Unable to start BuildBot Master from Docker Image

Unable to start BuildBot Master from Docker Image. I use the following configuration.

services:
db:
image: postgres:16.4-bookworm
environment:
  POSTGRES_PASSWORD: change_me
  POSTGRES_USER: buildbot
  POSTGRES_DB: buildbot
buildbot:
image: buildbot/buildbot-master:v4.0.2
depends_on:
  - db
environment:
  BUILDBOT_CONFIG_DIR: config
  BUILDBOT_CONFIG_URL: https://github.com/buildbot/buildbot-docker-example-config/archive/master.tar.gz
  BUILDBOT_WORKER_PORT: 9989
  BUILDBOT_WEB_URL: http://localhost:8010/
  BUILDBOT_WEB_PORT: tcp:port=8010
  BUILDBOT_DB_URL: postgresql+psycopg2://buildbot:change_me@db/buildbot
ports:
  - "8010:8010"
worker:
image: buildbot/buildbot-worker:v4.0.2
environment:
  BUILDMASTER: buildbot
  BUILDMASTER_PORT: 9989
  WORKERNAME: example-worker
  WORKERPASS: pass
  WORKER_ENVIRONMENT_BLACKLIST: DOCKER_BUILDBOT* BUILDBOT_ENV_* BUILDBOT_1* WORKER_ENVIRONMENT_BLACKLIST

After executing docker compose up -d, I get the following Error Log.

master_cfg = base.loadConfig(config, configFile)
File "/buildbot_venv/lib/python3.9/site-packages/buildbot/scripts/base.py", line 111, in loadConfig
master_cfg = FileLoader(config['basedir'], configFileName).loadConfig()
File "/buildbot_venv/lib/python3.9/site-packages/buildbot/config/master.py", line 123, in loadConfig
filename, config_dict = loadConfigDict(self.basedir, self.configFileName)
--- <exception caught here> ---
File "/buildbot_venv/lib/python3.9/site-packages/buildbot/config/master.py", line 85, in loadConfigDict
execfile(filename, localDict)
File "/buildbot_venv/lib/python3.9/site-packages/twisted/python/compat.py", line 214, in execfile
exec(code, globals, locals)
File "/buildbot/master.cfg", line 45, in <module>
c['change_source'].append(changes.GitPoller(
File "/buildbot_venv/lib/python3.9/site-packages/buildbot/changes/gitpoller.py", line 75, in __init__
super().__init__(repourl, **kwargs)
File "/buildbot_venv/lib/python3.9/site-packages/buildbot/util/service.py", line 294, in __init__
super().__init__(*args, **kwargs)
File "/buildbot_venv/lib/python3.9/site-packages/buildbot/util/service.py", line 189, in __init__
self.checkConfig(*args, **kwargs)
builtins.TypeError: checkConfig() got an unexpected keyword argument 'pollinterval'

Am I missing something in the documentation?

@ThomasDevoogdt

Thanks for the clarification, I realized that the documentation mentioned https://github.com/buildbot/buildbot-docker-example-config/archive/master.tar.gz which is actually outdated.
I noticed that https://docs.buildbot.net/4.0.2/tutorial/firstrun.html suggests manually creating a new file named master.cfg from master.cfg.sample.

Buildbot’s activity is controlled by a configuration file. Buildbot by default uses configuration from file at master.cfg, but its installation comes with a sample configuration file named master.cfg.sample. We will use the sample configuration file unchanged, but we have to rename it to master.cfg

And in https://github.com/buildbot/buildbot/blob/v4.0.2/master/buildbot/scripts/create_master.py#L62 , master.cfg.sample is renamed from sample.cfg. sample.cfg is actually https://github.com/buildbot/buildbot/blob/v4.0.2/master/buildbot/scripts/sample.cfg .

