wip stac reader

aiocogeo/stac.py

@@ -0,0 +1,41 @@
+import asyncio
+from dataclasses import dataclass
+from typing import List
+from urllib.parse import urlsplit
+
+import aiohttp
+
+from .cog import COGReader
+
+
+@dataclass
+class STACReader:
+    filepath: str
+    readers: List[COGReader] = None
+
+    async def __aenter__(self):
+        splits = urlsplit(self.filepath)
+        if splits.scheme in {"http", "https"}:
+            async with aiohttp.ClientSession() as session:
+                async with session.get(self.filepath) as resp:
+                    resp.raise_for_status()
+                    item = await resp.json()
+        else:
+            # TODO: support s3
+            pass
+
+        reader_futs = []
+        for asset in item["assets"]:
+            if item["assets"][asset]["type"] == "image/x.geotiff":
+                reader = COGReader(item["assets"][asset]["href"]).__aenter__()
+                reader_futs.append(reader)
+        self.readers = await asyncio.gather(*reader_futs)
+        return self
+
+    async def __aexit__(self, exc_type, exc_val, exc_tb):
+        for reader in self.readers:
+            await reader._file_reader._close()
+
+    async def get_tile(self, x: int, y: int, z: int):
+        futs = [reader.get_tile(x, y, z) for reader in self.readers]
+        return await asyncio.gather(*futs)