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fix: add bounds validation and ApplyWithVersion to OT engine
+39
-1
+39
-1
internal/collaboration/ot.go
+39
-1
internal/collaboration/ot.go
···
19
19
From int `json:"from"`
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To int `json:"to"`
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Insert string `json:"insert"`
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+
// Author is set by the client and used for logging/debugging purposes
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+
// to identify which user performed an operation
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Author string `json:"author"`
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}
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···
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ot.mu.Lock()
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defer ot.mu.Unlock()
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30
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+
if op.From < 0 {
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+
op.From = 0
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+
}
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+
if op.To < 0 {
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+
op.To = 0
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+
}
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+
if op.From > len(ot.documentText) {
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+
op.From = len(ot.documentText)
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+
}
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40
if op.To > len(ot.documentText) {
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op.To = len(ot.documentText)
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}
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+
if op.From > op.To {
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+
return ot.documentText
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+
}
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+
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+
newText := ot.documentText[:op.From] + op.Insert + ot.documentText[op.To:]
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+
ot.documentText = newText
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+
ot.version++
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+
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+
return ot.documentText
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+
}
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+
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+
func (ot *OTEngine) ApplyWithVersion(op Operation) (string, int) {
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+
ot.mu.Lock()
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+
defer ot.mu.Unlock()
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+
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+
if op.From < 0 {
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+
op.From = 0
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+
}
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+
if op.To < 0 {
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+
op.To = 0
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+
}
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if op.From > len(ot.documentText) {
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op.From = len(ot.documentText)
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}
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+
if op.To > len(ot.documentText) {
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+
op.To = len(ot.documentText)
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+
}
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+
if op.From > op.To {
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+
return ot.documentText, ot.version
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+
}
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newText := ot.documentText[:op.From] + op.Insert + ot.documentText[op.To:]
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ot.documentText = newText
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ot.version++
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40
-
return ot.documentText
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+
return ot.documentText, ot.version
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79
}
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80
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81
func (ot *OTEngine) GetText() string {