Re: [mh] Your help re Genericising Error and log handling

Giles,

First, thank you for all the attention you and others are recently 
giving to MH.

I'm not sure I completely understand your proposal, but I'm certainly in 
favor of the concept. If I have any thoughts to offer, it's in regards 
to the implementation...

First, I would want existing code that uses print_log to continue to 
work but use your new structure. So I would change the internal function 
of print_log to allow (but not require) calling out to user code. 
Otherwise you wind up having two logging calls with different results 
and split logging. "This way madness lies." Perhaps that is what you 
were suggesting in your final question regarding print_log.

Next, I'm a fan of the "designated-directory" approach, such as was used 
in the old /etc/init/rc5.d boot initialization system (along with many 
others). What would you think of creating a reserved directory name in 
local/code (may be "local/code/print_log")? If that directory exists and 
if there are files in in, print_log calls them in alphabetical order, 
providing the calling parameters you've already described. That way, 
specific severities, categories, or whatever could have their own log 
handlers code instead of needing to having everything in one file. I 
might one one per device ("oh, xyz just went offline - better restart 
something"), whereas you might have a file for each severity level 
("warning = send an e-mail; critical = send a text too"). And, of 
course, if the user does nothing with this directory, print_log just 
does it's ordinary job like it does now. So, no transition at all, just 
a new capability for those that want to take advantage of it.

I hope you find something useful in these musings. Please keep up the 
good work.

-Brian M

On 1/12/21 8:23 AM, Giles Godart-Brown wrote:
>
> Jeff and I have been wondering about creating a more generic error 
> handling system that would allow implementers to easily modify what 
> happens when an error or log entry occurs, for example send emails or 
> SMS. Here is a summary of what we are thinking;
>
> 1) We start with the MisterHouse syslog severity levels viz;
>
>   * EMERGENCY
>   * ALERT
>   * CRITICAL
>   * ERROR
>   * WARNING
>   * NOTICE
>   * INFORMATIONAL
>   * DEBUG
>
> 2) We create a new handle_log routine that is passed a severity as 
> above, a category e.g. "in my routine" and a message, something like
>
> <snip>
>
> sub handle_log {
>     my ($message, $severity, $category ) = @_;
>     if ($severity eq "EMERGENCY") {
>         # put your code to handle Emergencies here e.g. send email
>     } elsif {
>     if ($severity eq "ALERT") {
>         # put your code to handle Alerts here e.g. send a send Growl 
> and SMS
>     } elsif {
>     if ($severity eq "CRITICAL") {
>
>         # put your code to handle Critical errors here e.g. send email
>     } elsif {
>
>     if ($severity eq "ERROR") {
>         # put your code to handle Error here e.g. email
>     } elsif {
>     if ($severity eq "WARNING") {
>         # put your code to handle Warnings here e.g. let it drop to 
> print_log
>     } elsif {
>     if ($severity eq "NOTICE") {
>         # put your code to handle Notices here
>     } elsif {
>     if ($severity eq "INFORMATIONAL") {
>         # put your code to handle Informational messages here
>     } elsif {
>     if ($severity eq "DEBUG") {
>         # put your code to handle Debug messages here
>     }
>
>     # catch-all to at least put it to the print log
>
>     print_log("$Severity: , $category - $message");
>
> }
>
> </snip>
>
> I suggest we put this in handy_utilities.pl so people aren't messing 
> with mh.pl, but maybe there is a better place, like perhaps its own .pm
>
> 3) Modules should then just call handle_log directly, or, we could 
> parameterise this further by having an mh.ini parameter like;
> <snip>
>
> Tasmota_HTTP_Send_Fail_Severity = ALERT
>
> </snip>
>
> And in the module something like;
>
> <snip>
>
> my $send_fail_sev = $::config_parms{Tasmota_HTTP_Send_Fail_Severity};
> if (!defined $send_fail_sev) {
>     $send_fail_sev = "ERROR";
> }
> # when the http fails
> handle_log("Failed to send to $item_name", $send_fail_sev, "HTTP send ");
>
> </snip>
>
> Could we drop this in instead of print_log?
>
> Have we missed anything?
>
> Giles
>
>
>
>
> ________________________________________________________
> To unsubscribe from this list, go to: https://lists.sourceforge.net/lists/listinfo/misterhouse-users
>

________________________________________________________
To unsubscribe from this list, go to: https://lists.sourceforge.net/lists/listinfo/misterhouse-users