# CHANGELOG
# v5.0.0-rc.8
### Bug Fixes
* Fixes #250 `peer_host` not working. The `peer_host` was an experimental option that was never rally implemented and thus has been deprecated and the original feature has been now implemented using the `listen_addrs` feature and the new host resolution algorithm
### Changes
* `listen_addrs` is now the preferred way to configure the IP/Ports where Partisan will listen for connections. The new implementation allows for multiple different formats and coerces them to the `partisan:listen_addr()` type i.e. `#{ip => inet:ip_address(), port => 1..65535}`. The following example shows the different formats accepted by the option.
```erlang
{listen_addrs, [
"127.0.0.1:12345",
<<"127.0.0.1:12345">>,
{"127.0.0.1", "12345"},
{{127, 0, 0, 1}, 12345},
#{ip => "127.0.0.1", port => "12345"},
#{ip => <<"127.0.0.1">>, port => <<"12345">>},
#{ip => {127, 0, 0, 1}, port => 12345}
]},
```
* A new algorithm has been implemented to determine the listen address when `listen_addr` is not defined in the configuration. The algorithm uses `peer_ip` the Erlang nodename or `name` configuration option to extract the host from the name e.g. `HOST` in `mynode@HOST` and uses `inet:getaddr` to determine the IP Address.
# v5.0.0-rc.8
### Changes
* Performance improvements for `partisan:forward/2,3,4`.
# v5.0.0-rc.2
### Bug Fixes
* Fixes a bug in `partisan:spawn/2`
# v5.0.0-rc.1
### Bug Fixes
* Make sure a message forward to a local process never fails (restoring the original behaviour).
* Minor bug fixes
* Fixed type issues detected by Eqwalizer and Dialyzer
### Changes
* Readme Docs improvements
# v5.0.0-beta.24
* Removed eqwalizer from default profile
# v5.0.0-beta.23
### Bug Fixes
* Coerce `forward_options` configuration option to map format.
* Fix bug in merge of forward options on `partisan_pluggable_peer_service` module
* Test suite fixes
* Export missing `partisan:monitor_node/3` function.
* Fix a bug in `partisan_hyparview_peer_service_message` when Options are passed as list.
### Changes
* Remove unused module `partisan_promise_backend`
# v5.0.0-beta.22
### Bug Fixes
* Continued adding support for OTP.
* The OTP modules `sys`, `proc_lib` where patched (`partisan_sys`, `partisan_proc_lib`) so that they support the `partisan_remote_ref:t()` type and use the `partisan` module functions for finding, monitoring and sending messages instead of the native Erlang counterparts.
* OTP patched files are located in the priv directory and loaded dynamically by `rebar.config.script` based on the Erlang/OTP version being used.
* Patched the CT suites (`gen_server_SUITE`, `gen_statem_SUITE`, `gen_event_SUITE`) to test the partisan OTP modules. All tests passing except for some test cases that require not-yet implemented features like global and some `rpc` functions.
* Notice `global` is not yet supported by Partisan.
* Added support for Eqwalizer, and passed both Eqwalizer and Dialyzer checks
### Additions
* New improper list format for `partisan_remote_ref`. This deprecates the config option `remote_ref_as_uri` and adds `remote_ref_format` instead which accepts `improper_list` (the new default), `tuple` (the legacy format) and `uri` (also introduced in v5).
* Adds `partisan_erpc`. The patched version of the Erlang's `erpc` module.
# v5.0.0-beta.19
### Bug Fixes
* Fix implementation of `partisan_pluggable_peer_service_manager:sync_join/1`.
# v5.0.0-beta.18
### Bug Fixes
* Remove optimisation from `partisan:self/0` and add `partisan:self/1` which accepts the `cache` option making the use of th optimization to be explicit. Check the docs for the explanation.
* Fixed bug in `partisan:monitor/2` introduced in previous version.
# v5.0.0-beta.17
### Bug Fixes
* Fix bugs in `partisan_gen_statem` and `partisan_gen`
# v5.0.0-beta.16
### Bug Fixes
* Fix a bug in `partisan:send/2,3`
### Changes
* Ensure the membership channel (`partisan_membership`) exits and is properly configured.
