Python LOOKUP_SEP.join方法代码示例

# 需要导入模块: from django.db.models.constants import LOOKUP_SEP [as 别名]
# 或者: from django.db.models.constants.LOOKUP_SEP import join [as 别名]
def add_q(self, q_object):
        """
        A preprocessor for the internal _add_q(). Responsible for
        splitting the given q_object into where and having parts and
        setting up some internal variables.
        """
        if not self.need_having(q_object):
            where_part, having_parts = q_object, []
        else:
            where_part, having_parts = self.split_having_parts(
                q_object.clone(), q_object.negated)
        # For join promotion this case is doing an AND for the added q_object
        # and existing conditions. So, any existing inner join forces the join
        # type to remain inner. Existing outer joins can however be demoted.
        # (Consider case where rel_a is LOUTER and rel_a__col=1 is added - if
        # rel_a doesn't produce any rows, then the whole condition must fail.
        # So, demotion is OK.
        existing_inner = set(
            (a for a in self.alias_map if self.alias_map[a].join_type == INNER))
        clause, require_inner = self._add_q(where_part, self.used_aliases)
        self.where.add(clause, AND)
        for hp in having_parts:
            clause, _ = self._add_q(hp, self.used_aliases)
            self.having.add(clause, AND)
        self.demote_joins(existing_inner) 

# 需要导入模块: from django.db.models.constants import LOOKUP_SEP [as 别名]
# 或者: from django.db.models.constants.LOOKUP_SEP import join [as 别名]
def trim_joins(self, targets, joins, path):
        """
        The 'target' parameter is the final field being joined to, 'joins'
        is the full list of join aliases. The 'path' contain the PathInfos
        used to create the joins.

        Returns the final target field and table alias and the new active
        joins.

        We will always trim any direct join if we have the target column
        available already in the previous table. Reverse joins can't be
        trimmed as we don't know if there is anything on the other side of
        the join.
        """
        joins = joins[:]
        for pos, info in enumerate(reversed(path)):
            if len(joins) == 1 or not info.direct:
                break
            join_targets = set(t.column for t in info.join_field.foreign_related_fields)
            cur_targets = set(t.column for t in targets)
            if not cur_targets.issubset(join_targets):
                break
            targets = tuple(r[0] for r in info.join_field.related_fields if r[1].column in cur_targets)
            self.unref_alias(joins.pop())
        return targets, joins[-1], joins 

# 需要导入模块: from django.db.models.constants import LOOKUP_SEP [as 别名]
# 或者: from django.db.models.constants.LOOKUP_SEP import join [as 别名]
def unquote(s):
    """
    Undo the effects of quote(). Based heavily on urllib.unquote().
    """
    mychr = chr
    myatoi = int
    list = s.split('_')
    res = [list[0]]
    myappend = res.append
    del list[0]
    for item in list:
        if item[1:2]:
            try:
                myappend(mychr(myatoi(item[:2], 16)) + item[2:])
            except ValueError:
                myappend('_' + item)
        else:
            myappend('_' + item)
    return "".join(res) 

# 需要导入模块: from django.db.models.constants import LOOKUP_SEP [as 别名]
# 或者: from django.db.models.constants.LOOKUP_SEP import join [as 别名]
def construct_change_message(self, request, form, formsets):
        """
        Construct a change message from a changed object.
        """
        change_message = []
        if form.changed_data:
            change_message.append(_('Changed %s.') % get_text_list(form.changed_data, _('and')))

        if formsets:
            for formset in formsets:
                for added_object in formset.new_objects:
                    change_message.append(_('Added %(name)s "%(object)s".')
                                          % {'name': force_text(added_object._meta.verbose_name),
                                             'object': force_text(added_object)})
                for changed_object, changed_fields in formset.changed_objects:
                    change_message.append(_('Changed %(list)s for %(name)s "%(object)s".')
                                          % {'list': get_text_list(changed_fields, _('and')),
                                             'name': force_text(changed_object._meta.verbose_name),
                                             'object': force_text(changed_object)})
                for deleted_object in formset.deleted_objects:
                    change_message.append(_('Deleted %(name)s "%(object)s".')
                                          % {'name': force_text(deleted_object._meta.verbose_name),
                                             'object': force_text(deleted_object)})
        change_message = ' '.join(change_message)
        return change_message or _('No fields changed.') 

# 需要导入模块: from django.db.models.constants import LOOKUP_SEP [as 别名]
# 或者: from django.db.models.constants.LOOKUP_SEP import join [as 别名]
def message_user(self, request, message, level=messages.INFO, extra_tags='',
                     fail_silently=False):
        """
        Send a message to the user. The default implementation
        posts a message using the django.contrib.messages backend.

