persist the httpcache to the filesystem

1 files changed, 17 insertions, 0 deletions

diff --git a/cmd/generate/httpcache.go b/cmd/generate/httpcache.go
index 87d2fb5..cff0c7c 100644
--- a/cmd/generate/httpcache.go
+++ b/cmd/generate/httpcache.go
@@ -5,6 +5,9 @@ import (
 	"fmt"
 	"io"
 	"net/http"
+	"net/url"
+	"os"
+	"path/filepath"
 )
 
 var httpCache = map[string]string{}
@@ -13,6 +16,17 @@ func httpGet(u string) (string, error) {
 	if cache, ok := httpCache[u]; ok {
 		return cache, nil
 	}
+	if err := os.Mkdir(".http-cache", 0777); err != nil && !os.IsExist(err) {
+		return "", err
+	}
+	cacheFile := filepath.Join(".http-cache", url.QueryEscape(u))
+	if bs, err := os.ReadFile(cacheFile); err == nil {
+		httpCache[u] = string(bs)
+		return httpCache[u], nil
+	} else if !os.IsNotExist(err) {
+		return "", err
+	}
+
 	fmt.Printf("GET %q...", u)
 	resp, err := http.Get(u)
 	if err != nil {
@@ -29,6 +43,9 @@ func httpGet(u string) (string, error) {
 		return "", err
 	}
 	fmt.Printf(" ok\n")
+	if err := os.WriteFile(cacheFile, bs, 0666); err != nil {
+		return "", err
+	}
 	httpCache[u] = string(bs)
 	return httpCache[u], nil
 }