# v5.0.0-beta.15
### Bug Fixes
* General bug fixes including:
* #121 updated_members should only accept a list of maps (an never a list of nodes)
* fix wrong calls to `self()` and `node()` as opposed to their partisan counterparts
* Fixed bugs in `partisan_monitor`
* Several bug fixes in the OTP implementation
* Several bug fixes in the CT suite
### Changes
* Changed signature of partisan_membership_strategy and the implementing modules; added API e.g. `join(state(), partisan:node_spec(), state())` is now ` join(partisan:node_spec(), state(), state())` which is more natural.
* Added partisan_membership_strategy API functions, so that pluggable manager can call these functions
* Some other naming changes to disambiguate e.g. membership -> members
* moved some opt types from partisan_monitor to partisan module
* Fixed missing of gen_ and partisan_gen function calls.
* Made `channel` options to be respected across the stack
* Added channel configuration to `partisan_monitor` calls.
* Added channel to OTP behaviours.
* The messages and the monitor signals will be sent using the configured channel.
* overloaded gen_server/statem functions to accept options including channel so that we do not add another function to the API
* store the Partisan opts in the process dict (again to avoid modifying our changed versions of the behaviours)
*
* Configuration parameters renaming. Several configuration parameters were renamed. Check `partisan_config` module description. The old parameters are still accepted but are renamed during startup.
* Deprecated the `partisan_peer_service_manager:myself` callback
* Fix `partisan_util` term encoding and renamed function; added compression option for encoding and for memberhip payload
### Additions
* Added the following modules:
* `partisan_supervisor` behaviour
* Added the following functions:
* `partisan:exit/2`
* `partisan:send/2`
* `partisan:send/3`
* `partisan:send_after/3`
* `partisan:send_after/4`
* `partisan:cancel_timer/1`
* `partisan:cancel_timer/2`
* Peer Service manager now allows subscribing to events per channel
* `partisan_peer_service_manager:on_up/3` accepting a channel
* `partisan_peer_service_manager:on_down/3` accepting a channel
# v5.0.0-beta.14
## API
#### Changes
* Several functions previously found in `partisan_util` are now in `partisan_peer_service_manager`.
- Types previously found in `partisan.hrl` are now defined and exported by the `partisan` module.
## Peer Membership
#### Fixes
* Several bug fixes in the following backends:
* `partisan_hyparview_peer_service_manager`
* `partisan_xbot_hyparview_peer_service_manager`
* `partisan_client_server_peer_service_manager`
* Fixes a bug in `partisan_plumbtree_broadcast` where not all the handlers were used.
* The configuration option `broadcast_start_exchange_limit` is now considered to refer to each handler i.e. a limit of `1` means Partisan will only allow one instance of a broadcast AAE exchange per handler (and not a single one in total).
## Peer Connection Management
#### Changes
* **Channel parallelism** can now be defined **per channel**
* `channels` configuration option is overloaded to allow the new configuration options while keeping backwards compatibility. Check the documentation for the new formats in [partisan_config](partisan_config.html).
* The `partisan:node_spec()` representation was changed:
* `parallelism` was removed
* `channels` was changed from a list of atoms or tuples to a the return of `partisan_config:get(channels)` i.e. a map.
* `parallelism` is now used as a default when the user doesn’t define a per channel parallelism.
* The `partisan` module now exports the new function `channel_opts/1` with returns the options for a given channel.
# v5.0.0-beta.13
## API
In general, the API was redesigned to concentrate all functions around two modules: `partisan` and `partisan_peer_service`.
#### Changes
* `partisan` module was repurposed as a replacement for the `erlang` module for use cases related to distribution e.g. `erlang:nodes/0` -> `partisan:nodes/0`.
* Several functions previously found in `partisan_peer_service`, `partisan_monitor` and `partisan_util` are now in this module:
* `partisan:broadcast/2`
* `partisan:cast_message/2`
* `partisan:cast_message/3`
* `partisan:cast_message/4`
* `partisan:default_channel/0`
* `partisan:demonitor/1`
* `partisan:demonitor/2`
* `partisan:disconnect_node/1`.
