luci-app-lxc: Download list of available distributions

There was harcoded list of available images. Instead of it, LuCI LXC app will
now try to download list of available container images.

Signed-off-by: Michal Hrusecky <michal.hrusecky@nic.cz>

utils/luci-app-lxc/files/controller/lxc.lua

@@ -59,6 +59,9 @@ function index()
 	page = entry({"admin", "services", "lxc_action"}, call("lxc_action"), nil)
 	page.leaf = true
 
+	page = entry({"admin", "services", "lxc_get_downloadable"}, call("lxc_get_downloadable"), nil)
+	page.leaf = true
+
 	page = entry({"admin", "services", "lxc_configuration_get"}, call("lxc_configuration_get"), nil)
 	page.leaf = true
 
@@ -67,6 +70,27 @@ function index()
 
 end
 
+function lxc_get_downloadable()
+	luci.http.prepare_content("application/json")
+
+	local f = io.popen('uname -m', 'r')
+	local target = f:read('*a')
+	f:close()
+	target = target:gsub("^%s*(.-)%s*$", "%1")
+
+	local templates = {}
+
+	local f = io.popen('lxc-create -n just_want_to_list_available_lxc_templates -t download -- --list', 'r')
+
+	for line in f:lines() do
+		local dist,version = line:match("^(%S+)%s+(%S+)%s+" .. target .. "%s+default%s+%S+$")
+		if dist~=nil and version~=nil then templates[#templates + 1] = dist .. ":" .. version end
+	end
+
+	f:close()
+	luci.http.write_json(templates)
+end
+
 function lxc_create(lxc_name, lxc_template)
 	luci.http.prepare_content("text/plain")
 

utils/luci-app-lxc/files/view/lxc.htm

@@ -47,7 +47,6 @@ Author: Petar Koretic <petar.koretic@sartura.hr>
 				</td>
 				<td>
 					<select id="s_template" class="cbi-input-select cbi-button">
-						<option value="openwrt:bb">OpenWrt BB</option>
 					</select>
 				</td>
 				<td>
@@ -438,4 +437,22 @@ Author: Petar Koretic <petar.koretic@sartura.hr>
 	}
 
 	lxc_list_update()
+
+	new XHR().get('<%=luci.dispatcher.build_url("admin", "services")%>/lxc_get_downloadable', null,
+	function(x, data)
+	{
+		if (!x) return;
+
+		var lxc_count = Object.keys(data).length
+		if (!data || !lxc_count) return;
+		var select = document.getElementById("s_template");
+		for(var key in data)
+		{
+			var option = document.createElement('option');
+			option.value = data[key];
+			option.text = data[key].replace(/[_:]/, ' ');
+			select.add(option, -1);
+		}
+	})
+
 //]]></script>