chore: derive version from git tags via hatch-vcs

Replace hardcoded version in pyproject.toml with hatch-vcs so the
package version is read from git tags at build time. Dockerfile
accepts a VERSION build arg and passes it as HATCH_VCS_PRETEND_VERSION
for builds without a git checkout. Makefile _tag target now rebuilds
the container with the correct version automatically.

.gitignore

@@ -45,3 +45,7 @@ uv.lock
 
 # Docker volumes
 minio_data/
+
+# Local configuration overrides
+docker-compose.yml
+ca-bundle.pem

Dockerfile

@@ -23,10 +23,6 @@ RUN wget -O /app/uv-x86_64-unknown-linux-musl.tar.gz https://github.com/astral-s
     chmod +x /usr/local/bin/uv && \
     uv --version
 
-# Copy CA bundle from host
-COPY ca-bundle.pem /app/ca-bundle.pem
-RUN chmod 644 /app/ca-bundle.pem
-
 # Create non-root user first
 RUN adduser -D -s /bin/sh appuser && \
     chown -R appuser:appuser /app
@@ -36,11 +32,13 @@ COPY --chown=appuser:appuser pyproject.toml uv.lock README.md ./
 
 # Switch to appuser and install Python dependencies
 USER appuser
-RUN uv sync --frozen
+ARG VERSION=dev
+RUN HATCH_VCS_PRETEND_VERSION=${VERSION} uv sync --frozen
 
 # Copy application source
 COPY --chown=appuser:appuser src/ ./src/
 COPY --chown=appuser:appuser remotes.yaml ./
+COPY --chown=appuser:appuser ca-bundle.pem ./
 
 # Expose port
 EXPOSE 8000

Makefile

@@ -26,8 +26,6 @@ format:
 	uv run ruff format .
 
 run:
-	uv venv --python 3.11 && \
-	source .venv/bin/activate && \
 	uv run python -m src.artifactapi.main
 
 docker-up:
@@ -47,3 +45,27 @@ docker-clean:
 	docker system prune -f
 
 docker-restart: docker-down docker-up
+
+# Bump helpers — reads the latest semver tag and creates the next one.
+# If no tag exists yet, starts from v0.0.0.
+_LATEST := $(shell git tag --sort=-v:refname | grep -E '^v[0-9]+\.[0-9]+\.[0-9]+$$' | head -1)
+_BASE   := $(if $(_LATEST),$(_LATEST),v0.0.0)
+_MAJ    := $(shell echo $(_BASE) | sed 's/^v//' | cut -d. -f1)
+_MIN    := $(shell echo $(_BASE) | sed 's/^v//' | cut -d. -f2)
+_PAT    := $(shell echo $(_BASE) | sed 's/^v//' | cut -d. -f3)
+
+patch:
+	@NEW=v$(_MAJ).$(_MIN).$(shell expr $(_PAT) + 1); \
+	git tag $$NEW && echo "Tagged $$NEW" && $(MAKE) _tag TAG=$$NEW
+
+minor:
+	@NEW=v$(_MAJ).$(shell expr $(_MIN) + 1).0; \
+	git tag $$NEW && echo "Tagged $$NEW" && $(MAKE) _tag TAG=$$NEW
+
+major:
+	@NEW=v$(shell expr $(_MAJ) + 1).0.0; \
+	git tag $$NEW && echo "Tagged $$NEW" && $(MAKE) _tag TAG=$$NEW
+
+_tag:
+	git push origin $(TAG)
+	docker-compose build --no-cache --build-arg VERSION=$(TAG:v%=%)

