# Changelog
All notable changes to this project will be documented in this file.

The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/)
and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).

## [Unreleased]

### Added

- Lightningd: add support for `signet` networks using the `--network=signet` or `--signet` startup option
- JSON API: `listfunds` now returns also `funding_output` for `channels`
- plugins: plugins can now suggest `lightning-cli` default to -H for responses.
- Plugin: new notification `forward_event` offered/settled/failed/local_failed.
- contrib: new `bootstrap-node.sh` to connect to random mainnet nodes.
- Protocol: `--enable-experimental-features` adds gossip query extensions
  aka https://github.com/lightningnetwork/lightning-rfc/pull/557

### Changed

- JSON API: `close` optional arguments have changed: it now defaults to unilateral close after 48 hours.
- build: now requires `python3-mako` to be installed, i.e. `sudo apt-get install python3-mako`
- plugins: if the config directory has a `plugins` subdirectory, those are loaded.
- plugins: a new notification type `invoice_payment` (sent when an invoice is paid) has been added
- plugins: a new 'channel_opened' notification type is added, which is emitted when a peer succesfully funds a channel to us
- rpc: a new rpc command is added, `plugin`. It allows one to manage plugins without restarting `lightningd`.
- plugins: a new boolean field is added to the `init`'s `configuration`, `startup`. It allows a plugin to know if it has been started on `lightningd` startup.
- plugins: a new boolean field can be added to a plugin manifest, `dynamic`. It allows a plugin to tell if it can be started or stopped "on-the-fly".
- lightningd: check bitcoind version when setup topology and confirm the version not older than v0.15.0.
- startup: space out reconnections on startup if we have more than 5 peers.
- JSON API: `listforwards` includes the 'payment_hash' field.
- plugins: now always run from the `lightning-dir` for easy local storage.

### Deprecated

Note: You should always set `allow-deprecated-apis=false` to test for
changes.

- plugins: using startup-relative paths for `plugin` and `plugin-dir`: they're now relative to `lightning-dir`.

### Removed

### Fixed

- Plugin: `pay` no longer crashes on timeout.
- Plugin: `disconnect` notifier now called if remote side disconnects.
- channeld: ignore, and simply try reconnecting if lnd sends "sync error".
- Protocol: we now correctly ignore unknown odd messages.
- wallet: We will now backfill blocks below our wallet start height on demand when we require them to verify gossip messages. This fixes an issue where we would not remove channels on spend that were opened below that start height because we weren't tracking the funding output.
- Detect when we're still syncing with bitcoin network: don't send or receive
  HTLCs or allow `fundchannel`.

### Security

## [0.7.1] - 2019-06-29: "The Unfailing Twitter Consensus Algorithm"

This release named by (C-Lightning Core Team member) Lisa Neigut @niftynei.

### Added

- Protocol: we now enforce `option_upfront_shutdown_script` if a peer negotiates it.
- JSON API: New command `setchannelfee` sets channel specific routing fees.
- JSON API: new withdraw methods `txprepare`, `txsend` and `txdiscard`.
- JSON API: add three new RPC commands: `fundchannel_start`, `fundchannel_complete` and `fundchannel_cancel`. Allows a user to initiate and complete a channel open using funds that are in a external wallet.
- Plugin: new hooks `db_write` for intercepting database writes, `invoice_payment` for intercepting invoices before they're paid, `openchannel` for intercepting channel opens, and `htlc_accepted` to decide whether to resolve, reject or continue an incoming or forwarded payment..
- Plugin: new notification `warning` to report any `LOG_UNUSUAL`/`LOG_BROKEN` level event.
- Plugin: Added a default plugin directory : `lightning_dir/plugins`. Each plugin directory it contains will be added to lightningd on startup.
- Plugin: the `connected` hook can now send an `error_message` to the rejected peer.
- JSON API: `newaddr` outputs `bech32` or `p2sh-segwit`, or both with new `all` parameter (#2390)
- JSON API: `listpeers` status now shows how many confirmations until channel is open (#2405)
- Config: Adds parameter `min-capacity-sat` to reject tiny channels.
- JSON API: `listforwards` now includes the time an HTLC was received and when it was resolved. Both are expressed as UNIX timestamps to facilitate parsing (Issue [#2491](https://github.com/ElementsProject/lightning/issues/2491), PR [#2528](https://github.com/ElementsProject/lightning/pull/2528))
- JSON API: `listforwards` now includes the local_failed forwards with failcode (Issue [#2435](https://github.com/ElementsProject/lightning/issues/2435), PR [#2524](https://github.com/ElementsProject/lightning/pull/2524))
- DB: Store the signatures of channel announcement sent from remote peer into DB, and init channel with signatures from DB directly when reenable the channel.
(Issue [#2409](https://github.com/ElementsProject/lightning/issues/2409))
- JSON API: `listchannels` has new fields `htlc_minimum_msat` and `htlc_maximum_msat`.

