Enum aws_sdk_lambda::model::EventSourcePosition

#[non_exhaustive]
pub enum EventSourcePosition {
    AtTimestamp,
    Latest,
    TrimHorizon,
    Unknown(UnknownVariantValue),
}

When writing a match expression against EventSourcePosition, 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 eventsourceposition = unimplemented!();
match eventsourceposition {
    EventSourcePosition::AtTimestamp => { /* ... */ },
    EventSourcePosition::Latest => { /* ... */ },
    EventSourcePosition::TrimHorizon => { /* ... */ },
    other @ _ if other.as_str() == "NewFeature" => { /* handles a case for `NewFeature` */ },
    _ => { /* ... */ },
}

The above code demonstrates that when eventsourceposition represents NewFeature, the execution path will lead to the second last match arm, even though the enum does not contain a variant EventSourcePosition::NewFeature in the current version of SDK. The reason is that the variable other, created by the @ operator, is bound to EventSourcePosition::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 EventSourcePosition::NewFeature is defined. Specifically, when eventsourceposition represents NewFeature, the execution path will hit the second last match arm as before by virtue of calling as_str on EventSourcePosition::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.

Variants (Non-exhaustive)

Non-exhaustive enums could have additional variants added in future. Therefore, when matching against variants of non-exhaustive enums, an extra wildcard arm must be added to account for any future variants.

AtTimestamp

Latest

TrimHorizon

Unknown(UnknownVariantValue)

Unknown contains new variants that have been added since this code was generated.

Implementations

impl EventSourcePosition

pub fn as_str(&self) -> &str

Returns the &str value of the enum member.

Examples found in repository

src/model.rs (line 3475)

    fn as_ref(&self) -> &str {
        self.as_str()
    }

src/json_ser.rs (line 234)

