49 lines
1.3 KiB
Go
49 lines
1.3 KiB
Go
// Copyright 2019 Dolthub, Inc.
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//
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// Licensed under the Apache License, Version 2.0 (the "License");
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// you may not use this file except in compliance with the License.
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// You may obtain a copy of the License at
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//
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// http://www.apache.org/licenses/LICENSE-2.0
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//
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// Unless required by applicable law or agreed to in writing, software
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// distributed under the License is distributed on an "AS IS" BASIS,
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// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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// See the License for the specific language governing permissions and
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// limitations under the License.
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package events
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import (
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"context"
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"fmt"
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)
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type contextKeyT struct {
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}
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// contextEventKey key used for storing and retrieving an event from the context.
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var contextEventKey = contextKeyT{}
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// NewContextForEvent creates a new context with the event provided
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func NewContextForEvent(ctx context.Context, evt *Event) context.Context {
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return context.WithValue(ctx, contextEventKey, evt)
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}
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// GetEventFromContext retrieves the event from the context if one exists.
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func GetEventFromContext(ctx context.Context) *Event {
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val := ctx.Value(contextEventKey)
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if val == nil {
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return nil
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}
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evt, ok := val.(*Event)
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if !ok {
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panic(fmt.Errorf("value stored in context with key '%s' is not an event", contextEventKey))
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}
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return evt
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}
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