        Exposes almost the same API as messages.add_message(), but accepts the
        positional arguments in a different order to maintain backwards
        compatibility. For convenience, it accepts the `level` argument as
        a string rather than the usual level number.
        """

        if not isinstance(level, int):
            # attempt to get the level if passed a string
            try:
                level = getattr(messages.constants, level.upper())
            except AttributeError:
                levels = messages.constants.DEFAULT_TAGS.values()
                levels_repr = ', '.join('`%s`' % l for l in levels)
                raise ValueError('Bad message level string: `%s`. '
                        'Possible values are: %s' % (level, levels_repr))

        messages.add_message(request, level, message, extra_tags=extra_tags,
                fail_silently=fail_silently) 

# 需要导入模块: from django.db.models.constants import LOOKUP_SEP [as 别名]
# 或者: from django.db.models.constants.LOOKUP_SEP import join [as 别名]
def as_sql(self):
        """
        Create the SQL for this query. Return the SQL string and list of
        parameters.
        """
        sql, params = [], []
        for annotation in self.query.annotation_select.values():
            ann_sql, ann_params = self.compile(annotation, select_format=FORCE)
            sql.append(ann_sql)
            params.extend(ann_params)
        self.col_count = len(self.query.annotation_select)
        sql = ', '.join(sql)
        params = tuple(params)

        sql = 'SELECT %s FROM (%s) subquery' % (sql, self.query.subquery)
        params = params + self.query.sub_params
        return sql, params 

# 需要导入模块: from django.db.models.constants import LOOKUP_SEP [as 别名]
# 或者: from django.db.models.constants.LOOKUP_SEP import join [as 别名]
def demote_joins(self, aliases):
        """
        Change join type from LOUTER to INNER for all joins in aliases.

        Similarly to promote_joins(), this method must ensure no join chains
        containing first an outer, then an inner join are generated. If we
        are demoting b->c join in chain a LOUTER b LOUTER c then we must
        demote a->b automatically, or otherwise the demotion of b->c doesn't
        actually change anything in the query results. .
        """
        aliases = list(aliases)
        while aliases:
            alias = aliases.pop(0)
            if self.alias_map[alias].join_type == LOUTER:
                self.alias_map[alias] = self.alias_map[alias].demote()
                parent_alias = self.alias_map[alias].parent_alias
                if self.alias_map[parent_alias].join_type == INNER:
                    aliases.append(parent_alias) 

# 需要导入模块: from django.db.models.constants import LOOKUP_SEP [as 别名]
# 或者: from django.db.models.constants.LOOKUP_SEP import join [as 别名]
def unquote(s):
    """Undo the effects of quote(). Based heavily on urllib.parse.unquote()."""
    mychr = chr
    myatoi = int
    list = s.split('_')
    res = [list[0]]
    myappend = res.append
    del list[0]
    for item in list:
        if item[1:2]:
            try:
                myappend(mychr(myatoi(item[:2], 16)) + item[2:])
            except ValueError:
                myappend('_' + item)
        else:
            myappend('_' + item)
    return "".join(res) 

# 需要导入模块: from django.db.models.constants import LOOKUP_SEP [as 别名]
# 或者: from django.db.models.constants.LOOKUP_SEP import join [as 别名]
def display_for_value(value, empty_value_display, boolean=False):
    from django.contrib.admin.templatetags.admin_list import _boolean_icon

    if boolean:
        return _boolean_icon(value)
    elif value is None:
        return empty_value_display
    elif isinstance(value, datetime.datetime):
        return formats.localize(timezone.template_localtime(value))
    elif isinstance(value, (datetime.date, datetime.time)):
        return formats.localize(value)
    elif isinstance(value, (int, decimal.Decimal, float)):
        return formats.number_format(value)
    elif isinstance(value, (list, tuple)):
        return ', '.join(str(v) for v in value)
    else:
        return str(value) 

# 需要导入模块: from django.db.models.constants import LOOKUP_SEP [as 别名]
# 或者: from django.db.models.constants.LOOKUP_SEP import join [as 别名]
def message_user(self, request, message, level=messages.INFO, extra_tags='',
                     fail_silently=False):
        """
        Send a message to the user. The default implementation
        posts a message using the django.contrib.messages backend.

        Exposes almost the same API as messages.add_message(), but accepts the
        positional arguments in a different order to maintain backwards
        compatibility. For convenience, it accepts the `level` argument as
        a string rather than the usual level number.
        """
        if not isinstance(level, int):
            # attempt to get the level if passed a string
            try:
                level = getattr(messages.constants, level.upper())
            except AttributeError:
                levels = messages.constants.DEFAULT_TAGS.values()
                levels_repr = ', '.join('`%s`' % l for l in levels)
                raise ValueError(
                    'Bad message level string: `%s`. Possible values are: %s'
                    % (level, levels_repr)
                )

        messages.add_message(request, level, message, extra_tags=extra_tags, fail_silently=fail_silently) 

