Examples with Transaction com.google.cloud.firestore.Transaction used on opensource projects

Example 1 with Transaction

use of com.google.cloud.firestore.Transaction in project java-docs-samples by GoogleCloudPlatform.

the class ManageDataSnippets method runSimpleTransaction.

// [END fs_delete_collection]
/**
 * Run a simple transaction to perform a field value increment.
 *
 * @return transaction future
 */
ApiFuture<Void> runSimpleTransaction() throws Exception {
    // [START fs_run_simple_transaction]
    // Initialize doc
    final DocumentReference docRef = db.collection("cities").document("SF");
    City city = new City("SF");
    city.setCountry("USA");
    city.setPopulation(860000L);
    docRef.set(city).get();
    // run an asynchronous transaction
    ApiFuture<Void> transaction = db.runTransaction(new Transaction.Function<Void>() {

        @Override
        public Void updateCallback(Transaction transaction) throws Exception {
            // retrieve document and increment population field
            DocumentSnapshot snapshot = transaction.get(docRef).get();
            long oldPopulation = snapshot.getLong("population");
            transaction.update(docRef, "population", oldPopulation + 1);
            return null;
        }
    });
    // [END fs_run_simple_transaction]
    return transaction;
}

Example 2 with Transaction

use of com.google.cloud.firestore.Transaction in project jade-data-repo by DataBiosphere.

the class FireStoreDirectoryDao method enumerateDirectory.

// -- private methods --
List<FireStoreDirectoryEntry> enumerateDirectory(Firestore firestore, String collectionId, String dirPath) {
    ApiFuture<List<FireStoreDirectoryEntry>> transaction = firestore.runTransaction(xn -> {
        Query query = firestore.collection(collectionId).whereEqualTo("path", dirPath);
        ApiFuture<QuerySnapshot> querySnapshot = xn.get(query);
        List<QueryDocumentSnapshot> documents = querySnapshot.get().getDocuments();
        List<FireStoreDirectoryEntry> entryList = documents.stream().map(document -> document.toObject(FireStoreDirectoryEntry.class)).collect(Collectors.toList());
        return entryList;
    });
    return fireStoreUtils.transactionGet("enumerateDirectory", transaction);
}

Example 3 with Transaction

use of com.google.cloud.firestore.Transaction in project java-docs-samples by GoogleCloudPlatform.

the class ManageDataSnippets method returnInfoFromTransaction.

/**
 * Return information from a conditional transaction.
 *
 * @param population : set initial population.
 */
String returnInfoFromTransaction(long population) throws Exception {
    Map<String, Object> map = new HashMap<>();
    map.put("population", population);
    // Block until transaction is complete is using transaction.get()
    db.collection("cities").document("SF").set(map).get();
    // [START fs_return_info_transaction]
    final DocumentReference docRef = db.collection("cities").document("SF");
    ApiFuture<String> transaction = db.runTransaction(new Transaction.Function<String>() {

        @Override
        public String updateCallback(Transaction transaction) throws Exception {
            DocumentSnapshot snapshot = transaction.get(docRef).get();
            Long newPopulation = snapshot.getLong("population") + 1;
            // conditionally update based on current population
            if (newPopulation <= 1000000L) {
                transaction.update(docRef, "population", newPopulation);
                return "Population increased to " + newPopulation;
            } else {
                throw new Exception("Sorry! Population is too big.");
            }
        }
    });
    // Print information retrieved from transaction
    System.out.println(transaction.get());
    // [END fs_return_info_transaction]
    return transaction.get();
}