override fun populateInstances()

in aws-ecs-server/src/main/kotlin/jetbrains/buildServer/clouds/ecs/EcsCloudImageImpl.kt [173:227]
52 lines of code
9 McCabe index (conditional complexity)

    override fun populateInstances() {
        LOG.debug("Populating instances for $name")
        try {
            val startedBy = startedByTeamCity(serverUUID)

            val runningTasks = apiConnector.listRunningTasks(cluster, startedBy).mapNotNull { taskArn -> apiConnector.describeTask(taskArn, cluster) }
            val stoppedTasks = apiConnector.listStoppedTasks(cluster, startedBy).mapNotNull { taskArn -> apiConnector.describeTask(taskArn, cluster) }
            LOG.debug("Will process ${runningTasks.size} running and ${stoppedTasks.size} stopped tasks")

            synchronized(myIdToInstanceMap) {
                val keySet = HashSet(myIdToInstanceMap.keys)
                val newTasks = ArrayList<EcsTask>()
                for (task in runningTasks.union(stoppedTasks)) {
                    val taskProfileId = task.getOverridenContainerEnv(PROFILE_ID_ECS_ENV)
                    val taskImageId = task.getOverridenContainerEnv(IMAGE_ID_ECS_ENV)
                    if(profileId == taskProfileId && taskImageId == id){
                        val instanceId = task.getOverridenContainerEnv(INSTANCE_ID_ECS_ENV)
                        if(instanceId == null) {
                            LOG.warn("Can't resolve cloud instance id of ecs task ${task.arn}")
                            continue
                        }
                        if (keySet.remove(instanceId)) {
                            val instance = myIdToInstanceMap[instanceId]
                            if (instance == null) {
                                LOG.warn("Unable to find instance with id '$instanceId'. Was it removed?")
                                continue
                            }
                            instance.update(task)
                        } else {
                            newTasks.add(task)
                        }
                    }
                }
                //remove absent instances
                keySet.forEach {
                    LOG.info("Instance '$it' is no longer available")
                    myIdToInstanceMap.remove(it)
                }
                newTasks.forEach{
                    val instanceId = it.getOverridenContainerEnv(INSTANCE_ID_ECS_ENV)
                    if (instanceId != null) {
                        LOG.info("Found new instance '$instanceId'")
                        myIdToInstanceMap[instanceId] = EcsCloudInstanceImpl(instanceId, this, it, apiConnector)
                    } else {
                        LOG.info("Found no instance id for task with arn '${it.arn}'")
                    }
                }
                myCurrentError = null
            }
        } catch (ex: Throwable) {
            val msg = "Unable to populate instances for ${imageData.id}"
            LOG.warnAndDebugDetails(msg, ex)
            myCurrentError = CloudErrorInfo(msg, ex.message.toString(), ex)
        }
    }