Add absolute_site_logo_url template tag

This commit adds a {% absolute_site_logo_url %} template tag.
The tag emits an absolute url pointing to either
SITE_LOGO_URL or to the fallback picture.

The tag is used in base email template, in slack message
template, and in "Add MS Teams" page.

This commit also fixes a couple instances where absolute URLs
were constructed like so:

    {% site_root %}/docs/

This would result in incorrect links if Healthchecks is not
running at webserver's root. The correct way is:

    {% site_root %}{% url 'hc-docs' %}

Finally, this commit removes stuff/logo.svg and
stuff/logo-full.svg. Selfhosted sites should not use the
official Healthchecks.io logos, so no point keeping them around
there.

hc/accounts/tests/test_login.py

@@ -34,6 +34,7 @@ class LoginTestCase(BaseTestCase):
         self.assertEqual(message.subject, f"Log in to {settings.SITE_NAME}")
         html = message.alternatives[0][0]
         self.assertIn("http://testserver/static/img/logo.png", html)
+        self.assertIn("http://testserver/docs/", html)
 
     @override_settings(SITE_LOGO_URL="https://example.org/logo.svg")
     def test_it_uses_custom_logo(self):

hc/api/tests/test_notify_slack.py

@@ -26,6 +26,7 @@ class NotifySlackTestCase(BaseTestCase):
         self.channel.save()
         self.channel.checks.add(self.check)
 
+    @override_settings(SITE_ROOT="http://testserver")
     @patch("hc.api.transports.requests.request")
     def test_slack(self, mock_post):
         self._setup_data("123")
@@ -43,6 +44,7 @@ class NotifySlackTestCase(BaseTestCase):
         # The payload should not contain check's code
         serialized = json.dumps(payload)
         self.assertNotIn(str(self.check.code), serialized)
+        self.assertIn("http://testserver/static/img/logo.png", serialized)
 
     @patch("hc.api.transports.requests.request")
     def test_slack_with_complex_value(self, mock_post):

hc/front/templatetags/hc_extras.py

@@ -2,6 +2,7 @@ import re
 
 from django import template
 from django.conf import settings
+from django.templatetags.static import static
 from django.utils.html import escape
 from django.utils.safestring import mark_safe
 from django.utils.timezone import now
@@ -31,6 +32,22 @@ def site_name():
     return settings.SITE_NAME
 
 
+@register.simple_tag
+def absolute_site_logo_url():
+    """ Return absolute URL to site's logo.
+
+    Uses settings.SITE_LOGO_URL if set, uses
+    /static/img/logo.png as fallback.
+
+    """
+
+    url = settings.SITE_LOGO_URL or static("img/logo.png")
+    if url.startswith("/"):
+        url = settings.SITE_ROOT + url
+
+    return url
+
+
 @register.filter
 def mangle_link(s):
     return mark_safe(escape(s).replace(".", "<span>.</span>"))

hc/lib/emails.py

@@ -3,7 +3,6 @@ from threading import Thread
 import time
 
 from django.conf import settings
-from django.templatetags.static import static
 from django.core.mail import EmailMultiAlternatives
 from django.template.loader import render_to_string as render
 
@@ -34,11 +33,6 @@ class EmailThread(Thread):
 
 
 def make_message(name, to, ctx, headers={}):
-    ctx["site_logo_url"] = settings.SITE_LOGO_URL or static("img/logo.png")
-    if ctx["site_logo_url"].startswith("/"):
-        # If it's a relative URL, prepend SITE_ROOT
-        ctx["site_logo_url"] = settings.SITE_ROOT + ctx["site_logo_url"]
-
     subject = render("emails/%s-subject.html" % name, ctx).strip()
     body = render("emails/%s-body-text.html" % name, ctx)
     html = render("emails/%s-body-html.html" % name, ctx)

templates/accounts/login.html

@@ -1,12 +1,12 @@
 {% extends "base.html" %}
-{% load compress static %}
+{% load compress hc_extras static %}
 
 {% block title %}Sign In - {{ site_name }}{% endblock %}
 
 {% block description %}{% endblock %}
 
 {% block head %}
-    <link rel="canonical" href="{{ site_root }}{% url 'hc-login' %}" />
+    <link rel="canonical" href="{% site_root %}{% url 'hc-login' %}" />
 {% endblock %}
 
 {% block content %}

templates/emails/base.html

@@ -105,7 +105,7 @@
             <table border="0" cellpadding="0" cellspacing="0" width="100%" style="max-width: 600px;" class="wrapper">
                 <tr>
                     <td align="center" valign="top" style="padding: 15px 0;" class="logo">
-                        <img alt="{% site_name %}" src="{{ site_logo_url }}" height="50" style="display: block; font-family: Helvetica, Arial, sans-serif; color: #ffffff; font-size: 16px;" border="0">
+                        <img alt="{% site_name %}" src="{% absolute_site_logo_url %}" height="50" style="display: block; font-family: Helvetica, Arial, sans-serif; color: #ffffff; font-size: 16px;" border="0">
                     </td>
                 </tr>
             </table>

templates/emails/login-body-html.html

@@ -34,6 +34,6 @@ The {% site_name %} Team
 <br /><br />
 
 <strong>P.S.</strong> Need help getting started? Check out our
-<a href="{% site_root %}/docs/">help documentation</a>.
+<a href="{% site_root %}{% url 'hc-docs' %}">help documentation</a>.
 Or, just reply to this email with any questions or issues you have.
 {% endblock %}

templates/emails/login-body-text.html

@@ -14,6 +14,6 @@ Thanks,
 The {% site_name %} Team
 
 P.S. Need help getting started? Check out our help documentation
-at {% site_root %}/docs/
+at {% site_root %}{% url 'hc-docs' %}
 Or, just reply to this email with any questions or issues you have.
 {% endblock %}

templates/front/welcome.html

@@ -1,5 +1,5 @@
 {% extends "base.html" %}
-{% load compress humanize i18n static %}
+{% load compress hc_extras i18n static %}
 
 {% block description %}
     <meta name="description" content="{% blocktrans %}Cron Monitoring. Monitor nightly backups, weekly reports, cron jobs and background tasks. Receive alerts when your tasks don't run on time.{% endblocktrans %}">
@@ -7,7 +7,7 @@
 
 
 {% block head %}
-    <link rel="canonical" href="{{ site_root }}" />
+    <link rel="canonical" href="{% site_root %}" />
 {% endblock %}
 
 {% block containers %}

templates/integrations/add_msteams.html

@@ -60,7 +60,7 @@
                 </p>
                 <p>
                     Optionally, upload an icon
-                    (feel free to use <a href="{% static 'img/[email protected]' %}">this one</a>).
+                    (feel free to use <a href="{% absolute_site_logo_url %}">this one</a>).
                 </p>
                 <p>
                     Click on <strong>Create</strong>.

templates/integrations/slack_message.json

@@ -1,7 +1,7 @@
 {% load hc_extras humanize %}
 {
     "username": "{% site_name %}",
-    "icon_url": "{% site_root %}/static/img/[email protected]",
+    "icon_url": "{% absolute_site_logo_url %}",
     "attachments": [{
         {% if check.status == "up" %}
             "color": "good",