Transactions

For the complete documentation index see: llms.txt

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Jump to the Code block for a combined complete example.

Transactions require:

Python client 16.0.0 and later (multi-record transaction API).
Aerospike Database 8.0.0 and later.
A namespace with strong consistency enabled.

See Create and use transactions and Failed commits for commit failure handling. Python client 19.3.0 adds aerospike.TXN_STATE_COMMIT_FAILED for status checks instead of parsing error message text.

The following example demonstrates create, update, read, and delete operations within a transaction.

Setup

import aerospike
from aerospike_helpers.operations import operations
from aerospike import exception

Connect to the Aerospike cluster.

config = {"hosts": [("127.0.0.1", 3000)], "user": "replace", "password": "replace"}
client = aerospike.client(config)

namespace = "sandbox"
set_ = "demo"

Initialize the transaction.

txn = aerospike.Transaction()
print("Transaction ID is", txn.id)

Write, batch, read, and delete inside the transaction

try:
    policy = {"txn": txn}
    key1 = (namespace, set_, 1)
    client.put(key1, bins={"a": 1}, policy=policy)

    ops = [operations.write("c", 9999)]
    key2 = (namespace, set_, 2)
    keys = [key1, key2]
    client.batch_operate(keys, ops, policy_batch=policy)

    _, _, bins = client.get(key2, policy=policy)
    print("2nd record bins:", bins)

    # Durable delete is required; without it the delete may not commit correctly in the transaction.
    policy["durable_delete"] = True
    client.remove(key2, policy=policy)
except Exception as e:
    print("Command during transaction failed:", e)
    client.abort(txn)
    raise

Commit the transaction

print("Committing transaction", txn.id)
try:
    client.commit(txn)
    print("Transaction committed successfully")
except exception.AerospikeError as e:
    print("commit() failed:", e)
    if e.in_doubt:
        try:
            client.commit(txn)
            print("Transaction committed successfully")
        except exception.AerospikeError as e2:
            if e2.in_doubt:
                print("Recommit still in doubt. Log keys for manual verification.")
            else:
                # Not in doubt after recommit. Retry the entire transaction.
                raise
    else:
        # Not in doubt: verify-fail or other commit failure. Retry the entire transaction.
        raise
except Exception:
    print("Non-Aerospike error during commit. Transaction state may be uncertain.")
    raise

Close the client connection

client.close()

Code block

Expand this section for a single code block to perform CRUD operations.

import aerospike
from aerospike_helpers.operations import operations
from aerospike import exception

config = {"hosts": [("127.0.0.1", 3000)], "user": "replace", "password": "replace"}
client = aerospike.client(config)

namespace = "test"
set_ = "demo"

txn = aerospike.Transaction()
print("Transaction ID is", txn.id)

try:
    # Write one record.
    policy = {
        "txn": txn
    }
    key1 = (namespace, set_, 1)
    client.put(key1, bins={"a": 1}, policy=policy)

    # Write / update records in a batch
    ops = [
        operations.write("c", 9999)
    ]
    key2 = (namespace, set_, 2)
    keys = [key1, key2]
    client.batch_operate(keys, ops, policy_batch=policy)

    # Read the second record
    _, _, bins = client.get(key2, policy=policy)
    print("2nd record bins:", bins)

    # Durable delete is required; without it the delete may not commit correctly in the transaction.
    policy["durable_delete"] = True
    client.remove(key2, policy=policy)
except Exception as e:
    print("Command during transaction failed:", e)
    client.abort(txn)
    raise

print("Committing transaction", txn.id)
try:
    client.commit(txn)
    print("Transaction committed successfully")
except exception.AerospikeError as e:
    print("commit() failed:", e)
    if e.in_doubt:
        try:
            client.commit(txn)
            print("Transaction committed successfully")
        except exception.AerospikeError as e2:
            if e2.in_doubt:
                print("Recommit still in doubt. Log keys for manual verification.")
            else:
                # Not in doubt after recommit. Retry the entire transaction.
                raise
    else:
        # Not in doubt: verify-fail or other commit failure. Retry the entire transaction.
        raise
except Exception:
    print("Non-Aerospike error during commit. Transaction state may be uncertain.")
    raise

client.close()