Merge pull request #5 from jesusangelm/pagination_and_some_improvements

add basic pagination

cmd/web/categories_handler.go

@@ -0,0 +1,92 @@
+package main
+
+import (
+	"errors"
+	"net/http"
+	"strconv"
+
+	"github.com/julienschmidt/httprouter"
+	"jesusmarin.dev/galeria/internal/data"
+	"jesusmarin.dev/galeria/internal/validator"
+)
+
+// home handler for root route
+func (app *application) listCategories(w http.ResponseWriter, r *http.Request) {
+	var input struct {
+		Name string
+		data.Filters
+	}
+
+	v := validator.New()
+	qs := r.URL.Query() // To get filter parameters from the QueryString
+
+	input.Name = app.readString(qs, "name", "")
+	input.Filters.Page = app.readInt(qs, "page", 1, v)
+	input.Filters.PageSize = app.readInt(qs, "page_size", 6, v)
+	input.Filters.Sort = app.readString(qs, "sort", "-created_at")
+	input.Filters.SortSafeList = []string{
+		"id", "name", "created_at", "-id", "-name", "-created_at",
+	}
+
+	if data.ValidateFilters(v, input.Filters); !v.Valid() {
+		app.notFound(w)
+		return
+	}
+
+	categories, metadata, err := app.models.Categories.List(input.Name, input.Filters)
+	if err != nil {
+		app.serverError(w, err)
+	}
+
+	templatedata := app.newTemplateData(r)
+	templatedata.Categories = categories
+	templatedata.Metadata = metadata
+
+	app.render(w, http.StatusOK, "home.tmpl", templatedata)
+}
+
+func (app *application) categoryShow(w http.ResponseWriter, r *http.Request) {
+	var input struct {
+		Name string
+		data.Filters
+	}
+
+	v := validator.New()
+	qs := r.URL.Query() // To get filter parameters from the QueryString
+
+	input.Filters.Page = app.readInt(qs, "page", 1, v)
+	input.Filters.PageSize = app.readInt(qs, "page_size", 6, v)
+	input.Filters.Sort = app.readString(qs, "sort", "-created_at")
+	input.Filters.SortSafeList = []string{
+		"id", "name", "created_at", "-id", "-name", "-created_at",
+	}
+
+	if data.ValidateFilters(v, input.Filters); !v.Valid() {
+		app.notFound(w)
+		return
+	}
+
+	params := httprouter.ParamsFromContext(r.Context())
+
+	id, err := strconv.Atoi(params.ByName("id"))
+	if err != nil || id < 1 {
+		app.notFound(w)
+		return
+	}
+
+	category, metadata, err := app.models.Categories.Get(int64(id), input.Filters)
+	if err != nil {
+		if errors.Is(err, data.ErrRecordNotFound) {
+			app.notFound(w)
+		} else {
+			app.serverError(w, err)
+		}
+		return
+	}
+
+	data := app.newTemplateData(r)
+	data.Category = category
+	data.Metadata = metadata
+
+	app.render(w, http.StatusOK, "category_view.tmpl", data)
+}

cmd/web/helpers.go

@@ -4,8 +4,13 @@ import (
 	"bytes"
 	"fmt"
 	"net/http"
+	"net/url"
 	"runtime/debug"
+	"strconv"
+	"strings"
 	"time"
+
+	"jesusmarin.dev/galeria/internal/validator"
 )
 
 // Helper that write an error message and stack trace to the errorLog.
@@ -63,3 +68,39 @@ func (app *application) render(w http.ResponseWriter, status int, page string, d
 
 	buf.WriteTo(w)
 }
+
+func (app *application) readString(qs url.Values, key string, defaultValue string) string {
+	s := qs.Get(key)
+
+	if s == "" {
+		return defaultValue
+	}
+
+	return s
+}
+
+func (app *application) readCSV(qs url.Values, key string, defaultValue []string) []string {
+	csv := qs.Get(key)
+
+	if csv == "" {
+		return defaultValue
+	}
+
+	return strings.Split(csv, ",")
+}
+
+func (app *application) readInt(qs url.Values, key string, defaultValue int, v *validator.Validator) int {
+	s := qs.Get(key)
+
+	if s == "" {
+		return defaultValue
+	}
+
+	i, err := strconv.Atoi(s)
+	if err != nil {
+		v.AddError(key, "must be an integer value")
+		return defaultValue
+	}
+
+	return i
+}

