Working Sampler and samples routes working

Signed-off-by: Felipe Cardoso <felipe.cardoso@hotmail.it>

backend/app/api/routes/samples.py

@@ -1,6 +1,7 @@
 from typing import List
 
 from fastapi import APIRouter, HTTPException, Query
+from fastapi.responses import Response
 
 from app.models.sample import Sample
 from app.services.sample_manager import SampleManager
@@ -8,7 +9,6 @@ from app.services.sample_manager import SampleManager
 router = APIRouter()
 sample_manager = SampleManager()
 
-
 @router.get("/list", response_model=List[Sample])
 async def list_samples(
         limit: int = Query(20, ge=1, le=100),
@@ -22,9 +22,10 @@ async def list_samples(
     except Exception as e:
         raise HTTPException(status_code=500, detail=str(e))
 
-
 @router.get("/latest", response_model=List[Sample])
-async def get_latest_samples(count: int = Query(5, ge=1, le=20)):
+async def get_latest_samples(
+        count: int = Query(5, ge=1, le=20)
+):
     """
     Get the most recent sample images
     """
@@ -32,3 +33,28 @@ async def get_latest_samples(count: int = Query(5, ge=1, le=20)):
         return await sample_manager.get_latest_samples(count)
     except Exception as e:
         raise HTTPException(status_code=500, detail=str(e))
+
+
+@router.get("/image/{filename}")
+async def get_sample_image(filename: str):
+    """
+    Get a specific sample image
+    """
+    try:
+        image_data = await sample_manager.get_sample_data(filename)
+
+        # Try to determine content type from filename
+        content_type = "image/jpeg"  # default
+        if filename.lower().endswith('.png'):
+            content_type = "image/png"
+        elif filename.lower().endswith('.gif'):
+            content_type = "image/gif"
+
+        return Response(
+            content=bytes(image_data),
+            media_type=content_type
+        )
+    except HTTPException:
+        raise
+    except Exception as e:
+        raise HTTPException(status_code=500, detail=str(e))

backend/app/core/config.py

@@ -5,7 +5,7 @@ class Settings(BaseSettings):
     # SFTP Settings
     SFTP_HOST: str
     SFTP_USER: str
-    SFTP_PASSWORD: str
+    SFTP_KEY_PATH: str = "~/.ssh/id_rsa"  # Default SSH key path
     SFTP_PATH: str
     SFTP_PORT: int = 22
 

backend/app/services/sample_manager.py

@@ -1,15 +1,159 @@
-from typing import List
+import asyncio
+import os
+from concurrent.futures import ThreadPoolExecutor
+from datetime import datetime
+from typing import List, Dict, Optional
 
+import paramiko
+from fastapi import HTTPException
+
+from app.core.config import settings
 from app.models.sample import Sample
 
 
 class SampleManager:
-    async def list_samples(self, limit: int, offset: int) -> List[Sample]:
-        # Implementation for listing samples from SFTP
-        # This is a placeholder - actual implementation needed
-        pass
+    def __init__(self):
+        self.sftp_client = None
+        self.cache_dir = "cache/samples"
+        self.last_sync = None
+        self.file_index: Dict[str, datetime] = {}
+        self.memory_cache: Dict[str, memoryview] = {}
+        self.executor = ThreadPoolExecutor(max_workers=4)
+        self._ensure_cache_dir()
 
