rocksq.nonblocking

class rocksq.nonblocking.PersistentQueueWithCapacity(path, max_elements=1000000000, max_inflight_ops=1000)

A persistent queue with a fixed capacity. This is a non-blocking implementation. All methods return the future-like object Response which must be used to get the actual response.

Parameters:

path (str) – The path to the queue.
max_elements (int) – The maximum number of elements the queue can hold. Default to 1_000_000_000.
max_inflight_ops (int) – The maximum number of inflight operations. If the number of inflight operations reached its limit, further ops are blocked until the capacity is available. Default to 1_000.

Raises:

PyRuntimeError – If the queue could not be created.

disk_size

Returns the disk size of the queue.

Raises:: PyRuntimeError –
Returns:: The future-like object which must be used to get the actual response. For the size operation, the response object is useful to call for is_ready(), try_get() and get().
Return type:: Response

inflight_ops

len

Returns the length of the queue.

Raises:: PyRuntimeError – If the method fails.
Returns:: The future-like object which must be used to get the actual response. For the length operation, the response object is useful to call for is_ready(), try_get() and get().
Return type:: Response

payload_size

Returns the payload size of the queue.

Raises:: PyRuntimeError –
Returns:: The future-like object which must be used to get the actual response. For the size operation, the response object is useful to call for is_ready(), try_get() and get().
Return type:: Response

pop(max_elements=1, no_gil=True)

Retrieves items from the queue.

GIL: the method can optionally be called without the GIL.

Parameters:

max_elements (int) – The maximum number of elements to retrieve. Default to 1.
no_gil (bool) – If True, the method will be called without the GIL. Default is True.

Raises:

PyRuntimeError – If the method fails.

Returns:

The future-like object which must be used to get the actual response. For the pop operation, the response object is useful to call for is_ready(), try_get() and get().

Return type:

Response

push(items, no_gil=True)

Adds items to the queue.

GIL: the method can optionally be called without the GIL.

Parameters:

items (list of bytes) – The items to add to the queue.
no_gil (bool) – If True, the method will be called without the GIL. Default is True.

Raises:

PyRuntimeError – If the method fails.

Returns:

The future-like object which must be used to get the actual response. For the push operation, the response object is only useful to call for is_ready().

Return type:

Response

class rocksq.nonblocking.Response

get()

Returns the response in a blocking way.

GIL: the method releases the GIL

Raises:: PyRuntimeError – If the method fails.
Returns:: The response when it is ready.
Return type:: ResponseVariant

is_ready

Checks if the response is ready.

Returns:: True if the response is ready, False otherwise.
Return type:: bool

try_get()

Returns the response if it is ready.

Raises:

PyRuntimeError – If the method fails.

Returns:

ResponseVariant – The response if it is ready,
None – otherwise.

class rocksq.nonblocking.ResponseVariant

A response variant containing the actual data for push, pop, size and length operations. The object is created only by the library, there is no public constructor.

data

Returns the data for the pop() operation.

Raises:

PyRuntimeError – If the method fails.

Returns:

list of bytes – The data for the pop() operation if the operation was successful,
None – if the future doesn’t represent the pop() operation.

len

Returns the length of the queue.

Raises:

PyRuntimeError – If the method fails.

Returns:

int – The length of the queue if the operation was successful,
None – if the future doesn’t represent the length() operation.

size

Returns the size of the queue.

Raises:

PyRuntimeError – If the method fails.

Returns:

int – The size of the queue if the operation was successful,
None – if the future doesn’t represent the size() operation.