With the latest Golang Docker base image we are using the new gpg
version 2.4 is now being installed in the lnd Docker base image.
Apparently the expected value for the --keyring flag is just a file name
and not an absolute path. The path of the file is indicated either by
the $HOME environment variable or the --homedir flag. It looks like 2.4
now finally stopped supporting an absolute path in the --keyring flag
and we need to update our gpg command to make the script work again.
This should be backward compatible and still work on older versions of
gpg.
Schema for AMP invocies.
AMP invoices can be paid multiple times and each payment to an AMP invoice
is identified by a `set_id`.
The A in AMP stands for `Atomic`. All the htlcs belonging to the same
AMP payment (share the same set_id) will be resolved at the same time
with the same result: settled/canceled.
AMP invoices do not have an "invoice preimage". Instead, each htcl has
its own hash/preimage. When a new htlc is added the hash for that htlc
is attached to it. When all the htlcs of a set_id have been received we
are able to compute the preimage for each one of them.
Set of queries to deal with invoices. A couple of things to take into
account:
- Because the queries are not rewritten at runtime, we cannot have a
generic `INSERT` with different tuples.
- Because the queries are not rewritten at runtime, we cannot build
one query with only the filters that matter for that queries. The
two options are a combinatorial approach (a new query for every
permutation) or a generic query using the pattern
```
SELECT *
FROM table
WHERE (
-- Can be read as:
-- Match the filter 1 value if filter_1 != nil
column_1 >= sqlc.narg('filter_1') OR
sqlc.narg('filter_1') IS NULL
) AND (
column_2 >= sqlc.narg('filter_2') OR
sqlc.narg('filter_2') IS NULL
) ...
```
This is the schema for "ordinal" BOLT11 invoices.
The invoices table aims to keep an entry for each invoice, BOLT11 or not,
that will be supported.
Invoice related HTLCs will be stored in a separete table than forwarded
htlcs.
SQLite does not support `SEQUENCE`. We achieve atomic autoincrementals
using primary keys with autoincrement/serial. An invoice `AddIndex`
translates to `invoices(id)` while `SettleIndex` is `invoice_payments(id)`.
sqlc is a tool that generates fully type-safe idiomatic code from SQL.
The result is Go code can then used execute the queries in the database.
The noraml flow looks like:
- The developer write some sql that will update the schema in the
database: new tables, indices, etc
- The developer updates the set of queries that will use the new schema.
- `sqlc` generates type-safe interfaces to those queries.
- The developer can then write application code that calls the methods
generated by sqlc.
The tool configuration needs to live in the repo's root and its name is
`sqlc.yaml`.
LND will support out of the box sqlite and postgres. The sql code needs to
be (almost) the same for both engines, so we cannot use custom functions
like `ANY` in postgres.
The SQLC config file needs to define what is the target engine, we will
set postgres but the generated code can be executed by sqlite too.
In some specific cases, we will `match and replace` some sql lines to be
sure the table definitions are valid for the targeted engine.
The spec allows the final HTLC value and CLTV expiry to exceed
the value and expiry specified in the payload of the last hop
of the onion packet. We were over-restricting it to require
that it matches exactly.
As new pending channels will be tracked in the following commits, the
`newChannels` is now renamed to `newActiveChannel` to explicitly refer
to active, non-pending channels.
