#[non_exhaustive]
pub enum MfaMode {
    Off,
    On,
    Optional,
    Unknown(UnknownVariantValue),
}
Expand description

When writing a match expression against MfaMode, 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 mfamode = unimplemented!();
match mfamode {
    MfaMode::Off => { /* ... */ },
    MfaMode::On => { /* ... */ },
    MfaMode::Optional => { /* ... */ },
    other @ _ if other.as_str() == "NewFeature" => { /* handles a case for `NewFeature` */ },
    _ => { /* ... */ },
}

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

This enum is marked as 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.
§

Off

§

On

§

Optional

§

Unknown(UnknownVariantValue)

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

Implementations§

Returns the &str value of the enum member.

Examples found in repository?
src/model.rs (line 2363)
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    fn as_ref(&self) -> &str {
        self.as_str()
    }
More examples
Hide additional examples
src/json_ser.rs (line 815)
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pub fn serialize_structure_crate_model_create_backend_auth_mfa_config(
    object: &mut aws_smithy_json::serialize::JsonObjectWriter,
    input: &crate::model::CreateBackendAuthMfaConfig,
) -> Result<(), aws_smithy_http::operation::error::SerializationError> {
    if let Some(var_141) = &input.mfa_mode {
        object.key("MFAMode").string(var_141.as_str());
    }
    if let Some(var_142) = &input.settings {
        #[allow(unused_mut)]
        let mut object_143 = object.key("settings").start_object();
        crate::json_ser::serialize_structure_crate_model_settings(&mut object_143, var_142)?;
        object_143.finish();
    }
    Ok(())
}

pub fn serialize_structure_crate_model_create_backend_auth_o_auth_config(
    object: &mut aws_smithy_json::serialize::JsonObjectWriter,
    input: &crate::model::CreateBackendAuthOAuthConfig,
) -> Result<(), aws_smithy_http::operation::error::SerializationError> {
    if let Some(var_144) = &input.domain_prefix {
        object.key("domainPrefix").string(var_144.as_str());
    }
    if let Some(var_145) = &input.o_auth_grant_type {
        object.key("oAuthGrantType").string(var_145.as_str());
    }
    if let Some(var_146) = &input.o_auth_scopes {
        let mut array_147 = object.key("oAuthScopes").start_array();
        for item_148 in var_146 {
            {
                array_147.value().string(item_148.as_str());
            }
        }
        array_147.finish();
    }
    if let Some(var_149) = &input.redirect_sign_in_ur_is {
        let mut array_150 = object.key("redirectSignInURIs").start_array();
        for item_151 in var_149 {
            {
                array_150.value().string(item_151.as_str());
            }
        }
        array_150.finish();
    }
    if let Some(var_152) = &input.redirect_sign_out_ur_is {
        let mut array_153 = object.key("redirectSignOutURIs").start_array();
        for item_154 in var_152 {
            {
                array_153.value().string(item_154.as_str());
            }
        }
        array_153.finish();
    }
    if let Some(var_155) = &input.social_provider_settings {
        #[allow(unused_mut)]
        let mut object_156 = object.key("socialProviderSettings").start_object();
        crate::json_ser::serialize_structure_crate_model_social_provider_settings(
            &mut object_156,
            var_155,
        )?;
        object_156.finish();
    }
    Ok(())
}

pub fn serialize_structure_crate_model_create_backend_auth_password_policy_config(
    object: &mut aws_smithy_json::serialize::JsonObjectWriter,
    input: &crate::model::CreateBackendAuthPasswordPolicyConfig,
) -> Result<(), aws_smithy_http::operation::error::SerializationError> {
    if let Some(var_157) = &input.additional_constraints {
        let mut array_158 = object.key("additionalConstraints").start_array();
        for item_159 in var_157 {
            {
                array_158.value().string(item_159.as_str());
            }
        }
        array_158.finish();
    }
    {
        object.key("minimumLength").number(
            #[allow(clippy::useless_conversion)]
            aws_smithy_types::Number::Float((input.minimum_length).into()),
        );
    }
    Ok(())
}

pub fn serialize_structure_crate_model_create_backend_auth_verification_message_config(
    object: &mut aws_smithy_json::serialize::JsonObjectWriter,
    input: &crate::model::CreateBackendAuthVerificationMessageConfig,
) -> Result<(), aws_smithy_http::operation::error::SerializationError> {
    if let Some(var_160) = &input.delivery_method {
        object.key("deliveryMethod").string(var_160.as_str());
    }
    if let Some(var_161) = &input.email_settings {
        #[allow(unused_mut)]
        let mut object_162 = object.key("emailSettings").start_object();
        crate::json_ser::serialize_structure_crate_model_email_settings(&mut object_162, var_161)?;
        object_162.finish();
    }
    if let Some(var_163) = &input.sms_settings {
        #[allow(unused_mut)]
        let mut object_164 = object.key("smsSettings").start_object();
        crate::json_ser::serialize_structure_crate_model_sms_settings(&mut object_164, var_163)?;
        object_164.finish();
    }
    Ok(())
}

pub fn serialize_structure_crate_model_update_backend_auth_forgot_password_config(
    object: &mut aws_smithy_json::serialize::JsonObjectWriter,
    input: &crate::model::UpdateBackendAuthForgotPasswordConfig,
) -> Result<(), aws_smithy_http::operation::error::SerializationError> {
    if let Some(var_165) = &input.delivery_method {
        object.key("deliveryMethod").string(var_165.as_str());
    }
    if let Some(var_166) = &input.email_settings {
        #[allow(unused_mut)]
        let mut object_167 = object.key("emailSettings").start_object();
        crate::json_ser::serialize_structure_crate_model_email_settings(&mut object_167, var_166)?;
        object_167.finish();
    }
    if let Some(var_168) = &input.sms_settings {
        #[allow(unused_mut)]
        let mut object_169 = object.key("smsSettings").start_object();
        crate::json_ser::serialize_structure_crate_model_sms_settings(&mut object_169, var_168)?;
        object_169.finish();
    }
    Ok(())
}

pub fn serialize_structure_crate_model_update_backend_auth_mfa_config(
    object: &mut aws_smithy_json::serialize::JsonObjectWriter,
    input: &crate::model::UpdateBackendAuthMfaConfig,
) -> Result<(), aws_smithy_http::operation::error::SerializationError> {
    if let Some(var_170) = &input.mfa_mode {
        object.key("MFAMode").string(var_170.as_str());
    }
    if let Some(var_171) = &input.settings {
        #[allow(unused_mut)]
        let mut object_172 = object.key("settings").start_object();
        crate::json_ser::serialize_structure_crate_model_settings(&mut object_172, var_171)?;
        object_172.finish();
    }
    Ok(())
}

Returns all the &str values of the enum members.

Trait Implementations§

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