[pbs-devel] [PATCH proxmox-backup 1/1] backup-proxy and parallel_handler: Improved errors when panics occur and the panic message is a formatted (not static) string. This worked already for &str literals, but not for Strings.

[Laurențiu Leahu-Vlăducu]

Thanks for the review! I sent a v2 which includes your suggestions.

On 21.01.25 11:56, Gabriel Goller wrote:
> On 21.01.2025 10:36, Laurențiu Leahu-Vlăducu wrote:
>> diff --git a/src/bin/proxmox-backup-proxy.rs b/src/bin/proxmox-backup- 
>> proxy.rs
>> index ce1be1c0..a7dab4ac 100644
>> --- a/src/bin/proxmox-backup-proxy.rs
>> +++ b/src/bin/proxmox-backup-proxy.rs
>> @@ -424,7 +424,10 @@ async fn run_task_scheduler() {
>>         match schedule_tasks().catch_unwind().await {
>>             Err(panic) => match panic.downcast::<&str>() {
>>                 Ok(msg) => eprintln!("task scheduler panic: {msg}"),
>> -                Err(_) => eprintln!("task scheduler panic - unknown 
>> type"),
>> +                Err(panic) => match panic.downcast::<String>() {
>> +                    Ok(msg) => eprintln!("task scheduler panic: {msg}"),
>> +                    Err(_) => eprintln!("task scheduler panic - 
>> cannot show error message due to unknown error type")
> 
> AFAIK this gets called after the logging init, so we can use
> tracing::error for the log messages here.
> 
>> +                }
>>             },
>>             Ok(Err(err)) => eprintln!("task scheduler failed - {err:?}"),
>>             Ok(Ok(_)) => {}
>> diff --git a/src/tools/parallel_handler.rs b/src/tools/ 
>> parallel_handler.rs
>> index 17f70179..429a1f8b 100644
>> --- a/src/tools/parallel_handler.rs
>> +++ b/src/tools/parallel_handler.rs
>> @@ -140,7 +140,13 @@ impl<I: Send + 'static> ParallelHandler<I> {
>>                         "thread {} ({}) panicked: {}",
>>                         self.name, i, panic_msg
>>                     )),
>> -                    Err(_) => msg_list.push(format!("thread {} ({}) 
>> panicked", self.name, i)),
>> +                    Err(panic) => match panic.downcast::<String>() {
>> +                        Ok(panic_msg) => msg_list.push(format!(
>> +                            "thread {} ({}) panicked: {}",
>> +                                self.name, i, panic_msg
>> +                        )),
>> +                        Err(_) => msg_list.push(format!("thread {} 
>> ({}) panicked", self.name, i))
> 
> A few variables can be be inlined here.
> 
> The downcast part looks ok to me.
> Please keep the commit message title under 72 characters.
> 
> Thanks!