Font allow using google fonts directly (#3243)

esphome/components/font/__init__.py

@@ -1,12 +1,29 @@
 import functools
+from pathlib import Path
+import hashlib
+import re
+
+import requests
 
 from esphome import core
 from esphome.components import display
 import esphome.config_validation as cv
 import esphome.codegen as cg
-from esphome.const import CONF_FILE, CONF_GLYPHS, CONF_ID, CONF_RAW_DATA_ID, CONF_SIZE
+from esphome.const import (
+    CONF_FAMILY,
+    CONF_FILE,
+    CONF_GLYPHS,
+    CONF_ID,
+    CONF_RAW_DATA_ID,
+    CONF_TYPE,
+    CONF_SIZE,
+    CONF_PATH,
+    CONF_WEIGHT,
+)
 from esphome.core import CORE, HexInt
 
+
+DOMAIN = "font"
 DEPENDENCIES = ["display"]
 MULTI_CONF = True
 
@@ -71,6 +88,128 @@ def validate_truetype_file(value):
     return cv.file_(value)
 
 
+def _compute_gfonts_local_path(value) -> Path:
+    name = f"{value[CONF_FAMILY]}@{value[CONF_WEIGHT]}@{value[CONF_ITALIC]}@v1"
+    base_dir = Path(CORE.config_dir) / ".esphome" / DOMAIN
+    h = hashlib.new("sha256")
+    h.update(name.encode())
+    return base_dir / h.hexdigest()[:8] / "font.ttf"
+
+
+TYPE_LOCAL = "local"
+TYPE_GFONTS = "gfonts"
+LOCAL_SCHEMA = cv.Schema(
+    {
+        cv.Required(CONF_PATH): validate_truetype_file,
+    }
+)
+CONF_ITALIC = "italic"
+FONT_WEIGHTS = {
+    "thin": 100,
+    "extra-light": 200,
+    "light": 300,
+    "regular": 400,
+    "medium": 500,
+    "semi-bold": 600,
+    "bold": 700,
+    "extra-bold": 800,
+    "black": 900,
+}
+
+
+def validate_weight_name(value):
+    return FONT_WEIGHTS[cv.one_of(*FONT_WEIGHTS, lower=True, space="-")(value)]
+
+
+def download_gfonts(value):
+    wght = value[CONF_WEIGHT]
+    if value[CONF_ITALIC]:
+        wght = f"1,{wght}"
+    name = f"{value[CONF_FAMILY]}@{value[CONF_WEIGHT]}"
+    url = f"https://fonts.googleapis.com/css2?family={value[CONF_FAMILY]}:wght@{wght}"
+
+    path = _compute_gfonts_local_path(value)
+    if path.is_file():
+        return value
+    try:
+        req = requests.get(url)
+        req.raise_for_status()
+    except requests.exceptions.RequestException as e:
+        raise cv.Invalid(
+            f"Could not download font for {name}, please check the fonts exists "
+            f"at google fonts ({e})"
+        )
+    match = re.search(r"src:\s+url\((.+)\)\s+format\('truetype'\);", req.text)
+    if match is None:
+        raise cv.Invalid(
+            f"Could not extract ttf file from gfonts response for {name}, "
+            f"please report this."
+        )
+
+    ttf_url = match.group(1)
+    try:
+        req = requests.get(ttf_url)
+        req.raise_for_status()
+    except requests.exceptions.RequestException as e:
+        raise cv.Invalid(f"Could not download ttf file for {name} ({ttf_url}): {e}")
+
+    path.parent.mkdir(exist_ok=True, parents=True)
+    path.write_bytes(req.content)
+    return value
+
+
+GFONTS_SCHEMA = cv.All(
+    {
+        cv.Required(CONF_FAMILY): cv.string_strict,
+        cv.Optional(CONF_WEIGHT, default="regular"): cv.Any(
+            cv.int_, validate_weight_name
+        ),
+        cv.Optional(CONF_ITALIC, default=False): cv.boolean,
+    },
+    download_gfonts,
+)
+
+
+def validate_file_shorthand(value):
+    value = cv.string_strict(value)
+    if value.startswith("gfonts://"):
+        match = re.match(r"^gfonts://([^@]+)(@.+)?$", value)
+        if match is None:
+            raise cv.Invalid("Could not parse gfonts shorthand syntax, please check it")
+        family = match.group(1)
+        weight = match.group(2)
+        data = {
+            CONF_TYPE: TYPE_GFONTS,
+            CONF_FAMILY: family,
+        }
+        if weight is not None:
+            data[CONF_WEIGHT] = weight[1:]
+        return FILE_SCHEMA(data)
+    return FILE_SCHEMA(
+        {
+            CONF_TYPE: TYPE_LOCAL,
+            CONF_PATH: value,
+        }
+    )
+
+
+TYPED_FILE_SCHEMA = cv.typed_schema(
+    {
+        TYPE_LOCAL: LOCAL_SCHEMA,
+        TYPE_GFONTS: GFONTS_SCHEMA,
+    }
+)
+
+
+def _file_schema(value):
+    if isinstance(value, str):
+        return validate_file_shorthand(value)
+    return TYPED_FILE_SCHEMA(value)
+
+
+FILE_SCHEMA = cv.Schema(_file_schema)
+
+
 DEFAULT_GLYPHS = (
     ' !"%()+=,-.:/0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ_abcdefghijklmnopqrstuvwxyz°'
 )
@@ -79,7 +218,7 @@ CONF_RAW_GLYPH_ID = "raw_glyph_id"
 FONT_SCHEMA = cv.Schema(
     {
         cv.Required(CONF_ID): cv.declare_id(Font),
-        cv.Required(CONF_FILE): validate_truetype_file,
+        cv.Required(CONF_FILE): FILE_SCHEMA,
         cv.Optional(CONF_GLYPHS, default=DEFAULT_GLYPHS): validate_glyphs,
         cv.Optional(CONF_SIZE, default=20): cv.int_range(min=1),
         cv.GenerateID(CONF_RAW_DATA_ID): cv.declare_id(cg.uint8),
@@ -93,9 +232,13 @@ CONFIG_SCHEMA = cv.All(validate_pillow_installed, FONT_SCHEMA)
 async def to_code(config):
     from PIL import ImageFont
 
-    path = CORE.relative_config_path(config[CONF_FILE])
+    conf = config[CONF_FILE]
+    if conf[CONF_TYPE] == TYPE_LOCAL:
+        path = CORE.relative_config_path(conf[CONF_PATH])
+    elif conf[CONF_TYPE] == TYPE_GFONTS:
+        path = _compute_gfonts_local_path(conf)
     try:
-        font = ImageFont.truetype(path, config[CONF_SIZE])
+        font = ImageFont.truetype(str(path), config[CONF_SIZE])
     except Exception as e:
         raise core.EsphomeError(f"Could not load truetype file {path}: {e}")