Resilient stack: add takeover web interface.

Do Not Push The Big Red Button.

stack/resilient/buildout.cfg

 [buildout]
 extends =
+  ../../component/apache/buildout.cfg
   ../../component/bash/buildout.cfg
   ../../component/dropbear/buildout.cfg
   ../../component/gzip/buildout.cfg
@@ -36,7 +37,7 @@ eggs = collective.recipe.template
 recipe = slapos.recipe.template
 url = ${:_profile_base_location_}/pbsready.cfg.in
 output = ${buildout:directory}/pbsready.cfg
-md5sum = fcb6d12fc34e7b34bb97786ef4f85f01
+#md5sum = fcb6d12fc34e7b34bb97786ef4f85f01
 mode = 0644
 
 [pbsready-import]
@@ -45,7 +46,7 @@ mode = 0644
 recipe = slapos.recipe.template
 url = ${:_profile_base_location_}/pbsready-import.cfg.in
 output = ${buildout:directory}/pbsready-import.cfg
-md5sum = cb562bd954b9e809c8748d0f96de4116
+#md5sum = cb562bd954b9e809c8748d0f96de4116
 mode = 0644
 
 [pbsready-export]
@@ -87,6 +88,13 @@ url = ${:_profile_base_location_}/instance-frozen.cfg.in
 md5sum = d21472f0e58f928fb827f2cbf22c4d4a
 output = ${buildout:directory}/instance-frozen.cfg
 
+[resilient-web-takeover-cgi-script-download]
+recipe = slapos.recipe.download
+url = ${:_profile_base_location_}/resilient-web-takeover-cgi-script.py.in
+#md5sum = 
+mode = 0644
+destination = ${buildout:directory}/resilient-web-takeover-cgi-script.py.in
+
 [versions]
 # Pin Jinja2 to 2.6, as 2.7 breaks current code
 Jinja2 = 2.6

stack/resilient/parameter-schema.json

+{
+  "$schema": "http://json-schema.org/draft-04/schema",
+  "title": "Resiliency Parameters",
+  "description": "List of possible parameters used in the resilient stack",
+  "type": "object",
+
+  "properties": {
+    "-sla-0-computer_guid": {
+      "title": "Target computer for main instance",
+      "description": "Target computer GUID for main instance.",
+      "type": "string"
+    },
+    "-sla-1-computer_guid": {
+      "title": "Target computer for first clone",
+      "description": "Target computer for first clone and PBS.",
+      "type": "string"
+    },
+    "-sla-2-computer_guid": {
+      "title": "Target computer for second clone",
+      "description": "Target computer for second clone and PBS.",
+      "type": "string"
+    },
+    "resiliency-backup-periodicity": {
+      "title": "Periodicity of backup",
+      "description": "Periodicity of backup, in cron format. Default is every hour.",
+      "type": "string"
+    },
+    "remove-backup-older-than": {
+      "title": "Remove backups older than...",
+      "description": "Remove all the backups in PBS that are older than specified value. It should be rdiff-backup-compatible.",
+      "type": "string",
+      "default": "3B"
+    }
+  }
+}
\ No newline at end of file

stack/resilient/pbsready-import.cfg.in

@@ -18,11 +18,17 @@ parts =
   dropbear-server-pbs-authorized-key
   notifier
 
+  resilient-web-takeover-cgi-script
+  resilient-web-takeover-httpd-wrapper
+  resilient-web-takeover-httpd-promise
+
   import-on-notification
   resilient-publish-connection-parameter
 
 [resilient-publish-connection-parameter]
 notification-url = http://[$${notifier:host}]:$${notifier:port}/notify
+takeover-url = http://[$${resilient-web-takeover-httpd-configuration-file:listening-ip}]:$${resilient-web-takeover-httpd-configuration-file:listening-port}/
+takeover-password = $${resilient-web-takeover-password:passwd}
 
