YAS

Yet Another Slack bot

The operations team at Refinery29 was replacing a old system for launching development systems which utilized an older version of Hubot. At the time our team was more comfortable with python than the Node/Coffeescript which Hubot is built on, and we were already familiar with python modules with which we could interface with the systems we wanted our new bot to interact with. Thus YAS was born.

YAS is framework which tests Slack messages which are available to it against handlers which will operate on a message if they are the first handler to produce a truthy result upon running a test against the message. A simple practical example is the built in id handler. This handler has a test which looks for a message starting with id. If it does, the handler is invoked, replying with some information about the server yas is running on.

Slack has a number of message types of which only a few are initiated by a user and in most cases only a subset of user initiated messages will be meant to be handled by your bot. To handle these cases a number of handlers are included with yas, but are not automatically added, and must be included in the list of handlers when that is configured.

Setup

Yas may be run directly, but it won't do much, so setup including one or more additional handlers will be included here.

The easiest method (as of version 2.0) is to construct a Docker image based on the yas image and install the additional handlers and configure them. Alternatively, if any of the handlers has a Dockerfile available, that could be used as a base on which to add any others, but since Docker files need to be manually combined it is likely easier to simply construct a new image based directly on yas'. For instance, the yas-jenkins handler can be built with a Dockerfile such as:

FROM schlueter/yas:latest

ENV YAS_JENKINS_JOBS '{}'
ENV YAS_JENKINS_URL ''
ENV YAS_JENKINS_USERNAME ''
ENV YAS_JENKINS_PASSWORD ''

COPY . .
RUN python -m pip install yas-jenkins

To add an additional handler, its configuration need only be added and it installed as well.

Once built, the resulting image may be run with the appropriate configuration provided in environment variables with:

docker run --rm --tty \
 --env YAS_SLACK_TOKEN=xoxb-XXXXXXXXXXXX-XXXXXXXXXXXXXXXXXXXXXXXX \
 --env YAS_BOT_NAME=yas \
 --env YAS_JENKINS_URL=https://jenkins.example.com \
 --env YAS_JENKINS_USERNAME=yas \
 --env YAS_JENKINS_PASSWORD=supersecret \
 --env YAS_JENKINS_JOBS='{"MyJob": "build (?P<branch>\\w+)"}' \
 --env YAS_HANDLER_LIST=yas.handlers.ignored_types_handler.,yas.handlers.not_talking_to_bot_handler.,yas.handlers.help_handler.,yas.handlers.identify_handler.,YasJenkinsHandler.,yas.handlers.rules_handler.,yas.handlers.default_handler. \
 my-yas-image:my-tag

For yas to function, the YAS_SLACK_TOKEN, YAS_BOT_NAME, and YAS_HANDLER_LIST variables must be provided. The token and name must be obtained/configured from a new or existing bot in your Slack organization. A new bot may be created at https://my.slack.com/services/new/bot.

The handler list should include most of the default handlers, potentially discluding those not being generally necessary to yas' normal functioning being the identify_handler, rules_handler, and the default_handler. The help_handler is also not necessary to yas operating in a reasonable manner, but it may be utilized by other plugins to make help functionality available.