add put and get

python/pyarrow/lib.pxd

@@ -330,6 +330,15 @@ cdef class NativeFile:
 cdef get_reader(object source, shared_ptr[RandomAccessFile]* reader)
 cdef get_writer(object source, shared_ptr[OutputStream]* writer)
 
+cdef class SerializedPyObject:
+    cdef:
+        CSerializedPyObject data
+
+    cdef readonly:
+        object base
+
+    cdef _write_to(self, OutputStream* stream)
+
 cdef public object pyarrow_wrap_buffer(const shared_ptr[CBuffer]& buf)
 cdef public object pyarrow_wrap_data_type(const shared_ptr[CDataType]& type)
 cdef public object pyarrow_wrap_field(const shared_ptr[CField]& field)

python/pyarrow/plasma.pyx

@@ -26,7 +26,9 @@ from libcpp.vector cimport vector as c_vector
 from libc.stdint cimport int64_t, uint8_t, uintptr_t
 from cpython.pycapsule cimport *
 
-from pyarrow.lib cimport Buffer, NativeFile, check_status
+import pyarrow
+
+from pyarrow.lib cimport Buffer, NativeFile, check_status, SerializedPyObject
 from pyarrow.includes.libarrow cimport (CMutableBuffer, CBuffer,
                                         CFixedSizeBufferWriter, CStatus)
 
@@ -296,7 +298,7 @@ cdef class PlasmaClient:
         ----------
         object_ids : list
             A list of ObjectIDs used to identify some objects.
-        timeout_ms :int
+        timeout_ms : int
             The number of milliseconds that the get call should block before
             timing out and returning. Pass -1 if the call should block and 0
             if the call should return immediately.
@@ -588,3 +590,17 @@ def connect(store_socket_name, manager_socket_name, int release_delay,
                               result.manager_socket_name,
                               release_delay, num_retries))
     return result
+
+def put(PlasmaClient client, value):
+    cdef ObjectID object_id = ObjectID.from_random()
+    cdef SerializedPyObject serialized = pyarrow.serialize(value)
+    buffer = client.create(object_id, serialized.total_bytes)
+    serialized.write_to(buffer)
+    return object_id
+
+def get(PlasmaClient client, object_ids, timeout_ms=-1):
+    results = []
+    buffers = client.get(object_ids, timeout_ms)
+    for buffer in buffers:
+        results.append(pyarrow.deserialize(buffer))
+    return results

python/pyarrow/serialization.pxi

@@ -135,11 +135,6 @@ cdef class SerializedPyObject:
     """
     Arrow-serialized representation of Python object
     """
-    cdef:
-        CSerializedPyObject data
-
-    cdef readonly:
-        object base
 
     property total_bytes:
 

python/pyarrow/tests/test_plasma.py

@@ -119,7 +119,7 @@ def start_plasma_store(plasma_store_memory=DEFAULT_PLASMA_STORE_MEMORY,
     """
     if use_valgrind and use_profiler:
         raise Exception("Cannot use valgrind and profiler at the same time.")
-    plasma_store_executable = os.path.join(pa.__path__[0], "plasma_store")
+    plasma_store_executable = "plasma_store"
     plasma_store_name = "/tmp/plasma_store{}".format(random_name())
     command = [plasma_store_executable,
                "-s", plasma_store_name,
@@ -273,6 +273,12 @@ def test_get(self):
                 else:
                     assert results[i] is None
 
+    def test_put_and_get(self):
+        value = ["hello", "world", 3, 1.0]
+        object_id = pa.plasma.put(self.plasma_client, value)
+        [result] = pa.plasma.get(self.plasma_client, [object_id])
+        assert result == value
+
     def test_store_arrow_objects(self):
         data = np.random.randn(10, 4)
         # Write an arrow object.