def Print(self, resources, single=False, intermediate=False):
"""Prints resources using printer.AddRecord() and printer.Finish().
Args:
resources: A singleton or list of JSON-serializable Python objects.
single: If True then resources is a single item and not a list.
For example, use this to print a single object as JSON.
intermediate: This is an intermediate call, do not call Finish().
Raises:
ProjectionRequiredError: If the projection is empty and the format
requires a non-empty projection.
"""
if 'disable' in self.attributes:
# Disable formatted output and do not consume the resources.
self._empty = False
return
if self._non_empty_projection_required and (
not self.column_attributes or not self.column_attributes.Columns()):
raise ProjectionRequiredError(
'Format [{0}] requires a non-empty projection.'.format(self._name))
# Resources may be a generator and since generators can raise exceptions, we
# have to call Finish() in the finally block to make sure that the resources
# we've been able to pull out of the generator are printed before control is
# given to the exception-handling code.
try:
if resources:
if single or not resource_property.IsListLike(resources):
self.AddRecord(resources, delimit=intermediate)
else:
for resource in resources:
self.AddRecord(resource)
finally:
if not intermediate:
self.Finish()
def TransformFilter(r, expression):
"""Selects elements of r that match the filter expression.
Args:
r: A JSON-serializable object.
expression: The filter expression to apply to r.
Returns:
The elements of r that match the filter expression.
Example:
x.filter("key:val") selects elements of r that have 'key' fields containing
'val'.
"""
# import loop
from googlecloudsdk.core.resource import resource_filter # pylint: disable=g-import-not-at-top
if not r:
return r
select = resource_filter.Compile(expression).Evaluate
if not resource_property.IsListLike(r):
return r if select(r) else ''
transformed = []
for item in r:
if select(item):
transformed.append(item)
return transformed
def Run(self, args):
if args.json_file:
with open(args.json_file, 'r') as f:
resources = json.load(f)
else:
resources = json.load(sys.stdin)
# TODO(gsfowler): Drop this if when the --aggregate global flag lands.
if args.aggregate:
key = resource_lex.Lexer(args.aggregate).Key()
resources = Aggregator(resources, key)
# TODO(gsfowler): Return resources here when the --filter global flag lands.
if not args.format:
args.format = 'json'
if not args.filter:
return resources
select = resource_filter.Compile(args.filter).Evaluate
filtered_resources = []
if resource_property.IsListLike(resources):
for resource in resources:
if select(resource):
filtered_resources.append(resource)
elif select(resources):
# treat non-iterable resources as a list of length 1
filtered_resources.append(resources)
return filtered_resources
def _AddSortByTap(self):
"""Sorts the resources using the --sort-by keys."""
if not resource_property.IsListLike(self._resources):
return
sort_keys = self._GetSortKeys()
if not sort_keys:
return
self._args.sort_by = None
# This loop partitions the keys into groups having the same reverse value.
# The groups are then applied in reverse order to maintain the original
# precedence.
#
# This is not a pure tap since, by necessity, it consumes self._resources
# to sort and converts it to a list.
groups = [
] # [(group_keys, group_reverse)] LIFO to preserve precedence
group_keys = [] # keys for current group
group_reverse = False
for key, reverse in sort_keys:
if not group_keys:
group_reverse = reverse
elif group_reverse != reverse:
groups.insert(0, (group_keys, group_reverse))
group_keys = []
group_reverse = reverse
group_keys.append(key)
if group_keys:
groups.insert(0, (group_keys, group_reverse))
# Finally sort the resources by groups having the same reverse value.
for keys, reverse in groups:
self._SortResources(keys, reverse)
def Evaluate(self, obj):
"""Apply the list of transforms to obj and return the transformed value."""
for transform in self._transforms:
if transform.map_transform and resource_property.IsListLike(obj):
# A transform mapped on a list - transform each list item.
# map_transform > 1 for nested lists. For example:
# abc[].def[].ghi[].map(3)
# iterates over the items in ghi[] for all abc[] and def[].
items = obj
for _ in range(transform.map_transform - 1):
nested = []
try:
# Stop if items is not a list.
for item in items:
nested.extend(item)
except TypeError:
break
items = nested
obj = []
for item in items:
obj.append(
transform.func(item, *transform.args,
**transform.kwargs))
elif obj or not transform.map_transform:
obj = transform.func(obj, *transform.args, **transform.kwargs)
return obj
def _ProjectTransform(self, obj, transforms):
"""Applies transforms to obj.