### Changed

- Gossip: we no longer compact the `gossip_store` file dynamically, due to lingering bugs.  Restart if it gets too large.
- Protocol: no longer ask for entire gossip flood from peers, unless we're missing gossip.
- JSON API: `invoice` expiry defaults to 7 days, and can have s/m/h/d/w suffixes.
- Config: Increased default amount for minimal channel capacity from 1k sat to 10k sat.
- JSON API: A new parameter is added to `fundchannel`, which now accepts an utxo array to use to fund the channel.
- Build: Non-developer builds are now done with "-Og" optimization.
- JSON API: `pay` will no longer return failure until it is no longer retrying; previously it could "timeout" but still make the payment.
- JSON API: the command objects that `help` outputs now contain a new string field : `category` (can be "bitcoin", "channels", "network", "payment", "plugins", "utility", "developer" for native commands, or any other new category set by a plugin).
- Plugin: a plugin can now set the category of a newly created RPC command. This possibility has been added to libplugin.c and pylightning.
- lightning-cli: the human readable help is now more human and more readable : commands are sorted alphabetically and ordered by categories.

### Deprecated

Note: You should always set `allow-deprecated-apis=false` to test for
changes.

- JSON API: `newaddr` output field `address`: use `bech32` or `p2sh-segwit` instead.

### Removed

- JSON RPC: `global_features` and `local_features` fields and `listchannels`' `flags` field.  (Deprecated since 0.6.2).
- pylightning: Remove RPC support for c-lightning before 0.6.3.

### Fixed

- Protocol: reconnection during closing negotiation now supports
  `option_data_loss_protect` properly.
- `--bind-addr=<path>` fixed for nodes using local sockets (eg. testing).
- Unannounced local channels were forgotten for routing on restart until reconnection occurred.
- lightning-cli: arguments containing `"` now succeed, rather than causing JSON errors.
- Protocol: handle lnd sending more messages before `reestablish`; don't fail channel, and handle older lnd's spurious empty commitments.
- Fixed `fundchannel` crash when we have many UTXOs and we skip unconfirmed ones.
- lightningd: fixed occasional hang on `connect` when peer had sent error.
- JSON RPC: `decodeinvoice` and `pay` now handle unknown invoice fields properly.
- JSON API: `waitsendpay` (PAY_STOPPED_RETRYING) error handler now returns valid JSON
- protocol: don't send multiple identical feerate changes if we want the feerate higher than we can afford.
- JSON API: `stop` now only returns once lightningd has released all resources.

### Security

## [0.7.0] - 2019-02-28: "Actually an Altcoin"

This release named by Mark Beckwith @wythe.