# 需要导入模块: from django.db.models.constants import LOOKUP_SEP [as 别名]
# 或者: from django.db.models.constants.LOOKUP_SEP import join [as 别名]
def add_q(self, q_object):
        """
        A preprocessor for the internal _add_q(). Responsible for doing final
        join promotion.
        """
        # For join promotion this case is doing an AND for the added q_object
        # and existing conditions. So, any existing inner join forces the join
        # type to remain inner. Existing outer joins can however be demoted.
        # (Consider case where rel_a is LOUTER and rel_a__col=1 is added - if
        # rel_a doesn't produce any rows, then the whole condition must fail.
        # So, demotion is OK.
        existing_inner = {a for a in self.alias_map if self.alias_map[a].join_type == INNER}
        clause, _ = self._add_q(q_object, self.used_aliases)
        if clause:
            self.where.add(clause, AND)
        self.demote_joins(existing_inner) 

# 需要导入模块: from django.db.models.constants import LOOKUP_SEP [as 别名]
# 或者: from django.db.models.constants.LOOKUP_SEP import join [as 别名]
def deferred_class_factory(model, attrs):
    """
    Returns a class object that is a copy of "model" with the specified "attrs"
    being replaced with DeferredAttribute objects. The "pk_value" ties the
    deferred attributes to a particular instance of the model.
    """
    if not attrs:
        return model
    # Never create deferred models based on deferred model
    if model._deferred:
        # Deferred models are proxies for the non-deferred model. We never
        # create chains of defers => proxy_for_model is the non-deferred
        # model.
        model = model._meta.proxy_for_model
    # The app registry wants a unique name for each model, otherwise the new
    # class won't be created (we get an exception). Therefore, we generate
    # the name using the passed in attrs. It's OK to reuse an existing class
    # object if the attrs are identical.
    name = "%s_Deferred_%s" % (model.__name__, '_'.join(sorted(list(attrs))))
    name = utils.truncate_name(name, 80, 32)

    try:
        return apps.get_model(model._meta.app_label, name)

    except LookupError:

        class Meta:
            proxy = True
            app_label = model._meta.app_label

        overrides = {attr: DeferredAttribute(attr, model) for attr in attrs}
        overrides["Meta"] = Meta
        overrides["__module__"] = model.__module__
        overrides["_deferred"] = True
        return type(str(name), (model,), overrides)


# The above function is also used to unpickle model instances with deferred
# fields. 

# 需要导入模块: from django.db.models.constants import LOOKUP_SEP [as 别名]
# 或者: from django.db.models.constants.LOOKUP_SEP import join [as 别名]
def refs_aggregate(lookup_parts, aggregates):
    """
    A little helper method to check if the lookup_parts contains references
    to the given aggregates set. Because the LOOKUP_SEP is contained in the
    default annotation names we must check each prefix of the lookup_parts
    for a match.
    """
    for n in range(len(lookup_parts) + 1):
        level_n_lookup = LOOKUP_SEP.join(lookup_parts[0:n])
        if level_n_lookup in aggregates and aggregates[level_n_lookup].contains_aggregate:
            return aggregates[level_n_lookup], lookup_parts[n:]
    return False, () 

# 需要导入模块: from django.db.models.constants import LOOKUP_SEP [as 别名]
# 或者: from django.db.models.constants.LOOKUP_SEP import join [as 别名]
def refs_expression(lookup_parts, annotations):
    """
    A helper method to check if the lookup_parts contains references
    to the given annotations set. Because the LOOKUP_SEP is contained in the
    default annotation names we must check each prefix of the lookup_parts
    for a match.
    """
    for n in range(len(lookup_parts) + 1):
        level_n_lookup = LOOKUP_SEP.join(lookup_parts[0:n])
        if level_n_lookup in annotations and annotations[level_n_lookup]:
            return annotations[level_n_lookup], lookup_parts[n:]
    return False, () 

# 需要导入模块: from django.db.models.constants import LOOKUP_SEP [as 别名]
# 或者: from django.db.models.constants.LOOKUP_SEP import join [as 别名]
def rewrite_cols(self, annotation, col_cnt):
        # We must make sure the inner query has the referred columns in it.
        # If we are aggregating over an annotation, then Django uses Ref()
        # instances to note this. However, if we are annotating over a column
        # of a related model, then it might be that column isn't part of the
        # SELECT clause of the inner query, and we must manually make sure
        # the column is selected. An example case is:
        #    .aggregate(Sum('author__awards'))
        # Resolving this expression results in a join to author, but there
        # is no guarantee the awards column of author is in the select clause
        # of the query. Thus we must manually add the column to the inner
        # query.
        orig_exprs = annotation.get_source_expressions()
        new_exprs = []
        for expr in orig_exprs:
            if isinstance(expr, Ref):
                # Its already a Ref to subquery (see resolve_ref() for
                # details)
                new_exprs.append(expr)
            elif isinstance(expr, Col):
                # Reference to column. Make sure the referenced column
                # is selected.
                col_cnt += 1
                col_alias = '__col%d' % col_cnt
                self.annotations[col_alias] = expr
                self.append_annotation_mask([col_alias])
                new_exprs.append(Ref(col_alias, expr))
            else:
                # Some other expression not referencing database values
                # directly. Its subexpression might contain Cols.
                new_expr, col_cnt = self.rewrite_cols(expr, col_cnt)
                new_exprs.append(new_expr)
        annotation.set_source_expressions(new_exprs)
        return annotation, col_cnt