#[non_exhaustive]pub enum ReturnConsumedCapacity {
Indexes,
None,
Total,
Unknown(UnknownVariantValue),
}
Expand description
When writing a match expression against ReturnConsumedCapacity
, it is important to ensure
your code is forward-compatible. That is, if a match arm handles a case for a
feature that is supported by the service but has not been represented as an enum
variant in a current version of SDK, your code should continue to work when you
upgrade SDK to a future version in which the enum does include a variant for that
feature.
Here is an example of how you can make a match expression forward-compatible:
# let returnconsumedcapacity = unimplemented!();
match returnconsumedcapacity {
ReturnConsumedCapacity::Indexes => { /* ... */ },
ReturnConsumedCapacity::None => { /* ... */ },
ReturnConsumedCapacity::Total => { /* ... */ },
other @ _ if other.as_str() == "NewFeature" => { /* handles a case for `NewFeature` */ },
_ => { /* ... */ },
}
The above code demonstrates that when returnconsumedcapacity
represents
NewFeature
, the execution path will lead to the second last match arm,
even though the enum does not contain a variant ReturnConsumedCapacity::NewFeature
in the current version of SDK. The reason is that the variable other
,
created by the @
operator, is bound to
ReturnConsumedCapacity::Unknown(UnknownVariantValue("NewFeature".to_owned()))
and calling as_str
on it yields "NewFeature"
.
This match expression is forward-compatible when executed with a newer
version of SDK where the variant ReturnConsumedCapacity::NewFeature
is defined.
Specifically, when returnconsumedcapacity
represents NewFeature
,
the execution path will hit the second last match arm as before by virtue of
calling as_str
on ReturnConsumedCapacity::NewFeature
also yielding "NewFeature"
.
Explicitly matching on the Unknown
variant should
be avoided for two reasons:
- The inner data
UnknownVariantValue
is opaque, and no further information can be extracted. - It might inadvertently shadow other intended match arms.
Determines the level of detail about either provisioned or on-demand throughput consumption that is returned in the response:
-
INDEXES
- The response includes the aggregateConsumedCapacity
for the operation, together withConsumedCapacity
for each table and secondary index that was accessed.Note that some operations, such as
GetItem
andBatchGetItem
, do not access any indexes at all. In these cases, specifyingINDEXES
will only returnConsumedCapacity
information for table(s). -
TOTAL
- The response includes only the aggregateConsumedCapacity
for the operation. -
NONE
- NoConsumedCapacity
details are included in the response.
Variants (Non-exhaustive)§
This enum is marked as non-exhaustive
Indexes
None
Total
Unknown(UnknownVariantValue)
Unknown
. See the docs on this enum for the correct way to handle unknown variants.Unknown
contains new variants that have been added since this code was generated.
Implementations§
source§impl ReturnConsumedCapacity
impl ReturnConsumedCapacity
sourcepub fn try_parse(value: &str) -> Result<Self, UnknownVariantError>
pub fn try_parse(value: &str) -> Result<Self, UnknownVariantError>
Parses the enum value while disallowing unknown variants.
Unknown variants will result in an error.
Trait Implementations§
source§impl AsRef<str> for ReturnConsumedCapacity
impl AsRef<str> for ReturnConsumedCapacity
source§impl Clone for ReturnConsumedCapacity
impl Clone for ReturnConsumedCapacity
source§fn clone(&self) -> ReturnConsumedCapacity
fn clone(&self) -> ReturnConsumedCapacity
1.0.0 · source§fn clone_from(&mut self, source: &Self)
fn clone_from(&mut self, source: &Self)
source
. Read moresource§impl Debug for ReturnConsumedCapacity
impl Debug for ReturnConsumedCapacity
source§impl From<&str> for ReturnConsumedCapacity
impl From<&str> for ReturnConsumedCapacity
source§impl FromStr for ReturnConsumedCapacity
impl FromStr for ReturnConsumedCapacity
source§impl Hash for ReturnConsumedCapacity
impl Hash for ReturnConsumedCapacity
source§impl Ord for ReturnConsumedCapacity
impl Ord for ReturnConsumedCapacity
source§fn cmp(&self, other: &ReturnConsumedCapacity) -> Ordering
fn cmp(&self, other: &ReturnConsumedCapacity) -> Ordering
1.21.0 · source§fn max(self, other: Self) -> Selfwhere
Self: Sized,
fn max(self, other: Self) -> Selfwhere Self: Sized,
source§impl PartialEq for ReturnConsumedCapacity
impl PartialEq for ReturnConsumedCapacity
source§fn eq(&self, other: &ReturnConsumedCapacity) -> bool
fn eq(&self, other: &ReturnConsumedCapacity) -> bool
self
and other
values to be equal, and is used
by ==
.source§impl PartialOrd for ReturnConsumedCapacity
impl PartialOrd for ReturnConsumedCapacity
source§fn partial_cmp(&self, other: &ReturnConsumedCapacity) -> Option<Ordering>
fn partial_cmp(&self, other: &ReturnConsumedCapacity) -> Option<Ordering>
1.0.0 · source§fn le(&self, other: &Rhs) -> bool
fn le(&self, other: &Rhs) -> bool
self
and other
) and is used by the <=
operator. Read moreimpl Eq for ReturnConsumedCapacity
impl StructuralEq for ReturnConsumedCapacity
impl StructuralPartialEq for ReturnConsumedCapacity
Auto Trait Implementations§
impl RefUnwindSafe for ReturnConsumedCapacity
impl Send for ReturnConsumedCapacity
impl Sync for ReturnConsumedCapacity
impl Unpin for ReturnConsumedCapacity
impl UnwindSafe for ReturnConsumedCapacity
Blanket Implementations§
source§impl<T> BorrowMut<T> for Twhere
T: ?Sized,
impl<T> BorrowMut<T> for Twhere T: ?Sized,
source§fn borrow_mut(&mut self) -> &mut T
fn borrow_mut(&mut self) -> &mut T
§impl<Q, K> Equivalent<K> for Qwhere
Q: Eq + ?Sized,
K: Borrow<Q> + ?Sized,
impl<Q, K> Equivalent<K> for Qwhere Q: Eq + ?Sized, K: Borrow<Q> + ?Sized,
§fn equivalent(&self, key: &K) -> bool
fn equivalent(&self, key: &K) -> bool
§impl<Q, K> Equivalent<K> for Qwhere
Q: Eq + ?Sized,
K: Borrow<Q> + ?Sized,
impl<Q, K> Equivalent<K> for Qwhere Q: Eq + ?Sized, K: Borrow<Q> + ?Sized,
§fn equivalent(&self, key: &K) -> bool
fn equivalent(&self, key: &K) -> bool
key
and return true
if they are equal.