add counter.svg

Signed-off-by: Ari Archer <ari@ari.lt>

src/aw/util.py

@@ -2,6 +2,8 @@
 # -*- coding: utf-8 -*-
 """utilities"""
 
+from html import escape as html_escape
+
 import bleach
 from markdown import markdown
 from markupsafe import Markup
@@ -23,3 +25,43 @@ def markdown_to_html(text: str) -> Markup:
             protocols={"http", "https"},
         )
     )
+
+
+def text2svg(
+    text: str,
+    fill: str = "#fff",
+    font: str = "sans-serif",
+    size: float = 16,
+    baseline: float = 1,
+    padding: float = 1,
+    ratio: float = 1,  # usually 2 for monospace
+) -> str:
+    """convert count to svg
+
+    fill -- text colour
+    font -- font family
+    size -- font size in pixels
+    baseline -- baseline offset
+    padding -- padding of characters
+    ratio -- character ratio
+
+    embedding :
+
+    <img
+        id="my-stuff"
+        src="..."
+        style="display:inline;height:1em;vertical-align:top"
+        alt="my stuff :3"
+    />
+    """
+
+    fill = html_escape(fill)
+    font = html_escape(font)
+
+    svg: str = (
+        f'<svg xmlns="http://www.w3.org/2000/svg" width="{len(text) + padding * ratio}ch" height="{size}" font-size="{size}">'
+    )
+    svg += f'<text x="50%" y="{size - baseline}" text-anchor="middle" fill="{fill}" font-family="{font}">{html_escape(text)}</text>'
+    svg += "</svg>"
+
+    return svg

src/aw/views.py

@@ -10,7 +10,7 @@ import flask
 import validators
 from werkzeug.wrappers import Response
 
-from . import email, models
+from . import email, models, util
 from .c import c
 from .routing import Bp
 
@@ -229,6 +229,23 @@ def favicon() -> Response:
     )
 
 
+@views.get("/counter.svg")
+def counter() -> flask.Response:
+    """counter"""
+    return flask.Response(
+        util.text2svg(
+            text=str(models.Counter.first().inc().count),
+            fill=flask.request.args.get("fill", "#fff"),
+            font=flask.request.args.get("font", "sans-serif"),
+            size=float(flask.request.args.get("size", 16)),
+            baseline=float(flask.request.args.get("baseline", 1)),
+            padding=float(flask.request.args.get("padding", 1)),
+            ratio=float(flask.request.args.get("radio", 1)),
+        ),
+        mimetype="image/svg+xml",
+    )
+
+
 @views.get("/captcha.png")
 def captcha() -> flask.Response:
     """CAPTCHA"""