Format arguments to have nested structures start on a new line instead
of inline to make it easier to see where the structures starts and what
structure it is.
Split up the action of registring an event or request data class to be
decoded by the Link class and the action of registring a handler for
those requests and events. This moves the validation work from Link
instantiation time to startup initialisation which makes logic errors
fail on startup instead of failing instantiation of the link when a
connection attempt is made.
Additionally implement a partial validation logic for messages received
using the newly refactored message registration. This unfortunately
ended up merged with the registration refactor.
Reverse the direction of the API for sending messages from
messageDefinition.send(link, { content });
to
link.send(new MessageClass(content));
and convert all message definitions to use the JSON serialisable class
pattern and explicit registration of message handlers, along with a
end-to-end based routing of messages instead of link to link.
The experience I gained from the existing way messages were defined and
sent over links was that it was difficult to understand for people
unfamiliar with the system. The automatic registration of message
handlers ment that code was being called as if by magic from nowhere
with no easy way to discover it. The manual forwarding and rules for
what can be sent where and how obscured its working.
The use of pure JSON as both input and output from message handlers made
it tedious to work with. Data had to be manually converted between the
program representation and the over the wire format, which made handler
code unplesant to write. Particularly because the over the wire format
used snake_case while the program code uses camelCase for variables.
The idea behind the decision to do it this way was to make it more clear
which data came from the wire and which from the program, and while this
worked it didn't make message handlers any nicer to write.
The direction of the API and magic registration of message handlers also
meant that a future migration to TypeScript would be troublesome. While
it may be possible to implement, the degree of TypeScript magic required
would go starkly against the principle of keep it simple stupid.
By refactoring to using the JSON serialisable class pattern most of
these issues go away. There is no longer a need to distinguish the on
wire format of messages with the program representation because the only
place that deals with the wire format of messages are the toJSON and
fromJSON methods on the classes themselves. Message handlers will work
with proper instances of classes instead of raw data, something that
makes them easier to write, and trivial to type with TypeScript.
End-to-end routing also simplifies sending messages that need to do
mulitple hops to reach the destination. And removes the need for having
all messages be specified in plugin's info module, as they can be routed
without having to be parsed completely.
The explicit registration of message handlers is something that I
thought would be tedious boilerplate code that could be automated away.
But experience now shows it to be the opposite. Allthough dull
repetition, the purpose it serves is to link together the code in a way
that humans can easily find. With explicit registration searching the
name of the message handler in the editor will show the registration that
ties it together with the type of message it handles and the kind of
registration. With implicit registration searching the name of the
message handler turns up only the handler with no clue as to what calls
it.
Change the JSON seriasiable data classes to use an explicit static
fromJSON method and an optional toJSON method for turning them to and
from JSON.
This improves over the previous pattern of passing the JSON to the
constructor as it frees up the constructor to be able to take whichever
argument types suits the code instead of being beholden to the JSON
serialised form.
The role of a slave as a host for Factorio servers is not well reflected
in its name and has caused confusion among users. Rename slave to host
to better reflect its role as a host of Factorio servers.
The role of the master server as the party controlling every part of the
cluster is not well reflected in its name and has caused confusion among
users on several occasions. Rename master to controller to better
reflects its role.
Add ModPack data type with corresponding storage on the master, messages
to create, update and delete them, as well as commands to invoke them.
The ModPack data type contains a list of mods with versions and optional
sha1 hashes, and mod settings to be used.
Add the ability to manage a set of mods to be shared by the master
server to the rest of the cluster. This implements storage, uploads,
downloads, deletetion, and listing details of mods but does not actually
do anything with the stored mods.
Add the roles and their permissions for the user the control connection
is connected as along with updates when these change. This enables the
web interface to know which permissions it has available to it.
Refine the state flow used in the connector abstractions to better
handle close while connecting and resuming. The new logic is to close
the connection immediately in these two states instead of continuing
trying to connect and then giving up some point later.
For the connectors the handshake state is split into connecting
and resuming, new is replaced by closed, and the closing state is turned
into a boolean flag as it's possible that closing is desired while
connecting, connected or resuming. The connecting state is not present
in the server connector because there's nothing for the server to do in
that connector state.
The timeout logic is completely removed, once a connection attempt is
started for the client it will continue to attempt to connect, attempt
to resume dropped connections and attempt reconnects until either an
authentication error occurs or the client explicitly requests to close
the connection.
A new session timeout is added to control how long to attempt to resume
the connection until it's considered dead and invalidated. This allows
stale connections to give up earlier, and swallow up less data while in
the dropped but not yet invalidated state.
For the client side sending messages while it's connecting has been
changed to throw an error instead of queuing up the message and
(possibly) sending it after the connection is established. Code
shouldn't try to send messages without knowing if the connection it's
trying to send them over is active or not.
In order to import a path inside packages/lib/ in the webpack shared
module environment it has to be declared as shared in both the web_ui
webpack config and the plugin's webpack config. This is rather error
prone and easy to miss. Move the burden of specifying which entrypoints
are valid in lib to lib itself by changing all imports in the web
interface code to import from @clusterio/lib instead sub paths.
For web code this means imports is done like this from now on:
import { libConfig, libLink } from "@clusterio/lib";
For info.js which has to be loadable by both Node.js and web code the
imports are done as follows:
const { libConfig, libLink } = require("@clusterio/lib");
While the Node.js only code can either continue to import sub paths
directly or use the info.js style.
Add link messages for listing saves and listening for changes to the
list of saves for instances along with a table in the instance view page
showing the save list for the instance and a list-saves command to ctl.
Provide the control link with the ability to subscribe to updates when
instance status and properties changes. This allows the web interface
to respond in real time to instance starts and stops that are triggered
from somewhere else.
Add reference to the Control instance in BaseWebPlugin for web plugin
code to use in a similar manner to the instance reference in instance
plugin code.
Add the name of the account that's connected to the control link on the
web interface via an additional property on the ready payload for the
control link.
Add a button on the right of the top nav bar to access account related
functions and add a log out button there. To make it fit on the navbar
the text and version is hidden on narrow layouts.
Add separate BaseWebPlugin class which plugins can extend and expose
through a webEntrypoint in a similar fasion to the existing master,
instance and control entrypoints.
To simplify the logic for the rest of the web interface code the plugins
context is changed to be a mapping of loaded WebPlugin instances. This
in turn means the plugins and plugin view pages fetches the plugin list
upon load in order to show plugins that failed to load (which
incidentally also gives them an up to date list).
Add log query and log follow commands which allows inspection of the
combined cluster log. Past entries can be queried via the new queryLog
request. The log is stored into a single flat file for now, though the
performance of this may good enough.
Add winston based logger for master, slave, ctl, lib, and web_ui code.
Logging done from slaves and instances are sent to the master server and
tagged with the instance and/or slave it originated from. This allows
for example error messages to propagate back to the source that iniated
the action. The master server also stores the log to allow it to be
queried at a later point. For slaves a copy of the slave's log is also
stored locally.
Fix the console view of the instance web interface losing the output
subscription after a reconnect to the master server due to not
re-subscribing to the outputs.