docker-compose.yml

@@ -1,86 +0,0 @@
-version: '3.8'
-
-services:
-  artifactapi:
-    build:
-      context: .
-      dockerfile: Dockerfile
-      no_cache: true
-    ports:
-      - "8000:8000"
-    environment:
-      - CONFIG_PATH=/app/remotes.yaml
-      - DBHOST=postgres
-      - DBPORT=5432
-      - DBUSER=artifacts
-      - DBPASS=artifacts123
-      - DBNAME=artifacts
-      - REDIS_URL=redis://redis:6379
-      - MINIO_ENDPOINT=minio:9000
-      - MINIO_ACCESS_KEY=minioadmin
-      - MINIO_SECRET_KEY=minioadmin
-      - MINIO_BUCKET=artifacts
-      - MINIO_SECURE=false
-    depends_on:
-      postgres:
-        condition: service_healthy
-      redis:
-        condition: service_healthy
-      minio:
-        condition: service_healthy
-    healthcheck:
-      test: ["CMD", "curl", "-f", "http://localhost:8000/health"]
-      interval: 30s
-      timeout: 10s
-      retries: 3
-
-  minio:
-    image: minio/minio:latest
-    ports:
-      - "9000:9000"
-      - "9001:9001"
-    environment:
-      MINIO_ROOT_USER: minioadmin
-      MINIO_ROOT_PASSWORD: minioadmin
-    command: server /data --console-address ":9001"
-    volumes:
-      - minio_data:/data
-    healthcheck:
-      test: ["CMD", "curl", "-f", "http://localhost:9000/minio/health/live"]
-      interval: 30s
-      timeout: 20s
-      retries: 3
-
-  redis:
-    image: redis:7-alpine
-    ports:
-      - "6379:6379"
-    volumes:
-      - redis_data:/data
-    command: redis-server --save 20 1
-    healthcheck:
-      test: ["CMD", "redis-cli", "ping"]
-      interval: 30s
-      timeout: 10s
-      retries: 3
-
-  postgres:
-    image: postgres:15-alpine
-    ports:
-      - "5432:5432"
-    environment:
-      POSTGRES_DB: artifacts
-      POSTGRES_USER: artifacts
-      POSTGRES_PASSWORD: artifacts123
-    volumes:
-      - postgres_data:/var/lib/postgresql/data
-    healthcheck:
-      test: ["CMD-SHELL", "pg_isready -U artifacts -d artifacts"]
-      interval: 30s
-      timeout: 10s
-      retries: 3
-
-volumes:
-  minio_data:
-  redis_data:
-  postgres_data:

pyproject.toml

@@ -1,6 +1,6 @@
 [project]
 name = "artifactapi"
-version = "2.0.0"
+dynamic = ["version"]
 description = "Generic artifact caching system with support for various package managers"
 
 dependencies = [
@@ -23,9 +23,12 @@ license = {text = "MIT"}
 artifactapi = "artifactapi.main:main"
 
 [build-system]
-requires = ["hatchling"]
+requires = ["hatchling", "hatch-vcs"]
 build-backend = "hatchling.build"
 
+[tool.hatch.version]
+source = "vcs"
+
 [tool.hatch.metadata]
 allow-direct-references = true
 

src/artifactapi/cache.py

@@ -23,8 +23,20 @@ class RedisCache:
             file_path.endswith("APKINDEX.tar.gz")
             or file_path.endswith("Packages.gz")
             or file_path.endswith("repomd.xml")
-            or "repodata/" in file_path
-            and file_path.endswith((".xml", ".xml.gz", ".xml.bz2", ".xml.xz"))
+            or ("repodata/" in file_path
+                and file_path.endswith((
+                    ".xml", ".xml.gz", ".xml.bz2", ".xml.xz", ".xml.zck", ".xml.zst",
+                    ".sqlite", ".sqlite.gz", ".sqlite.bz2", ".sqlite.xz", ".sqlite.zck", ".sqlite.zst",
+                    ".yaml.xz", ".yaml.gz", ".yaml.bz2", ".yaml.zst",
+                    ".asc", ".txt"
+                )))
+            # Docker tag-based manifests are mutable (index); digest-pinned are immutable (file)
+            or (
+                "/manifests/" in file_path
+                and not file_path.split("/manifests/", 1)[1].startswith("sha256:")
+            )
+            or "/tags/list" in file_path
+            or file_path.endswith("/tags/list")
         )
 
     def get_index_cache_key(self, remote_name: str, path: str) -> str:
@@ -61,9 +73,19 @@ class RedisCache:
             return
 
         try:
-            # Get the S3 key and remove it
-            s3_key = storage.get_object_key_from_path(remote_name, path)
-            if storage.exists(s3_key):
-                storage.client.delete_object(Bucket=storage.bucket, Key=s3_key)
+            # Construct the URL the same way as in the main flow
+            from .config import ConfigManager
+            import os
+            config_path = os.environ.get("CONFIG_PATH")
+            if config_path:
+                config = ConfigManager(config_path)
+                remote_config = config.get_remote_config(remote_name)
+                if remote_config:
+                    base_url = remote_config.get("base_url")
+                    if base_url:
+                        # Use hierarchical path-based key (same as cache_single_artifact)
+                        s3_key = storage.get_object_key(remote_name, path)
+                        if storage.exists(s3_key):
+                            storage.client.delete_object(Bucket=storage.bucket, Key=s3_key)
         except Exception:
             pass

