From 58aec49efd733ca80ad057d742970011b76b9747 Mon Sep 17 00:00:00 2001
From: Oliver Lambson <oliverlambson@gmail.com>
Date: Mon, 26 Aug 2024 04:49:24 +0200
Subject: [PATCH] base64url encode figure ids

---
 bored-charts/boredcharts/__init__.py |  2 +-
 bored-charts/boredcharts/jinja.py    |  5 ++++-
 bored-charts/boredcharts/utils.py    | 28 ++++++++++++++++++++++++++++
 3 files changed, 33 insertions(+), 2 deletions(-)

diff --git a/bored-charts/boredcharts/__init__.py b/bored-charts/boredcharts/__init__.py
index b3aa7f5..85da412 100644
--- a/bored-charts/boredcharts/__init__.py
+++ b/bored-charts/boredcharts/__init__.py
@@ -1,4 +1,4 @@
-__version__ = "0.13.0"
+__version__ = "0.13.1"
 
 from boredcharts.router import FigureRouter
 from boredcharts.webapp import boredcharts
diff --git a/bored-charts/boredcharts/jinja.py b/bored-charts/boredcharts/jinja.py
index 262eaf3..0544e0e 100644
--- a/bored-charts/boredcharts/jinja.py
+++ b/bored-charts/boredcharts/jinja.py
@@ -15,6 +15,8 @@
 from markupsafe import Markup
 from plotly.graph_objects import Figure
 
+from boredcharts.utils import uuid_to_urlid
+
 logger = logging.getLogger("boredcharts")
 
 
@@ -68,7 +70,8 @@ def plotly_to_html(fig: Figure) -> Markup:
 
 def altair_to_html(chart: alt.typing.ChartType) -> Markup:
     """Renders an Altair Chart as HTML."""
-    figid = f"vis-{uuid.uuid4()}"  # html id can't start with digit
+    id_ = uuid_to_urlid(uuid.uuid4())
+    figid = f"vis-{id_}"  # html id can't start with digit
     return Markup(
         chart.to_html(
             fullhtml=False,
diff --git a/bored-charts/boredcharts/utils.py b/bored-charts/boredcharts/utils.py
index 12663bc..3f0388a 100644
--- a/bored-charts/boredcharts/utils.py
+++ b/bored-charts/boredcharts/utils.py
@@ -1,5 +1,7 @@
 from __future__ import annotations
 
+import base64
+import uuid
 from pathlib import Path
 from typing import NamedTuple
 
@@ -38,3 +40,29 @@ def to_url_path(path: Path) -> str:
     if path.name:
         path = path.with_suffix("")
     return str(Path("/") / path)
+
+
+def uuid_to_urlid(uuid_: uuid.UUID) -> str:
+    """Convert a UUID to a short URL-safe string.
+
+    >>> import base64
+    >>> import uuid
+    >>> id_ = uuid.UUID('5d98d578-2731-4a4d-b666-70ca16f10aa2')
+    >>> url_id = uuid_to_urlid(id_)
+    >>> print(url_id)
+    XZjVeCcxSk22ZnDKFvEKog
+    """
+    return base64.urlsafe_b64encode(uuid_.bytes).rstrip(b"=").decode("utf-8")
+
+
+def urlid_to_uuid(url: str) -> uuid.UUID:
+    """Convert a base64url encoded UUID string to a UUID.
+
+    >>> import base64
+    >>> import uuid
+    >>> url_id = 'XZjVeCcxSk22ZnDKFvEKog'
+    >>> id_ = urlid_to_uuid(url_id)
+    >>> print(id_)
+    5d98d578-2731-4a4d-b666-70ca16f10aa2
+    """
+    return uuid.UUID(bytes=base64.urlsafe_b64decode(url + "=" * (len(url) % 4)))