function _M:start_worker()

in kong/spec/helpers/perf/drivers/docker.lua [202:279]

• 66 lines of code
• 10 McCabe index (conditional complexity)

function _M:start_worker(conf, port_count)
  conf = conf or [[
    location = /test {
      return 200;
    }
  ]]

  local listeners = {}
  for i=1,port_count do
    listeners[i] = ("listen %d reuseport;"):format(UPSTREAM_PORT+i-1)
  end
  listeners = table.concat(listeners, "\n")

  if not self.worker_ct_id then
    local _, err = perf.execute(
      "docker build --progress plain -t perf-test-upstream -",
      {
        logger = self.log.log_exec,
        stdin = ([[
        FROM nginx:alpine
        RUN apk update && apk add wrk
        RUN echo -e '\
        server {\
          %s\
          access_log off;\
          location =/health { \
            return 200; \
          } \
          %s \
        }' > /etc/nginx/conf.d/perf-test.conf

        # copy paste
        ENTRYPOINT ["/docker-entrypoint.sh"]

        STOPSIGNAL SIGQUIT

        CMD ["nginx", "-g", "daemon off;"]
      ]]):format(listeners:gsub("\n", "\\n"), conf:gsub("\n", "\\n"))
      }
    )
    if err then
      return false, err
    end

    local cid, err = create_container(self, "-p " .. UPSTREAM_PORT, "perf-test-upstream")
    if err then
      return false, "error running docker create when creating upstream: " .. err
    end
    self.worker_ct_id = cid
  end

  self.log.info("worker container ID is ", self.worker_ct_id)

  local ok, err = start_container(self.worker_ct_id)
  if not ok then
    return false, "worker is not running: " .. err
  end
  ngx.sleep(3) 

  local worker_vip, err = get_container_vip(self.worker_ct_id)
  if err then
    return false, "unable to read worker container's private IP: " .. err
  end

  if not perf.wait_output("docker logs -f " .. self.worker_ct_id, " start worker process") then
    self.log.info("worker container logs:")
    perf.execute("docker logs " .. self.worker_ct_id, { logger = self.log.log_exec })
    return false, "timeout waiting worker(nginx) to start (5s)"
  end

  self.log.info("worker is started")

  local uris = {}
  for i=1,port_count do
    uris[i] = "http://" .. worker_vip .. ":" .. UPSTREAM_PORT+i-1
  end
  return uris
end