cmd/web/images_handler.go

@@ -0,0 +1,42 @@
+package main
+
+import (
+	"io"
+	"log"
+	"net/http"
+
+	"github.com/julienschmidt/httprouter"
+)
+
+func (app *application) images(w http.ResponseWriter, r *http.Request) {
+	params := httprouter.ParamsFromContext(r.Context())
+
+	key := params.ByName("key")
+	if key == "" {
+		app.notFound(w)
+		return
+	}
+
+	imageUrl := app.s3Manager.GetFileUrl(key)
+
+	resp, err := http.Get(imageUrl)
+	if err != nil {
+		log.Fatal(err)
+	}
+	defer resp.Body.Close()
+
+	if resp.StatusCode != http.StatusOK {
+		app.notFound(w)
+		return
+	}
+
+	contentType := resp.Header.Get("Content-Type")
+
+	w.Header().Set("Content-Type", contentType)
+	w.Header().Set("Cache-Control", "max-age=3155695200, public")
+	_, err = io.Copy(w, resp.Body)
+	if err != nil {
+		log.Fatal(err)
+		app.serverError(w, err)
+	}
+}

cmd/web/items_handler.go

@@ -0,0 +1,35 @@
+package main
+
+import (
+	"errors"
+	"net/http"
+	"strconv"
+
+	"github.com/julienschmidt/httprouter"
+	"jesusmarin.dev/galeria/internal/data"
+)
+
+func (app *application) itemShow(w http.ResponseWriter, r *http.Request) {
+	params := httprouter.ParamsFromContext(r.Context())
+
+	id, err := strconv.Atoi(params.ByName("id"))
+	if err != nil || id < 1 {
+		app.notFound(w)
+		return
+	}
+
+	item, err := app.models.Items.Get(int64(id))
+	if err != nil {
+		if errors.Is(err, data.ErrRecordNotFound) {
+			app.notFound(w)
+		} else {
+			app.serverError(w, err)
+		}
+		return
+	}
+
+	data := app.newTemplateData(r)
+	data.Item = item
+
+	app.render(w, http.StatusOK, "item_view.tmpl", data)
+}

cmd/web/routes.go

@@ -20,7 +20,7 @@ func (app *application) routes() http.Handler {
 	router.HandlerFunc(http.MethodGet, "/images/:key", app.images)
 
 	// Routes definition
-	router.HandlerFunc(http.MethodGet, "/", app.home)
+	router.HandlerFunc(http.MethodGet, "/", app.listCategories)
 	router.HandlerFunc(http.MethodGet, "/category/:id", app.categoryShow)
 	router.HandlerFunc(http.MethodGet, "/item/:id", app.itemShow)
 

cmd/web/templates.go

@@ -18,6 +18,7 @@ type templateData struct {
 	Categories  []*data.Category
 	Item        *data.Item
 	Items       []*data.Item
+	Metadata    data.Metadata
 }
 
 // Create a humanDate function which returns a nicely formatted string
@@ -26,11 +27,21 @@ func humanDate(t time.Time) string {
 	return t.Format("02 jan 2006 at 15:04")
 }
 
+func add(a, b int) int {
+	return a + b
+}
+
+func sust(a, b int) int {
+	return a - b
+}
+
 // Initialize a template.FuncMap object and store it in a global variable. This is
 // essentially a string-keyed map which acts as a lookup between the names of our
 // custom template functions and the functions themselves.
 var functions = template.FuncMap{
 	"humanDate": humanDate,
+	"add":       add,
+	"sust":      sust,
 }
 
 // function for read and copy all .tmpl templates in a map variable stored in memory.