admin: Add log out button

[BBaoVanC]

Fixes #552

Adds a logout button to the header, in the top right.

Tasks:

• CHANGES.rst

[ix5]

See inline comments

Edit 2: Whoops, I think that'd delete all current site cookies. Need a better way.

Edit: My idea, not complete:

diff --git a/isso/css/admin.css b/isso/css/admin.css
index 3f694c3..fd2bbb5 100644
--- a/isso/css/admin.css
+++ b/isso/css/admin.css
@@ -30,16 +30,25 @@ input {
 }
 .header header {
     display: block;
-    float: left;
     font-weight: normal;
     margin-right: 16.0363%;
-    width: 41.9818%;
 }
 .header header .logo {
-    float: left;
     max-height: 60px;
     padding-right: 12px;
 }
+.header header .title {
+    display: inline;
+}
+.header header .title a {
+    display: inline-block;
+    width: 41.9818%;
+}
+.header header .logout {
+    float: right;
+    margin-top: 0.8em;
+    line-height: 1.6em;
+}
 .header header h1 {
     font-size: 1.55em;
     margin-bottom: 0.3em;
diff --git a/isso/js/admin.js b/isso/js/admin.js
index 5b1e508..8d48167 100644
--- a/isso/js/admin.js
+++ b/isso/js/admin.js
@@ -124,4 +124,11 @@ function send_edit(com_id, hash, isso_host_script) {
     edit(com_id, hash, author, email, website, comment, isso_host_script);
     stop_edit(com_id, true);
 }
-
+function log_out() {
+    // Delete cookie
+    var cookie_name = "admin-session";
+    var domain = window.location.hostname;
+    document.cookie = cookie_name + "=; Max-Age=0; domain=" + domain + "; path=/";
+    // Redirect back to /admin login page
+    window.location.href = "admin";
+}
diff --git a/isso/templates/admin.html b/isso/templates/admin.html
index 3332c5b..10dd6f9 100644
--- a/isso/templates/admin.html
+++ b/isso/templates/admin.html
@@ -16,6 +16,7 @@
             <h2>Administration</h2>
           </a>
         </div>
+        <a id="logout" class="logout label" onClick="javascript:log_out()">Log out</a>
       </header>
     </div>
     <div class="outer">

[BBaoVanC]

Wow, the admin CSS is a horrible mess right now. is it better to just do as little change here (like I already have) so it works, and then make another pull request to clean up the CSS?

[ix5]

Wow, the admin CSS is a horrible mess right now. is it better to just do as little change here (like I already have) so it works, and then make another pull request to clean up the CSS?

Re: Admin CSS: Yes, please open another PR for that and keep this PR focused.

Re: Clearing the cookies: I'm not quite sure whether we need to match SameSite and Secure attributes from server when clearing cookies. Also, IMO we can use a bit more "modern" JS and modern Interfaces such as CookieStore in the admin (just keep the client JS as backward-compatible as possible).

[ix5]

@BBaoVanC would you mind applying the PR feedback? I know it's a bit much to ask, but we should at least try to keep track of SameSite and Secure stuff, I think.

[jelmer]

Please rebase this PR after the force-push.

[jelmer]

Please rebase

[BBaoVanC]

Please rebase

Done

[BBaoVanC]

Is there anything else this PR needs? I believe when I last looked at it I had already applied @ix5's changes.