zulip/scripts/setup/inline_email_css.py

111 lines
4.1 KiB
Python
Executable File

#!/usr/bin/env python3
import os
from typing import Set
from cssutils import profile
from cssutils.profiles import Profiles, macros, properties
from premailer import Premailer
ZULIP_PATH = os.path.join(os.path.dirname(os.path.abspath(__file__)), "../../")
EMAIL_TEMPLATES_PATH = os.path.join(ZULIP_PATH, "templates", "zerver", "emails")
COMPILED_EMAIL_TEMPLATES_PATH = os.path.join(EMAIL_TEMPLATES_PATH, "compiled")
CSS_SOURCE_PATH = os.path.join(EMAIL_TEMPLATES_PATH, "email.css")
def configure_cssutils() -> None:
# These properties are not supported by cssutils by default and will
# result in warnings when premailer package is run.
properties[Profiles.CSS_LEVEL_2]["-ms-interpolation-mode"] = r"none|bicubic|nearest-neighbor"
properties[Profiles.CSS_LEVEL_2]["-ms-text-size-adjust"] = r"none|auto|{percentage}"
properties[Profiles.CSS_LEVEL_2]["mso-table-lspace"] = r"0|{num}(pt)"
properties[Profiles.CSS_LEVEL_2]["mso-table-rspace"] = r"0|{num}(pt)"
properties[Profiles.CSS_LEVEL_2]["-webkit-text-size-adjust"] = r"none|auto|{percentage}"
properties[Profiles.CSS_LEVEL_2]["mso-hide"] = "all"
properties[Profiles.CSS_LEVEL_2]["pointer-events"] = (
r"auto|none|visiblePainted|"
r"visibleFill|visibleStroke|"
r"visible|painted|fill|stroke|all|inherit"
)
profile.addProfiles(
[(Profiles.CSS_LEVEL_2, properties[Profiles.CSS_LEVEL_2], macros[Profiles.CSS_LEVEL_2])]
)
configure_cssutils()
def inline_template(template_source_name: str) -> None:
template_name = template_source_name.split(".source.html")[0]
template_path = os.path.join(EMAIL_TEMPLATES_PATH, template_source_name)
compiled_template_path = os.path.join(
os.path.dirname(template_path), "compiled", os.path.basename(template_name) + ".html"
)
os.makedirs(os.path.dirname(compiled_template_path), exist_ok=True)
with open(template_path) as template_source_file:
template_str = template_source_file.read()
output = Premailer(
template_str, external_styles=[CSS_SOURCE_PATH], allow_loading_external_files=True
).transform()
output = escape_jinja2_characters(output)
# Premailer.transform will try to complete the DOM tree,
# adding html, head, and body tags if they aren't there.
# While this is correct for the email_base_default template,
# it is wrong for the other templates that extend this
# template, since we'll end up with 2 copipes of those tags.
# Thus, we strip this stuff out if the template extends
# another template.
if template_name not in ["email_base_default", "email_base_marketing", "macros"]:
output = strip_unnecesary_tags(output)
if (
"zerver/emails/compiled/email_base_default.html" in output
or "zerver/emails/compiled/email_base_marketing.html" in output
or "zerver/emails/email_base_messages.html" in output
):
assert output.count("<html>") == 0
assert output.count("<body>") == 0
assert output.count("</html>") == 0
assert output.count("</body>") == 0
with open(compiled_template_path, "w") as final_template_file:
final_template_file.write(output)
def escape_jinja2_characters(text: str) -> str:
escaped_jinja2_characters = [("%7B%7B%20", "{{ "), ("%20%7D%7D", " }}"), ("&gt;", ">")]
for escaped, original in escaped_jinja2_characters:
text = text.replace(escaped, original)
return text
def strip_unnecesary_tags(text: str) -> str:
end_block = "</body>\n</html>"
start_block = "{% extends"
start = text.find(start_block)
end = text.rfind(end_block)
if start != -1 and end != -1:
text = text[start:end]
return text
else:
raise ValueError(f"Template does not have {start_block} or {end_block}")
def get_all_templates_from_directory(directory: str) -> Set[str]:
result = set()
for f in os.listdir(directory):
if f.endswith(".source.html"):
result.add(f)
return result
if __name__ == "__main__":
templates_to_inline = get_all_templates_from_directory(EMAIL_TEMPLATES_PATH)
for template_source_name in templates_to_inline:
inline_template(template_source_name)