Some Structure

api/fetch/fetch.go

@@ -1,14 +0,0 @@
-package fetch
-
-import (
-	"net/http"
-)
-
-func Fetch(url string) (*http.Response, error) {
-	u, err := url.ParseRequestURI(url)
-	if err != nil {
-		return nil, err
-	}
-
-	return http.Get(url)
-}

api/server.go

@@ -1,78 +0,0 @@
-package main
-
-import (
-	"io"
-	"net/http"
-	"net/url"
-	"strings"
-
-	"golang.org/x/net/html"
-
-	"github.com/gin-gonic/gin"
-)
-
-func main() {
-	r := gin.Default()
-	r.GET("/bl/:bundesland", bundesland)
-	r.Run("localhost:8080")
-}
-
-func bundesland(c *gin.Context) {
-	bundesland := c.Param("bundesland")
-	if bundesland == "" {
-		c.JSON(http.StatusBadRequest, gin.H{
-			"error": "bundesland is required",
-		})
-		return
-	}
-	resp, err := Fetch("bl/" + bundesland)
-	if err != nil {
-		c.JSON(http.StatusInternalServerError, gin.H{
-			"error": err.Error(),
-		})
-		return
-	}
-	defer resp.Body.Close()
-	d, err := io.ReadAll(resp.Body)
-	if err != nil {
-		c.JSON(http.StatusInternalServerError, gin.H{
-			"error": err.Error(),
-		})
-		return
-	}
-	html := string(d)
-	scraped := ScrapeBundesland(html)
-	c.JSON(http.StatusOK, scraped)
-}
-
-func Fetch(path string) (*http.Response, error) {
-	baseurl := "https://www.imensa.de/"
-	queryurl := baseurl + "/" + path
-	u, err := url.ParseRequestURI(queryurl)
-	if err != nil {
-		return nil, err
-	}
-	return http.Get(u.String())
-}
-
-func ScrapeBundesland(h string) []string {
-	tkn := html.NewTokenizer(strings.NewReader(h))
-
-	var mensen []string
-
-	for {
-		if tkn.Next() == html.ErrorToken {
-			return mensen
-		}
-
-		t := tkn.Token()
-		attr := t.Attr
-
-		for _, a := range attr {
-			if a.Key == "class" && a.Val == "elements" {
-				print(t.Data)
-				mensen = append(mensen, t.Data)
-			}
-		}
-	}
-}

cache/cache.go

@@ -0,0 +1,18 @@
+package cache
+
+import (
+	"mensa/types"
+)
+
+func NewCache() *types.Cache {
+	cache := types.Cache{}
+	return &cache
+}
+
+func setCacheData(cache *types.Cache, key string, data string, lifetime ...int64) {
+	cache.SetData(key, data, lifetime...)
+}
+
+func getCacheData(cache *types.Cache) string {
+	return cache.GetData()
+}

fetch/fetch.go

@@ -0,0 +1,16 @@
+package fetch
+
+import (
+	"net/http"
+	"net/url"
+)
+
+func Fetch(path string) (*http.Response, error) {
+	baseurl := "https://www.imensa.de/"
+	queryurl := baseurl + "/" + path
+	u, err := url.ParseRequestURI(queryurl)
+	if err != nil {
+		return nil, err
+	}
+	return http.Get(u.String())
+}

main.go

@@ -0,0 +1,9 @@
+package main
+
+import (
+	"mensa/server"
+)
+
+func main() {
+	server.Run()
+}

scrape/scrape.go

@@ -0,0 +1,29 @@
+package scrape
+
+import (
+	"strings"
+
+	"golang.org/x/net/html"
+)
+
+func ScrapeBundesland(h string) []string {
+	tkn := html.NewTokenizer(strings.NewReader(h))
+
+	var mensen []string
+
+	for {
+		if tkn.Next() == html.ErrorToken {
+			return mensen
+		}
+
+		t := tkn.Token()
+		attr := t.Attr
+
+		for _, a := range attr {
+			if a.Key == "class" && a.Val == "elements" {
+				print(t.Data)
+				mensen = append(mensen, t.Data)
+			}
+		}
+	}
+}

server/server.go

@@ -0,0 +1,53 @@
+package server
+
+import (
+	"io"
+	"mensa/cache"
+	"mensa/fetch"
+	"mensa/scrape"
+	"mensa/types"
+	"net/http"
+
+	"github.com/gin-gonic/gin"
+)
+
+var c = cache.NewCache()
+
+func Run() {
+	r := gin.Default()
+	r.GET("/bl/:bundesland", bundesland)
+	r.Run("localhost:8080")
+}
+
+func bundesland(c *gin.Context) {
+	bundesland := c.Param("bundesland")
+	if bundesland == "" {
+		c.JSON(http.StatusBadRequest, gin.H{
+			"error": "bundesland is required",
+		})
+		return
+	}
+
+	if c.GetCacheData(bundesland) != "" {
+		return c.GetCacheData(bundesland)
+	}
+
+	resp, err := fetch.Fetch("bl/" + bundesland)
+	if err != nil {
+		c.JSON(http.StatusInternalServerError, gin.H{
+			"error": err.Error(),
+		})
+		return
+	}
+	defer resp.Body.Close()
+	d, err := io.ReadAll(resp.Body)
+	if err != nil {
+		c.JSON(http.StatusInternalServerError, gin.H{
+			"error": err.Error(),
+		})
+		return
+	}
+	html := string(d)
+	scraped := scrape.ScrapeBundesland(html)
+	c.JSON(http.StatusOK, scraped)
+}

types/bundesland.go

@@ -0,0 +1 @@
+package types

types/cache.go

@@ -0,0 +1,33 @@
+package types
+
+import "time"
+
+type Cache struct {
+	data        string
+	lastUpdated time.Time
+	lifetime    int64
+	key         string
+}
+
+func (c *Cache) SetData(key string, data string, lifetime ...int64) {
+	if len(lifetime) > 0 {
+		c.lifetime = lifetime[0]
+	} else {
+		c.lifetime = 60
+	}
+
+	c.data = data
+	c.lastUpdated = time.Now()
+}
+
+func (c *Cache) GetData() string {
+	if time.Now().Unix()-c.lastUpdated.Unix() > c.lifetime {
+		return ""
+	}
+
+	if c.data == "" {
+		return ""
+	}
+
+	return c.data
+}

types/mensa.go

@@ -0,0 +1 @@
+package types