pub fn serialize_structure_crate_input_create_event_source_mapping_input(
    object: &mut aws_smithy_json::serialize::JsonObjectWriter,
    input: &crate::input::CreateEventSourceMappingInput,
) -> Result<(), aws_smithy_http::operation::error::SerializationError> {
    if let Some(var_24) = &input.amazon_managed_kafka_event_source_config {
        #[allow(unused_mut)]
        let mut object_25 = object
            .key("AmazonManagedKafkaEventSourceConfig")
            .start_object();
        crate::json_ser::serialize_structure_crate_model_amazon_managed_kafka_event_source_config(
            &mut object_25,
            var_24,
        )?;
        object_25.finish();
    }
    if let Some(var_26) = &input.batch_size {
        object.key("BatchSize").number(
            #[allow(clippy::useless_conversion)]
            aws_smithy_types::Number::NegInt((*var_26).into()),
        );
    }
    if let Some(var_27) = &input.bisect_batch_on_function_error {
        object.key("BisectBatchOnFunctionError").boolean(*var_27);
    }
    if let Some(var_28) = &input.destination_config {
        #[allow(unused_mut)]
        let mut object_29 = object.key("DestinationConfig").start_object();
        crate::json_ser::serialize_structure_crate_model_destination_config(
            &mut object_29,
            var_28,
        )?;
        object_29.finish();
    }
    if let Some(var_30) = &input.enabled {
        object.key("Enabled").boolean(*var_30);
    }
    if let Some(var_31) = &input.event_source_arn {
        object.key("EventSourceArn").string(var_31.as_str());
    }
    if let Some(var_32) = &input.filter_criteria {
        #[allow(unused_mut)]
        let mut object_33 = object.key("FilterCriteria").start_object();
        crate::json_ser::serialize_structure_crate_model_filter_criteria(&mut object_33, var_32)?;
        object_33.finish();
    }
    if let Some(var_34) = &input.function_name {
        object.key("FunctionName").string(var_34.as_str());
    }
    if let Some(var_35) = &input.function_response_types {
        let mut array_36 = object.key("FunctionResponseTypes").start_array();
        for item_37 in var_35 {
            {
                array_36.value().string(item_37.as_str());
            }
        }
        array_36.finish();
    }
    if let Some(var_38) = &input.maximum_batching_window_in_seconds {
        object.key("MaximumBatchingWindowInSeconds").number(
            #[allow(clippy::useless_conversion)]
            aws_smithy_types::Number::NegInt((*var_38).into()),
        );
    }
    if let Some(var_39) = &input.maximum_record_age_in_seconds {
        object.key("MaximumRecordAgeInSeconds").number(
            #[allow(clippy::useless_conversion)]
            aws_smithy_types::Number::NegInt((*var_39).into()),
        );
    }
    if let Some(var_40) = &input.maximum_retry_attempts {
        object.key("MaximumRetryAttempts").number(
            #[allow(clippy::useless_conversion)]
            aws_smithy_types::Number::NegInt((*var_40).into()),
        );
    }
    if let Some(var_41) = &input.parallelization_factor {
        object.key("ParallelizationFactor").number(
            #[allow(clippy::useless_conversion)]
            aws_smithy_types::Number::NegInt((*var_41).into()),
        );
    }
    if let Some(var_42) = &input.queues {
        let mut array_43 = object.key("Queues").start_array();
        for item_44 in var_42 {
            {
                array_43.value().string(item_44.as_str());
            }
        }
        array_43.finish();
    }
    if let Some(var_45) = &input.self_managed_event_source {
        #[allow(unused_mut)]
        let mut object_46 = object.key("SelfManagedEventSource").start_object();
        crate::json_ser::serialize_structure_crate_model_self_managed_event_source(
            &mut object_46,
            var_45,
        )?;
        object_46.finish();
    }
    if let Some(var_47) = &input.self_managed_kafka_event_source_config {
        #[allow(unused_mut)]
        let mut object_48 = object
            .key("SelfManagedKafkaEventSourceConfig")
            .start_object();
        crate::json_ser::serialize_structure_crate_model_self_managed_kafka_event_source_config(
            &mut object_48,
            var_47,
        )?;
        object_48.finish();
    }
    if let Some(var_49) = &input.source_access_configurations {
        let mut array_50 = object.key("SourceAccessConfigurations").start_array();
        for item_51 in var_49 {
            {
                #[allow(unused_mut)]
                let mut object_52 = array_50.value().start_object();
                crate::json_ser::serialize_structure_crate_model_source_access_configuration(
                    &mut object_52,
                    item_51,
                )?;
                object_52.finish();
            }
        }
        array_50.finish();
    }
    if let Some(var_53) = &input.starting_position {
        object.key("StartingPosition").string(var_53.as_str());
    }
    if let Some(var_54) = &input.starting_position_timestamp {
        object
            .key("StartingPositionTimestamp")
            .date_time(var_54, aws_smithy_types::date_time::Format::EpochSeconds)?;
    }
    if let Some(var_55) = &input.topics {
        let mut array_56 = object.key("Topics").start_array();
        for item_57 in var_55 {
            {
                array_56.value().string(item_57.as_str());
            }
        }
        array_56.finish();
    }
    if let Some(var_58) = &input.tumbling_window_in_seconds {
        object.key("TumblingWindowInSeconds").number(
            #[allow(clippy::useless_conversion)]
            aws_smithy_types::Number::NegInt((*var_58).into()),
        );
    }
    Ok(())
}

pub const fn values() -> &'static [&'static str]

Returns all the &str values of the enum members.

Trait Implementations

impl AsRef<str> for EventSourcePosition

fn as_ref(&self) -> &str

Converts this type into a shared reference of the (usually inferred) input type.

impl Clone for EventSourcePosition

fn clone(&self) -> EventSourcePosition

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for EventSourcePosition

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl From<&str> for EventSourcePosition

fn from(s: &str) -> Self

Converts to this type from the input type.

impl FromStr for EventSourcePosition

type Err = Infallible

The associated error which can be returned from parsing.

fn from_str(s: &str) -> Result<Self, Self::Err>

Parses a string s to return a value of this type.

impl Hash for EventSourcePosition

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)where
    H: Hasher,
    Self: Sized,

Feeds a slice of this type into the given Hasher.

impl Ord for EventSourcePosition

fn cmp(&self, other: &EventSourcePosition) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Selfwhere
    Self: Sized,

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Selfwhere
    Self: Sized,

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Selfwhere
    Self: Sized + PartialOrd<Self>,

Restrict a value to a certain interval.

impl PartialEq<EventSourcePosition> for EventSourcePosition

fn eq(&self, other: &EventSourcePosition) -> bool

This method tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

This method tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl PartialOrd<EventSourcePosition> for EventSourcePosition

fn partial_cmp(&self, other: &EventSourcePosition) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

This method tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

This method tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

This method tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

This method tests greater than or equal to (for self and other) and is used by the >= operator.

impl Eq for EventSourcePosition

impl StructuralEq for EventSourcePosition

impl StructuralPartialEq for EventSourcePosition