[pve-devel] [PATCH v1 pve-storage 5/8] pluginbase: document hooks

[Maximiliano Sandoval]

Max Carrara <m.carrara at proxmox.com> writes:

> Add docstrings for the following methods:
> - on_add_hook
> - on_update_hook
> - on_delete_hook
>
> Signed-off-by: Max Carrara <m.carrara at proxmox.com>
> ---
>  src/PVE/Storage/PluginBase.pm | 85 ++++++++++++++++++++++++++++++-----
>  1 file changed, 74 insertions(+), 11 deletions(-)
>
> diff --git a/src/PVE/Storage/PluginBase.pm b/src/PVE/Storage/PluginBase.pm
> index 8a61dc3..b3ce684 100644
> --- a/src/PVE/Storage/PluginBase.pm
> +++ b/src/PVE/Storage/PluginBase.pm
> @@ -626,29 +626,92 @@ sub find_free_diskname {
>
>  =head2 HOOKS
>
> +The following methods are called whenever a storage associated with the given
> +plugin is added, updated, or deleted. These methods are useful for:
> +
> +=over
> +
> +=item * Setting up certain prerequisites when adding the storage (and then
> +tearing them down again when the storage is deleted)
> +
> +=item * Handling sensitive parameters that shouldn't be written directly
> +to C</etc/pve/storage.cfg> and ought to be stored elsewhere
> +
> +=item * Ensuring that certain conditions in the configuration are being upheld
> +that cannot be done via the remaining API otherwise
> +
> +=back
> +
> +and more.
> +
> +=cut
> +
> +=head3 $plugin->on_add_hook($storeid, \%scfg, %param)
> +
> +=head3 $plugin->on_add_hook(...)
> +
> +B<OPTIONAL:> May be implemented in a storage plugin.
> +
> +Called during the addition of a storage, before the new storage configuration
> +gets written.
> +
> +C<%param> contains additional key-value arguments, usually sensitive keys that
> +have been extracted from C<\%scfg> in order not to write them to the storage
> +configuration.
> +
> +C<die>s in order to abort the addition if there are (grave) problems.
> +
> +C</etc/pve/storage.cfg> is B<locked> when this method is called.

nit: Perhaps it would be more precise to say something like

```
C</etc/pve/storage.cfg> is B<locked> while this method is called.
```

to make it clear the lock will, at the very least, outlive whatever
happens inside on_add_hook. Similar for the rest.

> +
>  =cut
>
> -# called during addition of storage (before the new storage config got written)
> -# die to abort addition if there are (grave) problems
> -# NOTE: runs in a storage config *locked* context
>  sub on_add_hook {
>      my ($class, $storeid, $scfg, %param) = @_;
>      return undef;
>  }
>
> -# called during storage configuration update (before the updated storage config got written)
> -# die to abort the update if there are (grave) problems
> -# NOTE: runs in a storage config *locked* context
> +=head3 $plugin->on_update_hook($storeid, \%scfg, %param)
> +
> +=head3 $plugin->on_update_hook(...)
> +
> +B<OPTIONAL:> May be implemented in a storage plugin.
> +
> +Called during the update of a storage configuration, before the new
> +configuration gets written.
> +
> +C<%param> contains additional key-value arguments, usually sensitive keys that
> +have been extracted from C<\%scfg> in order not to write them to the storage
> +configuration.
> +
> +C<die>s in order to abort the config update if there are (grave) problems.
> +
> +C</etc/pve/storage.cfg> is B<locked> when this method is called.
> +
> +=cut
> +
>  sub on_update_hook {
>      my ($class, $storeid, $scfg, %param) = @_;
>      return undef;
>  }
>
> -# called during deletion of storage (before the new storage config got written)
> -# and if the activate check on addition fails, to cleanup all storage traces
> -# which on_add_hook may have created.
> -# die to abort deletion if there are (very grave) problems
> -# NOTE: runs in a storage config *locked* context
> +=head3 $plugin->on_delete_hook($storeid, \%scfg)
> +
> +=head3 $plugin->on_delete_hook(...)
> +
> +B<OPTIONAL:> May be implemented in a storage plugin.
> +
> +Called during the deletion of a storage, before the new storage configuration
> +gets written. Also gets called if the activation check during storage
> +addition fails in order to clean up all traces which
> +C<L<< on_add_hook()|/"$plugin->on_add_hook($storeid, \%scfg, %param)" >>>
> +may have created.
> +
> +C<die>s in order to abort the deletion of there are (very grave) problems.
> +
> +C</etc/pve/storage.cfg> is B<locked> when this method is called.
> +
> +=cut
> +
>  sub on_delete_hook {
>      my ($class, $storeid, $scfg) = @_;
>      return undef;