A refused custom create form came back with its image pool unselected
and its disk and network lists empty: every disk's device and bus and
every MAC had to be chosen again. Adding a disk or a network also reset
the rows already there: each addition rebuilt all rows from an HTML
string, so the earlier disks fell back to the default device and bus
and every NIC got a new random MAC, a typed one included.
The view sends the submitted pool, disks (volume, device, bus) and
networks (name, MAC) back with json_script, built field by field from
the POST (submitted_custom_lists). The rows are cloned from two
<template> elements and filled with textContent and listeners; one
function, sync_custom_lists, derives the images, networks and mac
fields and the device<i>/bus<i> names from the rows in order. Adding or
removing a row leaves the others as they are, and a random MAC that
arrives after one was typed is dropped. On load the page selects the
pool, waits for its volumes, rebuilds each disk with its device, waits
for that device's bus list and selects its bus, rebuilds the networks
with their MACs, and then focuses the first error. A submitted value the
loaded lists no longer have stays selected. The bus and volume loaders
return their requests so that the page can wait on them.
When the server refused a VM create submission (a field error, a busy
resource, a reused submission key, an existing VM name, a missing MAC
for a new disk), the page came back on its first tab with the flavor
dialog closed and every entered value gone: the hand-written fields
showed fixed defaults, and the errors sat in a block at the top of the
page, outside #messages and tied to no field.
The view builds one NewVMForm per create form on the page (custom,
template, one per flavor; create_forms), each with its own defaults; a
hidden form_id, which is also the prefix of the form's field ids, names
the submitted one, and it comes back bound. Every field renders from its
own form and is marked by two small template tags (form_fields:
error_attrs, field_error) when refused; a summary at the top of the
form lists all of its errors, also those of fields it keeps hidden. The
submitted tab or flavor dialog, marked data-form-id, reopens with any
"Advanced" section that holds an error; a reopened dialog shows the
messages too; the template form gets its pool, template and storage
back. base.html's error focus is a function that walks the places an
error can be, and a page can call it once it is set up, as the create
page does. form_id changes nothing in how a POST is processed; one of
an unknown form (a flavor deleted since) has its errors in the
messages. The default video now applies to every create form.
The custom form's disks and networks are not restored yet.