Args:
obj: The object to transform.
transforms: The list of resource_projection_parser._Transform objects.
Returns:
The transformed object.
"""
if not self._transforms_enabled:
if self._transforms_enabled is not None:
return obj
if transforms[0].active not in (None, self._projection.active):
return obj
for transform in transforms:
if transform.map_transform and resource_property.IsListLike(obj):
# A transform mapped on a list - transform each list item.
items = obj
obj = []
for item in items:
obj.append(
transform.func(item, *transform.args,
**transform.kwargs))
elif obj or not transform.map_transform:
obj = transform.func(obj, *transform.args, **transform.kwargs)
return obj
def Print(resources, print_format, out=None, defaults=None, single=False):
"""Prints the given resources.
Args:
resources: A singleton or list of JSON-serializable Python objects.
print_format: The _FORMATTER name with optional projection expression.
out: Output stream, log.out if None.
defaults: Optional resource_projection_spec.ProjectionSpec defaults.
single: If True then resources is a single item and not a list.
For example, use this to print a single object as JSON.
Raises:
ProjectionRequiredError: If a format requires a projection and one is not
provided.
"""
printer = Printer(print_format, out=out, defaults=defaults)
if printer.ByColumns() and not printer.column_attributes.Columns():
raise ProjectionRequiredError(
'Format [{0}] requires a non-empty projection.'.format(
printer.column_attributes.Name()))
# Resources may be a generator and since generators can raise exceptions, we
# have to call Finish() in the finally block to make sure that the resources
# we've been able to pull out of the generator are printed before control is
# given to the exception-handling code.
try:
if resources:
if single or not resource_property.IsListLike(resources):
printer.AddRecord(resources, delimit=False)
else:
for resource in resources:
printer.AddRecord(resource)
finally:
printer.Finish()
def Display(self):
"""The default display method."""
if not log.IsUserOutputEnabled():
log.info('Display disabled.')
# NOTICE: Do not consume resources here. Some commands use this case to
# access the results of Run() via the return value of Execute(). However,
# to satisfy callers who are only interetsted in silent side effects,
# generators/iterators must be converted to a list here.
if resource_property.IsListLike(self._resources):
return list(self._resources)
return self._resources
# Initialize the printer.
self._InitPrinter()
# Add a URI cache update tap if needed.
self._AddUriCacheTap()
# Add a resource page tap if needed.
self._AddPageTap()
# Add a resource flatten tap if needed.
self._AddFlattenTap()
# Add a sort tap if needed.
self._AddSortByTap()
# Add a resource filter tap if needed.
self._AddFilterTap()
# Add a resource limit tap if needed.
self._AddLimitTap()
# Add the URI replace tap if needed.
self._AddUriReplaceTap()
resources_were_displayed = True
if self._printer:
# Most command output will end up here.
log.info('Display format: "%s"', self._format)
self._printer.Print(self._resources)
resources_were_displayed = self._printer.ResourcesWerePrinted()
elif hasattr(self._command, 'Display'):
# This will eventually be rare.
log.info('Explicit Display.')
self._command.Display(self._args, self._resources)
# Resource display is done.
log.out.flush()
# If the default format was used then display the epilog.
if not self._args.IsSpecified('format'):
self._command.Epilog(resources_were_displayed)
return self._resources
def Evaluate(self, obj):
"""Apply the list of transforms to obj and return the transformed value."""
for transform in self._transforms:
if transform.map_transform and resource_property.IsListLike(obj):
# A transform mapped on a list - transform each list item.
items = obj
obj = []
for item in items:
obj.append(transform.func(item, *transform.args, **transform.kwargs))
elif obj or not transform.map_transform:
if transform.restriction:
obj = transform.func(*transform.args, **transform.kwargs)
else:
obj = transform.func(obj, *transform.args, **transform.kwargs)
return obj
def _PrintResources(resources, printer, single=False):
"""Prints resources using printer.AddRecord() and printer.Finish().
Args:
resources: A singleton or list of JSON-serializable Python objects.
printer: An instantiated printer.
single: If True then resources is a single item and not a list.
For example, use this to print a single object as JSON.
"""
# Resources may be a generator and since generators can raise exceptions, we
# have to call Finish() in the finally block to make sure that the resources
# we've been able to pull out of the generator are printed before control is
# given to the exception-handling code.
try:
if resources:
if single or not resource_property.IsListLike(resources):
printer.AddRecord(resources, delimit=False)
else:
for resource in resources:
printer.AddRecord(resource)
finally:
printer.Finish()