private void resolveCommand()

in genie-web/src/main/java/com/netflix/genie/web/services/impl/JobResolverServiceImpl.java [346:445]
78 lines of code
6 McCabe index (conditional complexity)

    private void resolveCommand(final JobResolutionContext context) throws GenieJobResolutionException {
        final long start = System.nanoTime();
        final Set<Tag> tags = new HashSet<>();
        try {
            final JobRequest jobRequest = context.getJobRequest();
            final Criterion criterion = jobRequest.getCriteria().getCommandCriterion();

            //region Algorithm Step 1
            final Set<Command> commands = this.persistenceService.findCommandsMatchingCriterion(criterion, true);

            // Short circuit if there are no commands
            if (commands.isEmpty()) {
                throw new GenieJobResolutionException("No command matching command criterion found");
            }
            //endregion

            //region Algorithm Step 2
            final Map<Command, List<Criterion>> commandClusterCriterions = this.generateClusterCriteriaPermutations(
                commands,
                jobRequest
            );

            final Set<Criterion> uniqueCriteria = this.flattenClusterCriteriaPermutations(commandClusterCriterions);

            final Set<Cluster> allCandidateClusters = this.persistenceService.findClustersMatchingAnyCriterion(
                uniqueCriteria,
                true
            );
            if (allCandidateClusters.isEmpty()) {
                throw new GenieJobResolutionException("No clusters available to run any candidate command on");
            }
            //endregion

            //region Algorithm Step 3
            final Map<Command, Set<Cluster>> commandClusters = this.generateCommandClustersMap(
                commandClusterCriterions,
                allCandidateClusters
            );
            // this should never really happen based on above check but just in case
            if (commandClusters.isEmpty()) {
                throw new GenieJobResolutionException("No clusters available to run any candidate command on");
            }
            // save the map for use later by cluster resolution
            context.setCommandClusters(commandClusters);
            //endregion

            //region Algorithm Step 4
            final ResourceSelectionResult<Command> result = this.commandSelector.select(
                new CommandSelectionContext(
                    context.getJobId(),
                    jobRequest,
                    context.isApiJob(),
                    commandClusters
                )
            );
            //endregion

            final Command command = result
                .getSelectedResource()
                .orElseThrow(
                    () -> new GenieJobResolutionException(
                        "Expected a command but "
                            + result.getSelectorClass().getSimpleName()
                            + " didn't select anything. Rationale: "
                            + result.getSelectionRationale().orElse(NO_RATIONALE)
                    )
                );
            LOG.debug(
                "Selected command {} for criterion {} using {} due to {}",
                command.getId(),
                criterion,
                result.getSelectorClass().getName(),
                result.getSelectionRationale().orElse(NO_RATIONALE)
            );

            MetricsUtils.addSuccessTags(tags);
            final String commandId = command.getId();
            final String commandName = command.getMetadata().getName();
            tags.add(Tag.of(MetricsConstants.TagKeys.COMMAND_ID, commandId));
            tags.add(Tag.of(MetricsConstants.TagKeys.COMMAND_NAME, commandName));
            final SpanCustomizer spanCustomizer = context.getSpanCustomizer();
            this.tagAdapter.tag(spanCustomizer, TracingConstants.JOB_COMMAND_ID_TAG, commandId);
            this.tagAdapter.tag(spanCustomizer, TracingConstants.JOB_COMMAND_NAME_TAG, commandName);
            context.setCommand(command);
        } catch (final GenieJobResolutionException e) {
            // No candidates or selector choose none
            tags.add(NO_COMMAND_RESOLVED_ID);
            tags.add(NO_COMMAND_RESOLVED_NAME);
            MetricsUtils.addFailureTagsWithException(tags, e);
            throw e;
        } catch (final ResourceSelectionException t) {
            // Selector runtime error
            MetricsUtils.addFailureTagsWithException(tags, t);
            throw new GenieJobResolutionRuntimeException(t);
        } finally {
            this.registry
                .timer(RESOLVE_COMMAND_TIMER, tags)
                .record(System.nanoTime() - start, TimeUnit.NANOSECONDS);
        }
    }