### Added

- plugins: fully enabled, and ready for you to write some!
- plugins: `pay` is now a plugin.
- protocol: `pay` will now use routehints in invoices if it needs to.
- build: reproducible source zipfile and Ubuntu 18.04.1 build.
- JSON API: New command `paystatus` gives detailed information on `pay` commands.
- JSON API: `getroute`, `invoice`, `sendpay` and `pay` commands `msatoshi`
  parameter can have suffixes `msat`, `sat` (optionally with 3 decimals) or `btc`
  (with 1 to 11 decimal places).
- JSON API: `fundchannel` and `withdraw` commands `satoshi`
  parameter can have suffixes `msat` (must end in `000`), `sat` or `btc`
  (with 1 to 8 decimal places).
- JSON API: `decodepay`, `getroute`, `sendpay`, `pay`, `listpeers`, `listfunds`, `listchannels` and
  all invoice commands now return an `amount_msat` field which has an `msat` suffix.
- JSON API: `listfunds` `channels` now has `_msat` fields for each existing raw amount field, with `msat` suffix.
- JSON API: `waitsendpay` now has an `erring_direction` field.
- JSON API: `listpeers` now has a `direction` field in `channels`.
- JSON API: `listchannels` now takes a `source` option to filter by node id.
- JSON API: `getroute` `riskfactor` argument is simplified; `pay` now defaults to setting it to 10.
- JSON API: `sendpay` now takes a `bolt11` field, and it's returned in `listpayments` and `waitsendpay`.
- JSON API: `fundchannel` and `withdraw` now have a new parameter `minconf` that limits coinselection to outputs that have at least `minconf` confirmations (default 1). (#2380)
- JSON API: `listfunds` now displays addresses for all outputs owned by the wallet (#2387)
- JSON API: `waitsendpay` and `sendpay` output field `label` as specified by `sendpay` call.
- JSON API: `listpays` command for higher-level payment view than `listpayments`, especially important with multi-part-payments coming.
- JSON API: `listpayments` is now `listsendpays`.
- lightning-cli: `help <cmd>` finds man pages even if `make install` not run.
- pylightning: New class 'Millisatoshi' can be used for JSON API, and new '_msat' fields are turned into this on reading.

### Changed

- protocol: `option_data_loss_protect` is now enabled by default.
- JSON API: The `short_channel_id` separator has been changed to be `x` to match the specification.
- JSON API: `listpeers` now includes `funding_allocation_msat`, which returns a map of the amounts initially funded to the channel by each peer, indexed by channel id.
- JSON API: `help` with a `command` argument gives a JSON array, like other commands.
- JSON API: `sendpay` `description` parameter is renamed `label`.
- JSON API: `pay` now takes an optional `label` parameter for labelling payments, in place of never-used `description`.
- build: we'll use the system libbase58 and libsodium if found suitable.

### Deprecated

Note: You should always set `allow-deprecated-apis=false` to test for
changes.

We recommend that you transition to the reading the new JSON `_msat`
fields for your own sanity checking, and that you similarly
provide appropriate suffixes for JSON input fields.

- JSON API: `short_channel_id` fields in JSON commands with `:` separators (use `x` instead).
- JSON API: `pay` `description` is deprecated, as is support for BOLT11 strings using `h`.
- JSON API: `sendpay` parameter `description` and `waitsendpay` and `sendpay` output fields `description` (now `label`).
- JSON API: `listpayments` has been deprecated (you probably want `listpays`)

### Removed

- JSON API: the `waitsendpay` command error return no longer includes `channel_update`

### Fixed

- Protocol: handling `query_channel_range` for large numbers of blocks
  (eg. 4 billion) was slow due to a bug.
- Fixed occasional deadlock with peers when exchanging huge amounts of gossip.
- Fixed a crash when running in daemon-mode due to db filename overrun (#2348)
- Handle lnd sending premature 'funding_locked' message when we're expected 'reestablish';
  we used to close channel if this happened.
- Cleanup peers that started opening a channel, but then disconnected. These
  would leave a dangling entry in the DB that would cause this peer to be
  unable to connect. (PR #2371)
- You can no longer make giant unpayable "wumbo" invoices.
- CLTV of total route now correctly evaluated when finding best route.
- `riskfactor` arguments to `pay` and `getroute` now have an effect.
- Fixed the version of bip32 private_key to BIP32_VER_MAIN_PRIVATE: we used
  BIP32_VER_MAIN_PRIVATE for bitcoin/litecoin mainnet, and BIP32_VER_TEST_PRIVATE
  for others. (PR #2436)

### Security

## [0.6.3] - 2019-01-09: "The Smallblock Conspiracy"

This release named by @molxyz and [@ctrlbreak](https://twitter.com/ctrlbreak).

