Examples with ApplicationFilter io.cdap.cdap.app.store.ApplicationFilter used on opensource projects

Example 1 with ApplicationFilter

use of io.cdap.cdap.app.store.ApplicationFilter in project cdap by caskdata.

the class AppMetadataStore method scanApplications.

/**
 * Scans applications. Allows to optionally set namespace / filters and implement pagination. For pagination
 * set {@link ScanApplicationsRequest#getScanFrom()} to the last application id of the previous page.
 *
 * @param request parameters defining filters and sorting
 * @param func a {@link Function} to consume application metadata entries generated by the scan. The boolean
 *             value returned is {@code true}, the scan will continue; otherwise the scan will stop and return.
 *             Note that the parameter is a {@link Map.Entry} to allow lazy deserialization of
 *             {@link ApplicationMeta} and it should not be replaced with {@link BiFunction}.
 * @see ScanApplicationsRequest#builder(ScanApplicationsRequest) to create a next page / batch request
 * @throws IOException if failed to scan the storage
 */
public void scanApplications(ScanApplicationsRequest request, Function<Map.Entry<ApplicationId, ApplicationMeta>, Boolean> func) throws IOException {
    Range.Bound startBound = Range.Bound.INCLUSIVE;
    Collection<Field<?>> startFields = request.getNamespaceId() == null ? Collections.emptyList() : Collections.singletonList(Fields.stringField(StoreDefinition.AppMetadataStore.NAMESPACE_FIELD, request.getNamespaceId().getNamespace()));
    Range.Bound endBound = Range.Bound.INCLUSIVE;
    Collection<Field<?>> endFields = startFields;
    if (request.getScanFrom() != null) {
        if (request.getNamespaceId() != null && !request.getNamespaceId().equals(request.getScanFrom().getNamespaceId())) {
            throw new IllegalArgumentException("Requested to start scan from application " + request.getScanFrom() + " that is outside of scan namespace " + request.getNamespaceId());
        }
        startBound = Range.Bound.EXCLUSIVE;
        startFields = getApplicationPrimaryKeys(request.getScanFrom());
    }
    if (request.getScanTo() != null) {
        if (request.getNamespaceId() != null && !request.getNamespaceId().equals(request.getScanTo().getNamespaceId())) {
            throw new IllegalArgumentException("Requested to finish scan at application " + request.getScanTo() + " that is outside of scan namespace " + request.getNamespaceId());
        }
        endBound = Range.Bound.EXCLUSIVE;
        endFields = getApplicationPrimaryKeys(request.getScanTo());
    }
    Range range;
    if (request.getSortOrder() == SortOrder.ASC) {
        range = Range.create(startFields, startBound, endFields, endBound);
    } else {
        range = Range.create(endFields, endBound, startFields, startBound);
    }
    // As of now this is where we push filter to. it does not go to the StructuredTable,
    // but we don't deserialize ApplicationMeta unless needed
    Predicate<AppScanEntry> scanEntryPredicate = e -> true;
    for (ApplicationFilter filter : request.getFilters()) {
        if (filter instanceof ApplicationFilter.ApplicationIdFilter) {
            scanEntryPredicate = scanEntryPredicate.and(e -> ((ApplicationFilter.ApplicationIdFilter) filter).test(e.getKey()));
        } else if (filter instanceof ApplicationFilter.ArtifactIdFilter) {
            scanEntryPredicate = scanEntryPredicate.and(e -> ((ApplicationFilter.ArtifactIdFilter) filter).test(e.getValue().getSpec().getArtifactId()));
        } else {
            throw new UnsupportedOperationException("Application filter " + filter + " is not supported");
        }
    }
    StructuredTable table = getApplicationSpecificationTable();
    int limit = request.getLimit();
    try (CloseableIterator<StructuredRow> iterator = table.scan(range, Integer.MAX_VALUE, request.getSortOrder())) {
        boolean keepScanning = true;
        while (iterator.hasNext() && keepScanning && limit > 0) {
            StructuredRow row = iterator.next();
            AppScanEntry scanEntry = new AppScanEntry(row);
            if (scanEntryPredicate.test(scanEntry)) {
                keepScanning = func.apply(scanEntry);
                limit--;
            }
        }
    }
}