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): """ Returns the Records from this table that match the given field=value arguments. If `sort_by=field` is given, sort the results by that field. For example: ``` People.lookupRecords(Last_Name="Johnson", sort_by="First_Name") People.lookupRecords(First_Name="George", Last_Name="Washington") ``` See [RecordSet](#recordset) for useful properties offered by the returned object. """ return self.table.lookup_records(**field_value_pairs) def lookupOne(self, **field_value_pairs): """ Returns a Record matching the given field=value arguments. 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") ``` """ 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 return summary_table.lookupOrAddDerived(**{c: getattr(rec, c) for c in groupby_cols}) 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): result += self._engine.user_actions.BulkAddRecord( summary_table.table_id, new_row_ids, values_to_add ) 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. 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) 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: 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]