Added Locks to each endpoint; Added new busy endpoint; Removed some u…

…nused imports

webapp/blueprints/meta.py

@@ -2,7 +2,7 @@
 from fastapi import APIRouter
 import h5py
 import os
-from ..utils import NumpySafeJSONResponse
+from ..utils import NumpySafeJSONResponse, LOCK
 
 router = APIRouter()
 
@@ -16,20 +16,21 @@ def get_meta(path: str, subpath: str = "/"):
     Returns:
         template: A rendered Jinja2 HTML template
     """
+    with LOCK:
+        try:
 
-    path = "/" + path
+            path = "/" + path
 
-    try:
-        with h5py.File(path, "r", swmr=SWMR_DEFAULT, libver="latest") as file:
-            if subpath:
-                meta = NumpySafeJSONResponse(metadata(file[subpath]))
-            else:
-                meta = NumpySafeJSONResponse(metadata(file["/"]))
-            return meta
+            with h5py.File(path, "r", swmr=SWMR_DEFAULT, libver="latest") as file:
+                if subpath:
+                    meta = NumpySafeJSONResponse(metadata(file[subpath]))
+                else:
+                    meta = NumpySafeJSONResponse(metadata(file["/"]))
+                return meta
 
-    except Exception as e:
-        print(e)
-        # print(f"File {file} can not be opened yet.")
+        except Exception as e:
+            print(e)
+            # print(f"File {file} can not be opened yet.")
 
 
 def metadata(node: h5py.HLObject) -> Mapping[str, Any]:

webapp/blueprints/search.py

@@ -1,8 +1,8 @@
-from ast import Num
+import time
 from fastapi import APIRouter
 import h5py
 import os
-from ..utils import NumpySafeJSONResponse
+from ..utils import NumpySafeJSONResponse, LOCK
 
 router = APIRouter()
 
@@ -16,19 +16,20 @@ def get_nodes(path: str, subpath: str = "/"):
     Returns:
         template: A rendered Jinja2 HTML template
     """
-    path = "/" + path
+    with LOCK:
 
-    try:
+        path = "/" + path
 
-        with h5py.File(path, "r", swmr=SWMR_DEFAULT, libver="latest") as file:
-            if subpath:
-                nodes = NumpySafeJSONResponse(search(file[subpath]))
-            else:
-                nodes = NumpySafeJSONResponse(search(file["/"]))
-            return nodes
+        try:
+            with h5py.File(path, "r", swmr=SWMR_DEFAULT, libver="latest") as file:
+                if subpath:
+                    nodes = NumpySafeJSONResponse(search(file[subpath]))
+                else:
+                    nodes = NumpySafeJSONResponse(search(file["/"]))
+                return nodes
 
-    except:
-        print(f"File {file} can not be opened yet.")
+        except:
+            print(f"File {file} can not be opened yet.")
 
 
 def search(node):

webapp/blueprints/slice.py

@@ -2,7 +2,7 @@
 import os
 import re
 from fastapi import APIRouter
-from ..utils import safe_json_dump
+from ..utils import safe_json_dump, LOCK
 
 router = APIRouter()
 
@@ -16,36 +16,36 @@ def get_slice(path: str, subpath: str = "/", slice: str = None):
     Returns:
         template: A rendered Jinja2 HTML template
     """
-
-    path = "/" + path
-
-    if slice is not None:
-        slices = re.search("(\d+):(\d+):(\d+)", slice)
-        if slice:
-            slice_start = int(slices[1])
-            slice_stop = int(slices[2])
-            slice_step = int(slices[3])
+    with LOCK:
+        path = "/" + path
+
+        if slice is not None:
+            slices = re.search("(\d+):(\d+):(\d+)", slice)
+            if slice:
+                slice_start = int(slices[1])
+                slice_stop = int(slices[2])
+                slice_step = int(slices[3])
+            else:
+                print("Defaulting to 'all'.")
+                slice_start = 0
+                slice_stop = 0
+                slice_step = 0
         else:
-            print("Defaulting to 'all'.")
-            slice_start = 0
-            slice_stop = 0
-            slice_step = 0
-    else:
-        return "Please enter a valid url, e.g. \
-            '/slice/<path>?subpath=<subpath>?slice=<slice>'"
-
-    try:
-        with h5py.File(path, "r", swmr=SWMR_DEFAULT, libver="latest") as file:
-            try:
-                if subpath and isinstance(file[subpath], h5py.Dataset):
-                    sliced = file[subpath][slice_start:slice_stop:slice_step]
-                    return safe_json_dump(sliced)
-                else:
-                    # meta = metadata(file["/"])
-                    print("Path not valid or not a dataset.")
-                # return meta
-            except Exception as e:
-                print(e)
-
-    except:
-        print(f"File {file} can not be opened yet.")
+            return "Please enter a valid url, e.g. \
+                '/slice/<path>?subpath=<subpath>?slice=<slice>'"
+
+        try:
+            with h5py.File(path, "r", swmr=SWMR_DEFAULT, libver="latest") as file:
+                try:
+                    if subpath and isinstance(file[subpath], h5py.Dataset):
+                        sliced = file[subpath][slice_start:slice_stop:slice_step]
+                        return safe_json_dump(sliced)
+                    else:
+                        # meta = metadata(file["/"])
+                        print("Path not valid or not a dataset.")
+                    # return meta
+                except Exception as e:
+                    print(e)
+
+        except:
+            print(f"File {file} can not be opened yet.")

