Implemented map functions + caching@

command_exit.go

@@ -3,9 +3,10 @@ package main
 import (
 	"fmt"
 	"os"
+	"k3gtpi.jumpingcrab.com/go-learning/pokedexcli/internal/pokecache"
 )
 
-func commandExit() error {
+func commandExit(p *PokedexConfig, c *pokecache.Cache) error {
 	fmt.Println("Closing the Pokedex... Goodbye!")
 	os.Exit(0)
 	return nil

command_help.go

@@ -2,10 +2,11 @@ package main
 
 import (
 	"fmt"
+	"k3gtpi.jumpingcrab.com/go-learning/pokedexcli/internal/pokecache"
 )
 
 
-func commandHelp() error {
+func commandHelp(p *PokedexConfig, c *pokecache.Cache) error {
 	fmt.Print("Pokedex CLI - available commands:\n\n")
 	for _, v := range getCommands() {
 		fmt.Printf("%s		%s\n", v.name, v.description)

command_map.go

@@ -1,5 +1,50 @@
 package main
 
-func commandMap() error {
+import (
+	"fmt"
+	"net/http"
+	"encoding/json"
+	"io"
+	"k3gtpi.jumpingcrab.com/go-learning/pokedexcli/internal/pokecache"
+)
+
+
+func commandMap(p *PokedexConfig, c *pokecache.Cache) error {
+	var baseUrl string
+	if p.Next == nil {
+		baseUrl = "https://pokeapi.co/api/v2/location-area/"
+	} else {
+		baseUrl = *p.Next
+	}
+
+	var body []byte
+	// Check if respones is available in cache
+	if resp, exists := c.Get(baseUrl); exists {
+		body = resp
+	} else {
+		client := &http.Client{}
+
+		resp, err := client.Get(baseUrl)
+		if err != nil {
+			return fmt.Errorf("could not make request to Pokedex API! Err: %w", err)
+		}
+
+		body, err = io.ReadAll(resp.Body)	
+		defer resp.Body.Close()
+		if resp.StatusCode > 299 {
+			return fmt.Errorf("request returned non-200 code! Code: %v Body: %v", resp.StatusCode, body)
+		}
+		if err != nil {
+			return fmt.Errorf("could not read request body! Err: %w", err)
+		}
+		c.Add(baseUrl, body)
+	}
+
+	if err := json.Unmarshal(body, &p); err != nil {
+		return fmt.Errorf("could not unmarshal response! Err: %w", err)
+	}
+	for _, location := range p.Results {
+		fmt.Println(location["name"])
+	}
 	return nil
 }

command_mapb.go

@@ -0,0 +1,48 @@
+package main
+
+import (
+	"fmt"
+	"io"
+	"encoding/json"
+	"net/http"
+	"k3gtpi.jumpingcrab.com/go-learning/pokedexcli/internal/pokecache"
+)
+
+func commandMapb(p *PokedexConfig, c *pokecache.Cache) error {
+	var baseUrl string
+	if p.Previous == nil {
+		fmt.Println("you're on the first page")
+		return nil
+	} else {
+		baseUrl = *p.Previous
+	}
+	var body []byte
+	if resp, exists := c.Get(baseUrl); exists {
+		body = resp
+	} else {
+		client := &http.Client{}
+		
+		resp, err := client.Get(baseUrl)
+		if err != nil {
+			return fmt.Errorf("could not make request to Pokedex API! Err: %w", err)
+		}
+		
+		body, err = io.ReadAll(resp.Body)	
+		defer resp.Body.Close()
+		if resp.StatusCode > 299 {
+			return fmt.Errorf("request returned non-200 code! Code: %v Body: %v", resp.StatusCode, body)
+		}
+		if err != nil {
+			return fmt.Errorf("could not read request body! Err: %w", err)
+		}
+
+		c.Add(baseUrl, body)
+	}
+	if err := json.Unmarshal(body, &p); err != nil {
+		return fmt.Errorf("could not unmarshal response! Err: %w", err)
+	}
+	for _, location := range p.Results {
+		fmt.Println(location["name"])
+	}
+	return nil
+}

