added missing devserver.py m(

blag/devserver.py

@@ -0,0 +1,60 @@
+import os
+import logging
+import time
+import multiprocessing
+from http.server import SimpleHTTPRequestHandler, HTTPServer
+from functools import partial
+
+from blag import blag
+
+
+logger = logging.getLogger(__name__)
+
+
+def get_last_modified(dirs):
+    """Get the last modified time.
+
+    This method recursively goes through `dirs` and returns the most
+    recent modification time time found.
+
+    Parameters
+    ----------
+    dirs : list[str]
+        list of directories to search
+
+    Returns
+    -------
+    int : most recent modification time found in `dirs`
+
+    """
+    last_mtime = 0
+
+    for dir in dirs:
+        for root, dirs, files in os.walk(dir):
+            for f in files:
+                mtime = os.stat(os.path.join(root, f)).st_mtime
+                if mtime > last_mtime:
+                    last_mtime = mtime
+
+    return last_mtime
+
+
+def autoreload(args):
+    dirs = [args.input_dir, args.template_dir, args.static_dir]
+    logger.info(f'Monitoring {dirs} for changes...')
+    last_mtime = get_last_modified(dirs)
+    while True:
+        mtime = get_last_modified(dirs)
+        if mtime > last_mtime:
+            last_mtime = mtime
+            logger.debug('Change detected, rebuilding...')
+            blag.build(args)
+        time.sleep(1)
+
+
+def serve(args):
+    httpd = HTTPServer(('', 8000), partial(SimpleHTTPRequestHandler,
+                       directory=args.output_dir))
+    proc = multiprocessing.Process(target=autoreload, args=(args,))
+    proc.start()
+    httpd.serve_forever()