dummy

README.md

@@ -634,3 +634,5 @@ The system uses a precise naming convention:
   - Ensures fair resource allocation among all clients
 
 - **Examples**: Implementation examples are available in the [examples/rate_limit](examples/rate_limit) directory.
+
+dummy

stac_fastapi/core/setup.py

@@ -19,6 +19,7 @@
     "pygeofilter~=0.3.1",
     "jsonschema~=4.0.0",
     "slowapi~=0.1.9",
+    "redis==6.4.0",
 ]
 
 setup(

stac_fastapi/core/stac_fastapi/core/core.py

@@ -24,6 +24,12 @@
 from stac_fastapi.core.base_settings import ApiBaseSettings
 from stac_fastapi.core.datetime_utils import format_datetime_range
 from stac_fastapi.core.models.links import PagingLinks
+from stac_fastapi.core.redis_utils import (
+    add_previous_link,
+    cache_current_url,
+    cache_previous_url,
+    connect_redis,
+)
 from stac_fastapi.core.serializers import CollectionSerializer, ItemSerializer
 from stac_fastapi.core.session import Session
 from stac_fastapi.core.utilities import filter_fields
@@ -237,6 +243,12 @@ async def all_collections(self, **kwargs) -> stac_types.Collections:
         base_url = str(request.base_url)
         limit = int(request.query_params.get("limit", os.getenv("STAC_ITEM_LIMIT", 10)))
         token = request.query_params.get("token")
+        current_url = str(request.url)
+        redis = None
+        try:
+            redis = await connect_redis()
+        except Exception:
+            redis = None
 
         collections, next_token = await self.database.get_all_collections(
             token=token, limit=limit, request=request
@@ -252,6 +264,10 @@ async def all_collections(self, **kwargs) -> stac_types.Collections:
             },
         ]
 
+        await add_previous_link(redis, links, "collections", current_url, token)
+        if redis:
+            await cache_previous_url(redis, current_url, "collections")
+
         if next_token:
             next_link = PagingLinks(next=next_token, request=request).link_next()
             links.append(next_link)
@@ -284,7 +300,6 @@ async def get_collection(
     async def item_collection(
         self,
         collection_id: str,
-        request: Request,
         bbox: Optional[BBox] = None,
         datetime: Optional[str] = None,
         limit: Optional[int] = None,
@@ -323,6 +338,31 @@ async def item_collection(
         Raises:
             HTTPException: 404 if the collection does not exist.
         """
+        request: Request = kwargs["request"]
+        token = request.query_params.get("token")
+        base_url = str(request.base_url)
+
+        current_url = str(request.url)
+
+        try:
+            redis = await connect_redis()
+        except Exception:
+            redis = None
+
+        if redis:
+            await cache_current_url(redis, current_url, collection_id)
+
+        collection = await self.get_collection(
+            collection_id=collection_id, request=request
+        )
+        collection_id = collection.get("id")
+        if collection_id is None:
+            raise HTTPException(status_code=404, detail="Collection not found")
+
+        search = self.database.make_search()
+        search = self.database.apply_collections_filter(
+            search=search, collection_ids=[collection_id]
+        )
         try:
             await self.get_collection(collection_id=collection_id, request=request)
         except Exception:
@@ -336,6 +376,45 @@ async def item_collection(
             datetime=datetime,
             limit=limit,
             token=token,
+            collection_ids=[collection_id],
+            datetime_search=datetime_search,
+        )
+
+        items = [
+            self.item_serializer.db_to_stac(item, base_url=base_url) for item in items
+        ]
+
+        collection_links = [
+            {
+                "rel": "collection",
+                "type": "application/json",
+                "href": urljoin(str(request.base_url), f"collections/{collection_id}"),
+            },
+            {
+                "rel": "parent",
+                "type": "application/json",
+                "href": urljoin(str(request.base_url), f"collections/{collection_id}"),
+            },
+        ]
+
+        paging_links = await PagingLinks(request=request, next=next_token).get_links()
+
+        if redis:
+            await add_previous_link(
+                redis, paging_links, collection_id, current_url, token
+            )
+
+        if redis:
+            await cache_previous_url(redis, current_url, collection_id)
+
+        links = collection_links + paging_links
+
+        return stac_types.ItemCollection(
+            type="FeatureCollection",
+            features=items,
+            links=links,
+            numReturned=len(items),
+            numMatched=maybe_count,
             sortby=sortby,
             query=query,
             filter_expr=filter_expr,
@@ -482,7 +561,14 @@ async def post_search(
             HTTPException: If there is an error with the cql2_json filter.
         """
         base_url = str(request.base_url)
+        current_url = str(request.url)
+        try:
+            redis = await connect_redis()
+        except Exception:
+            redis = None
 
