We used to only probe for a 10sat amount, which allows us to test
basic reachability, but it doesn't say much about whether we can
actually pay for something reasonable, so this fixes that.
This may require the following SQL statement to be applied to the
database if you are upgrading from a prior version:
```sql
ALTER TABLE probes ADD amount INTEGER;
```
This is not required if you start with a new database.
This just tries all prefixes of a route to the given node, returning a failure
as soon as it hits the channel that got the payment stuck.
Signed-off-by: Christian Decker <decker.christian@gmail.com>
Since `probe` may take a while, or hang altogether we better make it async so
we can run multiple ones in parallel. The next step is to have a sweeper
thread that just checks all pending probes.
Signed-off-by: Christian Decker <decker.christian@gmail.com>
It was returning `null` and we'd have to check the logs or the DB for the
result. This makes it just a bit easier to see what happens.
Signed-off-by: Christian Decker <decker.christian@gmail.com>
This is a plugin that regularly probes the network by sending a random payment
to a random destination. These do not succeed, since we randomly selected the
`payment_hash`, but can still give us a lot of insight into the network
health.
The plugin stores its results in a `sqlite3` database for later inspection.
Signed-off-by: Christian Decker <decker.christian@gmail.com>