src/artifactapi/docker_auth.py

@@ -0,0 +1,96 @@
+import time
+import logging
+import re
+from typing import Optional
+import httpx
+
+logger = logging.getLogger(__name__)
+
+# In-memory token cache: key -> (token, expires_at)
+_token_cache: dict[str, tuple[str, float]] = {}
+
+_WWW_AUTH_RE = re.compile(
+    r'Bearer\s+realm="(?P<realm>[^"]+)"'
+    r'(?:,service="(?P<service>[^"]*)")?'
+    r'(?:,scope="(?P<scope>[^"]*)")?',
+    re.IGNORECASE,
+)
+
+
+def _cache_key(realm: str, service: str, scope: str, username: Optional[str]) -> str:
+    return f"{realm}|{service}|{scope}|{username or ''}"
+
+
+def _get_cached_token(key: str) -> Optional[str]:
+    entry = _token_cache.get(key)
+    if entry and entry[1] > time.time():
+        return entry[0]
+    _token_cache.pop(key, None)
+    return None
+
+
+def _store_token(key: str, token: str, expires_in: int) -> None:
+    # Expire 30s early to avoid using a token right as it expires
+    _token_cache[key] = (token, time.time() + max(expires_in - 30, 10))
+
+
+async def fetch_token(
+    realm: str,
+    service: str,
+    scope: str,
+    username: Optional[str] = None,
+    password: Optional[str] = None,
+) -> Optional[str]:
+    """Fetch a Bearer token from a Docker registry auth server."""
+    key = _cache_key(realm, service, scope, username)
+    cached = _get_cached_token(key)
+    if cached:
+        return cached
+
+    params: dict[str, str] = {}
+    if service:
+        params["service"] = service
+    if scope:
+        params["scope"] = scope
+
+    auth = (username, password) if username and password else None
+
+    try:
+        async with httpx.AsyncClient(follow_redirects=True) as client:
+            response = await client.get(realm, params=params, auth=auth)
+            response.raise_for_status()
+            data = response.json()
+    except Exception as e:
+        logger.warning(f"Docker token fetch failed ({realm}): {e}")
+        return None
+
+    token = data.get("token") or data.get("access_token")
+    if not token:
+        logger.warning(f"Docker token response missing token field: {data}")
+        return None
+
+    expires_in = int(data.get("expires_in", 300))
+    _store_token(key, token, expires_in)
+    logger.debug(f"Docker token obtained (realm={realm}, service={service}, scope={scope}, expires_in={expires_in}s)")
+    return token
+
+
+def parse_www_authenticate(header: str) -> Optional[tuple[str, str, str]]:
+    """Parse WWW-Authenticate: Bearer header. Returns (realm, service, scope) or None."""
+    m = _WWW_AUTH_RE.search(header)
+    if not m:
+        return None
+    return m.group("realm"), m.group("service") or "", m.group("scope") or ""
+
+
+async def get_docker_token_for_response(
+    www_authenticate: str,
+    username: Optional[str] = None,
+    password: Optional[str] = None,
+) -> Optional[str]:
+    """Given a WWW-Authenticate header value, fetch and return a Bearer token."""
+    parsed = parse_www_authenticate(www_authenticate)
+    if not parsed:
+        return None
+    realm, service, scope = parsed
+    return await fetch_token(realm, service, scope, username, password)

src/artifactapi/main.py

@@ -1,18 +1,28 @@
 import os
 import re
+import json
 import hashlib
+import logging
 from typing import Dict, Any, Optional
 import httpx
-from fastapi import FastAPI, HTTPException, Response, Query, File, UploadFile
+from fastapi import FastAPI, HTTPException, Response, Request, Query, File, UploadFile
 from fastapi.responses import PlainTextResponse, JSONResponse
 from pydantic import BaseModel
 from prometheus_client import generate_latest, CONTENT_TYPE_LATEST
 
