dashboard: fix subprocesses blocking the event loop (#5772)

* dashboard: fix subprocesses blocking the event loop

- break apart the util module
- adds a new util to run subprocesses with asyncio

* take a list

esphome/dashboard/util/itertools.py

@@ -0,0 +1,22 @@
+from __future__ import annotations
+
+from collections.abc import Iterable
+from functools import partial
+from itertools import islice
+from typing import Any
+
+
+def take(take_num: int, iterable: Iterable) -> list[Any]:
+    """Return first n items of the iterable as a list.
+
+    From itertools recipes
+    """
+    return list(islice(iterable, take_num))
+
+
+def chunked(iterable: Iterable, chunked_num: int) -> Iterable[Any]:
+    """Break *iterable* into lists of length *n*.
+
+    From more-itertools
+    """
+    return iter(partial(take, chunked_num, iter(iterable)), [])

esphome/dashboard/util/password.py

@@ -0,0 +1,11 @@
+from __future__ import annotations
+
+import hashlib
+
+
+def password_hash(password: str) -> bytes:
+    """Create a hash of a password to transform it to a fixed-length digest.
+
+    Note this is not meant for secure storage, but for securely comparing passwords.
+    """
+    return hashlib.sha256(password.encode()).digest()

esphome/dashboard/util/subprocess.py

@@ -0,0 +1,31 @@
+from __future__ import annotations
+
+import asyncio
+from collections.abc import Iterable
+
+
+async def async_system_command_status(command: Iterable[str]) -> bool:
+    """Run a system command checking only the status."""
+    process = await asyncio.create_subprocess_exec(
+        *command,
+        stdin=asyncio.subprocess.DEVNULL,
+        stdout=asyncio.subprocess.DEVNULL,
+        stderr=asyncio.subprocess.DEVNULL,
+        close_fds=False,
+    )
+    await process.wait()
+    return process.returncode == 0
+
+
+async def async_run_system_command(command: Iterable[str]) -> tuple[bool, bytes, bytes]:
+    """Run a system command and return a tuple of returncode, stdout, stderr."""
+    process = await asyncio.create_subprocess_exec(
+        *command,
+        stdin=asyncio.subprocess.DEVNULL,
+        stdout=asyncio.subprocess.PIPE,
+        stderr=asyncio.subprocess.PIPE,
+        close_fds=False,
+    )
+    stdout, stderr = await process.communicate()
+    await process.wait()
+    return process.returncode, stdout, stderr

esphome/dashboard/util/text.py

@@ -0,0 +1,25 @@
+from __future__ import annotations
+
+import unicodedata
+
+from esphome.const import ALLOWED_NAME_CHARS
+
+
+def strip_accents(value):
+    return "".join(
+        c
+        for c in unicodedata.normalize("NFD", str(value))
+        if unicodedata.category(c) != "Mn"
+    )
+
+
+def friendly_name_slugify(value):
+    value = (
+        strip_accents(value)
+        .lower()
+        .replace(" ", "-")
+        .replace("_", "-")
+        .replace("--", "-")
+        .strip("-")
+    )
+    return "".join(c for c in value if c in ALLOWED_NAME_CHARS)