internal/pokecache/pokecache.go

@@ -0,0 +1,65 @@
+package pokecache
+
+import (
+	"time"
+	"sync"
+)
+
+type cacheEntry struct {
+	createdAt	time.Time
+	val			[]byte
+}
+
+type Cache struct {
+	PokeCache	map[string]cacheEntry
+	Interval	time.Duration
+	Mu			sync.Mutex
+}
+
+func (c *Cache) Add(key string, val []byte) {
+	newEntry := cacheEntry{
+		createdAt: 	time.Now(),
+		val:		val,
+	}
+	c.Mu.Lock()
+	defer c.Mu.Unlock()
+	c.PokeCache[key] = newEntry
+}
+
+func (c *Cache) Get(key string) ([]byte, bool) {
+	c.Mu.Lock()
+
+	defer c.Mu.Unlock()
+	cache, exists := c.PokeCache[key]
+	if !exists {
+		return nil, false
+	}
+	return cache.val, true
+}
+
+func (c *Cache) reapLoop() {
+	ticker := time.NewTicker(c.Interval)
+	defer ticker.Stop()
+
+	for range ticker.C {
+		c.Mu.Lock()
+		for k, v := range c.PokeCache {
+			if time.Since(v.createdAt) > c.Interval {
+				delete(c.PokeCache,  k)
+			}
+		}
+		c.Mu.Unlock()
+	}
+}
+
+func NewCache(interval time.Duration) *Cache {
+	newCache := Cache{
+		PokeCache: map[string]cacheEntry{},
+		Interval: interval,
+		Mu: sync.Mutex{},
+	}
+	go newCache.reapLoop()
+	return &newCache
+}
+
+

internal/pokecache/pokecache_test.go

@@ -0,0 +1,71 @@
+package pokecache
+
+import (
+	"testing"
+	"time"
+	"fmt"
+)
+
+
+func TestAddGet(t *testing.T) {
+	const interval = 5 * time.Second
+	cases := []struct {
+		key string
+		val []byte
+	}{
+		{
+			key: "https://example.com",
+			val: []byte("testdata"),
+		},
+		{
+			key: "https://example.com/path",
+			val: []byte("moretestdata"),
+		},
+	}
+
+	for i, c := range cases {
+		t.Run(fmt.Sprintf("Test case %v", i), func(t *testing.T) {
+			cache := NewCache(interval)
+			cache.Add(c.key, c.val)
+			val, ok := cache.Get(c.key)
+			if !ok {
+				t.Errorf("expected to find key")
+				return
+			}
+			if string(val) != string(c.val) {
+				t.Errorf("expected to find value")
+				return
+			}
+		})
+	}
+}
+
+func TestGetNonexistent(t *testing.T) {
+	const interval = 2 * time.Second
+	cache := NewCache(interval)
+	value, ok := cache.Get("http://does.not.exist/")
+	if ok || (value != nil) {
+		t.Errorf("expected cache miss")
+	}
+}
+
+func TestReapLoop(t *testing.T) {
+	const baseTime = 5 * time.Millisecond
+	const waitTime = baseTime + 5*time.Millisecond
+	cache := NewCache(baseTime)
+	cache.Add("https://example.com", []byte("testdata"))
+	
+	_, ok := cache.Get("https://example.com")
+	if !ok {
+		t.Errorf("expected to find key")
+		return
+	}
+
+	time.Sleep(waitTime)
+
+	_, ok = cache.Get("https://example.com")
+	if ok {
+		t.Errorf("expected to not find key")
+		return
+	}
+}

repl.go

@@ -5,12 +5,20 @@ import (
 	"strings"
 	"bufio"
 	"os"
+	"k3gtpi.jumpingcrab.com/go-learning/pokedexcli/internal/pokecache"
+	"time"
 )
 
 type cliCommand struct {
 	name		string
 	description	string
-	callback	func() error
+	callback	func(*PokedexConfig, *pokecache.Cache) error
+}
+
+type PokedexConfig struct {
+	Next		*string
+	Previous	*string
+	Results		[]map[string]string
 }
 
 var supportedCommands map[string]cliCommand
@@ -18,6 +26,8 @@ var supportedCommands map[string]cliCommand
 func startRepl() {
 	reader := bufio.NewScanner(os.Stdin)
 	fmt.Println("Welcome to the Pokedex!")
+	pokedexConfig := PokedexConfig{}
+	cache := pokecache.NewCache(5 * time.Second)
 	for {
 		// Print prompt
 		fmt.Printf("Pokedex > ")
@@ -35,8 +45,8 @@ func startRepl() {
 			fmt.Println("Unknown command.")
 			continue
 		}
-		if err := command.callback(); err != nil {
-			fmt.Printf("Encountered error running command: %v\n", command.name)
+		if err := command.callback(&pokedexConfig, cache); err != nil {
+			fmt.Printf("Encountered error running command: %v\nErr: %v", command.name, err)
 		}
 	}
 }
@@ -68,5 +78,10 @@ func getCommands() map[string]cliCommand{
 			description:	"Print Pokemon world locations.",
 			callback:		commandMap,
 		},
+		"mapb": {
+			name:			"mapb",
+			description:	"Print previoud Pokemon locationsi.",
+			callback:		commandMapb,
+		},
 	}
 }