Changelog-Added: The MPP presplit modifier splits large payments into 10k satoshi parts to maximize chances of performing the payment and to obfuscate the overall amount being sent.
As suggested during the paymod-03 review it is better to activate the new code
right away, and give users an escape hatch to use the legacy code instead. The
way I implemented it allows using either `legacypay` or `pay` and then set
`legacy` to switch to the other implementation.
Changelog-Added: JSON-RPC: The `pay` command now uses the new payment flow, the new `legacypay` command can be used to issue payment with the legacy code if required.
Suggested-by: Rusty Russell <@rustyrussell>
Suggested-by: ZmnSCPxj <@zmnscpxj>
This commit collects the changes required to the tests caused by the changes
to the `pay` and `paystatus` commands. They are also rather good hints as to
what these changes entail.
These are primarily the fee and cltv constraints that we need to keep up to
date in order to give modifiers a correct view of what is and what isn't
allowed.
We can have quite detailed information about our local channels, so call
`listpeers` before the `getroute` call on the root payment, to seed that
information in the channel_hints.
Since we end up consolidating some of the return values for `pay` and
`paystatus` and change the public interface we need to add the compatibility
flag and guard the switchover behind it.
We need to keep them around so we can inspect them later. We'll also need a
background cleanup every once in a while to free some memory. More on that in
a future commit.
This is likely a bit of overkill for this type of functionality, but it is a
nice first use-case of how functionality can be compartmentalized into
modifiers. If makes swapping retry mechanisms in and out really simple.
This commit can be reverted/skipped once we have implemented all the logic and
have feature parity with the normal `pay`. It's main purpose is to expose the
unfinished functionality to test it, without completely breaking the existing
`pay` command.
And the percentage of the initial amount, not the constently increasing
one !
Changelog-Fixed: pay: we now respect maxfeepercent, even for tiny amounts.
Signed-off-by: Antoine Poinsot <darosior@protonmail.com>
The shadow route algorithm is extending the route randomly using channels
adjacent to the current destination, in the hope to create a plausible route
extension. However, instead of only retrieving the channels adjacent to the
destination it was retrieving all channels in the entire topology, and
selecting a random channel from there. This resulted in a very large request
for all channels being processed, and then mostly not being used, but also in
shadow extensions to the path which were not plausible (they didn't extend the
real path, just random edges). This is fixed by restricting the call to
`listchannels` to the channels with the current destination as source.
On my laptop retrieving all channels in the current mainnet takes
approximately 1.2 seconds, and given the geometric series expansion of the 50%
extension probability this indeed would result in an overhead of 1.2 seconds
to the `pay` command. In contrast specifying a source results in an overhead
of ~30ms.
So good news everyone, your pay commands just shaved 1.17 seconds off their
runtime.
Changelog-Changed: pay: Improved the performance of the `pay`-plugin by limiting the `listchannels` when computing the shadow route.
Changelog-Fixed: pay: The `pay`-plugin was generating non-contiguous shadow routes
Turns out that unnecessary: all callers can access the feature_set,
so make it much more like a normal primitive.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This is a common thing to do, so create a macro.
Unfortunately, it still needs the type arg, because the paramter may
be const, and the return cannot be, and C doesn't have a general
"(-const)" cast.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Before this patch we used to send `double`s over the wire by just
copying them. This is not portable because the internal represenation
of a `double` is implementation specific.
Instead of this, multiply any floating-point numbers that come from
the outside (e.g. JSONs) by 1 million and round them to integers when
handling them.
* Introduce a new param_millionths() that expects a floating-point
number and returns it multipled by 1000000 as an integer.
* Replace param_double() and param_percent() with param_millionths()
* Previously the riskfactor would be allowed to be negative, which must
have been unintentional. This patch changes that to require a
non-negative number.
Changelog-None
This adds helpers to start and send a jsonrpc request using json_stream
in order to benefit from the helpers.
This then simplifies existing plugins RPC requests by using json_stream
helpers.
Before this patch we used `int` for error codes. The problem with
`int` is that we try to pass it to/from wire and the size of `int` is
not defined by the standard. So a sender with 4-byte `int` would write
4 bytes to the wire and a receiver with 2-byte `int` (for example) would
read just 2 bytes from the wire.
To resolve this:
* Introduce an error code type with a known size:
`typedef s32 errcode_t`.
* Change all error code macros to constants of type `errcode_t`.
Constants also play better with gdb - it would visualize the name of
the constant instead of the numeric value.
* Change all functions that take error codes to take the new type
`errcode_t` instead of `int`.
* Introduce towire / fromwire functions to send / receive the newly added
type `errcode_t` and use it instead of `towire_int()`.
In addition:
* Remove the now unneeded `towire_int()`.
* Replace a hardcoded error code `-2` with a new constant
`INVOICE_EXPIRED_DURING_WAIT` (903).
Changelog-Changed: The waitinvoice command would now return error code 903 to designate that the invoice expired during wait, instead of the previous -2
Changelog-Fixed: Detect a previously non-permanent error (`final_cltv_too_soon`) that has been merged into a permanent error (`incorrect_or_unknown_payment_details`), and retry that failure case in `pay`.