+        if redis:
+            await cache_current_url(redis, current_url, "search_result")
         search = self.database.make_search()
 
         if search_request.ids:
@@ -592,6 +678,14 @@ async def post_search(
         ]
         links = await PagingLinks(request=request, next=next_token).get_links()
 
+        if redis:
+            await add_previous_link(
+                redis, links, "search_result", current_url, search_request.token
+            )
+
+        if redis:
+            await cache_previous_url(redis, current_url, "search_result")
+
         return stac_types.ItemCollection(
             type="FeatureCollection",
             features=items,

stac_fastapi/core/stac_fastapi/core/redis_utils.py

@@ -0,0 +1,196 @@
+"""Utilities for connecting to and managing Redis connections."""
+
+import logging
+import os
+from typing import Dict, List, Optional
+
+from pydantic_settings import BaseSettings
+from redis import asyncio as aioredis
+from stac_pydantic.shared import MimeTypes
+
+from stac_fastapi.core.utilities import get_bool_env
+
+redis_pool = None
+
+logger = logging.getLogger(__name__)
+
+
+class RedisSentinelSettings(BaseSettings):
+    """Configuration settings for connecting to a Redis Sentinel server."""
+
+    sentinel_hosts: List[str] = os.getenv("REDIS_SENTINEL_HOSTS", "").split(",")
+    sentinel_ports: List[int] = [
+        int(port)
+        for port in os.getenv("REDIS_SENTINEL_PORTS", "").split(",")
+        if port.strip()
+    ]
+    sentinel_master_name: str = os.getenv("REDIS_SENTINEL_MASTER_NAME", "")
+    redis_db: int = int(os.getenv("REDIS_DB", "0"))
+
+    max_connections: int = int(os.getenv("REDIS_MAX_CONNECTIONS", "5"))
+    retry_on_timeout: bool = get_bool_env("REDIS_RETRY_TIMEOUT", True)
+    decode_responses: bool = get_bool_env("REDIS_DECODE_RESPONSES", True)
+    client_name: str = os.getenv("REDIS_CLIENT_NAME", "stac-fastapi-app")
+    health_check_interval: int = int(os.getenv("REDIS_HEALTH_CHECK_INTERVAL", "30"))
+
+
+class RedisSettings(BaseSettings):
+    """Configuration settings for connecting to a Redis server."""
+
+    redis_host: str = os.getenv("REDIS_HOST", "localhost")
+    redis_port: int = int(os.getenv("REDIS_PORT", "6379"))
+    redis_db: int = int(os.getenv("REDIS_DB", "0"))
+
+    max_connections: int = int(os.getenv("REDIS_MAX_CONNECTIONS", "5"))
+    retry_on_timeout: bool = get_bool_env("REDIS_RETRY_TIMEOUT", True)
+    decode_responses: bool = get_bool_env("REDIS_DECODE_RESPONSES", True)
+    client_name: str = os.getenv("REDIS_CLIENT_NAME", "stac-fastapi-app")
+    health_check_interval: int = int(os.getenv("REDIS_HEALTH_CHECK_INTERVAL", "30"))
+
+
+# select which configuration to be used RedisSettings or RedisSentinelSettings
+redis_settings = RedisSettings()
+
+
+async def connect_redis_sentinel(
+    settings: Optional[RedisSentinelSettings] = None,
+) -> Optional[aioredis.Redis]:
+    """Return a Redis Sentinel connection."""
+    global redis_pool
+    settings = redis_settings
+
+    if (
+        not settings.sentinel_hosts
+        or not settings.sentinel_hosts[0]
+        or not settings.sentinel_master_name
+    ):
+        return None
+
+    if redis_pool is None:
+        try:
+            sentinel = aioredis.Sentinel(
+                [
+                    (host, port)
+                    for host, port in zip(
+                        settings.sentinel_hosts, settings.sentinel_ports
+                    )
+                ],
+                decode_responses=settings.decode_responses,
+                retry_on_timeout=settings.retry_on_timeout,
+                client_name=f"{settings.client_name}-sentinel",
