fix(node.http): avoid exhausting ephemeral ports in backfill logic

README.md

@@ -84,7 +84,7 @@ B <--> D["Database<br/>(SQLite)"]
 
 2. Run the block explorer:
    ```bash
-   uv run python -m main
+   PYTHONPATH=src uv run python -m main
    ```
 By default, this will try to connect to a local Node running on port 18080.
 
@@ -95,7 +95,7 @@ By default, this will try to connect to a local Node running on port 18080.
 
 - If you want to run the Explorer without a Node, make sure to set the `NBE_NODE_API` environment variable to `fake`:
     1. ```bash
-       NBE_NODE_API=fake uv run python -m main
+       PYTHONPATH=src NBE_NODE_API=fake uv run python -m main
        ```
     2. ```bash
        docker run -e NBE_NODE_API=fake -p 8000:8000 nomos-block-explorer

src/node/api/http.py

@@ -78,25 +78,22 @@ class HttpNodeApi(NodeApi):
 
     async def get_block_by_hash(self, block_hash: str) -> Optional[BlockSerializer]:
         url = urljoin(self.base_url, self.ENDPOINT_BLOCK_BY_HASH)
-        response = requests.post(
-            url,
-            auth=self.authentication,
-            timeout=60,
-            json=block_hash,
-        )
-        if response.status_code == 404:
-            return None
-        response.raise_for_status()
-        json_data = response.json()
-        if json_data is None:
-            logger.warning(f"Block {block_hash} returned null from API")
-            return None
-        block = BlockSerializer.model_validate(json_data)
-        # The storage endpoint doesn't include the block hash in the response,
-        # so we set it from the request body
-        if not block.header.hash:
-            block.header.hash = bytes.fromhex(block_hash)
-        return block
+        auth = self.authentication.map(lambda _auth: _auth.for_httpx()).unwrap_or(None)
+        async with httpx.AsyncClient(timeout=60, auth=auth) as client:
+            response = await client.post(url, json=block_hash)
+            if response.status_code == 404:
+                return None
+            response.raise_for_status()
+            json_data = response.json()
+            if json_data is None:
+                logger.warning(f"Block {block_hash} returned null from API")
+                return None
+            block = BlockSerializer.model_validate(json_data)
+            # The storage endpoint doesn't include the block hash in the response,
+            # so we set it from the request body
+            if not block.header.hash:
+                block.header.hash = bytes.fromhex(block_hash)
+            return block
 
     async def get_blocks_stream(self) -> AsyncIterator[BlockSerializer]:
         url = urljoin(self.base_url, self.ENDPOINT_BLOCKS_STREAM)

src/node/lifespan.py

@@ -31,6 +31,7 @@ async def backfill_to_lib(app: "NBE") -> None:
             info = await app.state.node_api.get_info()
             logger.info(f"Node info: LIB={info.lib}, tip={info.tip}, slot={info.slot}, height={info.height}")
 
+            logger.debug(f"Block {info.lib}...")
             await backfill_chain_from_hash(app, info.lib)
             return
 
@@ -51,6 +52,7 @@ async def backfill_chain_from_hash(app: "NBE", block_hash: str) -> None:
 
     while True:
         # Check if we already have this block
+        logger.debug(f"Block {current_hash}...")
         existing = await app.state.block_repository.get_by_hash(bytes.fromhex(current_hash))
         if existing.is_some:
             logger.debug(f"Block {current_hash[:16]}... already exists, stopping chain walk")