change hash algorithm compatible for fetchNextcloudApp

go.mod

@@ -3,3 +3,12 @@ module git.helsinki.tools/helsinki-systems/nc4nix
 go 1.17
 
 require github.com/hashicorp/go-version v1.6.0
+
+require (
+	github.com/codeclysm/extract/v3 v3.1.1 // indirect
+	github.com/h2non/filetype v1.1.3 // indirect
+	github.com/juju/errors v0.0.0-20181118221551-089d3ea4e4d5 // indirect
+	github.com/klauspost/compress v1.15.13 // indirect
+	github.com/nix-community/go-nix v0.0.0-20231219074122-93cb24a86856 // indirect
+	github.com/ulikunitz/xz v0.5.11 // indirect
+)

go.sum

@@ -1,2 +1,14 @@
+github.com/codeclysm/extract/v3 v3.1.1 h1:iHZtdEAwSTqPrd+1n4jfhr1qBhUWtHlMTjT90+fJVXg=
+github.com/codeclysm/extract/v3 v3.1.1/go.mod h1:ZJi80UG2JtfHqJI+lgJSCACttZi++dHxfWuPaMhlOfQ=
+github.com/h2non/filetype v1.1.3 h1:FKkx9QbD7HR/zjK1Ia5XiBsq9zdLi5Kf3zGyFTAFkGg=
+github.com/h2non/filetype v1.1.3/go.mod h1:319b3zT68BvV+WRj7cwy856M2ehB3HqNOt6sy1HndBY=
 github.com/hashicorp/go-version v1.6.0 h1:feTTfFNnjP967rlCxM/I9g701jU+RN74YKx2mOkIeek=
 github.com/hashicorp/go-version v1.6.0/go.mod h1:fltr4n8CU8Ke44wwGCBoEymUuxUHl09ZGVZPK5anwXA=
+github.com/juju/errors v0.0.0-20181118221551-089d3ea4e4d5 h1:rhqTjzJlm7EbkELJDKMTU7udov+Se0xZkWmugr6zGok=
+github.com/juju/errors v0.0.0-20181118221551-089d3ea4e4d5/go.mod h1:W54LbzXuIE0boCoNJfwqpmkKJ1O4TCTZMetAt6jGk7Q=
+github.com/klauspost/compress v1.15.13 h1:NFn1Wr8cfnenSJSA46lLq4wHCcBzKTSjnBIexDMMOV0=
+github.com/klauspost/compress v1.15.13/go.mod h1:QPwzmACJjUTFsnSHH934V6woptycfrDDJnH7hvFVbGM=
+github.com/nix-community/go-nix v0.0.0-20231219074122-93cb24a86856 h1:CHnKW7ZH43KDkO9vDazQefi82Z0l1smKhSOpMsV1A9I=
+github.com/nix-community/go-nix v0.0.0-20231219074122-93cb24a86856/go.mod h1:0FdXufC8BrrWsr65fGYC0fI6hlk4ku+JHGUiYhX/6g4=
+github.com/ulikunitz/xz v0.5.11 h1:kpFauv27b6ynzBNT/Xy+1k+fK4WswhN/6PN5WhFAGw8=
+github.com/ulikunitz/xz v0.5.11/go.mod h1:nbz6k7qbPmH4IRqmfOplQw/tblSgqTqBwxkY0oWt/14=

main.go

@@ -10,8 +10,15 @@ import (
 	"net/http"
 	"os"
 	"strings"
+	"context"
+	"bytes"
+	"path/filepath"
 
 	"github.com/hashicorp/go-version"
+
+	"github.com/nix-community/go-nix/pkg/nar"
+	"github.com/nix-community/go-nix/pkg/nixbase32"
+	"github.com/codeclysm/extract/v3"
 )
 
 var DEBUG bool
@@ -57,6 +64,7 @@ type AppJson map[string]App
 func major(t string) string {
 	return strings.Split(t, ".")[0]
 }
+
 func loadFile(t string) (AppJson, error) {
 	fname := major(t) + ".json"
 	log.Print("Loading " + fname)
@@ -109,6 +117,9 @@ func writeFile(t string, c AppJson) {
 }
 
 func prefetch(url string) (string, error) {
+	h := sha256.New()
+	var sha256 string
+
 	resp, err := http.Get(url)
 	if err != nil || resp.StatusCode != http.StatusOK {
 		log.Print("Prefetch failed for: ", url, err)
@@ -118,9 +129,30 @@ func prefetch(url string) (string, error) {
 	contents, err := ioutil.ReadAll(resp.Body)
 	if err != nil {
 		log.Print("Prefetch failed reading body for: ", url, err)
+	}
+	dname, err := os.MkdirTemp("", "")
+	if err != nil {
+		log.Fatal(err)
+	}
+	buffer := bytes.NewBuffer(contents)
+	extract.Archive(context.Background(), buffer, dname, nil)
+	entries, err := os.ReadDir(dname)
+	if err != nil {
 		return "", err
 	}
-	sha256 := fmt.Sprintf("%x", sha256.Sum256(contents))
+	var entryPath string
+	for _, entry := range entries {
+		if entry.IsDir() {
+			entryPath = filepath.Join(dname, entry.Name())
+			break
+		}
+	}
+	err = nar.DumpPath(h, entryPath)
+	if err != nil {
+		panic(err)
+	}
+	defer os.RemoveAll(dname)
+	sha256 = nixbase32.EncodeToString(h.Sum(nil))
 
 	return sha256, err
 }