Eliminate reference cycles to improve Ctx cleanup

tiledb/indexing.pxd

@@ -1,6 +1,6 @@
 from .libtiledb cimport Array, ArraySchema, Query
 
 cdef class DomainIndexer:
-    cdef Array array
+    cdef object array_ref
     cdef ArraySchema schema
     cdef Query query

tiledb/indexing.pyx

@@ -4,6 +4,7 @@ IF TILEDBPY_MODULAR:
 
 import numpy as np
 from .array import DenseArray, SparseArray
+import weakref
 
 def _index_as_tuple(idx):
     """Forces scalar index objects to a tuple representation"""
@@ -25,14 +26,21 @@ cdef class DomainIndexer(object):
         return indexer
 
     def __init__(self, Array array, query = None):
-        self.array = array
+        self.array_ref = weakref.ref(array)
         self.schema = array.schema
         self.query = query
 
+    @property
+    def array(self):
+        assert self.array_ref() is not None, \
+            "Internal error: invariant violation (index[] with dead array_ref)"
+        return self.array_ref()
+
     def __getitem__(self, object idx):
         # implements domain-based indexing: slice by domain coordinates, not 0-based python indexing
 
-        cdef Domain dom = self.schema.domain
+        cdef ArraySchema schema = self.array.schema
+        cdef Domain dom = schema.domain
         cdef ndim = dom.ndim
         cdef list attr_names = list()
 
@@ -59,7 +67,7 @@ cdef class DomainIndexer(object):
             assert isinstance(subidx, slice)
             subarray[i] = subidx.start, subidx.stop
 
-        attr_names = list(self.schema.attr(i).name for i in range(self.schema.nattr))
+        attr_names = list(schema.attr(i).name for i in range(schema.nattr))
 
         order = None
         # TODO make coords optional for array.domain_index. there are no kwargs in slicing[], so
@@ -85,7 +93,6 @@ cdef class DomainIndexer(object):
         else:
             raise ValueError("order must be 'C' (TILEDB_ROW_MAJOR), 'F' (TILEDB_COL_MAJOR), or 'G' (TILEDB_GLOBAL_ORDER)")
 
-
         if isinstance(self.array, SparseArray):
             return (<SparseArrayImpl>self.array)._read_sparse_subarray(subarray, attr_names, layout)
         elif isinstance(self.array, DenseArray):

tiledb/libtiledb.pxd

@@ -1098,6 +1098,7 @@ cdef class ArraySchema(object):
     cdef _attr_idx(self, int idx)
 
 cdef class Array(object):
+    cdef object __weakref__
     cdef Ctx ctx
     cdef tiledb_array_t* ptr
     cdef unicode uri
@@ -1106,13 +1107,11 @@ cdef class Array(object):
     cdef object view_attr # can be None
     cdef object key # can be None
     cdef object schema
-    cdef DomainIndexer domain_index
 
-    # TODO make this a cython type TBD
+    cdef DomainIndexer domain_index
     cdef object multi_index
-
-    cdef object last_fragment_info
     cdef Metadata meta
+    cdef object last_fragment_info
 
     cdef _ndarray_is_varlen(self, np.ndarray array)
     cdef _unpack_varlen_query(self, ReadQuery read, unicode name)
@@ -1149,7 +1148,7 @@ cdef class ReadQuery(object):
     cdef object _offsets
 
 cdef class Metadata(object):
-    cdef Array array
+    cdef object array_ref
 
 cdef class TileDBError(Exception):
     pass

tiledb/metadata.pyx

@@ -3,6 +3,8 @@ IF TILEDBPY_MODULAR:
     from .libtiledb import *
     from .libtiledb cimport *
 
+import weakref
+
 from cython.operator cimport dereference as deref
 from cpython.long cimport PyLong_AsLongLong
 from cpython.float cimport PyFloat_AsDouble
@@ -15,8 +17,6 @@ cdef extern from "<utility>" namespace "std" nogil:
     cdef unique_ptr[vector[char]] move(unique_ptr[vector[char]])
     #cdef unique_ptr[vector[char]] make_unique(vector[char])
 
-
-
 cdef object metadata_value_check(val):
     if isinstance(val, int):
         if val > numeric_limits[int64_t].max():
@@ -168,10 +168,12 @@ cdef object unpack_metadata_val(tiledb_datatype_t value_type,
     return None
 
 
-cdef object put_metadata(tiledb_ctx_t* ctx_ptr,
-                         tiledb_array_t* array_ptr,
+cdef object put_metadata(Array array,
                          key, val):
 
+    cdef tiledb_array_t* array_ptr = array.ptr
+    cdef tiledb_ctx_t* ctx_ptr = array.ctx.ptr
+
     cdef int rc = TILEDB_OK
     cdef vector[char] data_buf = vector[char]()
     cdef const char* key_cstr
@@ -200,10 +202,12 @@ cdef object put_metadata(tiledb_ctx_t* ctx_ptr,
 
     return None
 
-cdef object get_metadata(tiledb_ctx_t* ctx_ptr,
-                         tiledb_array_t* array_ptr,
+cdef object get_metadata(array: Array,
                          key: unicode):
 
+    cdef tiledb_array_t* array_ptr = array.ptr
+    cdef tiledb_ctx_t* ctx_ptr = array.ctx.ptr
+
     cdef:
         const char* key_ptr
         object key_utf8
@@ -231,12 +235,12 @@ cdef object get_metadata(tiledb_ctx_t* ctx_ptr,
 
     return unpack_metadata_val(value_type, value_num, value)
 
-cdef put_metadata_dict(tiledb_ctx_t* ctx_ptr, tiledb_array_t* array_ptr, kv):
+cdef put_metadata_dict(Array array, kv):
 
     for k,v in kv.iteritems():
-        put_metadata(ctx_ptr, array_ptr, k, v)
+        put_metadata(array, k, v)
 
-cdef object load_metadata(tiledb_ctx_t* ctx_ptr, tiledb_array_t* array_ptr, unpack=True):
+cdef object load_metadata(Array array, unpack=True):
     """
     Load array metadata dict or keys
 
@@ -245,6 +249,8 @@ cdef object load_metadata(tiledb_ctx_t* ctx_ptr, tiledb_array_t* array_ptr, unpa
     :param unpack: unpack the values into dictionary
     :return: dict(k: v) if unpack else list(k)
     """
+    cdef tiledb_ctx_t* ctx_ptr = array.ctx.ptr
+    cdef tiledb_array_t* array_ptr = array.ptr
 
     cdef uint64_t metadata_num
     rc = tiledb_array_get_metadata_num(ctx_ptr, array_ptr, &metadata_num)
@@ -296,9 +302,14 @@ cdef object load_metadata(tiledb_ctx_t* ctx_ptr, tiledb_array_t* array_ptr, unpa
 
 
 cdef class Metadata(object):
-
     def __init__(self, array):
-        self.array = array
+        self.array_ref = weakref.ref(array)
+
+    @property
+    def array(self):
+        assert self.array_ref() is not None, \
+            "Internal error: invariant violation ([] from gc'd Array)"
+        return self.array_ref()
 
     def __setitem__(self, key, value):
         """
@@ -312,7 +323,7 @@ cdef class Metadata(object):
             raise ValueError("Unexpected key type '{}': expected str "
                              "type".format(type(key)))
 
-        put_metadata(self.array.ctx.ptr, self.array.ptr, key, value)
+        put_metadata(self.array, key, value)
 
     def __getitem__(self, key):
         """
@@ -326,7 +337,7 @@ cdef class Metadata(object):
 
         # `get_metadata` expects unicode
         key = ustring(key)
-        v = get_metadata(self.array.ctx.ptr, self.array.ptr, key)
+        v = get_metadata(self.array, key)
 
         if v is None:
             raise TileDBError("Failed to unpack value for key: '{}'".format(key))
@@ -359,15 +370,16 @@ cdef class Metadata(object):
         # TODO: ensure that the array is not x-locked?
 
         cdef uint32_t rc = 0
-
+        cdef tiledb_ctx_t* ctx_ptr = (<Array?>self.array).ctx.ptr
         cdef:
             tiledb_encryption_type_t key_type = TILEDB_NO_ENCRYPTION
             void* key_ptr = NULL
             uint32_t key_len = 0
         cdef bytes bkey
 
         cdef bytes buri = unicode_path(self.array.uri)
-        if self.array.key is not None:
+        cdef unicode key = (<Array?>self.array).key
+        if key is not None:
             if isinstance(self.array.key, str):
                 bkey = self.array.key.encode('ascii')
             else:
@@ -378,15 +390,15 @@ cdef class Metadata(object):
             key_len = <uint32_t> PyBytes_GET_SIZE(bkey)
 
         rc = tiledb_array_consolidate_metadata_with_key(
-                self.array.ctx.ptr,
+                ctx_ptr,
                 buri,
                 key_type,
                 key_ptr,
                 key_len,
                 NULL)
 
         if rc != TILEDB_OK:
-            _raise_ctx_err(self.array.ctx.ptr, rc)
+            _raise_ctx_err(ctx_ptr, rc)
 
     def __delitem__(self, key):
         """
@@ -400,29 +412,30 @@ cdef class Metadata(object):
         :param key:
         :return:
         """
-        cdef:
-            tiledb_ctx_t* ctx_ptr = self.array.ctx.ptr
-            const char* key_ptr
-            object key_utf8
-            int32_t rc
+        cdef tiledb_ctx_t*  ctx_ptr = (<Array>self.array).ctx.ptr
+        cdef tiledb_array_t*  array_ptr = (<Array>self.array).ptr
+        cdef const char* key_ptr
+        cdef object key_utf8
+        cdef int32_t rc
 
         key_utf8 = key.encode('UTF-8')
         key_ptr = <const char*>key_utf8
 
-        rc = tiledb_array_delete_metadata(self.array.ctx.ptr, self.array.ptr, key_ptr)
+        rc = tiledb_array_delete_metadata(ctx_ptr, array_ptr, key_ptr)
         if rc != TILEDB_OK:
             _raise_ctx_err(ctx_ptr, rc)
 
     def __len__(self):
-        cdef:
-            int32_t rc
-            uint64_t num
+        cdef tiledb_ctx_t*  ctx_ptr = (<Array>self.array).ctx.ptr
+        cdef tiledb_array_t*  array_ptr = (<Array>self.array).ptr
+        cdef int32_t rc
+        cdef uint64_t num
 
         rc = tiledb_array_get_metadata_num(
-                self.array.ctx.ptr, self.array.ptr, &num)
+                ctx_ptr, array_ptr, &num)
 
         if rc != TILEDB_OK:
-            _raise_ctx_err(self.array.ctx.ptr, rc)
+            _raise_ctx_err(ctx_ptr, rc)
 
         return <int>num
 
@@ -432,20 +445,19 @@ cdef class Metadata(object):
 
         :return: List of keys
         """
-        return load_metadata(self.array.ctx.ptr, self.array.ptr, unpack=False)
+        return load_metadata(self.array, unpack=False)
 
     def values(self):
         # TODO this should be an iterator
-
-        data = load_metadata(self.array.ctx.ptr, self.array.ptr, unpack=True)
+        data = load_metadata(self.array, unpack=False)
         return data.values()
 
     def pop(self, key, default=None):
         raise NotImplementedError("dict.pop requires read-write access to array")
 
     def items(self):
         # TODO this should be an iterator
-        data = load_metadata(self.array.ctx.ptr, self.array.ptr, unpack=True)
+        data = load_metadata(self.array, unpack=True)
         return tuple( (k, data[k]) for k in data.keys() )
 
     def _set_numpy(self, key, np.ndarray arr, datatype = None):
@@ -458,6 +470,8 @@ cdef class Metadata(object):
         :param arr: 1d NumPy ndarray
         :return:
         """
+        cdef tiledb_ctx_t*  ctx_ptr = (<Array>self.array).ctx.ptr
+        cdef tiledb_array_t*  array_ptr = (<Array>self.array).ptr
 
         cdef:
             int32_t rc = TILEDB_OK
@@ -489,12 +503,12 @@ cdef class Metadata(object):
         cdef const char* data_ptr = <const char*>np.PyArray_DATA(arr)
 
         rc = tiledb_array_put_metadata(
-                self.array.ctx.ptr,
-                self.array.ptr,
+                ctx_ptr,
+                array_ptr,
                 key_cstr,
                 tiledb_type,
                 value_num,
                 data_ptr)
 
         if rc != TILEDB_OK:
-            _raise_ctx_err(self.array.ctx.ptr, rc)
+            _raise_ctx_err(ctx_ptr, rc)

tiledb/multirange_indexing.py

@@ -1,7 +1,7 @@
 import tiledb
 from tiledb import Array, ArraySchema
 import os, numpy as np
-import sys
+import sys, weakref
 
 try:
     from tiledb.libtiledb import multi_index
@@ -74,12 +74,16 @@ class MultiRangeIndexer(object):
     #def __init__(self, array: Array, query = None):
 
     def __init__(self, array, query = None):
-        self.array = array
-        # TODO remove
-        if hasattr(array, 'schema'):
-            self.schema = array.schema
+        self.array_ref = weakref.ref(array)
+        self.schema = array.schema
         self.query = query
 
+    @property
+    def array(self):
+        assert self.array_ref() is not None, \
+            "Internal error: invariant violation (indexing call w/ dead array_ref)"
+        return self.array_ref()
+
     def getitem_ranges(self, idx):
         dom = self.schema.domain
         ndim = dom.ndim