org.apache.james.mailbox.cassandra.mail.AttachmentLoader.java Source code

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Here is the source code for org.apache.james.mailbox.cassandra.mail.AttachmentLoader.java

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package org.apache.james.mailbox.cassandra.mail;

import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.concurrent.CompletableFuture;
import java.util.function.Function;
import java.util.stream.Stream;

import org.apache.commons.lang3.tuple.Pair;
import org.apache.james.mailbox.model.Attachment;
import org.apache.james.mailbox.model.AttachmentId;
import org.apache.james.mailbox.model.MessageAttachment;
import org.apache.james.mailbox.store.mail.MessageMapper;
import org.apache.james.mailbox.store.mail.model.impl.SimpleMailboxMessage;
import org.apache.james.util.FluentFutureStream;

import com.github.steveash.guavate.Guavate;
import com.google.common.annotations.VisibleForTesting;
import com.google.common.collect.ImmutableList;
import com.google.common.collect.ImmutableMap;

public class AttachmentLoader {

    private final CassandraAttachmentMapper attachmentMapper;

    public AttachmentLoader(CassandraAttachmentMapper attachmentMapper) {
        this.attachmentMapper = attachmentMapper;
    }

    public CompletableFuture<Stream<SimpleMailboxMessage>> addAttachmentToMessages(
            Stream<Pair<MessageWithoutAttachment, Stream<MessageAttachmentRepresentation>>> messageRepresentations,
            MessageMapper.FetchType fetchType) {

        if (fetchType == MessageMapper.FetchType.Body || fetchType == MessageMapper.FetchType.Full) {
            return FluentFutureStream
                    .<SimpleMailboxMessage>of(messageRepresentations
                            .map(pair -> getAttachments(pair.getRight().collect(Guavate.toImmutableList()))
                                    .thenApply(attachments -> pair.getLeft().toMailboxMessage(attachments))))
                    .completableFuture();
        } else {
            return CompletableFuture.completedFuture(
                    messageRepresentations.map(pair -> pair.getLeft().toMailboxMessage(ImmutableList.of())));
        }
    }

    @VisibleForTesting
    CompletableFuture<List<MessageAttachment>> getAttachments(
            List<MessageAttachmentRepresentation> attachmentRepresentations) {
        CompletableFuture<Map<AttachmentId, Attachment>> attachmentsByIdFuture = attachmentsById(
                attachmentRepresentations.stream().map(MessageAttachmentRepresentation::getAttachmentId)
                        .collect(Guavate.toImmutableSet()));

        return attachmentsByIdFuture.thenApply(attachmentsById -> attachmentRepresentations.stream()
                .map(representation -> constructMessageAttachment(
                        attachmentsById.get(representation.getAttachmentId()), representation))
                .collect(Guavate.toImmutableList()));
    }

    private MessageAttachment constructMessageAttachment(Attachment attachment,
            MessageAttachmentRepresentation messageAttachmentRepresentation) {
        return MessageAttachment.builder().attachment(attachment)
                .name(messageAttachmentRepresentation.getName().orElse(null))
                .cid(messageAttachmentRepresentation.getCid()).isInline(messageAttachmentRepresentation.isInline())
                .build();
    }

    @VisibleForTesting
    CompletableFuture<Map<AttachmentId, Attachment>> attachmentsById(Set<AttachmentId> attachmentIds) {
        if (attachmentIds.isEmpty()) {
            return CompletableFuture.completedFuture(ImmutableMap.of());
        }
        return attachmentMapper.getAttachmentsAsFuture(attachmentIds).thenApply(attachments -> attachments.stream()
                .collect(Guavate.toImmutableMap(Attachment::getAttachmentId, Function.identity())));
    }

}