Skip to content

refactor: Refactor HTML map export #934

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
merged 1 commit into from
Oct 15, 2025
Merged

refactor: Refactor HTML map export #934

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
84 changes: 84 additions & 0 deletions lonboard/_html_export.py
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -0,0 +1,84 @@
from __future__ import annotations

from io import StringIO
from typing import IO, TYPE_CHECKING, TextIO, overload

from ipywidgets.embed import dependency_state, embed_minimal_html

if TYPE_CHECKING:
from pathlib import Path

from lonboard import Map


# HTML template to override exported map as 100% height
_HTML_TEMPLATE = """<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>{title}</title>
</head>
<style>
html {{ height: 100%; }}
body {{ height: 100%; overflow: hidden;}}
.widget-subarea {{ height: 100%; }}
.jupyter-widgets-disconnected {{ height: 100%; }}
</style>
<body>
{snippet}
</body>
</html>
"""


@overload
def map_to_html(
m: Map,
*,
filename: None = None,
title: str | None = None,
) -> str: ...


@overload
def map_to_html(
m: Map,
*,
filename: str | Path | TextIO | IO[str],
title: str | None = None,
) -> None: ...


def map_to_html(
m: Map,
*,
filename: str | Path | TextIO | IO[str] | None = None,
title: str | None = None,
) -> str | None:
def inner(fp: str | Path | TextIO | IO[str]) -> None:
original_height = m.height
try:
with m.hold_trait_notifications():
m.height = "100%"
embed_minimal_html(
fp,
views=[m],
title=title or "Lonboard export",
template=_HTML_TEMPLATE,
drop_defaults=False,
# Necessary to pass the state of _this_ specific map. Otherwise, the
# state of all known widgets will be included, ballooning the file size.
state=dependency_state((m), drop_defaults=False),
)
finally:
# If the map had a height before the HTML was generated, reset it.
m.height = original_height

if filename is None:
with StringIO() as sio:
inner(sio)
return sio.getvalue()

else:
inner(filename)
return None
55 changes: 5 additions & 50 deletions lonboard/_map.py
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -1,16 +1,15 @@
from __future__ import annotations

from io import StringIO
from pathlib import Path
from typing import IO, TYPE_CHECKING, Any, TextIO, overload

import ipywidgets
import traitlets
import traitlets as t
from ipywidgets import CallbackDispatcher
from ipywidgets.embed import dependency_state, embed_minimal_html

from lonboard._base import BaseAnyWidget
from lonboard._html_export import map_to_html
from lonboard._layer import BaseLayer
from lonboard._viewport import compute_view
from lonboard.basemap import CartoBasemap
Expand Down Expand Up @@ -39,25 +38,6 @@
# bundler yields lonboard/static/{index.js,styles.css}
bundler_output_dir = Path(__file__).parent / "static"

# HTML template to override exported map as 100% height
_HTML_TEMPLATE = """<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>{title}</title>
</head>
<style>
html {{ height: 100%; }}
body {{ height: 100%; overflow: hidden;}}
.widget-subarea {{ height: 100%; }}
.jupyter-widgets-disconnected {{ height: 100%; }}
</style>
<body>
{snippet}
</body>
</html>
"""


class Map(BaseAnyWidget):
"""The top-level class used to display a map in a Jupyter Widget.
Expand Down Expand Up @@ -115,7 +95,9 @@ def _handle_anywidget_dispatch(
buffers: list[bytes], # noqa: ARG001
) -> None:
if msg.get("kind") == "on-click":
self._click_handlers(tuple(msg.get("coordinate")))
coord = msg.get("coordinate")
if coord is not None:
self._click_handlers(tuple(coord))

super().__init__(layers=layers, **kwargs)
self._click_handlers = CallbackDispatcher()
Expand Down Expand Up @@ -567,34 +549,7 @@ def to_html(
If `filename` is not passed, returns the HTML content as a `str`.

"""

def inner(fp: str | Path | TextIO | IO[str]) -> None:
original_height = self.height
try:
with self.hold_trait_notifications():
self.height = "100%"
embed_minimal_html(
fp,
views=[self],
title=title or "Lonboard export",
template=_HTML_TEMPLATE,
drop_defaults=False,
# Necessary to pass the state of _this_ specific map. Otherwise, the
# state of all known widgets will be included, ballooning the file size.
state=dependency_state((self), drop_defaults=False),
)
finally:
# If the map had a height before the HTML was generated, reset it.
self.height = original_height

if filename is None:
with StringIO() as sio:
inner(sio)
return sio.getvalue()

else:
inner(filename)
return None
return map_to_html(self, filename=filename, title=title)

def as_html(self) -> HTML:
"""Render the current map as a static HTML file in IPython.
Expand Down