-    async def get_latest_samples(self, count: int) -> List[Sample]:
-        # Implementation for getting latest samples
-        # This is a placeholder - actual implementation needed
-        pass
+    def _ensure_cache_dir(self):
+        """Ensure cache directory exists"""
+        os.makedirs(self.cache_dir, exist_ok=True)
+
+    async def _connect_sftp(self):
+        """Create SFTP connection using SSH key"""
+        try:
+            # Expand the key path (handles ~/)
+            key_path = os.path.expanduser(settings.SFTP_KEY_PATH)
+
+            # Create a new SSH client
+            ssh = paramiko.SSHClient()
+            ssh.set_missing_host_key_policy(paramiko.AutoAddPolicy())
+
+            # Connect using the SSH key
+            ssh.connect(
+                hostname=settings.SFTP_HOST,
+                username=settings.SFTP_USER,
+                port=settings.SFTP_PORT,
+                key_filename=key_path,
+            )
+
+            # Create SFTP client from the SSH client
+            self.sftp_client = ssh.open_sftp()
+        except Exception as e:
+            raise HTTPException(status_code=500, detail=f"SFTP Connection failed: {str(e)}")
+
+    def _disconnect_sftp(self):
+        """Close SFTP connection"""
+        if self.sftp_client:
+            self.sftp_client.close()
+            self.sftp_client = None
+
+    def _download_to_memory(self, remote_path: str) -> memoryview:
+        """Download file directly to memory"""
+        try:
+            with self.sftp_client.file(remote_path, 'rb') as remote_file:
+                # Read the entire file into memory
+                data = remote_file.read()
+                return memoryview(data)
+        except Exception as e:
+            raise HTTPException(status_code=500, detail=f"Download failed: {str(e)}")
+
+    async def _sync_files(self):
+        """Sync remote files to memory cache"""
+        if not self.sftp_client:
+            await self._connect_sftp()
+
+        try:
+            # Get remote files list - using listdir_attr directly on sftp_client
+            remote_files = self.sftp_client.listdir_attr(settings.SFTP_PATH)
+
+            # Update file index and download new files
+            for attr in remote_files:
+                remote_path = f"{settings.SFTP_PATH}/{attr.filename}"
+
+                # Check if file is new or updated
+                if (attr.filename not in self.file_index or
+                        datetime.fromtimestamp(attr.st_mtime) > self.file_index[attr.filename]):
+                    # Download file to memory
+                    loop = asyncio.get_event_loop()
+                    self.memory_cache[attr.filename] = await loop.run_in_executor(
+                        self.executor,
+                        self._download_to_memory,
+                        remote_path
+                    )
+                    self.file_index[attr.filename] = datetime.fromtimestamp(attr.st_mtime)
+
+            self.last_sync = datetime.now()
+
+        except Exception as e:
+            raise HTTPException(status_code=500, detail=f"Sync failed: {str(e)}")
+        finally:
+            self._disconnect_sftp()
+
+    async def ensure_synced(self, max_age_seconds: int = 30):
+        """Ensure memory cache is synced if too old"""
+        if (not self.last_sync or
+                (datetime.now() - self.last_sync).total_seconds() > max_age_seconds):
+            await self._sync_files()
+
+    async def list_samples(self, limit: int = 20, offset: int = 0) -> List[Sample]:
+        """List sample images with pagination"""
+        await self.ensure_synced()
+
+        # Get sorted list of files
+        files = sorted(
+            [(f, self.file_index[f]) for f in self.file_index],
+            key=lambda x: x[1],
+            reverse=True
+        )
+
+        # Apply pagination
+        files = files[offset:offset + limit]
+
+        # Create Sample objects
+        return [
+            Sample(
+                filename=filename,
+                url=f"/api/v1/samples/image/{filename}",
+                created_at=created_at
+            )
+            for filename, created_at in files
+        ]
+
+    async def get_latest_samples(self, count: int = 5) -> List[Sample]:
+        """Get most recent samples"""
+        return await self.list_samples(limit=count, offset=0)
+
+    async def get_sample_data(self, filename: str) -> Optional[memoryview]:
+        """Get image data from memory cache"""
+        await self.ensure_synced()
+
+        if filename not in self.memory_cache:
+            raise HTTPException(status_code=404, detail="Sample not found")
+
+        return self.memory_cache[filename]
+
+    def cleanup_old_files(self, max_files: int = 1000):
+        """Cleanup old files from memory cache"""
+        if len(self.memory_cache) > max_files:
+            # Sort files by date and keep only the newest
+            files = sorted(
+                [(f, self.file_index[f]) for f in self.file_index],
+                key=lambda x: x[1],
+                reverse=True
+            )
+
+            # Keep only max_files
+            files_to_keep = {f[0] for f in files[:max_files]}
+
+            # Remove old files from cache
+            for filename in list(self.memory_cache.keys()):
+                if filename not in files_to_keep:
+                    del self.memory_cache[filename]
+                    del self.file_index[filename]