+try:
+    from importlib.metadata import version
+    __version__ = version("artifactapi")
+except ImportError:
+    # Fallback for development when package isn't installed
+    __version__ = "dev"
+
 from .config import ConfigManager
 from .database import DatabaseManager
 from .storage import S3Storage
 from .cache import RedisCache
 from .metrics import MetricsManager
+from .docker_auth import get_docker_token_for_response
 
 
 class ArtifactRequest(BaseModel):
@@ -20,7 +30,14 @@ class ArtifactRequest(BaseModel):
     include_pattern: str
 
 
-app = FastAPI(title="Artifact Storage API", version="2.0.0")
+# Configure logging
+logging.basicConfig(
+    level=logging.INFO,
+    format='%(asctime)s - %(name)s - %(levelname)s - %(message)s'
+)
+logger = logging.getLogger(__name__)
+
+app = FastAPI(title="Artifact Storage API", version=__version__)
 
 # Initialize components using config
 config_path = os.environ.get("CONFIG_PATH")
@@ -45,7 +62,7 @@ def read_root():
     config._check_reload()
     return {
         "message": "Artifact Storage API",
-        "version": "2.0.0",
+        "version": app.version,
         "remotes": list(config.config.get("remotes", {}).keys()),
     }
 
@@ -55,6 +72,87 @@ def health_check():
     return {"status": "healthy"}
 
 
+@app.put("/cache/flush")
+def flush_cache(
+    remote: str = Query(default=None, description="Specific remote to flush (optional)"),
+    cache_type: str = Query(default="all", description="Type to flush: 'all', 'index', 'files', 'metrics'")
+):
+    """Flush cache entries for specified remote or all remotes"""
+    try:
+        result = {
+            "remote": remote,
+            "cache_type": cache_type,
+            "flushed": {
+                "redis_keys": 0,
+                "s3_objects": 0,
+                "operations": []
+            }
+        }
+
+        # Flush Redis entries based on cache_type
+        if cache_type in ["all", "index", "metrics"] and cache.available and cache.client:
+            patterns = []
+
+            if cache_type in ["all", "index"]:
+                if remote:
+                    patterns.append(f"index:{remote}:*")
+                else:
+                    patterns.append("index:*")
+
+            if cache_type in ["all", "metrics"]:
+                if remote:
+                    patterns.append(f"metrics:*:{remote}")
+                else:
+                    patterns.append("metrics:*")
+
+            for pattern in patterns:
+                keys = cache.client.keys(pattern)
+                if keys:
+                    cache.client.delete(*keys)
+                    result["flushed"]["redis_keys"] += len(keys)
+                    logger.info(f"Cache flush: Deleted {len(keys)} Redis keys matching '{pattern}'")
+
+            if result["flushed"]["redis_keys"] > 0:
+                result["flushed"]["operations"].append(f"Deleted {result['flushed']['redis_keys']} Redis keys")
+
+        # Flush S3 objects if requested
+        if cache_type in ["all", "files"]:
+            try:
+                # Use prefix filtering for remote-specific deletion
+                list_params = {"Bucket": storage.bucket}
+                if remote:
+                    list_params["Prefix"] = f"{remote}/"
+
+                response = storage.client.list_objects_v2(**list_params)
+                if 'Contents' in response:
+                    objects_to_delete = [obj['Key'] for obj in response['Contents']]
+
+                    for key in objects_to_delete:
+                        try:
+                            storage.client.delete_object(Bucket=storage.bucket, Key=key)
+                            result["flushed"]["s3_objects"] += 1
+                        except Exception as e:
+                            logger.warning(f"Failed to delete S3 object {key}: {e}")
+
+                    if objects_to_delete:
+                        scope = f" for remote '{remote}'" if remote else ""
+                        result["flushed"]["operations"].append(f"Deleted {len(objects_to_delete)} S3 objects{scope}")
+                        logger.info(f"Cache flush: Deleted {len(objects_to_delete)} S3 objects{scope}")
+
+            except Exception as e:
+                result["flushed"]["operations"].append(f"S3 flush failed: {str(e)}")
+                logger.error(f"Cache flush S3 error: {e}")
+
+        if not result["flushed"]["operations"]:
+            result["flushed"]["operations"].append("No cache entries found to flush")
+
+        return result
+
+    except Exception as e:
+        logger.error(f"Cache flush error: {e}")
+        raise HTTPException(status_code=500, detail=f"Cache flush failed: {str(e)}")
+
+
 async def construct_remote_url(remote_name: str, path: str) -> str:
     remote_config = config.get_remote_config(remote_name)
     if not remote_config:
@@ -68,6 +166,12 @@ async def construct_remote_url(remote_name: str, path: str) -> str:
             status_code=500, detail=f"No base_url configured for remote '{remote_name}'"
         )
 
