feat: mail attachment support — sync, display, download, upload

app/plugins/builtins/mail/routes.py

@@ -12,7 +12,7 @@ import uuid
 from datetime import UTC, datetime
 from pathlib import Path
 
-from fastapi import APIRouter, Body, Depends, HTTPException, Query
+from fastapi import APIRouter, Body, Depends, File, HTTPException, Query, UploadFile
 from fastapi.responses import StreamingResponse
 from sqlalchemy import and_, desc, func, or_, select
 from sqlalchemy.ext.asyncio import AsyncSession
@@ -58,8 +58,13 @@ from app.plugins.builtins.mail.schemas import (
     VacationConfig,
 )
 from app.plugins.builtins.mail.services import (
+    MAX_ATTACHMENT_SIZE,
+    _attachment_storage_path,
+    _sanitize_filename,
+    _save_attachment_to_storage,
     account_to_response,
     apply_rules_to_mail,
+    attachment_to_response,
     create_mail_account,
     encrypt_password,
     folder_to_response,
@@ -94,6 +99,35 @@ def _parse_uuid(val: str, field: str = "id") -> uuid.UUID:
         ) from None
 
 
+def _resolve_attachment_paths(attachment_ids: list[str]) -> list[dict]:
+    """Resolve temporary attachment upload IDs to file paths on disk.
+
+    Each uploaded attachment is stored under
+    ``<storage>/mail_uploads/<temp_id>/<filename>``.  We scan the
+    directory for the single file inside and return its metadata.
+    """
+    import os
+
+    resolved: list[dict] = []
+    base_dir = os.environ.get("STORAGE_PATH", "/tmp")
+    for att_id in attachment_ids:
+        upload_dir = os.path.join(base_dir, "mail_uploads", att_id)
+        if not os.path.isdir(upload_dir):
+            continue
+        for fname in os.listdir(upload_dir):
+            fpath = os.path.join(upload_dir, fname)
+            if os.path.isfile(fpath):
+                resolved.append(
+                    {
+                        "path": fpath,
+                        "filename": fname,
+                        "mime_type": "application/octet-stream",
+                    }
+                )
+                break
+    return resolved
+
+
 async def _get_account(
     db: AsyncSession, account_id: uuid.UUID, tenant_id: uuid.UUID, user_id: uuid.UUID
 ) -> MailAccount:
@@ -521,6 +555,62 @@ async def delete_folder(
     await db.delete(folder)
 
 
+# ─── Attachment Upload (F-MAIL-04) ───
+
+
+@router.post("/upload-attachment")
+async def upload_attachment(
+    file: UploadFile = File(...),
+    db: AsyncSession = Depends(get_db),
+    current_user: dict = Depends(get_current_user),
+):
+    """Upload a file to be attached to an outgoing email.
+
+    Returns a temporary attachment ID that can be passed in the
+    `attachments` list of the send-mail request.
+    """
+    tenant_id = uuid.UUID(current_user["tenant_id"])
+    user_id = uuid.UUID(current_user["user_id"])
+
+    # Read file content and check size
+    content = await file.read()
+    if len(content) > MAX_ATTACHMENT_SIZE:
+        raise HTTPException(
+            413,
+            detail={
+                "detail": f"File exceeds maximum size of {MAX_ATTACHMENT_SIZE // (1024 * 1024)} MB",
+                "code": "file_too_large",
+            },
+        )
+
+    # Generate a temporary attachment ID and store the file
+    temp_id = str(uuid.uuid4())
+    safe_filename = _sanitize_filename(file.filename or "attachment")
+    mime_type = file.content_type or "application/octet-stream"
+
+    # Store in a temp directory keyed by the temp_id
+    import os
+
+    temp_dir = os.path.join(
+        os.environ.get("STORAGE_PATH", "/tmp"), "mail_uploads", temp_id
+    )
+    os.makedirs(temp_dir, exist_ok=True)
+    file_path = os.path.join(temp_dir, safe_filename)
+
+    import aiofiles
+
+    async with aiofiles.open(file_path, "wb") as f:
+        await f.write(content)
+
+    return {
+        "id": temp_id,
+        "filename": safe_filename,
+        "mime_type": mime_type,
+        "size_bytes": len(content),
+        "path": file_path,
+    }
+
+
 # ─── Send (F-MAIL-02) ───
 
 
@@ -574,6 +664,7 @@ async def send_mail(
         in_reply_to=data.in_reply_to,
         references_header=data.references_header,
         signature=signature,
+        attachment_paths=_resolve_attachment_paths(data.attachments),
     )
     if result.get("status") == "error":
         raise HTTPException(