From 4ef0f108ea6b4c412cd1f974f5bd82c8e334b630 Mon Sep 17 00:00:00 2001
From: Alex Blank <alexblank@fastmail.com>
Date: Fri, 22 May 2026 21:19:15 +0000
Subject: [PATCH] fix: use SSH key during repository preflight and clone

---
 apps/api/src/api/git_repositories.py | 68 +++++++++++++++++++++++++---
 1 file changed, 62 insertions(+), 6 deletions(-)

diff --git a/apps/api/src/api/git_repositories.py b/apps/api/src/api/git_repositories.py
index e5045fb..6d0e8a6 100644
--- a/apps/api/src/api/git_repositories.py
+++ b/apps/api/src/api/git_repositories.py
@@ -35,6 +35,7 @@ from src.utils.git_control import (
 )
 from src.utils.git_history import get_commit_detail, get_commit_history
 from src.utils.git_url_parser import parse_git_url
+from src.services.ssh_keys import _get_fernet
 
 router = APIRouter(prefix="/projects", tags=["git-repositories"])
 
@@ -95,19 +96,61 @@ def _build_provider_clone_url(owner: str, repo: str) -> str:
     return f"git@git.commumedia.org:{owner}/{repo}.git"
 
 
-def _preflight_remote_repository(remote_url: str) -> None:
+def _prepare_ssh_env(ssh_key: SSHKey | None) -> dict | None:
+    """Prepare environment variables for git commands with SSH authentication.
+    
+    Returns a dict of extra env vars, or None if no SSH key provided.
+    The caller is responsible for cleaning up the temporary key file.
+    """
+    if ssh_key is None:
+        return None
+    
+    import tempfile
+    
+    # Decrypt private key
+    fernet = _get_fernet()
+    private_key = fernet.decrypt(ssh_key.private_key_encrypted.encode()).decode()
+    
+    # Write to temp file with restricted permissions
+    fd, key_path = tempfile.mkstemp(prefix="ssh_key_")
+    try:
+        os.write(fd, private_key.encode())
+    finally:
+        os.close(fd)
+    os.chmod(key_path, 0o600)
+    
+    # Return env vars and the key path for cleanup
+    env = {
+        "GIT_SSH_COMMAND": f"ssh -i {key_path} -o StrictHostKeyChecking=no -o UserKnownHostsFile=/dev/null"
+    }
+    return env, key_path
+
+
+def _preflight_remote_repository(remote_url: str, ssh_key: SSHKey | None = None) -> None:
     """Verify a remote repository is reachable before cloning."""
+    env = None
+    key_path = None
+    
+    if ssh_key is not None:
+        ssh_result = _prepare_ssh_env(ssh_key)
+        if ssh_result:
+            env, key_path = ssh_result
+    
     try:
         result = subprocess.run(
             ["git", "ls-remote", remote_url],
             capture_output=True,
             text=True,
             timeout=60,
+            env={**os.environ, **env} if env else None,
         )
     except subprocess.TimeoutExpired:
         raise HTTPException(status_code=status.HTTP_400_BAD_REQUEST, detail="remote repository check timed out")
     except FileNotFoundError:
         raise HTTPException(status_code=status.HTTP_500_INTERNAL_SERVER_ERROR, detail="git command not found")
+    finally:
+        if key_path and os.path.exists(key_path):
+            os.unlink(key_path)
 
     if result.returncode != 0:
         raise HTTPException(
@@ -116,18 +159,30 @@ def _preflight_remote_repository(remote_url: str) -> None:
         )
 
 
-def _clone_working_repository(remote_url: str, repo_path: str) -> None:
+def _clone_working_repository(remote_url: str, repo_path: str, ssh_key: SSHKey | None = None) -> None:
+    env = None
+    key_path = None
+    
+    if ssh_key is not None:
+        ssh_result = _prepare_ssh_env(ssh_key)
+        if ssh_result:
+            env, key_path = ssh_result
+    
     try:
         result = subprocess.run(
             ["git", "clone", remote_url, repo_path],
             capture_output=True,
             text=True,
             timeout=300,
+            env={**os.environ, **env} if env else None,
         )
     except subprocess.TimeoutExpired:
         raise HTTPException(status_code=status.HTTP_400_BAD_REQUEST, detail="clone operation timed out")
     except FileNotFoundError:
         raise HTTPException(status_code=status.HTTP_500_INTERNAL_SERVER_ERROR, detail="git command not found")
+    finally:
+        if key_path and os.path.exists(key_path):
+            os.unlink(key_path)
 
     if result.returncode != 0:
         raise HTTPException(
@@ -352,11 +407,9 @@ async def create_repository(
         if parse_result["base_url"]:
             remote_url = parse_result["base_url"]
 
-    if remote_url:
-        _preflight_remote_repository(remote_url)
-
     # Validate SSH key if provided
     ssh_key_id = None
+    ssh_key = None
     if data.ssh_key_id:
         try:
             ssh_key_id = uuid.UUID(data.ssh_key_id)
@@ -369,13 +422,16 @@ async def create_repository(
         if ssh_key.user_id != user_id and ssh_key.project_id != project_id:
             raise HTTPException(status_code=status.HTTP_403_FORBIDDEN, detail="ssh key does not belong to user or project")
 
+    if remote_url:
+        _preflight_remote_repository(remote_url, ssh_key)
+
     repo_path = _get_repo_path(user_id, project_id, data.name)
 
     # Ensure parent directory exists
     os.makedirs(os.path.dirname(repo_path), exist_ok=True)
 
     if remote_url:
-        _clone_working_repository(remote_url, repo_path)
+        _clone_working_repository(remote_url, repo_path, ssh_key)
     else:
         _init_working_repository(repo_path)