Description of ASMCircuitBreaker fields - Alibaba Cloud Service Mesh

Service Mesh (ASM) allows you to declaratively define the circuit breaking configurations by using the ASMCircuitBreaker CustomResourceDefinition (CRD). This topic describes the fields of ASMCircuitBreaker.

apiVersion

If the version of your ASM instance is 1.15.3.105 or later, you can set the apiVersion field to istio.alibabacloud.com/v1. If you have set the apiVersion field to istio.alibabacloud.com/v1beta1 when you configured ASMCircuitBreaker in the ACK cluster, change the value to istio.alibabacloud.com/v1 in the ASMCircuitBreaker CRD, and deploy the cluster again.
If the version of your ASM instance is earlier than 1.15.3.105, you can set the apiVersion field to istio.alibabacloud.com/v1beta1.

spec

The following tables describe the fields of the ASMCircuitBreaker spec. For more information about the features and examples of ASMCircuitBreaker, see Use the route-level circuit breaking feature of ASM.

ASMCircuitBreakerSpec

Field	Type	Required	Description
workloadSelector	map<string, string>	Yes	The one or more labels that specify a set of pods or VMs on which the circuit breaking rule takes effect. The scope of label search is restricted to the configuration namespace in which the resources reside. For more information, see Workload Selector.
isGateway	bool	No	Specifies whether to apply the configurations to a gateway. The value true indicates that the configurations apply to the gateway. Default value: false.
configs	CircuitBreakerConfig[]	Yes	The circuit breaking rule. You can configure multiple circuit breaking rules.

CircuitBreakerConfig

Field	Type	Required	Description
name	string	No	The name of the circuit breaking rule.
match	CircuitBreakerMatch	No	The match criteria.
breaker_config	BreakerConfig	No	The configurations of route-level circuit breaking.

CircuitBreakerMatch

Field	Type	Required	Description
vhost	VirtualHostMatch	No	The matched virtual host.

BreakerConfig

Field	Type	Required	Description
window_size	Duration	No	The statistical time window. Unit: seconds. Default value: 10. The value cannot exceed 12.
break_duration	Duration	No	The circuit breaking period during which new requests are denied. Unit: seconds. Default value: 30.
slow_request_rt	Duration	No	The response latency of a request beyond which the request is considered a slow request.
average_request_rt	Duration	Yes when the version of the ASM instance is earlier than 1.14 No when the version of the ASM instance is 1.14 or later	The average response time of a service request. Example: 0.01s.
max_slow_requests	uint32	No	The maximum number of slow requests that are allowed. The value must be an integer. Example: 1000. If this limit is reached, new requests are denied.
error_percent	Percent	No	The maximum percentage of error requests that are allowed. The error code of an error request is 5XX. If this limit is reached within the statistical time window, new requests are denied.
min_request_amount	uint32	No	The minimum number of requests. Default value: 0. If you set the error_percent field, we recommend that you also set this field to prevent requests from being denied by mistake.
custom_response	CustomResponse	No	The content that is displayed when a request is denied. You can customize the content.

CustomResponse

Field	Type	Required	Description
status_code	int32	No	The HTTP response status code.
header_to_add	map[string]string	No	The response headers. You can customize the response headers.
body	string	No	The response body. You can customize the response body.

VirtualHostMatch

Field	Type	Required	Description
name	string	No	The name of the matched virtual host.
port	int	No	The matched request port.
route	RouteMatch	Yes	The name of the route corresponding to the matched request port.

RouteMatch

Field	Type	Required	Description
name_match	string	Yes, when you configure a gateway No, when you configure a sidecar proxy	The name of the matched route. This field specifies a single route in a virtual service.
header_match	HeaderMatcher[]	No	The header of the matched service requests. You can configure multiple headers. Important This field is available only when the version of your ASM instance is 1.16 or later and the gateways and sidecar proxies are of the latest versions. For more information about how to upgrade ASM instances and gateways, see Update an ASM instance. For more information about how to upgrade sidecar proxies, see Upgrade sidecar proxies.

HeaderMatcher

Field		Type	Required	Description
name		string	No	The name of the header.
Specify one of the fields based on the match mode	regex_match	string	No	The regular expression used to perform a header match. The header value must match the specified regular expression.
	exact_match	string	No	The value used to perform a header match. The header value must exactly match the specified value.
	prefix_match	string	No	The prefix used to perform a header match. The header value must start with the specified characters.
	suffix_match	string	No	The suffix used to perform a header match. The header value must end with the specified characters.
	present_match	bool	No	If you set this parameter to true, the header match is performed based on whether the header is in the request. The header with the specified name must exist in the request. If you set this parameter to false, the header match is performed based on whether the header is absent. The header with the specified name cannot exist in the request.
invert_match		bool	No	Specifies whether to invert the match result. Default value: false. If you set this parameter to true, the match result will be inverted. For example, a request that does not meet the specified match criteria is considered a matched request. If you set this parameter to false, a request that meets the specified match criteria is considered a matched request.