* `partisan:forward_message/2`
* `partisan:forward_message/3`
* `partisan:forward_message/4`
* `partisan:is_alive/0`
* `partisan:is_connected/1`
* `partisan:is_connected/2`
* `partisan:is_fully_connected/1`
* `partisan:is_local/1`
* `partisan:is_pid/1`
* `partisan:is_process_alive/1`
* `partisan:is_reference/1`
* `partisan:make_ref/0`
* `partisan:monitor/1`
* `partisan:monitor/2`
* `partisan:monitor/3`
* `partisan:monitor_node/2`
* `partisan:monitor_nodes/1`
* `partisan:monitor_nodes/2`
* `partisan:node/0`
* `partisan:node/1`
* `partisan:node_spec/0`
* `partisan:node_spec/1`
* `partisan:node_spec/2`
* `partisan:nodes/0`
* `partisan:nodes/1`
* `partisan:nodestring/0`
* `partisan:self/0`
* Added the following functions:
* `partisan_peer_service:broadcast_members/0`
* `partisan_peer_service:broadcast_members/1`
* `partisan_peer_service:cancel_exchanges/1`
* `partisan_peer_service:exchanges/0`
* `partisan_peer_service:exchanges/1`
* `partisan_peer_service:get_local_state/0`
* `partisan_peer_service:inject_partition/2`
* `partisan_peer_service:leave/1`
* `partisan_peer_service:member/1`
* `partisan_peer_service:members_for_orchestration/0`
* `partisan_peer_service:on_down/2`
* `partisan_peer_service:on_up/2`
* `partisan_peer_service:partitions/0`
* `partisan_peer_service:reserve/1`
* `partisan_peer_service:resolve_partition/1`
* `partisan_peer_service:update_members/1`
* Use of `partisan_peer_service:mynode/0` has been replaced by `partisan:node/0` to follow Erlang convention
* Use of `partisan_peer_service:myself/0` has been replaced by `partisan:node_spec/0` to disambiguate from `partisan:node/0`.
* Use of `Node` variable name for `node()` type (as opposed to `Name`) and `NodeSpec` for `node_spec()` (as opposed to `Node`) to disambiguate.
* Adde new module `partisan_rpc` that will provide and API that mirrors Erlangs `rpc` and `erpc` modules
* Added `partisan_remote_ref` to encapsulate the creation of reference and added an optional/alternative representation for encoded pids, references and registered names. The module offers all the functions to convert pids, references and names to/from Partisan encoded references.
* Alternative representation: In cases where lots of references are stored in process state, ets and specially where those are uses as keys, a binary format is preferable to the tuple format in order to save memory usage and avoid copying the term every time a message is send between processes. `partisan_remote_ref` represents an encoded reference as binary URI. This is controlled by the config option `remote_ref_as_uri` and `remote_ref_binary_padding` in case the resulting URIs are smaller than 65 bytes.
```erlang
1> partisan_remote_ref:from_term(self()).
{partisan_remote_reference,nonode@nohost,{partisan_process_reference,"<0.1062.0>"}}
2> partisan_config:set(remote_ref_as_uri, true).
ok
3> partisan_remote_ref:from_term(self()).
<<"partisan:pid:nonode@nohost:0.1062.0">>
4> partisan_config:set(remote_ref_binary_padding, true).
ok
5> partisan_remote_ref:from_term(self()).
<<"partisan:pid:nonode@nohost:0.1062.0:"...>>
```
## Peer Membership
#### Fixes
* Extracted the use of `state_orset` from `partisan_full_membership_strategy` into its own module `partisan_membership_set` which will allow the possibility to explore alternative data structures to manage the membership set.
* Introduced a membership prune operation to remove duplicate node specifications in the underlying `state_orset` data structure. This isto avoid an issue where a node will crash and restart with a different IP address e.g. when deploying in cloud orchestration platforms. As the membership set contains `node_spec()` objects which contain IP addresses we ended up with duplicate entries for the node. The prune operation tries to break ties between these duplicates at time of connection, trying to recognise when a node specification might be no longer valid forcing the removal of the spec from the set.