+            )
+
+            master = sentinel.master_for(
+                settings.sentinel_master_name,
+                db=settings.redis_db,
+                decode_responses=settings.decode_responses,
+                retry_on_timeout=settings.retry_on_timeout,
+                client_name=settings.client_name,
+                max_connections=settings.max_connections,
+            )
+
+            redis_pool = master
+
+        except Exception:
+            return None
+
+    return redis_pool
+
+
+async def connect_redis(
+    settings: Optional[RedisSettings] = None,
+) -> Optional[aioredis.Redis]:
+    """Return a Redis connection for regular Redis server."""
+    global redis_pool
+    settings = redis_settings
+
+    if not settings.redis_host:
+        return None
+
+    if redis_pool is None:
+        try:
+            redis_pool = aioredis.Redis(
+                host=settings.redis_host,
+                port=settings.redis_port,
+                db=settings.redis_db,
+                decode_responses=settings.decode_responses,
+                retry_on_timeout=settings.retry_on_timeout,
+                client_name=settings.client_name,
+                health_check_interval=settings.health_check_interval,
+                max_connections=settings.max_connections,
+            )
+        except Exception as e:
+            logger.error(f"Redis connection failed: {e}")
+            return None
+
+    return redis_pool
+
+
+async def close_redis() -> None:
+    """Close the Redis connection pool if it exists."""
+    global redis_pool
+    if redis_pool:
+        await redis_pool.close()
+        redis_pool = None
+
+
+async def cache_current_url(redis, current_url: str, key: str) -> None:
+    """Add to Redis cache the current URL for navigation."""
+    if not redis:
+        return
+
+    try:
+        current_key = f"current:{key}"
+        await redis.setex(current_key, 600, current_url)
+    except Exception as e:
+        logger.error(f"Redis cache error for {key}: {e}")
+
+
+async def get_previous_url(redis, key: str) -> Optional[str]:
+    """Get previous URL from Redis cache if it exists."""
+    if redis is None:
+        return None
+
+    try:
+        prev_key = f"prev:{key}"
+        previous_url = await redis.get(prev_key)
+        if previous_url:
+            return previous_url
+    except Exception as e:
+        logger.error(f"Redis get previous error for {key}: {e}")
+
+    return None
+
+
+async def cache_previous_url(redis, current_url: str, key: str) -> None:
+    """Cache the current URL as previous for previous links in next page."""
+    if not redis:
+        return
+
+    try:
+        prev_key = f"prev:{key}"
+        await redis.setex(prev_key, 600, current_url)
+    except Exception as e:
+        logger.error(f"Redis cache previous error for {key}: {e}")
+
+
+async def add_previous_link(
+    redis,
+    links: List[Dict],
+    key: str,
+    current_url: str,
+    token: Optional[str] = None,
+) -> None:
+    """Add previous link into navigation."""
+    if not redis or not token:
+        return
+
+    previous_url = await get_previous_url(redis, key)
+    if previous_url:
+        links.append(
+            {
+                "rel": "previous",
+                "type": MimeTypes.json,
+                "href": previous_url,
+            }
+        )

stac_fastapi/tests/conftest.py

@@ -6,6 +6,7 @@
 
 import pytest
 import pytest_asyncio
+import redis  # noqa: F401
 from fastapi import Depends, HTTPException, security, status
 from httpx import ASGITransport, AsyncClient
 from pydantic import ConfigDict