49 lines
1 KiB
Go
49 lines
1 KiB
Go
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// Copyright © 2016 Abcum Ltd
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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 db
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import (
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"context"
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)
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func vers(ctx context.Context) int {
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v := ctx.Value(ctxKeyDive)
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switch v {
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case nil:
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return 0
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default:
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return v.(int)
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}
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}
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func dive(ctx context.Context) context.Context {
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v := ctx.Value(ctxKeyDive)
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switch v {
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case nil:
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return context.WithValue(ctx, ctxKeyDive, 1)
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default:
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if v.(int) > maxRecursiveQueries {
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panic(errRecursiveOverload)
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}
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return context.WithValue(ctx, ctxKeyDive, v.(int)+1)
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}
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}
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