+    # Handle Docker registry URLs
+    if remote_config.get("type") == "docker":
+        # Convert Docker paths to v2 API format
+        # e.g., library/nginx/manifests/latest -> v2/library/nginx/manifests/latest
+        return f"{base_url}/v2/{path}"
+
     return f"{base_url}/{path}"
 
 
@@ -98,13 +202,11 @@ async def check_artifact_patterns(
 
 
 async def cache_single_artifact(url: str, remote_name: str, path: str) -> dict:
-    # Check if using URL-based key or path-based key
-    if url.startswith("http"):
-        key = storage.get_object_key(url)
-    else:
-        key = storage.get_object_key_from_path(remote_name, path)
+    # Use hierarchical path-based key
+    key = storage.get_object_key(remote_name, path)
 
     if storage.exists(key):
+        logger.info(f"Cache ALREADY EXISTS: {url} (key: {key})")
         return {
             "url": url,
             "cached_url": storage.get_url(key),
@@ -112,12 +214,41 @@ async def cache_single_artifact(url: str, remote_name: str, path: str) -> dict:
         }
 
     try:
+        remote_config = config.get_remote_config(remote_name) or {}
+        is_docker = remote_config.get("type") == "docker" or "/v2/" in url
+
+        # Prepare headers for Docker registry requests
+        headers = {}
+        if is_docker:
+            if "/manifests/" in url:
+                headers["Accept"] = (
+                    "application/vnd.docker.distribution.manifest.v2+json,"
+                    "application/vnd.oci.image.manifest.v1+json,"
+                    "application/vnd.oci.image.index.v1+json,"
+                    "application/vnd.docker.distribution.manifest.list.v2+json"
+                )
+            elif "/blobs/" in url:
+                headers["Accept"] = "application/octet-stream"
+
         async with httpx.AsyncClient(follow_redirects=True) as client:
-            response = await client.get(url)
+            response = await client.get(url, headers=headers)
+
+            # Handle Docker Bearer token challenge
+            if response.status_code == 401 and is_docker:
+                www_auth = response.headers.get("WWW-Authenticate", "")
+                username = remote_config.get("username")
+                password = remote_config.get("password")
+                token = await get_docker_token_for_response(www_auth, username, password)
+                if token:
+                    headers["Authorization"] = f"Bearer {token}"
+                    response = await client.get(url, headers=headers)
+
             response.raise_for_status()
 
             storage_path = storage.upload(key, response.content)
 
+            logger.info(f"Cache ADD SUCCESS: {url} (size: {len(response.content)} bytes, key: {key})")
+
             return {
                 "url": url,
                 "cached_url": storage.get_url(key),
@@ -173,6 +304,7 @@ async def get_artifact(remote_name: str, path: str):
 
     # Check if artifact matches configured patterns
     if not await check_artifact_patterns(remote_name, repo_path, file_path, path):
+        logger.info(f"PATTERN BLOCKED: {remote_name}/{path} - not matching include patterns")
         raise HTTPException(
             status_code=403, detail="Artifact not allowed by configuration patterns"
         )
@@ -180,24 +312,20 @@ async def get_artifact(remote_name: str, path: str):
     # Construct the remote URL
     remote_url = await construct_remote_url(remote_name, path)
 
-    # Check if artifact is already cached (try both URL and path-based keys)
-    url_key = storage.get_object_key(remote_url)
-    path_key = storage.get_object_key_from_path(remote_name, path)
-
-    cached_key = None
-    if storage.exists(url_key):
-        cached_key = url_key
-    elif storage.exists(path_key):
-        cached_key = path_key
+    # Check if artifact is already cached
+    cached_key = storage.get_object_key(remote_name, path)
+    if not storage.exists(cached_key):
+        cached_key = None
 
