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    Changes API: How to Subscribe to Document Changes

    Following methods allow you to subscribe to document changes:

    forDocument

    Single document changes can be observed using forDocument method.

    Syntax

    IChangesObservable<DocumentChange> forDocument(String docId);
    Parameters
    docId String ID of a document for which notifications will be processed.
    Return Value
    IChangesObservable<DocumentChange> Observable that allows to add subscriptions to notifications for given document.

    Example

    CleanCloseable subscription = store.changes()
    .forDocument("employees/1")
    .subscribe(Observers.create(change -> {
        switch (change.getType()) {
            case PUT:
                // do something
                break;
            case DELETE:
                // do something
                break;
        }
    }));

    forDocumentsInCollection

    To observe all document changes in particular collection use forDocumentInCollection method. This method filters documents by @collection metadata property value.

    Syntax

    IChangesObservable<DocumentChange> forDocumentsInCollection(String collectionName);

IChangesObservable<DocumentChange> forDocumentsInCollection(Class<?> clazz);
    Parameters
    collectionName String Name of document collection for which notifications will be processed.
    Return Value
    IChangesObservable<DocumentChange> Observable that allows to add subscriptions to notifications for given document collection name.

    Information

    Overload with TEntity type uses conventions.GetCollectionName to get collection name.

    Example

    CleanCloseable subscription = store
    .changes()
    .forDocumentsInCollection(Employee.class)
    .subscribe(Observers.create(change -> {
        System.out.println(change.getType() + " on document " + change.getId());
    }));

    or

    String collectionName = store.getConventions().getFindCollectionName().apply(Employee.class);
CleanCloseable subscription = store
    .changes()
    .forDocumentsInCollection(collectionName)
    .subscribe(Observers.create(change -> {
        System.out.println(change.getType() + " on document " + change.getId());
    }));

    forDocumentsStartingWith

    To observe all document changes for documents with ID that contains given prefix use forDocumentsStartingWith method.

    Syntax

    IChangesObservable<DocumentChange> forDocumentsStartingWith(String docIdPrefix);
    Parameters
    docIdPrefix String Document ID prefix for which notifications will be processed.
    Return Value
    IChangesObservable<DocumentChange> Observable that allows to add subscriptions to notifications for given document ID prefix.

    Example

    CleanCloseable subscription = store
    .changes()
    .forDocumentsStartingWith("employees/1") // employees/1, employees/10, employees/11, etc.
    .subscribe(Observers.create(change -> {
        System.out.println(change.getType() + " on document " + change.getId());
    }));

    forAllDocuments

    To observe all document changes use forAllDocuments method.

    Syntax

    IChangesObservable<DocumentChange> forAllDocuments();
    Return Value
    IChangesObservable<DocumentChange> Observable that allows to add subscriptions to notifications for all documents.

    Example

    CleanCloseable subscription = store
    .changes()
    .forAllDocuments()
    .subscribe(Observers.create(change -> {
        System.out.println(change.getType() + " on document " + change.getId());
    }));

    DocumentChange

    Name Type Description
    Type DocumentChangeTypes Document change type enum
    Id String Document identifier
    CollectionName String Document's collection name
    TypeName String Type name
    ChangeVector String Document's ChangeVector

    DocumentChangeTypes

    Name
    NONE
    PUT
    DELETE
    BULK_INSERT_STARTED
    BULK_INSERT_ENDED
    BULK_INSERT_ERROR
    DELETE_ON_TOMBSTONE_REPLICATION
    CONFLICT
    COMMON

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    Changes API

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