### Added

- JSON API: New command `check` checks the validity of a JSON API call without running it.
- JSON API: `getinfo` now returns `num_peers` `num_pending_channels`,
  `num_active_channels` and `num_inactive_channels` fields.
- JSON API: use `\n\n` to terminate responses, for simplified parsing (pylightning now relies on this)
- JSON API: `fundchannel` now includes an `announce` option, when false it will keep channel private. Defaults to true.
- JSON API: `listpeers`'s `channels` now includes a `private` flag to indicate if channel is announced or not.
- JSON API: `invoice` route hints may now include private channels if you have no public ones, unless new option `exposeprivatechannels` is false.
- Plugins: experimental plugin support for `lightningd`, including option passthrough and JSON-RPC passthrough.

### Changed

- JSON API: `pay` and `decodepay` accept and ignore `lightning:` prefixes.
- pylightning: Allow either keyword arguments or positional arguments.
- JSON-RPC: messages are now separated by 2 consecutive newlines.
- JSON-RPC: `jsonrpc`:`2.0` now included in json-rpc command calls. complies with spec.

### Deprecated

Note: You should always set `allow-deprecated-apis=false` to test for
changes.

- pylightning: Support for pre-2-newline JSON-RPC (<= 0.6.2 lightningd) is deprecated.

### Removed

- option_data_loss_protect is now only offered if EXPERIMENTAL_FEATURES is enabled, since it seems incompatible with lnd and has known bugs.

### Fixed

- JSON API: uppercase invoices now parsed correctly (broken in 0.6.2).
- JSON API: commands are once again read even if one hasn't responded yet (broken in 0.6.2).
- Protocol: allow lnd to send `update_fee` before `funding_locked`.
- Protocol: fix limit on how much funder can send (fee was 1000x too small)
- Protocol: don't send invalid onion errors if peer says onion was bad.
- Protocol: don't crash when peer sends a 0-block-expiry HTLC.
- pylightning: handle multiple simultanous RPC replies reliably.
- build: we use `--prefix` as handed to `./configure`

### Security


## [0.6.2] - 2018-10-20: "The Consensus Loving Nasal Daemon"

This release named by practicalswift.

### Added

- JSON API: `listpeers` has new field `scratch_txid`: the latest tx in channel.
- JSON API: `listpeers` has new array `htlcs`: the current live payments.
- JSON API: `listchannels` has two new fields: `message_flags` and `channel_flags`. This replaces `flags`.
- JSON API: `invoice` now adds route hint to invoices for incoming capacity (RouteBoost), and warns if insufficient capacity.
- JSON API: `listforwards` lists all forwarded payments, their associated channels, and fees.
- JSON API: `getinfo` shows forwarding fees earnt as `msatoshi_fees_collected`.
- Bitcoind: more parallelism in requests, for very slow nodes.
- Testing: fixed logging, cleaner interception of bitcoind, minor fixes.
- Protocol: we set and handle the new `htlc_maximum_msat` channel_update field.

### Changed

- Protocol: `channel_update` sent to disable channel only if we reject an HTLC.
- Protocol: we don't send redundant `node_announcement` on every new channel.
- Config: config file can override `lightning-dir` (makes sense with `--conf`).
- Config: `--conf` option is now relative to current directory, not `lightning-dir`.
- lightning-cli: `help <cmd>` prints basic information even if no man page found.
- JSON API: `getinfo` now reports global statistics about forwarded payments, including total fees earned and amounts routed.

### Deprecated

Note: You should always set `allow-deprecated-apis=false` to test for
changes.

- JSON RPC: `listchannels`' `flags` field. This has been split into two fields, see Added.
- JSON RPC: `global_features` and `local_features` fields: use `globalfeatures` and `localfeatures` as per BOLT #1.

### Removed

- JSON API: the optional 'seed' parameter to `getroute` was removed.