* Fixes several bugs related to the `leave` operation in `partisan_pluggable_peer_service_manager`:
* Added a missing call to update the membership set during leave
* Fixed a concurrency issue whereby on self leave the peer service server will restart before being able to sending the new state with the cluster peers and thus the node would remain as a member in all other nodes.
* Resolves an issue `partisan_plumtree_broadcast` where the `all_members` set was not updated when a member is removed.
* Resolves the issue where the `partisan_plumtree_broadcast` was not removing the local node from the broadcast member set.
* Gen Behaviours take new option `channel` if defined.
* Fixed implementation of `on_up` and `on_down` callback functions in `partisan_pluggable_peer_service_manager`
#### Changes
* Added function `partisan_peer_service_manager:member/1`
* Replaced the use of in-process sets in `plumtree_broadcast_backend` with an `ets` table for outstanding messages keeping the gen_server stack lean and avoiding garbage collection
## Peer Connection management
#### Fixes
* Fixes a bug where connections where not properly killed during a leave
* Split TLS options for client and server roles
* Removed `tls_options`
* Added `tls_client_options` and `tls_server_options`
#### Changes
* New module `peer_service_connections`:
* Replaces the former `peer_service_connections` process state data structure and the `partisan_connection_cache` module.
* As a result, the `partisan_connection_cache` module has been was removed.
* Checking connection status is now very fast and cheap. The implementation uses `ets` to handle concurreny. It leverages leverages `ets:update_counter/4`, `ets:lookup_element/3` and `ets:select_count/2` for fast access and to minimise copying data into the caller's process heap.
## Process and Peer Monitoring
#### Fixes
* A more complete/safe implementation of process monitoring in `partisan_monitor`.
* More robust implementation of monitors using the new subscription capabilities provided by `peer_service:on_up` and `peer_service:on_down` callback functions.
- monitor a node or all nodes
- use node monitors to signal a process monitor when the remote node is disconnected
- local cache of process monitor to ensure the delivery of DOWN signal when the connection to the process node is down.
- avoid leaking monitors
- new supervisor to ensure that `partisan_monitor` is restarted every time the configured `partisan_peer_service_manager` is restarted.
- re-implementation based on ets tables
- If using OTP25 the monitor gen_server uses the parallel signal optimisation by placing the process inbox data off heap
> #### NOTICE {: .warning}
>
> At the moment this only works for `partisan_pluggable_peer_service_manager` backend.
#### Changes
* New api in `partisan` module following the same name, signature and semantics of their `erlang` and `net_kernel` modules counterparts:
* `partisan:monitor/1`
* `partisan:monitor/2`
* `partisan:monitor/3`
* `partisan:monitor_node/2`
* `partisan:monitor_nodes/1`
* `partisan:monitor_nodes/2`
## OTP compatibility
#### Fixes
#### Changes
* Partisan now requires **OTP24 or later**.
* Upgraded `partisan_gen` and `partisan_gen_server` to match their OTP24 counterparts implementation
* Added `partisan_gen_statem`
* `partisan_gen_fsm` deprecated as it was not complete and focus was given to the implementation of `partisan_gen_statem` instead
* Module `partisan_mochiglobal` has been removed and replaced by `persistent_term`
## Misc
#### Fixes
* Most existing `INFO` level logs have been reclassified as `DEBUG`
* Fixed types specifications in various modules
#### Changes
* `lager` dependency has been removed and all logging is done using the new Erlang `logger`
* Most uses of the `orddict` module have been replaced by maps for extra performance and better usability
* Most API options using `proplists` module have been replaced by maps for extra performance and better usability
* In several functions the computation of options (merging user provided with defaults, validation, etc.) has been postponed until (and only if) it is needed for extra performance e.g. `partisan_pluggable_peer_servie_manager:forward_message`
* More utils in `partisan_util`
* Added `ex_doc` (Elixir documentation) rebar plugin
* Upgraded the following dependencies:
* `uuid`
* `types`
* rebar plugins
