abe3e0c6da
This change removes a code pattern that I noticed while on a late night audit of cosmovisor in which strings.Builder.WriteString(fmt.Sprintf(...)) calls were being made, yet that's counterproductive to using fmt.Fprintf which will check whether the writer implements .WriteString and then avoids the need to firstly build a string using fmt.Sprintf. The performance wins from this change transcend all dimensions as exhibited below: ```shell $ benchstat before.txt after.txt name old time/op new time/op delta DetailString-8 5.48µs ±23% 4.40µs ±11% -19.79% (p=0.000 n=20+17) name old alloc/op new alloc/op delta DetailString-8 2.63kB ± 0% 2.11kB ± 0% -19.76% (p=0.000 n=20+20) name old allocs/op new allocs/op delta DetailString-8 63.0 ± 0% 50.0 ± 0% -20.63% (p=0.000 n=20+20) ``` Fixes #13229 |
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|---|---|---|
| .. | ||
| client | ||
| keeper | ||
| simulation | ||
| testutil | ||
| types | ||
| README.md | ||
| doc.go | ||
| module.go | ||
| proposal_handler.go | ||
| proposal_handler_test.go | ||
README.md
x/params (Deprecated)
Note: The Params module has been depreacted in favour of each module housing its own parameters.
Abstract
Package params provides a globally available parameter store.
There are two main types, Keeper and Subspace. Subspace is an isolated namespace for a paramstore, where keys are prefixed by preconfigured spacename. Keeper has a permission to access all existing spaces.
Subspace can be used by the individual keepers, which need a private parameter store
that the other keepers cannot modify. The params Keeper can be used to add a route to x/gov router in order to modify any parameter in case a proposal passes.
The following contents explains how to use params module for master and user modules.
Contents
Keeper
In the app initialization stage, subspaces can be allocated for other modules' keeper using Keeper.Subspace and are stored in Keeper.spaces. Then, those modules can have a reference to their specific parameter store through Keeper.GetSubspace.
Example:
type ExampleKeeper struct {
paramSpace paramtypes.Subspace
}
func (k ExampleKeeper) SetParams(ctx sdk.Context, params types.Params) {
k.paramSpace.SetParamSet(ctx, ¶ms)
}
Subspace
Subspace is a prefixed subspace of the parameter store. Each module which uses the
parameter store will take a Subspace to isolate permission to access.
Key
Parameter keys are human readable alphanumeric strings. A parameter for the key
"ExampleParameter" is stored under []byte("SubspaceName" + "/" + "ExampleParameter"),
where "SubspaceName" is the name of the subspace.
Subkeys are secondary parameter keys those are used along with a primary parameter key. Subkeys can be used for grouping or dynamic parameter key generation during runtime.
KeyTable
All of the parameter keys that will be used should be registered at the compile
time. KeyTable is essentially a map[string]attribute, where the string is a parameter key.
Currently, attribute consists of a reflect.Type, which indicates the parameter
type to check that provided key and value are compatible and registered, as well as a function ValueValidatorFn to validate values.
Only primary keys have to be registered on the KeyTable. Subkeys inherit the
attribute of the primary key.
ParamSet
Modules often define parameters as a proto message. The generated struct can implement
ParamSet interface to be used with the following methods:
KeyTable.RegisterParamSet(): registers all parameters in the structSubspace.{Get, Set}ParamSet(): Get to & Set from the struct
The implementor should be a pointer in order to use GetParamSet().