Hot reload

.pylintrc37

@@ -146,7 +146,8 @@ disable=invalid-name,
         no-else-return,
         useless-object-inheritance,
         possibly-unused-variable,
-        too-many-lines
+        too-many-lines,
+        too-many-statements
 
 # Enable the message, report, category or checker with the given id(s). You can
 # either give multiple identifier separated by comma (,) or put this option

CHANGELOG.md

@@ -1,3 +1,8 @@
+## 0.30.0 - 2018-11-14
+## Added
+- Hot reload from the browser [#362](https://github.com/plotly/dash/pull/362)
+- Silence routes logging with `dev_tools_silence_routes_logging`.
+
 ## 0.29.0 - 2018-11-06
 ## Added
 - Added component namespaces registry, collect the resources needed by component library when they are imported instead of crawling the layout. [#444](https://github.com/plotly/dash/pull/444)

dash/_configs.py

@@ -22,7 +22,12 @@ def env_configs():
         'DASH_COMPONENTS_CACHE_MAX_AGE',
         'DASH_INCLUDE_ASSETS_FILES',
         'DASH_SERVE_DEV_BUNDLES',
-        'DASH_DEBUG'
+        'DASH_DEBUG',
+        'DASH_HOT_RELOAD',
+        'DASH_HOT_RELOAD_INTERVAL',
+        'DASH_HOT_RELOAD_WATCH_INTERVAL',
+        'DASH_HOT_RELOAD_MAX_RETRY',
+        'DASH_SILENCE_ROUTES_LOGGING'
     )})
 
 

dash/_utils.py

@@ -1,3 +1,6 @@
+import uuid
+
+
 def interpolate_str(template, **data):
     s = template
     for k, v in data.items():
@@ -20,12 +23,15 @@ def format_tag(tag_name, attributes, inner='', closed=False, opened=False):
             '{}="{}"'.format(k, v) for k, v in attributes.items()]))
 
 
+def generate_hash():
+    return str(uuid.uuid4().hex).strip('-')
+
+
 def get_asset_path(
         requests_pathname,
         routes_pathname,
         asset_path,
         asset_url_path):
-
     i = requests_pathname.rfind(routes_pathname)
     req = requests_pathname[:i]
 

dash/_watch.py

@@ -0,0 +1,36 @@
+import collections
+import os
+import re
+import time
+
+
+def watch(folders, on_change, pattern=None, sleep_time=0.1):
+    pattern = re.compile(pattern) if pattern else None
+    watched = collections.defaultdict(lambda: -1)
+
+    def walk():
+        walked = []
+        for folder in folders:
+            for current, _, files, in os.walk(folder):
+                for f in files:
+                    if pattern and not pattern.search(f):
+                        continue
+                    path = os.path.join(current, f)
+
+                    info = os.stat(path)
+                    new_time = info.st_mtime
+
+                    if new_time > watched[path] > 0:
+                        on_change(path, new_time, False)
+
+                    watched[path] = new_time
+                    walked.append(path)
+
+        # Look for deleted files
+        for w in [x for x in watched.keys() if x not in walked]:
+            del watched[w]
+            on_change(w, -1, True)
+
+    while True:
+        walk()
+        time.sleep(sleep_time)