### Fixed

- Startup: more coherent complaint if daemon already running.
- Lightningd: correctly save full HTLCs across restarts; fixup old databases.
- JSON RPC: `getinfo` now shows correct Tor port.
- JSON RPC: `ping` now works even after one peer fails to respond.
- JSON RPC: `getroute` `fuzzpercent` and `pay` `maxfeepercent` can now be > 100.
- JSON RPC: `riskfactor` in `pay` and `getroute` no longer always treated as 1.
- JSON-RPC: `listpeers` was always reporting 0 for all stats.
- JSON RPC: `withdraw all` says `Cannot afford transaction` if you have
             absolutely no funds, rather than `Output 0 satoshis would be dust`.
- Protocol: don't send gossip about closed channels.
- Protocol: fix occasional deadlock when both peers flood with gossip.
- Protocol: fix occasional long delay on sending `reply_short_channel_ids_end`.
- Protocol: re-send `node_announcement` when address/alias/color etc change.
- Protocol: multiple HTLCs with the same payment_hash are handled correctly.
- Options: 'autotor' defaults to port 9051 if not specified.

### Security

## [0.6.1] - 2018-09-11: "Principled Opposition To Segwit"

This release named by ZmnSCPxj.

### Added

- Protocol: gossipd now deliberately delays spamming with `channel_update`.
- Protocol: liveness ping when we commit changes but peer is idle: speeds up
  failures and reduces forced closures.
- Protocol: `option_data_loss_protect` now supported to protect peers
  against being out-of-date.
- JSON API: Added description to invoices and payments (#1740).
- JSON API: `getinfo` has new fields `alias` and `color`.
- JSON API: `listpeers` has new fields `global_features` and `local_features`.
- JSON API: `listnodes` has new field `global_features`.
- JSON API: `ping` command to send a ping to a connected peer.
- JSON API: `feerates` command to retrieve current fee estimates.
- JSON API: `withdraw` and `fundchannel` can be given manual feerate.
- Config: `--conf` option to set config file.
- Documentation: Added CHANGELOG.md
- pylightning: RpcError now has `method` and `payload` fields.
- Sending lightningd a SIGHUP will make it reopen its `log-file`, if any.

### Changed

- Protocol: Fee estimates are now smoothed over time, to avoid sudden jumps.
- Config: You can only announce one address if each type (IPv4, IPv6,
  TORv2, TORv3).
- lightning-cli: the help command for a specific command now runs the
  `man` command.
- HSM: The HSM daemon now maintains the per-peer secrets, rather than
  handing them out.  It's still lax in what it signs though.
- connectd: A new daemon `lightning_connectd` handles connecting
  to/from peers, instead of `gossipd` doing that itself. `lightning_openingd` now
  handles peers immediately, even if they never actually open a channel.
- Test: `python-xdist` is now a dependency for tests.
- Logging: JSON connections no longer spam debug logs.
- Routing: We no longer consider channels that are not usable either because of
  their capacity or their `htlc_minimum_msat` parameter (#1777)
- We now try to connect to all known addresses for a peer, not just
  the one given or the first one announced.
- Crash logs are now placed one-per file like `crash.log.20180822233752`
- We will no longer allow withdrawing funds or funding channels if we
  do not have a fee estimate (eg. bitcoind not synced); use new `feerate` arg.

### Deprecated

### Removed

- JSON API: `listpeers` results no long have `alias` and `color` fields;
  they're in `listnodes` (we used to internally merge the information).
- JSON API: `listpeers` will never have `state` field (it accidentally
  used to exist and set to `GOSSIPING` before we opened a channel).
  `connected` will indicate if we're connected, and the `channels`
  array indicates individual channel states (if any).
- Config: `default-fee-rate` is no longer available; use explicit `feerate`
  option if necessary.
- Removed all Deprecated options from 0.6.

### Fixed

- Protocol: `node_announcement` multiple addresses are correctly ordered and uniquified.
- Protocol: if we can't estimate feerate, be almost infinitely
  tolerant of other side setting fees to avoid unilateral close.
- JSON API: `listnodes`: now displays node aliases and colors even if they
  don't advertise a network address
- JSON API: `fundchannel all`: now restricts to 2^24-1 satoshis rather than failing.
- JSON API: `listnodes`: now correctly prints `addresses` if more than
  one is advertised.
- Config: `bind-addr` of a publicly accessible network address was announced.
- When we reconnect and have to retransmit failing HTLCs, the errors weren't
  encrypted by us.
- `lightningd_config` man page is now installed by `make install`.
- Fixed crash when shutting down during opening a channel (#1737)
- Don't lose track of our own output when applying penalty transaction (#1738)
- Protocol: `channel_update` inside error messages now refers to correct channel.
- Stripping type prefix from `channel_update`s that are nested in an onion reply
  to be compatible with eclair and lnd (#1730).
- Failing tests no longer delete the test directory, to allow easier debugging
  (Issue: #1599)

### Security

## [0.6] - 2018-06-22: "I Accidentally The Smart Contract"

In the prehistory of c-lightning, no changelog was kept.  But major
JSON API changes are tracked.

