Don't fail completely when PowerManager.init/1 raises #259
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When `PowerManager.init/1` implementations fail, supervision restarts GenServers like expected. However, `init/1` really isn't supposed to fail and when it does, it has the effect of propogating failures all the way up which eventually takes down VintageNet. While this is almost certainly a programming error, the result is particularly harsh. To better support debugging this issue, this commit logs the error and disables the power manager. The downside to this is that if there's a transient that would have been fixed by a restart, that no longer happens and perhaps the network won't work. While this isn't good, devices that require network connections to function need to have a "watchdog" that verifies that there's a network connection anyway. That logic should catch this.
mattludwigs
approved these changes
Nov 19, 2020
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When
PowerManager.init/1implementations fail, supervision restartsGenServers like expected. However,
init/1really isn't supposed tofail and when it does, it has the effect of propogating failures all the
way up which eventually takes down VintageNet. While this is almost
certainly a programming error, the result is particularly harsh.
To better support debugging this issue, this commit logs the error and
disables the power manager.
The downside to this is that if there's a transient that would have been
fixed by a restart, that no longer happens and perhaps the network won't
work. While this isn't good, devices that require network connections
to function need to have a "watchdog" that verifies that there's a
network connection anyway. That logic should catch this.