webapp/blueprints/tree.py

@@ -1,12 +1,11 @@
 from collections import defaultdict
 import os
 from typing import Any, Dict, List, Union
-import numpy
 import h5py
 from fastapi import APIRouter
 
 from webapp.blueprints.meta import metadata
-from webapp.utils import NumpySafeJSONResponse
+from webapp.utils import NumpySafeJSONResponse, LOCK
 
 SWMR_DEFAULT = bool(int(os.getenv("HDF5_SWMR_DEFAULT", "1")))
 
@@ -20,25 +19,25 @@ def show_tree(path: str, subpath: str = "/"):
     Returns:
         template: A rendered Jinja2 HTML template
     """
-
-    path = "/" + path
-
-    tr = defaultdict(dict)
-
-    def visit_node(addr: Union[str, List[str]], node: h5py.HLObject, tree: Dict[str, Any] = tr) -> None:
-        if isinstance(addr, str):
-            return visit_node(addr.split("/"), node)
-        elif len(addr) > 1:
-            return visit_node(addr[1:], node, tree[addr[0]]["subnodes"])
-        else:
-            tree[addr[0]] = {
-                "subnodes": defaultdict(dict),
-                "metadata": metadata(node)
-            }
-
-    try:
-        with h5py.File(path, "r", swmr=SWMR_DEFAULT, libver="latest") as file:
-            file.visititems(visit_node)
-        return NumpySafeJSONResponse(tr)
-    except Exception as e:
-        return e
+    with LOCK:
+        path = "/" + path
+
+        tr = defaultdict(dict)
+
+        def visit_node(addr: Union[str, List[str]], node: h5py.HLObject, tree: Dict[str, Any] = tr) -> None:
+            if isinstance(addr, str):
+                return visit_node(addr.split("/"), node)
+            elif len(addr) > 1:
+                return visit_node(addr[1:], node, tree[addr[0]]["subnodes"])
+            else:
+                tree[addr[0]] = {
+                    "subnodes": defaultdict(dict),
+                    "metadata": metadata(node)
+                }
+
+        try:
+            with h5py.File(path, "r", swmr=SWMR_DEFAULT, libver="latest") as file:
+                file.visititems(visit_node)
+            return NumpySafeJSONResponse(tr)
+        except Exception as e:
+            return e

webapp/main.py

@@ -1,7 +1,7 @@
 import os
-from markupsafe import escape
+from .utils import LOCK
 
-from fastapi import FastAPI
+from fastapi import FastAPI, Response, status
 
 # Setup the app
 app = FastAPI(root_path=os.path.abspath(os.path.dirname(__file__)))
@@ -20,3 +20,10 @@
 @app.get("/")
 def index():
     return {"INFO": "Please provide a path to the HDF5 file, e.g. '/file/<path>'."}
+
+
+@app.get("/busy")
+def busy(response: Response):
+    if LOCK.locked():
+        response.status_code = status.HTTP_423_LOCKED
+    return {"busy": LOCK.locked()}

webapp/utils.py

@@ -1,7 +1,10 @@
+import threading
 import sys
 from typing import Any
 from starlette.responses import JSONResponse
 
+LOCK = threading.Lock()
+
 def safe_json_dump(content):
     """
     Try to use native orjson path; fall back to going through Python list.