This release named by Fabrice Drouin.

### Deprecated

Note: You should always set `allow-deprecated-apis=false` to test for
changes.

- Config: `port`.  Use `addr=:<portnum>`.
- Config: `ipaddr`.  Use `addr`.
- Config: `anchor-confirms`.  Use `funding-confirms`.
- Config: `locktime-blocks`.  Use `watchtime-blocks`.
- Protocol: on closing we allow out-of-range offers, prior to spec fix
  2018-01-30 ("BOLT 2: order closing-signed negotiation by making
  funder send first." `90241d9cf60a598eac8fd839ac81e4093a161272`)
- JSON API: `listinvoice` command.  Use `listinvoices`.
- JSON API: invoice result fields `paid_timestamp` and `expiry_time`.  Use
  `paid_at` and `expires_at`.
- JSON API: `invoice` command field `fallback`.  Use `fallbacks`.
- JSON API: `decodepay` result fields `timestamp` and `fallback`.  Use
  `created_at` and `fallbacks`.
- JSON API: payment result fields `timestamp`.  Use `created_at`.
- JSON API: `getinfo` result field `port`.  Use `binding` and `address` arrays.
- JSON API: `getlog` result field `creation_time`.  Use `created_at`.
- JSON API: `getpeers` result field `channel_reserve_satoshis`.  Use `their_channel_reserve_satoshis`.
- JSON API: `getpeers` result field `to_self_delay`.  Use `their_to_self_delay`.

## Older versions

There predate the BOLT specifications, and are only of vague historic interest:

1. [0.1] - 2015-08-08: "MtGox's Cold Wallet" (named by Rusty Russell)
2. [0.2] - 2016-01-22: "Butterfly Labs' Timely Delivery" (named by Anthony Towns)
3. [0.3] - 2016-05-25: "Nakamoto's Genesis Coins" (named by Braydon Fuller)
4. [0.4] - 2016-08-19: "Wright's Cryptographic Proof" (named by Christian Decker)
5. [0.5] - 2016-10-19: "Bitcoin Savings & Trust Daily Interest" (named by Glenn Willen)
6. [0.5.1] - 2016-10-21
7. [0.5.2] - 2016-11-21: "Bitcoin Savings & Trust Daily Interest II"

[Unreleased]: https://github.com/ElementsProject/lightning/compare/v0.7.1...HEAD
[0.7.1]: https://github.com/ElementsProject/lightning/releases/tag/v0.7.1
[0.7.0]: https://github.com/ElementsProject/lightning/releases/tag/v0.7.0
[0.6.3]: https://github.com/ElementsProject/lightning/releases/tag/v0.6.3
[0.6.2]: https://github.com/ElementsProject/lightning/releases/tag/v0.6.2
[0.6.1]: https://github.com/ElementsProject/lightning/releases/tag/v0.6.1
[0.6]: https://github.com/ElementsProject/lightning/releases/tag/v0.6
[0.5.2]: https://github.com/ElementsProject/lightning/releases/tag/v0.5.2-2016-11-21
[0.5.1]: https://github.com/ElementsProject/lightning/releases/tag/v0.5.1-2016-10-21
[0.5]: https://github.com/ElementsProject/lightning/releases/tag/v0.5-2016-10-19
[0.4]: https://github.com/ElementsProject/lightning/releases/tag/v0.4-2016-08-19
[0.3]: https://github.com/ElementsProject/lightning/releases/tag/v0.3-2016-05-26
[0.2]: https://github.com/ElementsProject/lightning/releases/tag/v0.2-2016-01-22
[0.1]: https://github.com/ElementsProject/lightning/releases/tag/v0.1-2015-08-08