def makeSampleConfig(config):
source = util.sibpath(__file__, "sample.cfg")
target = os.path.join(config['basedir'], "master.cfg.sample")
if not config['quiet']:
    print(f"creating {target}")
with open(source, "rt", encoding='utf-8') as f:
    config_sample = f.read()
if config['db']:
    config_sample = config_sample.replace('sqlite:///state.sqlite', config['db'])
with open(target, "wt", encoding='utf-8') as f:
    f.write(config_sample)
os.chmod(target, 0o600)

This file needs to be placed in /buildbot/master.cfg as required by https://github.com/buildbot/buildbot/blob/v4.0.2/master/docker/start_buildbot.sh.
```
B=$(pwd)
```

if [ -z "$BUILDBOT_CONFIG_URL" ] then if [ ! -f "$B/master.cfg" ] then echo "No master.cfg found nor \$BUILDBOT_CONFIG_URL!" echo "Please provide a master.cfg file in $B or provide a \$BUILDBOT_CONFIG_URL variable via -e"


- So I changed the `docker-compose.yml` file.
```yaml
services:
  db:
    image: postgres:16.4-bookworm
    environment:
      POSTGRES_PASSWORD: change_me
      POSTGRES_USER: buildbot
      POSTGRES_DB: buildbot
  buildbot:
    image: buildbot/buildbot-master:v4.0.2
    depends_on:
      - db
    environment:
      BUILDBOT_CONFIG_DIR: config
      BUILDBOT_WORKER_PORT: 9989
      BUILDBOT_WEB_URL: http://localhost:8010/
      BUILDBOT_WEB_PORT: tcp:port=8010
      BUILDBOT_DB_URL: postgresql+psycopg2://buildbot:change_me@db/buildbot
    ports:
      - "8010:8010"
    volumes:
      - ./buildbot-master/master.cfg:/buildbot/master.cfg
  worker:
    image: buildbot/buildbot-worker:v4.0.2
    environment:
      BUILDMASTER: buildbot
      BUILDMASTER_PORT: 9989
      WORKERNAME: example-worker
      WORKERPASS: pass
      WORKER_ENVIRONMENT_BLACKLIST: DOCKER_BUILDBOT* BUILDBOT_ENV_* BUILDBOT_1* WORKER_ENVIRONMENT_BLACKLIST

The file content of ./buildbot-master/master.cfg is as follows.

from buildbot.plugins import *
c = BuildmasterConfig = {}
c['workers'] = [worker.Worker("example-worker", "pass")]
c['protocols'] = {'pb': {'port': 9989}}
c['change_source'] = []
c['change_source'].append(changes.GitPoller(
    'https://github.com/buildbot/hello-world.git',
    workdir='gitpoller-workdir', branch='master',
    pollInterval=300))
c['schedulers'] = []
c['schedulers'].append(schedulers.SingleBranchScheduler(
                        name="all",
                        change_filter=util.ChangeFilter(branch='master'),
                        treeStableTimer=None,
                        builderNames=["runtests"]))
c['schedulers'].append(schedulers.ForceScheduler(
                        name="force",
                        builderNames=["runtests"]))
factory = util.BuildFactory()
factory.addStep(steps.Git(repourl='https://github.com/buildbot/hello-world.git', mode='incremental'))
factory.addStep(steps.ShellCommand(command=["trial", "hello"],
                               env={"PYTHONPATH": "."}))
c['builders'] = []
c['builders'].append(
util.BuilderConfig(name="runtests",
  workernames=["example-worker"],
  factory=factory))
c['services'] = []
c['title'] = "Hello World CI"
c['titleURL'] = "https://buildbot.github.io/hello-world/"
c['buildbotURL'] = "http://localhost:8010/"
c['www'] = dict(port=8010,
            plugins=dict(waterfall_view={}, console_view={}, grid_view={}))
c['db'] = {
'db_url' : "sqlite:///state.sqlite",
}

I can now access http://localhost:8010/ just fine.
It would be nice if https://docs.buildbot.net/4.0.2/tutorial/docker.html gave an example of a master.cfg. This is a bit unintuitive.

buildbot / buildbot

Unable to start BuildBot Master from Docker Image #7946