w, 200, data.ListMoviesResponse{Metadata: metadata, Movies: movies}, nil)
 }
 
 func (app *application) healthCheckHandler(w http.ResponseWriter, r *http.Request) {
@@ -282,13 +284,13 @@ func (app *application) healthCheckHandler(w http.ResponseWriter, r *http.Reques
 	// js := `{"status": "available", "environment": %q, "version": %q}`
 	// js = fmt.Sprintf(js, app.config.env, Version)
 	// w.Write([]byte(js))
-	env := envelope{
-		"status": "available",
-		"system_info": map[string]string{
-			"environment": app.config.Env,
-			"version":     Version,
-		},
-	}
+	// env := envelope{
+	// 	"status": "available",
+	// 	"system_info": map[string]string{
+	// 		"environment": app.config.Env,
+	// 		"version":     Version,
+	// 	},
+	// }
 
 	// js, err := json.Marshal(data)
 	// if err != nil {
@@ -301,7 +303,7 @@ func (app *application) healthCheckHandler(w http.ResponseWriter, r *http.Reques
 	// js = append(js, '\n')
 	// w.Header().Set("Content-Type", "application/json")
 	// w.Write(js)
-	err := app.writeJSON(w, 200, env, nil)
+	err := app.writeJSON(w, 200, data.HealthCheckResponse{Status: "available", SystemInfo: data.SystemInfo{Environment: app.config.Env, Version: Version}}, nil)
 	if err != nil {
 		//app.logger.Error(err.Error())
 		//http.Error(w, "The server encountered a problem and could not process your request", http.StatusInternalServerError)

cmd/api/handlers_integration_test.go

@@ -45,13 +45,20 @@ func TestHttpListHandlers(t *testing.T) {
 		defer resp.Body.Close()
 		body, err := io.ReadAll(resp.Body)
 		assert.NilError(t, err)
-
-		content := make(map[string][]data.Movie)
+		/// If you use an anonymous struct be sure to use exported fields
+		// the encoding/json package can only work with exported fields
+		// content := new(struct {
+		// 	Metadata data.Metadata
+		// 	Movies   []data.Movie
+		// })
+		content := new(data.ListMoviesResponse)
 		err = json.Unmarshal(body, &content)
 		assert.NilError(t, err)
-
-		assert.Equal(t, len(content["movies"]), 1)
-		assert.MovieEqual(t, content["movies"][0], movies[0])
+		t.Logf("Values: %v", content)
+		assert.Equal(t, len(content.Movies), 1)
+		assert.MovieEqual(t, *content.Movies[0], movies[0])
+		assert.Equal(t, content.Metadata.CurrentPage, 1)
+		assert.Equal(t, content.Metadata.TotalRecords, 1)
 	})
 
 }

cmd/api/handlers_test.go

@@ -344,14 +344,15 @@ func TestListMovieHandler(t *testing.T) {
 	defer resp.Body.Close()
 	body, err := io.ReadAll(resp.Body)
 	assert.NilError(t, err)
-	jsonContent := make(map[string][]data.Movie)
+	// jsonContent := make(map[string][]data.Movie)
+	jsonContent := new(data.ListMoviesResponse)
 
 	err = json.Unmarshal(body, &jsonContent)
 	assert.NilError(t, err)
 
-	assert.Equal(t, len(jsonContent["movies"]), 2)
-	for i := range jsonContent["movies"] {
-		assert.MovieEqual(t, jsonContent["movies"][i], movies[i])
+	assert.Equal(t, len(jsonContent.Movies), 2)
+	for i := range jsonContent.Movies {
+		assert.MovieEqual(t, *jsonContent.Movies[i], movies[i])
 	}
 
 	err = mockPool.ExpectationsWereMet()

cmd/api/helpers.go

@@ -18,7 +18,9 @@ import (
 	"github.com/julienschmidt/httprouter"
 )
 
-type envelope map[string]any
+// We moved from a generic map envelope to specific types in internal/dto.go
+// type envelope map[string]any
+type envelope any
 
 // This was the original function signature without enveloping
 // func (app *application) writeJSON(w http.ResponseWriter, status int, data any, headers http.Header) error {

internal/data/dto.go

@@ -0,0 +1,28 @@
+package data
+
+type ListMoviesResponse struct {
+	Metadata Metadata `json:"metadata"`
+	Movies   []*Movie `json:"movies"`
+}
+
+type MovieResponse struct {
+	Movie *Movie `json:"movie"`
+}
+
+type SystemInfo struct {
+	Environment string `json:"environment"`
+	Version     string `json:"version"`
+}
+
+type HealthCheckResponse struct {
+	Status     string     `json:"status"`
+	SystemInfo SystemInfo `json:"system_info"`
+}
+
+type GenericMessageResponse struct {
+	Message string `json:"message"`
+}
+
+type ErrorMessageResponse struct {
+	ErrorMessage any `json:"error"`
+}