Rig up chat to be suitable for a Doge election. (Hopefully.) (#692)

* Integrate chat from upstream

Substantially borrowed from upstream ref: 13a208ee88e55 (before they
started editing generated artefacts instead of source).

Integrated, including:
  - Remove previously removed features: emoji, hats, and name colors
  - Compensate for lack of unified root template
  - Add React build process to Dockerfile and `bootstrap/init.sh`
  - Preliminary integration of chat websocket workers

For testing, modify `supervisord.conf.dev` to put chat on port 80 and
the site service on some other port. Then visit: http://localhost/chat

Still to do:
  - Access control for specific small-groups (and admins probably):
    Set the values somewhere (site_settings.json? Redis?) and use for
    authorization in `chat_is_allowed`.
  - Proxying only /chat to the websocket workers
  - Chat persistance across restarts: either Redis devops or to DB

* Add nginx server to do appropriate redirection.

* Add necessary columns to User.

* Wire up chat permissions.

* Reload chat on source change.

* Add a better structure for slash commands and add/remove functionality.

* Stop putting up previews of slash commands.

* We require more whitespace.

* Strip DMs out entirely, I currently do not want to deal with them.

* Change "Users Online" to just "Users".

* Clean up a little more DM detritus.

* Save chat history in database.

* Remove unnecessary hefty query to the DB.

* Clean up optimistic messages.

* Initial implementation of notification icon.

* Update readme a little bit.

* Fix notification highlight (mostly).

* Remove chat version number that will never be updated.

* Fix: Errors on logged-out users.

* Add function to nuke the chat state.

* Update DB.

* Add a dedicated deployable docker image.

* Fix: init_build.sh execute bit not set.

* Whoops, screwed up the abort() call.

* Relax chat rate limiter.

* Remove a somewhat silly comment.

* Remove an unnecessary g.db.add().

---------

Co-authored-by: TLSM <duolsm@outlook.com>

Dockerfile

@@ -23,8 +23,23 @@ CMD [ "bootstrap/init.sh" ]
 
 
 ###################################################################
-# Release container
-FROM base AS release
+# Environment capable of building React files
+FROM base AS build
+
+# Chat compilation framework
+ENV NODE_VERSION=16.13.0
+RUN curl -o- https://raw.githubusercontent.com/nvm-sh/nvm/v0.39.0/install.sh | bash
+ENV NVM_DIRECTORY=/root/.nvm
+RUN . "$NVM_DIRECTORY/nvm.sh" && nvm install ${NODE_VERSION}
+RUN . "$NVM_DIRECTORY/nvm.sh" && nvm use v${NODE_VERSION}
+RUN . "$NVM_DIRECTORY/nvm.sh" && nvm alias default v${NODE_VERSION}
+ENV PATH="/root/.nvm/versions/node/v${NODE_VERSION}/bin/:${PATH}"
+RUN npm i -g yarn
+
+
+###################################################################
+# Release-mimicking environment
+FROM build AS release
 
 RUN poetry install --without dev
 
@@ -32,8 +47,8 @@ COPY bootstrap/supervisord.conf.release /etc/supervisord.conf
 
 
 ###################################################################
-# Dev container
-FROM release AS dev
+# Dev environment
+FROM build AS dev
 
 RUN poetry install --with dev
 
@@ -53,3 +68,29 @@ CMD sleep infinity
 
 # Turn off the rate limiter
 ENV DBG_LIMITER_DISABLED=true
+
+
+###################################################################
+# Deployable standalone image
+
+# First, use the `build` container to actually build stuff
+FROM build AS build_built
+COPY . /service
+RUN bootstrap/init_build.sh
+
+# Now assemble our final container
+# Gotta start from base again so we don't pick up the Node framework
+FROM base AS deploy
+
+RUN poetry install --without dev
+COPY bootstrap/supervisord.conf.release /etc/supervisord.conf
+
+# All the base files
+COPY . /service
+
+# Our built React files
+COPY --from=build_built /service/files/assets/css/chat_done.css files/assets/css/chat_done.css
+COPY --from=build_built /service/files/assets/js/chat_done.js files/assets/js/chat_done.js
+
+# Flag telling us not to try rebuilding React
+RUN touch prebuilt.flag