Added input form constraints

setup/templates/steps/compose/expose.html

@@ -0,0 +1,39 @@
+{% call macros.panel("info", "Step 2 - expose Mailu to the world") %}
+<p>A mail server must be exposed to the world to receive emails, send emails,
+and let users access their mailboxes. Mailu has some flexibility in the way
+you expose it to the world.</p>
+
+<p>Among Mailu services, the <em>front</em> server is the one accepting connections,
+be it directly from the outside world, through a reverse proxy or in any
+complex configuration that you might want to setup. It needs to listen on some
+IP addresses in order to expose its public services. You must at least setup
+an IPv4 or an IPv6 address if you wish to access Mailu.</p>
+
+<p><span class="label label-warning">Warning</span> You must use specific addresses, please
+avoid generic all-interfaces addresses like <code>0.0.0.0</code> or <code>::</code>.</p>
+
+<div class="form-group">
+  <label>IPv4 listen address</label>
+<!--   Validates IPv4 address -->
+  <input class="form-control" type="text" name="bind4" value="127.0.0.1" required
+  		pattern="^((25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.){3}(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)$">
+</div>
+
+<div class="form-group">
+  <label>IPv6 listen address</label>
+<!--   Validates IPv6 address -->
+  <input class="form-control" type="text" name="bind6" value="::1"
+  		pattern="/^(((?=.*(::))(?!.*\3.+\3))\3?|([\dA-F]{1,4}(\3|:\b|$)|\2))(?4){5}((?4){2}|(((2[0-4]|1\d|[1-9])?\d|25[0-5])\.?\b){4})\z/i">
+</div>
+
+<p>You server will be available under a main hostname but may expose multiple public
+hostnames. Every e-mail domain that points to this server must have one of the
+hostnames in its <code>MX</code> record. Hostnames must be coma-separated.</p>
+
+<div class="form-group">
+  <label>Public hostnames</label>
+<!--   Validates hostname or list of hostnames -->
+  <input class="form-control" type="text" name="hostnames" placeholder="my.host.name,other.host.name" multiple required
+    	pattern="^(?:(?:\w+(?:-+\w+)*\.)+[a-z]+)*(?:,(?:(?:\w+(?:-+\w+)*\.)+[a-z]+)\s*)*$">
+</div>
+{% endcall %}