Adding filter and refactoring functions for new import graph

cmd/api/handlers.go

@@ -45,7 +45,7 @@ func (app *application) createMovieHandler(w http.ResponseWriter, r *http.Reques
 
 	v := validator.New()
 
-	if validator.ValidateMovie(v, m); !v.Valid() {
+	if data.ValidateMovie(v, m); !v.Valid() {
 		app.failedValidationResponse(w, r, v.Errors)
 	}
 
@@ -177,7 +177,7 @@ func (app *application) updateMovieHandler(w http.ResponseWriter, r *http.Reques
 
 	v := validator.New()
 
-	if validator.ValidateMovie(v, movie); !v.Valid() {
+	if data.ValidateMovie(v, movie); !v.Valid() {
 		app.failedValidationResponse(w, r, v.Errors)
 		return
 	}
@@ -248,6 +248,28 @@ func (app *application) listMoviesHandler(w http.ResponseWriter, r *http.Request
 		app.logger.Debug("query params", "qp", qparams)
 	}
 
+	//holds values from input string
+	var input struct {
+		Title  string
+		Genres []string
+		data.Filters
+	}
+
+	v := validator.New()
+	input.Title = app.readString(qparams, "title", "")
+	input.Genres = app.readCSV(qparams, "genres", []string{})
+	input.Page = app.readInt(qparams, "page", 1, v)
+	input.PageSize = app.readInt(qparams, "page_size", 20, v)
+	input.Sort = app.readString(qparams, "sort", "id")
+	input.Filters.SortSafelist = []string{"id", "title", "year", "runtime", "-id", "-title", "-year", "-runtime"}
+
+	data.ValidateFilters(v, input.Filters)
+
+	if !v.Valid() {
+		app.failedValidationResponse(w, r, v.Errors)
+		return
+	}
+
 	movies, err := app.models.Movies.List(r.Context())
 	if err != nil {
 		app.serverErrorResponse(w, r, err)

cmd/api/helpers.go

@@ -10,9 +10,11 @@ import (
 	"fmt"
 	"io"
 	"net/http"
+	"net/url"
 	"strconv"
 	"strings"
 
+	"git.runcible.io/learning/pulley/internal/validator"
 	"github.com/julienschmidt/httprouter"
 )
 
@@ -156,3 +158,35 @@ func (a *application) readIDParam(r *http.Request) (int64, error) {
 
 	return id, err
 }
+
+func (a *application) readString(qs url.Values, key string, defaultValue string) string {
+	s := qs.Get(key)
+	if s == "" {
+		return defaultValue
+	}
+	return s
+}
+
+func (a *application) readInt(qs url.Values, key string, defaultInt int, v *validator.Validator) int {
+	s := qs.Get(key)
+	if s == "" {
+		return defaultInt
+	}
+
+	i, err := strconv.Atoi(s)
+	if err != nil {
+		v.AddError(key, "must be an integer value")
+		return defaultInt
+	}
+	return i
+
+}
+
+func (a *application) readCSV(qs url.Values, key string, defaultValue []string) []string {
+	s := qs.Get(key)
+	if s == "" {
+		return defaultValue
+	}
+
+	return strings.Split(s, ",")
+}

internal/data/filters.go

@@ -0,0 +1,18 @@
+package data
+
+import "git.runcible.io/learning/pulley/internal/validator"
+
+type Filters struct {
+	Page         int
+	PageSize     int
+	Sort         string
+	SortSafelist []string
+}
+
+func ValidateFilters(v *validator.Validator, f Filters) {
+	v.Check(f.Page > 0, "page", "must be greater than zero")
+	v.Check(f.Page < 10_000_000, "page", "must be a maximum of 10 million")
+	v.Check(f.PageSize > 0, "page_size", "must be greater than zero")
+	v.Check(f.PageSize <= 100, "page_size", "must be a maximum of 100")
+	v.Check(validator.PermittedValue(f.Sort, f.SortSafelist...), "sort", "invalid sort value")
+}

internal/data/movies.go

@@ -5,6 +5,7 @@ import (
 	"errors"
 	"time"
 
+	"git.runcible.io/learning/pulley/internal/validator"
 	"github.com/jackc/pgx/v5"
 	"github.com/jackc/pgx/v5/pgconn"
 	"github.com/jackc/pgx/v5/pgxpool"
@@ -52,8 +53,6 @@ func (m MovieModel) Get(ctx context.Context, id int64) (*Movie, error) {
 		return nil, ErrRecordNotFound
 	}
 
-	panic("OMG!")
-
 	query := `
 		SELECT id, created_at, title, year, runtime, genres, version
 		FROM movies
@@ -207,3 +206,18 @@ func (m MovieModel) List(ctx context.Context) ([]*Movie, error) {
 
 	return movies, nil
 }
+
+func ValidateMovie(v *validator.Validator, m *Movie) {
+
+	v.Check(m.Title != "", "title", "must be provided")
+	v.Check(len(m.Title) <= 500, "title", "must not be more than 500 bytes long")
+	v.Check(m.Year != 0, "year", "must be provided")
+	v.Check(m.Year >= 1888, "year", "must be greater than 1888")
+	v.Check(m.Year <= int32(time.Now().Year()), "year", "must not be in the future")
+	v.Check(m.Runtime != 0, "runtime", "must be provided")
+	v.Check(m.Runtime > 0, "runtime", "must be a positive integer")
+	v.Check(m.Genres != nil, "genres", "must be provided")
+	v.Check(len(m.Genres) >= 1, "genres", "must contain one genre")
+	v.Check(len(m.Genres) <= 5, "genres", "must not contain more than 5 genres")
+	v.Check(validator.Unique(m.Genres), "genres", "must not contain duplicate values")
+}

internal/validator/validator.go

@@ -1,10 +1,8 @@
 package validator
 
 import (
-	"git.runcible.io/learning/pulley/internal/data"
 	"regexp"
 	"slices"
-	"time"
 )
 
 // Declare a regular expression for sanity checking the format of email addresses (we'll
@@ -63,18 +61,3 @@ func Unique[T comparable](values []T) bool {
 
 	return len(values) == len(uniqueValues)
 }
-
-func ValidateMovie(v *Validator, m *data.Movie) {
-
-	v.Check(m.Title != "", "title", "must be provided")
-	v.Check(len(m.Title) <= 500, "title", "must not be more than 500 bytes long")
-	v.Check(m.Year != 0, "year", "must be provided")
-	v.Check(m.Year >= 1888, "year", "must be greater than 1888")
-	v.Check(m.Year <= int32(time.Now().Year()), "year", "must not be in the future")
-	v.Check(m.Runtime != 0, "runtime", "must be provided")
-	v.Check(m.Runtime > 0, "runtime", "must be a positive integer")
-	v.Check(m.Genres != nil, "genres", "must be provided")
-	v.Check(len(m.Genres) >= 1, "genres", "must contain one genre")
-	v.Check(len(m.Genres) <= 5, "genres", "must not contain more than 5 genres")
-	v.Check(Unique(m.Genres), "genres", "must not contain duplicate values")
-}