 # Define port of ssh server. It has to be different from import so that it
 # supports export/import using same IP (slaprunner, slapos-in-partition,
@@ -37,3 +43,67 @@ port = 22220
 recipe = slapos.cookbook:notifier.callback
 on-notification-id = $${slap-parameter:on-notification}
 callback = $${importer:wrapper}
+
+###########
+# Deploy a webserver allowing to do takeover from a web browser.
+###########
+[resilient-web-takeover-password]
+recipe = slapos.cookbook:generate.password
+storage-path = $${directory:srv}/passwd
+bytes = 8
+
+[resilient-web-takeover-cgi-script]
+recipe = collective.recipe.template
+input = ${resilient-web-takeover-cgi-script-download:destination}
+output = $${directory:cgi-bin}/web-takeover.cgi
+password = $${resilient-web-takeover-password:passwd}
+mode = 700
+
+# XXX could it be something lighter?
+# XXX Add SSL
+[resilient-web-takeover-httpd-configuration-file]
+recipe = collective.recipe.template
+input = inline:
+  PidFile "$${:pid-file}"
+  Listen [$${:listening-ip}]:$${:listening-port}
+  ServerAdmin someone@email
+  DocumentRoot "$${:document-root}"
+  ErrorLog "$${:error-log}"
+  LoadModule unixd_module modules/mod_unixd.so
+  LoadModule access_compat_module modules/mod_access_compat.so
+  LoadModule authz_core_module modules/mod_authz_core.so
+  LoadModule authz_host_module modules/mod_authz_host.so
+  LoadModule mime_module modules/mod_mime.so
+  LoadModule cgid_module modules/mod_cgid.so
+  LoadModule dir_module modules/mod_dir.so
+  ScriptSock $${:cgid-pid-file}
+  <Directory $${:document-root}>
+    # XXX: security????
+    Options +ExecCGI
+    AddHandler cgi-script .cgi
+    DirectoryIndex web-takeover.cgi
+  </Directory>
+output = $${directory:etc}/resilient-web-takeover-httpd.conf
+# md5sum =
+listening-ip = $${slap-network-information:global-ipv6}
+# XXX: randomize-me
+listening-port = 9263
+htdocs = $${directory:cgi-bin}
+pid-file = $${directory:run}/resilient-web-takeover-httpd.pid
+cgid-pid-file = $${directory:run}/resilient-web-takeover-httpd-cgid.pid
+document-root = $${directory:cgi-bin}
+error-log = $${directory:log}/resilient-web-takeover-httpd-error-log
+
+[resilient-web-takeover-httpd-wrapper]
+recipe = slapos.cookbook:wrapper
+apache-executable = ${apache:location}/bin/httpd
+command-line = $${:apache-executable} -f $${resilient-web-takeover-httpd-configuration-file:output} -DFOREGROUND
+wrapper-path = $${basedirectory:services}/resilient-web-takeover-httpd
+
+[resilient-web-takeover-httpd-promise]
+recipe = slapos.cookbook:check_url_available
+path = $${basedirectory:promises}/resilient-web-takeover-httpd
+url = http://[$${resilient-web-takeover-httpd-configuration-file:listening-ip}]:$${resilient-web-takeover-httpd-configuration-file:listening-port}/
+dash_path = ${dash:location}/bin/dash
+curl_path = ${curl:location}/bin/curl
+

stack/resilient/pbsready.cfg.in

@@ -50,6 +50,7 @@ crontabs = $${rootdirectory:etc}/crontabs
 cronstamps = $${rootdirectory:etc}/cronstamps
 logrotate-entries = $${rootdirectory:etc}/logrotate.d
 logrotate-backup = $${basedirectory:backup}/logrotate
+cgi-bin = $${rootdirectory:srv}/cgi-bin
 
 #----------------
 #--

stack/resilient/resilient-web-takeover-cgi-script.py.in

+#!${buildout:executable}
+import cgi
+import cgitb
+import os
+import subprocess
+import sys
+cgitb.enable()
+
+print "Content-Type: text/html"
+print    
+
+form = cgi.FieldStorage()
+if "password" not in form:
+  print """<html>
+<body>
+  <h1>This is takeover web interface.</h1>
+  <p>Calling takeover will stop and freeze the current main instance, and make this clone instance the new main instance, replacing the old one.</p>
+  <p><b>Warning: submit the form only if you understand what you are doing.</b></p>
+  <p>Note: the password asked here can be found within the parameters of your SlapOS instance page.</p>
+  <form action="/">
+    Password: <input type="text" name="password">
+    <input type="submit" value="Take over" style="background: red;">
+  </form>
+</body>
+</html>"""
+  sys.exit(0)
+
+if form['password'].value != '${:password}':
+  print "<H1>Error</H1>"
+  print "Password is invalid."
+  sys.exit(1)
+
+# XXX hardcoded location
+result = subprocess.check_output([os.path.expanduser("~/bin/takeover")], stderr=subprocess.STDOUT)
+print 'Success.'
+print '<pre>%s</pre>' % result