Files
tidb/pkg/expression/contextopt/sessionvars.go

58 lines
2.1 KiB
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// Copyright 2024 PingCAP, Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package contextopt
import (
"github.com/pingcap/tidb/pkg/expression/context"
"github.com/pingcap/tidb/pkg/sessionctx/variable"
"github.com/pingcap/tidb/pkg/util/intest"
)
var _ context.OptionalEvalPropProvider = &SessionVarsPropProvider{}
var _ RequireOptionalEvalProps = SessionVarsPropReader{}
// SessionVarsPropProvider is a provider to get the session variables
type SessionVarsPropProvider struct {
variable.SessionVarsProvider
}
// NewSessionVarsProvider returns a new SessionVarsPropProvider
func NewSessionVarsProvider(provider variable.SessionVarsProvider) *SessionVarsPropProvider {
intest.AssertNotNil(provider)
return &SessionVarsPropProvider{provider}
}
// Desc implements the OptionalEvalPropProvider interface.
func (p *SessionVarsPropProvider) Desc() *context.OptionalEvalPropDesc {
return context.OptPropSessionVars.Desc()
}
// SessionVarsPropReader is used by expression to read property context.OptPropSessionVars
type SessionVarsPropReader struct{}
// RequiredOptionalEvalProps implements the RequireOptionalEvalProps interface.
func (SessionVarsPropReader) RequiredOptionalEvalProps() context.OptionalEvalPropKeySet {
return context.OptPropSessionVars.AsPropKeySet()
}
// GetSessionVars returns the session vars from the context
func (SessionVarsPropReader) GetSessionVars(ctx context.EvalContext) (*variable.SessionVars, error) {
p, err := getPropProvider[*SessionVarsPropProvider](ctx, context.OptPropSessionVars)
if err != nil {
return nil, err
}
return p.GetSessionVars(), nil
}