     # For index files, check Redis TTL validity
     filename = os.path.basename(path)
-    is_index = cache.is_index_file(filename)
+    is_index = cache.is_index_file(path)  # Check full path, not just filename
 
     if cached_key and is_index:
         # Index file exists, but check if it's still valid
         if not cache.is_index_valid(remote_name, path):
             # Index has expired, remove it from S3
+            logger.info(f"Index EXPIRED: {remote_name}/{path} - removing from cache")
             cache.cleanup_expired_index(storage, remote_name, path)
             cached_key = None  # Force re-download
 
@@ -207,6 +335,9 @@ async def get_artifact(remote_name: str, path: str):
             artifact_data = storage.download_object(cached_key)
             filename = os.path.basename(path)
 
+            # Log cache hit
+            logger.info(f"Cache HIT: {remote_name}/{path} (size: {len(artifact_data)} bytes, key: {cached_key})")
+
             # Determine content type based on file extension
             content_type = "application/octet-stream"
             if filename.endswith(".tar.gz"):
@@ -245,9 +376,11 @@ async def get_artifact(remote_name: str, path: str):
             )
 
     # Artifact not cached, cache it first
+    logger.info(f"Cache MISS: {remote_name}/{path} - fetching from remote: {remote_url}")
     result = await cache_single_artifact(remote_url, remote_name, path)
 
     if result["status"] == "error":
+        logger.error(f"Cache ADD FAILED: {remote_name}/{path} - {result['error']}")
         raise HTTPException(
             status_code=502, detail=f"Failed to fetch artifact: {result['error']}"
         )
@@ -258,10 +391,11 @@ async def get_artifact(remote_name: str, path: str):
         cache_config = config.get_cache_config(remote_name)
         index_ttl = cache_config.get("index_ttl", 300)  # Default 5 minutes
         cache.mark_index_cached(remote_name, path, index_ttl)
+        logger.info(f"Index file cached with TTL: {remote_name}/{path} (ttl: {index_ttl}s)")
 
     # Now return the cached artifact
     try:
-        cache_key = storage.get_object_key(remote_url)
+        cache_key = storage.get_object_key(remote_name, path)
         artifact_data = storage.download_object(cache_key)
         filename = os.path.basename(path)
 
@@ -283,7 +417,7 @@ async def get_artifact(remote_name: str, path: str):
         metrics.record_cache_miss(remote_name, len(artifact_data))
 
         # Record artifact mapping in database
-        cache_key = storage.get_object_key(remote_url)
+        cache_key = storage.get_object_key(remote_name, path)
         database.record_artifact_mapping(
             cache_key, remote_name, path, len(artifact_data)
         )
@@ -301,6 +435,79 @@ async def get_artifact(remote_name: str, path: str):
         raise HTTPException(status_code=500, detail=f"Error serving artifact: {str(e)}")
 
