a9s KeyValue SPI Configuration
This document describes a9s KeyValue SPI configuration.
Custom Parameter Configuration
The a9s KeyValue SPI handles custom parameters for all service instances. It does configuration and validation of custom parameters.
The a9s KeyValue SPI defines default values for certain custom parameters. Also, it defines whether a custom parameter can be set by the application developer.
The Platform Operator can overwrite those choices by changing the a9s KeyValue SPI configuration. The Platform Operator
has to configure the property custom_param_config. The property value must be a hash. Every key
in that hash stands for a custom parameter and the value for every key contains the configuration for that particular
parameter.
The configuration for a particular param is a hash consisting of the following optional keys: default_value
and modifiable. The key default_value specifies the default value for that parameter and modifiable specifies
whether the application developer is allowed to set that custom parameter. For example:
service_instance:
custom_param_config:
maxclients:
default_value: 6000
modifiable: false
Default Custom Parameter Configuration
The following table contains custom parameters that are configurable by the Platform Operator. The meaning of those custom parameters can be read in the application developer documentation for a9s KeyValue.
| Name | Default value | Is modifiable | Version Compatibility |
|---|---|---|---|
additional_sentinel_acls | [] | false | all |
additional_valkey_acls | [] | false | all |
cluster-update-node-timeout | 10 | false | all |
down-after-milliseconds | 10000 | true | all |
failover-timeout | 30000 | true | all |
hostname-resolution | 'disabled' | true | all |
lazyfree-lazy-eviction | 'no' | true | all |
lazyfree-lazy-expire | 'no' | true | all |
lua-time-limit | 5000 | true | all |
maxclients | 10000 | true | all |
maxmemory-policy | 'volatile-lru' | true | all |
maxmemory-samples | 5 | true | all |
notify-keyspace-events | '' | true | all |
stop-cluster-update-on-failure | true | false | all |
tls-ciphers | null | true | all |
tls-ciphersuites | null | true | all |
tls-protocols | null | true | all |
additional_sentinel_acls
The parameter additional_sentinel_acls corresponds to the Valkey feature Valkey ACL.
This parameter can be used to modify the ACL rules that are applied by the a9s KeyValue SPI for the Sentinel user.
The ACL rules that are configured using the parameter additional_sentinel_acls will be applied additionally to the ACL
rules that the a9s KeyValue SPI is applying per default.
a9s KeyValue SPI does no validation for the additional_sentinel_acls value except that it must be of type array of
strings or null.
- You need to be careful when setting
modifiabletotrueforadditional_sentinel_aclsas the Application Developer is then able to modify the ACL rules and also to revoke the default ACL rules set by the a9s KeyValue SPI. - Be cautious when setting the ACL rules; configuring them with incorrect or nonexistent values will cause the service key creation to fail.
We recommend to enable to this parameter only for specific plans and not for all service plans. See Per Plan Configuration for more information.
additional_valkey_acls
The parameter additional_valkey_acls corresponds to the Valkey feature Valkey ACL.
This parameter can be used to modify the ACL rules that are applied by the a9s KeyValue SPI for the Valkey user.
The ACL rules that are configured using the parameter additional_valkey_acls will be applied additionally to the ACL
rules that the a9s KeyValue SPI is applying per default.
a9s KeyValue SPI does no validation for the additional_valkey_acls value except that it must be of type array of
strings or null.
- You need to be careful when setting
modifiabletotrueforadditional_valkey_aclsas the Application Developer is then able to modify the ACL rules and also to revoke the default ACL set by the a9s KeyValue SPI. - Be cautious when setting the ACL rules; configuring them with incorrect or nonexistent values will cause the service key creation to fail.
We recommend to enable to this parameter only for specific plans and not for all service plans. See Per Plan Configuration for more information.
tls-protocols
The parameter tls-protocols corresponds to the Valkey configuration parameter tls-protocols.
tls-ciphers
The parameter tls-ciphers corresponds to the Valkey configuration parameter tls-ciphers. This parameter sets the
list of ciphers used for TLS 1.2 and below.
a9s KeyValue SPI does no validation for the tls-ciphers value except that it must be of type string or null
(do not set tls-ciphers in valkey.conf and sentinel.conf).
tls-ciphersuites
The parameter tls-ciphersuites corresponds to the Valkey configuration parameter tls-ciphersuites. This parameter
sets the list of ciphers used for TLS 1.3 and above.
a9s KeyValue SPI does no validation for the tls-ciphersuites value except that it must be of type string or null
(do not set tls-ciphers in valkey.conf and sentinel.conf).
hostname-resolution
For more information, refer to the hostname-resolution section of the Application Developer's documentation.
Example Configuration
Let's build an imaginary example.
The default value for the maxclients custom parameter should be 600. The custom parameter lua-time-limit should
also have a default value of 600 and the application developer should not be allowed to change it.
Then the configuration must look the following way:
custom_param_config:
maxclients:
default_value: 600
modifiable: true
lua-time-limit:
default_value: 600
modifiable: false
failover-timeout:
default_value: 30000
modifiable: true
down-after-milliseconds:
default_value: 10000
modifiable: true
Per Plan Configuration
Take a look at Service Plans documentation if you want to configure custom parameters per plan.
Notes
Additional custom parameters will be made available over time. We do not make all available custom parameters the SPIs know available to the Platform Operator from the beginning.
During the SPI startup, the configuration the Platform Operator made will be checked. When it's invalid, the SPI will not start up.
Protocols
For more details on this property, please refer to the a9s Framework TLS configuration documentation.