admin: Create a GitImporter based on git binaries

.drone.yml

@@ -28,6 +28,7 @@ steps:
     image: golang:alpine
     commands:
       - apk --no-cache add build-base
+      - go vet -v -tags gitgo srs.epita.fr/fic-server/admin
       - go vet -v srs.epita.fr/fic-server/admin
       - go vet -v srs.epita.fr/fic-server/backend
       - go vet -v srs.epita.fr/fic-server/frontend
@@ -38,6 +39,7 @@ steps:
   - name: build admin
     image: golang:alpine
     commands:
+      - go build -v -tags gitgo -o deploy/admin-gitgo-${DRONE_STAGE_OS}-${DRONE_STAGE_ARCH} srs.epita.fr/fic-server/admin
       - go build -v -o deploy/admin-${DRONE_STAGE_OS}-${DRONE_STAGE_ARCH} srs.epita.fr/fic-server/admin
       - tar chjf deploy/htdocs-admin.tar.bz2 htdocs-admin
     environment:

Dockerfile-admin

@@ -15,7 +15,12 @@ RUN go build -v -o admin/admin ./admin
 
 FROM alpine
 
-RUN apk add --no-cache openssl ca-certificates
+RUN apk add --no-cache \
+        ca-certificates \
+        git \
+        git-lfs \
+        openssh-client-default \
+        openssl
 
 EXPOSE 8081
 

admin/sync/importer_git.go

@@ -1,7 +1,9 @@
+//go:build gitgo
+// +build gitgo
+
 package sync
 
 import (
-	"bufio"
 	"io/ioutil"
 	"log"
 	"os"
@@ -62,15 +64,6 @@ func (i GitImporter) Kind() string {
 	return "git originated from " + i.Remote + " on " + i.li.Kind() + ", currently on commit " + gitinfo
 }
 
-func countFileInDir(dirname string) (int, error) {
-	files, err := os.ReadDir(dirname)
-	if err != nil {
-		return 0, err
-	}
-
-	return len(files), nil
-}
-
 func (i GitImporter) Init() error {
 	// Check if the directory exists, create it if needed
 	if err := i.li.Init(); err != nil {
@@ -130,27 +123,3 @@ func (i GitImporter) Sync() error {
 	})
 	return err
 }
-
-func (i GitImporter) exists(filename string) bool {
-	return i.li.exists(filename)
-}
-
-func (i GitImporter) toURL(filename string) string {
-	return i.li.toURL(filename)
-}
-
-func (i GitImporter) importFile(URI string, next func(string, string) (interface{}, error)) (interface{}, error) {
-	return i.li.importFile(URI, next)
-}
-
-func (i GitImporter) getFile(filename string, writer *bufio.Writer) error {
-	return i.li.getFile(filename, writer)
-}
-
-func (i GitImporter) listDir(filename string) ([]string, error) {
-	return i.li.listDir(filename)
-}
-
-func (i GitImporter) stat(filename string) (os.FileInfo, error) {
-	return i.li.stat(filename)
-}

admin/sync/importer_git_common.go

@@ -0,0 +1,39 @@
+package sync
+
+import (
+	"bufio"
+	"os"
+)
+
+func countFileInDir(dirname string) (int, error) {
+	files, err := os.ReadDir(dirname)
+	if err != nil {
+		return 0, err
+	}
+
+	return len(files), nil
+}
+
+func (i GitImporter) exists(filename string) bool {
+	return i.li.exists(filename)
+}
+
+func (i GitImporter) toURL(filename string) string {
+	return i.li.toURL(filename)
+}
+
+func (i GitImporter) importFile(URI string, next func(string, string) (interface{}, error)) (interface{}, error) {
+	return i.li.importFile(URI, next)
+}
+
+func (i GitImporter) getFile(filename string, writer *bufio.Writer) error {
+	return i.li.getFile(filename, writer)
+}
+
+func (i GitImporter) listDir(filename string) ([]string, error) {
+	return i.li.listDir(filename)
+}
+
+func (i GitImporter) stat(filename string) (os.FileInfo, error) {
+	return i.li.stat(filename)
+}

admin/sync/importer_gitbin.go

@@ -0,0 +1,83 @@
+//go:build !gitgo
+// +build !gitgo
+
+package sync
+
+import (
+	"bytes"
+	"fmt"
+	"os/exec"
+	"strings"
+)
+
+// GitImporter implements an Importer, where files to imports are located
+// inside a local directory from your filesystem, backed by git (binary).
+type GitImporter struct {
+	li     LocalImporter
+	Remote string
+}
+
+func NewGitImporter(li LocalImporter, remote string) GitImporter {
+	return GitImporter{
+		li:     li,
+		Remote: remote,
+	}
+}
+
+func (i GitImporter) Kind() string {
+	cmdshow := exec.Command("git", "-C", i.li.Base, "show")
+	var outshow bytes.Buffer
+	cmdshow.Stdout = &outshow
+	err := cmdshow.Run()
+
+	var commit string
+	if err != nil {
+		commit = fmt.Sprintf("error (%s)", err.Error())
+	} else {
+		commit, err = outshow.ReadString('\n')
+		if err == nil {
+			commit = strings.TrimPrefix(commit, "commit ")
+		} else {
+			commit = fmt.Sprintf("error (%s)", err.Error())
+		}
+	}
+
+	return "git originated from " + i.Remote + " on " + i.li.Kind() + ", currently on commit " + commit
+}
+
+func (i GitImporter) Init() error {
+	// Check if the directory exists, create it if needed
+	if err := i.li.Init(); err != nil {
+		return err
+	}
+
+	// If the directory is empty, clone it
+	if n, err := countFileInDir(i.li.Base); err != nil {
+		return err
+	} else if n == 0 {
+		cmdclone := exec.Command("git", "-C", i.li.Base, "clone", "--recursive", i.Remote)
+		stdout, err := cmdclone.CombinedOutput()
+		if err != nil {
+			return fmt.Errorf("%w:\n%s", err, stdout)
+		}
+	}
+
+	// Check if the .git directory exists, change the origin remote to our
+	cmdremote := exec.Command("git", "-C", i.li.Base, "remote", "set-url", "origin", i.Remote)
+	stdout, err := cmdremote.CombinedOutput()
+	if err != nil {
+		return fmt.Errorf("%w:\n%s", err, stdout)
+	}
+
+	return nil
+}
+
+func (i GitImporter) Sync() error {
+	cmdremote := exec.Command("git", "-C", i.li.Base, "pull", "--rebase", "--force", "--recurse-submodules=yes", "origin")
+	stdout, err := cmdremote.CombinedOutput()
+	if err != nil {
+		return fmt.Errorf("%w:\n%s", err, stdout)
+	}
+
+	return nil
+}