 
+@app.get("/v2/")
+async def docker_v2_ping():
+    return Response(
+        content="{}",
+        media_type="application/json",
+        headers={"Docker-Distribution-Api-Version": "registry/2.0"},
+    )
+
+
+@app.api_route("/v2/{remote_name}/{path:path}", methods=["GET", "HEAD"])
+async def docker_v2_proxy(request: Request, remote_name: str, path: str):
+    remote_config = config.get_remote_config(remote_name)
+    if not remote_config:
+        raise HTTPException(status_code=404, detail=f"Remote '{remote_name}' not configured")
+    if remote_config.get("type") != "docker":
+        raise HTTPException(status_code=400, detail=f"Remote '{remote_name}' is not a docker remote")
+
+    remote_url = await construct_remote_url(remote_name, path)
+
+    cached_key = storage.get_object_key(remote_name, path)
+    if not storage.exists(cached_key):
+        cached_key = None
+
+    is_index = cache.is_index_file(path)
+
+    if cached_key and is_index:
+        if not cache.is_index_valid(remote_name, path):
+            logger.info(f"Index EXPIRED: {remote_name}/{path} - removing from cache")
+            cache.cleanup_expired_index(storage, remote_name, path)
+            cached_key = None
+
+    if not cached_key:
+        logger.info(f"Cache MISS: {remote_name}/{path} - fetching from remote: {remote_url}")
+        result = await cache_single_artifact(remote_url, remote_name, path)
+        if result["status"] == "error":
+            raise HTTPException(status_code=502, detail=f"Failed to fetch: {result['error']}")
+        if result["status"] == "cached" and is_index:
+            cache_config = config.get_cache_config(remote_name)
+            index_ttl = cache_config.get("index_ttl", 300)
+            cache.mark_index_cached(remote_name, path, index_ttl)
+            logger.info(f"Index file cached with TTL: {remote_name}/{path} (ttl: {index_ttl}s)")
+
+    artifact_data = storage.download_object(storage.get_object_key(remote_name, path))
+
+    is_blob = "/blobs/" in path
+    if is_blob:
+        content_type = "application/octet-stream"
+    else:
+        try:
+            manifest_json = json.loads(artifact_data)
+            content_type = manifest_json.get("mediaType")
+            if not content_type:
+                if "manifests" in manifest_json:
+                    content_type = "application/vnd.oci.image.index.v1+json"
+                else:
+                    content_type = "application/vnd.oci.image.manifest.v1+json"
+        except Exception:
+            content_type = "application/vnd.oci.image.manifest.v1+json"
+
+    digest = f"sha256:{hashlib.sha256(artifact_data).hexdigest()}"
+    headers = {
+        "Docker-Distribution-Api-Version": "registry/2.0",
+        "Docker-Content-Digest": digest,
+        "Content-Length": str(len(artifact_data)),
+    }
+
+    if request.method == "HEAD":
+        return Response(status_code=200, headers=headers, media_type=content_type)
+
+    metrics.record_cache_hit(remote_name, len(artifact_data))
+    return Response(content=artifact_data, media_type=content_type, headers=headers)
+
+
 async def discover_artifacts(remote: str, include_pattern: str) -> list[str]:
     if "github.com" in remote:
         return await discover_github_releases(remote, include_pattern)
@@ -531,7 +738,11 @@ async def list_cached_artifacts(
 
         cached_artifacts = []
         for url in matching_urls:
-            key = storage.get_object_key(url)
+            # Extract path from URL for hierarchical key generation
+            from urllib.parse import urlparse
+            parsed = urlparse(url)
+            path = parsed.path
+            key = storage.get_object_key(remote, path)
             if storage.exists(key):
                 cached_artifacts.append(
                     {"url": url, "cached_url": storage.get_url(key), "key": key}

src/artifactapi/storage.py

@@ -1,6 +1,5 @@
 import os
 import hashlib
-from urllib.parse import urlparse
 import boto3
 from botocore.config import Config
 from botocore.exceptions import ClientError
@@ -55,17 +54,27 @@ class S3Storage:
         except ClientError:
             self.client.create_bucket(Bucket=self.bucket)
 
-    def get_object_key(self, url: str) -> str:
-        url_hash = hashlib.sha256(url.encode()).hexdigest()[:16]
-        parsed = urlparse(url)
-        filename = os.path.basename(parsed.path)
-        return f"{parsed.netloc}/{url_hash}/{filename}"
+    def get_object_key(self, remote_name: str, path: str) -> str:
+        # Extract directory path and filename
+        clean_path = path.lstrip('/')
+        filename = os.path.basename(clean_path)
+        directory_path = os.path.dirname(clean_path)
 
-    def get_object_key_from_path(self, remote_name: str, path: str) -> str:
-        # Create a key based on the API path for direct access
-        path_hash = hashlib.sha256(path.encode()).hexdigest()[:16]
-        filename = os.path.basename(path)
-        return f"{remote_name}/{path_hash}/{filename}"
+        # Special handling for Docker registry blobs (use digest as key for deduplication)
+        if "/blobs/sha256:" in clean_path:
+            # Extract the SHA256 digest for Docker blobs
+            parts = clean_path.split("/blobs/sha256:")
+            if len(parts) == 2:
+                digest = parts[1]
+                return f"{remote_name}/blobs/sha256/{digest}"
+
+        # Hash the directory path to keep keys manageable while preserving remote structure
+        if directory_path:
+            path_hash = hashlib.sha256(directory_path.encode()).hexdigest()[:16]
+            return f"{remote_name}/{path_hash}/{filename}"
+        else:
+            # If no directory, just use remote and filename
+            return f"{remote_name}/{filename}"
 
     def exists(self, key: str) -> bool:
         try: