gristlabs_grist-core/sandbox/grist/table.py
2022-02-14 08:21:42 -05:00

597 lines
24 KiB
Python

import collections
import itertools
import types
import six
from six.moves import xrange
import column
import depend
import docmodel
import logger
import lookup
import records
import relation as relation_module # "relation" is used too much as a variable name below.
import usertypes
log = logger.Logger(__name__, logger.INFO)
def _make_sample_record(table_id, col_objs):
"""
Helper to create a sample record for a table, used for auto-completions.
"""
# This type gets created with a property for each column. We use property-methods rather than
# plain properties because this sample record is created before all tables have initialized, so
# reference values (using .sample_record for other tables) are not yet available.
RecType = type(table_id, (), {
# Note col=col to bind col at lambda-creation time; see
# https://stackoverflow.com/questions/10452770/python-lambdas-binding-to-local-values
col.col_id: property(lambda self, col=col: col.sample_value())
for col in col_objs
if column.is_user_column(col.col_id) or col.col_id == 'id'
})
return RecType()
def get_default_func_name(col_id):
return "_default_" + col_id
def get_validation_func_name(index):
return "validation___%d" % index
class UserTable(object):
"""
Each data table in the document is represented in the code by an instance of `UserTable` class.
These names are always capitalized. A UserTable provides access to all the records in the table,
as well as methods to look up particular records.
Every table in the document is available to all formulas.
"""
# UserTables are only created in auto-generated code by using UserTable as decorator for a table
# model class. I.e.
#
# @grist.UserTable
# class Students:
# ...
#
# makes the "Students" identifier an actual UserTable instance, so that Students.lookupRecords
# and so on can be used.
def __init__(self, model_class):
docmodel.enhance_model(model_class)
self.Model = model_class
column_ids = {col for col in model_class.__dict__ if not col.startswith("_")}
column_ids.add('id')
self.table = None
def _set_table_impl(self, table_impl):
self.table = table_impl
@property
def Record(self):
return self.table.Record
@property
def RecordSet(self):
return self.table.RecordSet
# Note these methods are named camelCase since they are a public interface exposed to formulas,
# and we decided camelCase was a more user-friendly choice for user-facing functions.
def lookupRecords(self, **field_value_pairs):
"""
Name: lookupRecords
Usage: UserTable.__lookupRecords__(Field_In_Lookup_Table=value, ...)
Returns a [RecordSet](#recordset) matching the given field=value arguments. The value may be any expression,
most commonly a field in the current row (e.g. `$SomeField`) or a constant (e.g. a quoted string
like `"Some Value"`) (examples below).
If `sort_by=field` is given, sort the results by that field.
For example:
```
People.lookupRecords(Email=$Work_Email)
People.lookupRecords(First_Name="George", Last_Name="Washington")
People.lookupRecords(Last_Name="Johnson", sort_by="First_Name")
```
See [RecordSet](#recordset) for useful properties offered by the returned object.
See [CONTAINS](#contains) for an example utilizing `UserTable.lookupRecords` to find records
where a field of a list type (such as `Choice List` or `Reference List`) contains the given
value.
"""
return self.table.lookup_records(**field_value_pairs)
def lookupOne(self, **field_value_pairs):
"""
Name: lookupOne
Usage: UserTable.__lookupOne__(Field_In_Lookup_Table=value, ...)
Returns a [Record](#record) matching the given field=value arguments. The value may be any expression,
most commonly a field in the current row (e.g. `$SomeField`) or a constant (e.g. a quoted string
like `"Some Value"`). If multiple records match, returns one of them. If none match, returns the
special empty record.
For example:
```
People.lookupOne(First_Name="Lewis", Last_Name="Carroll")
People.lookupOne(Email=$Work_Email)
```
"""
return self.table.lookup_one_record(**field_value_pairs)
def lookupOrAddDerived(self, **kwargs):
return self.table.lookupOrAddDerived(**kwargs)
def getSummarySourceGroup(self, rec):
return self.table.getSummarySourceGroup(rec)
@property
def all(self):
"""
Name: all
Usage: UserTable.__all__
The list of all the records in this table.
For example, this evaluates to the number of records in the table `Students`.
```
len(Students.all)
```
This evaluates to the sum of the `Population` field for every record in the table `Countries`.
```
sum(r.Population for r in Countries.all)
```
"""
return self.lookupRecords()
def __dir__(self):
# Suppress member properties when listing dir(TableClass). This affects rlcompleter, with the
# result that auto-complete will only return class properties, not member properties added in
# the constructor.
return []
class Table(object):
"""
Table represents a table with all its columns and data.
"""
class RowIDs(object):
"""
Helper container that represents the set of valid row IDs in this table.
"""
def __init__(self, id_column):
self._id_column = id_column
def __contains__(self, row_id):
return row_id < self._id_column.size() and self._id_column.raw_get(row_id) > 0
def __iter__(self):
for row_id in xrange(self._id_column.size()):
if self._id_column.raw_get(row_id) > 0:
yield row_id
def max(self):
last = self._id_column.size() - 1
while last > 0 and last not in self:
last -= 1
return last
def __init__(self, table_id, engine):
# The id of the table is the name of its class.
self.table_id = table_id
# Each table maintains a reference to the engine that owns it.
self._engine = engine
# The UserTable object for this table, set in _rebuild_model
self.user_table = None
# Store the identity Relation for this table.
self._identity_relation = relation_module.IdentityRelation(table_id)
# Set of ReferenceColumn objects that refer to this table
self._back_references = set()
# Store the constant Node for "new columns". Accessing invalid columns creates a dependency
# on this node, and triggers recomputation when columns are added or renamed.
self._new_columns_node = depend.Node(self.table_id, None)
# Collection of special columns that this table maintains, which include LookupMapColumns
# and formula columns for maintaining summary tables. These persist across table rebuilds, and
# get cleaned up with delete_column().
self._special_cols = {}
# Maintain Column objects both as a mapping from col_id and as an ordered list.
self.all_columns = collections.OrderedDict()
# This column is always present.
self._id_column = column.create_column(self, 'id', column.get_col_info(usertypes.Id()))
# The `row_ids` member offers some useful interfaces:
# * if row_id in table.row_ids
# * for row_id in table.row_ids
self.row_ids = self.RowIDs(self._id_column)
# For a summary table, this is a reference to the Table object for the source table.
self._summary_source_table = None
# For a summary table, the name of the special helper column auto-added to the source table.
self._summary_helper_col_id = None
# For a summary table, True in the common case where every source record belongs
# to just one group in the summary table, False if grouping by list columns
# which are 'flattened' so source records may appear in multiple groups
self._summary_simple = None
# Add Record and RecordSet subclasses which fill in this table as the first argument
class Record(records.Record):
def __init__(inner_self, *args, **kwargs): # pylint: disable=no-self-argument
super(Record, inner_self).__init__(self, *args, **kwargs)
class RecordSet(records.RecordSet):
def __init__(inner_self, *args, **kwargs): # pylint: disable=no-self-argument
super(RecordSet, inner_self).__init__(self, *args, **kwargs)
self.Record = Record
self.RecordSet = RecordSet
def _rebuild_model(self, user_table):
"""
Sets class-wide properties from a new Model class for the table (inner class within the table
class), and rebuilds self.all_columns from the new Model, reusing columns with existing names.
"""
self.user_table = user_table
self.Model = user_table.Model
new_cols = collections.OrderedDict()
new_cols['id'] = self._id_column
# List of Columns in the same order as they appear in the generated Model definition.
col_items = [c for c in six.iteritems(self.Model.__dict__) if not c[0].startswith("_")]
col_items.sort(key=lambda c: self._get_sort_order(c[1]))
for col_id, col_model in col_items:
default_func = self.Model.__dict__.get(get_default_func_name(col_id))
new_cols[col_id] = self._create_or_update_col(col_id, col_model, default_func)
# Used for auto-completion as a record with correct properties of correct types.
self.sample_record = _make_sample_record(self.table_id, six.itervalues(new_cols))
# Note that we reuse previous special columns like lookup maps, since those not affected by
# column changes should stay the same. These get removed when unneeded using other means.
new_cols.update(sorted(six.iteritems(self._special_cols)))
# Set the new columns.
self.all_columns = new_cols
# Make sure any new columns get resized to the full table size.
self.grow_to_max()
# If this is a summary table, auto-create a necessary helper formula in the source table.
summary_src = getattr(self.Model, '_summarySourceTable', None)
if summary_src not in self._engine.tables:
self._summary_source_table = None
self._summary_helper_col_id = None
self._summary_simple = None
else:
self._summary_source_table = self._engine.tables[summary_src]
self._summary_helper_col_id = "#summary#%s" % self.table_id
# Figure out the group-by columns: these are all the non-formula columns.
groupby_cols = tuple(sorted(col_id for (col_id, col_model) in col_items
if not isinstance(col_model, types.FunctionType)))
self._summary_simple = not any(
isinstance(
self._summary_source_table.all_columns.get(group_col),
(column.ChoiceListColumn, column.ReferenceListColumn)
)
for group_col in groupby_cols
)
# Add the special helper column to the source table.
self._summary_source_table._add_update_summary_col(self, groupby_cols)
def _add_update_summary_col(self, summary_table, groupby_cols):
# TODO: things need to be removed also from summary_cols when a summary table is deleted.
# Grouping by list columns is significantly more complex and this comes with a
# performance cost, so in the common case we use the simpler older implementation
# In particular _updateSummary returns (possibly creating) just one reference
# instead of a list, which getSummarySourceGroup looks up directly instead
# of using CONTAINS, which in turn allows using SimpleLookupMapColumn
# instead of the similarly slower and more complicated ContainsLookupMapColumn
# All of these branches should be interchangeable and produce equivalent results
# when no list columns or CONTAINS are involved,
# especially since we need to be able to summarise by a combination of list and non-list
# columns or lookupRecords with a combination of CONTAINS and normal values,
# these are just performance optimisations
if summary_table._summary_simple:
@usertypes.formulaType(usertypes.Reference(summary_table.table_id))
def _updateSummary(rec, table): # pylint: disable=unused-argument
try:
# summary table output should be treated as we treat formula columns, for acl purposes
self._engine.user_actions.enter_indirection()
return summary_table.lookupOrAddDerived(**{c: getattr(rec, c) for c in groupby_cols})
finally:
self._engine.user_actions.leave_indirection()
else:
@usertypes.formulaType(usertypes.ReferenceList(summary_table.table_id))
def _updateSummary(rec, table): # pylint: disable=unused-argument
# Create a row in the summary table for every combination of values in
# list type columns
lookup_values = []
for group_col in groupby_cols:
lookup_value = getattr(rec, group_col)
if isinstance(self.all_columns[group_col],
(column.ChoiceListColumn, column.ReferenceListColumn)):
# Check that ChoiceList/ReferenceList cells have appropriate types.
# Don't iterate over characters of a string.
if isinstance(lookup_value, (six.binary_type, six.text_type)):
return []
try:
# We only care about the unique choices
lookup_value = set(lookup_value)
except TypeError:
return []
else:
lookup_value = [lookup_value]
lookup_values.append(lookup_value)
result = []
values_to_add = {}
new_row_ids = []
for values_tuple in sorted(itertools.product(*lookup_values)):
values_dict = dict(zip(groupby_cols, values_tuple))
row_id = summary_table.lookup_one_record(**values_dict)._row_id
if row_id:
result.append(row_id)
else:
for col, value in six.iteritems(values_dict):
values_to_add.setdefault(col, []).append(value)
new_row_ids.append(None)
if new_row_ids and not self._engine.is_triggered_by_table_action(summary_table.table_id):
try:
# summary table output should be treated as we treat formula columns, for acl purposes
self._engine.user_actions.enter_indirection()
result += self._engine.user_actions.BulkAddRecord(
summary_table.table_id, new_row_ids, values_to_add
)
finally:
self._engine.user_actions.leave_indirection()
return result
_updateSummary.is_private = True
col_id = summary_table._summary_helper_col_id
if self.has_column(col_id):
# If type changed between Reference/ReferenceList, replace completely.
# pylint: disable=unidiomatic-typecheck
if type(self.get_column(col_id).type_obj) != type(_updateSummary.grist_type):
self.delete_column(self.get_column(col_id))
col_obj = self._create_or_update_col(col_id, _updateSummary)
self._special_cols[col_id] = col_obj
self.all_columns[col_id] = col_obj
def get_helper_columns(self):
"""
Returns a list of columns from other tables that are only needed for the sake of this table.
"""
if self._summary_source_table and self._summary_helper_col_id:
helper_col = self._summary_source_table.get_column(self._summary_helper_col_id)
return [helper_col]
return []
def _create_or_update_col(self, col_id, col_model, default_func=None):
"""
Helper to update an existing column with a new model, or create a new column object.
"""
col_info = column.get_col_info(col_model, default_func)
col_obj = self.all_columns.get(col_id)
if col_obj:
# This is important for when a column has NOT changed, since although the formula method is
# unchanged, it's important to use the new instance of it from the newly built module.
col_obj.update_method(col_info.method)
else:
col_obj = column.create_column(self, col_id, col_info)
self._engine.invalidate_column(col_obj)
return col_obj
@staticmethod
def _get_sort_order(col_model):
"""
We sort columns according to the order in which they appear in the model definition. To
detect this order, we sort data columns by _creation_order, and formula columns by the
function's source-code line number.
"""
return ((0, col_model._creation_order)
if not isinstance(col_model, types.FunctionType) else
(1, col_model.__code__.co_firstlineno))
def next_row_id(self):
"""
Returns the ID of the next row that can be added to this table.
"""
return self.row_ids.max() + 1
def grow_to_max(self):
"""
Resizes all columns as needed so that all valid row_ids are valid indices into all columns.
"""
size = self.row_ids.max() + 1
for col_obj in six.itervalues(self.all_columns):
col_obj.growto(size)
def get_column(self, col_id):
"""
Returns the column with the given column ID.
"""
return self.all_columns[col_id]
def has_column(self, col_id):
"""
Returns whether col_id represents a valid column in the table.
"""
return col_id in self.all_columns
def lookup_records(self, **kwargs):
"""
Returns a Record matching the given column=value arguments. It creates the necessary
dependencies, so that the formula will get re-evaluated if needed. It also creates and starts
maintaining a lookup index to make such lookups fast.
"""
# The tuple of keys used determines the LookupMap we need.
sort_by = kwargs.pop('sort_by', None)
key = []
col_ids = []
for col_id in sorted(kwargs):
value = kwargs[col_id]
if isinstance(value, lookup._Contains):
value = value.value
# While users should use CONTAINS on lookup values,
# the marker is moved to col_id so that the LookupMapColumn knows how to
# update its index correctly for that column.
col_id = lookup._Contains(col_id)
else:
col = self.get_column(col_id)
# Convert `value` to the correct type of rich value for that column
value = col._convert_raw_value(col.convert(value))
key.append(value)
col_ids.append(col_id)
col_ids = tuple(col_ids)
key = tuple(key)
lookup_map = self._get_lookup_map(col_ids)
row_id_set, rel = lookup_map.do_lookup(key)
if sort_by:
row_ids = sorted(row_id_set,
key=lambda r: column.SafeSortKey(self._get_col_value(sort_by, r, rel)))
else:
row_ids = sorted(row_id_set)
return self.RecordSet(row_ids, rel, group_by=kwargs, sort_by=sort_by)
def lookup_one_record(self, **kwargs):
return self.lookup_records(**kwargs).get_one()
def _get_lookup_map(self, col_ids_tuple):
"""
Helper which returns the LookupMapColumn for the given combination of lookup columns. A
LookupMap behaves a bit like a formula column in that it depends on the passed-in columns and
gets updated whenever any of them change.
"""
# LookupMapColumn is a Node, so identified by (table_id, col_id) pair, so we make up a col_id
# to identify this lookup object uniquely in this Table.
lookup_col_id = "#lookup#" + ":".join(map(str, col_ids_tuple))
lmap = self._special_cols.get(lookup_col_id)
if not lmap:
# Check that the table actually has all the columns we looking up.
for c in col_ids_tuple:
c = lookup.extract_column_id(c)
if not self.has_column(c):
raise KeyError("Table %s has no column %s" % (self.table_id, c))
if any(isinstance(col_id, lookup._Contains) for col_id in col_ids_tuple):
column_class = lookup.ContainsLookupMapColumn
else:
column_class = lookup.SimpleLookupMapColumn
lmap = column_class(self, lookup_col_id, col_ids_tuple)
self._special_cols[lookup_col_id] = lmap
self.all_columns[lookup_col_id] = lmap
return lmap
def delete_column(self, col_obj):
assert col_obj.table_id == self.table_id
self._special_cols.pop(col_obj.col_id, None)
self.all_columns.pop(col_obj.col_id, None)
def lookupOrAddDerived(self, **kwargs):
record = self.lookup_one_record(**kwargs)
if not record._row_id and not self._engine.is_triggered_by_table_action(self.table_id):
record._row_id = self._engine.user_actions.AddRecord(self.table_id, None, kwargs)
return record
def getSummarySourceGroup(self, rec):
if self._summary_source_table:
# See comment in _add_update_summary_col.
# _summary_source_table._summary_simple determines whether
# the column named self._summary_helper_col_id is a single reference
# or a reference list.
lookup_value = rec if self._summary_simple else lookup._Contains(rec)
return self._summary_source_table.lookup_records(**{
self._summary_helper_col_id: lookup_value
})
else:
return None
def get(self, **kwargs):
"""
Returns the first row_id matching the given column=value arguments. This is intended for grist
internal code rather than for user formulas, because it doesn't create the necessary
dependencies.
"""
# TODO: It should use indices, to avoid linear searching
# TODO: It should create dependencies as needed when used from formulas.
# TODO: It should return Record instead, for convenience of user formulas
col_values = [(self.all_columns[col_id], value) for (col_id, value) in six.iteritems(kwargs)]
for row_id in self.row_ids:
if all(col.raw_get(row_id) == value for col, value in col_values):
return row_id
raise KeyError("'get' found no matching record")
def filter(self, **kwargs):
"""
Generates all row_ids matching the given column=value arguments. This is intended for grist
internal code rather than for user formulas, because it doesn't create the necessary
dependencies. Use filter_records() to generate Record objects instead.
"""
# TODO: It should use indices, to avoid linear searching
# TODO: It should create dependencies as needed when used from formulas.
# TODO: It should return Record instead, for convenience of user formulas
col_values = [(self.all_columns[col_id], value) for (col_id, value) in six.iteritems(kwargs)]
for row_id in self.row_ids:
if all(col.raw_get(row_id) == value for col, value in col_values):
yield row_id
def get_record(self, row_id):
"""
Returns a Record object corresponding to the given row_id. This is intended for grist internal
code rather than user formulas.
"""
# We don't set up any dependencies, so it would be incorrect to use this from formulas.
# We no longer assert, however, since such calls may still happen e.g. while applying
# user-actions caused by formula side-effects (e.g. as trigged by lookupOrAddDerived())
if row_id not in self.row_ids:
raise KeyError("'get_record' found no matching record")
return self.Record(row_id, None)
def filter_records(self, **kwargs):
"""
Generator for Record objects for all the rows matching the given column=value arguments.
This is intended for grist internal code rather than user formula. You may call this with no
arguments to generate all Records in the table.
"""
# See note in get_record() about using this call from formulas.
for row_id in self.filter(**kwargs):
yield self.Record(row_id, None)
# TODO: document everything here.
# Called when record.foo is accessed
def _get_col_value(self, col_id, row_id, relation):
[value] = self._get_col_subset(col_id, [row_id], relation)
return value
def _attribute_error(self, col_id, relation):
self._engine._use_node(self._new_columns_node, relation)
raise AttributeError("Table '%s' has no column '%s'" % (self.table_id, col_id))
# Called when record_set.foo is accessed
def _get_col_subset(self, col_id, row_ids, relation):
col = self.all_columns[col_id]
# creates a dependency and brings formula columns up-to-date.
self._engine._use_node(col.node, relation, row_ids)
# TODO: when column is a reference, support property access in return value
return [records.adjust_record(relation, col.get_cell_value(row_id)) for row_id in row_ids]