[#48] AI 코드 문맥을 debug artifact에서 보호한다

README.md

@@ -154,8 +154,8 @@ artifact에는 다음 파일이 포함됩니다.
 | `branch-pairs.json` | base branch와 감시 대상 branch 전체의 이름순 비교 조합 |
 | `deterministic-evidence.json` | git merge signal, changed files, changed hunks, check/PR metadata, deterministic risk 결과 |
 | `ai-target-selection.json` | AI 호출 대상 branch와 skipped branch 사유 |
-| `ai-prompt.json` | OpenAI에 전달한 system prompt, user prompt, response shape |
-| `ai-response.json` | provider가 반환한 raw response |
+| `ai-prompt.json` | OpenAI 요청 대상 branch, system prompt, response shape, 코드 원문을 제외한 file·line range·길이·hash·잘림 여부 |
+| `ai-response.json` | provider response와 제안 patch 원문을 제외한 byte length·line count·hunk range |
 | `ai-error.json` | provider 호출 또는 response validation 실패 요약. 실패가 없으면 생성되지 않을 수 있음 |
 | `ai-result.json` | response validation 이후 branch별 AI prediction, skipped, failed 매핑 결과 |
 | `report.md` | 최종 Markdown report |

src/debug/aiPredictionArtifact.ts

@@ -0,0 +1,203 @@
+import { createHash } from "node:crypto"
+
+type AiPredictionPromptDebugEventInput = {
+  targetBranches: Array<{
+    branchName: string
+    baseBranch: string
+  }>
+  prompt: {
+    systemPrompt: string
+    userPrompt: string
+    responseShape?: string
+  }
+}
+
+type AiPredictionResponseDebugEventInput = {
+  targetBranches: Array<{
+    branchName: string
+    baseBranch: string
+  }>
+  response: unknown
+}
+
+export type AiPredictionPromptDebugArtifact = {
+  targetBranches: Array<{
+    branchName: string
+    baseBranch: string
+  }>
+  prompt: {
+    systemPrompt: string
+    userPrompt: string
+    responseShape?: string
+  }
+}
+
+export type AiPredictionResponseDebugArtifact = {
+  targetBranches: Array<{
+    branchName: string
+    baseBranch: string
+  }>
+  response: unknown
+}
+
+// OpenAI에 전달된 prompt event에서 consumer repository 코드 원문만 metadata로 치환
+export function sanitizeAiPredictionPromptDebugEvent(
+  event: AiPredictionPromptDebugEventInput
+): AiPredictionPromptDebugArtifact {
+  return {
+    targetBranches: event.targetBranches.map(target => ({
+      branchName: target.branchName,
+      baseBranch: target.baseBranch
+    })),
+    prompt: {
+      systemPrompt: event.prompt.systemPrompt,
+      userPrompt: sanitizedUserPromptFor(event.prompt.userPrompt),
+      ...(event.prompt.responseShape
+        ? { responseShape: event.prompt.responseShape }
+        : {})
+    }
+  }
+}
+
+// provider response에서 제안 patch 원문만 크기와 hunk metadata로 치환
+export function sanitizeAiPredictionResponseDebugEvent(
+  event: AiPredictionResponseDebugEventInput
+): AiPredictionResponseDebugArtifact {
+  return {
+    targetBranches: event.targetBranches.map(target => ({
+      branchName: target.branchName,
+      baseBranch: target.baseBranch
+    })),
+    response: sanitizedResponseValueFor(event.response)
+  }
+}
+
+// JSON prompt는 구조를 유지하고 비정형 prompt는 원문 없이 크기와 hash만 기록
+function sanitizedUserPromptFor(userPrompt: string): string {
+  try {
+    return JSON.stringify(sanitizedJsonValueFor(JSON.parse(userPrompt)), null, 2)
+  } catch {
+    return JSON.stringify(contentMetadataFor(userPrompt, true), null, 2)
+  }
+}
+
+// 중첩된 AI evidence에서 content 문자열을 제거하고 추적용 metadata를 추가
+function sanitizedJsonValueFor(value: unknown): unknown {
+  if (Array.isArray(value)) {
+    return value.map(sanitizedJsonValueFor)
+  }
+
+  if (!isJsonObject(value)) {
+    return value
+  }
+
+  const sanitized = Object.fromEntries(Object.entries(value)
+    .filter(([name, item]) => name !== "content" || typeof item !== "string")
+    .map(([name, item]) => [name, sanitizedJsonValueFor(item)]))
+  const content = typeof value.content === "string" ? value.content : undefined
+
+  if (content === undefined) {
+    return sanitized
+  }
+
+  const startLine = typeof value.startLine === "number" ? value.startLine : undefined
+  const endLine = typeof value.endLine === "number" ? value.endLine : undefined
+
+  return {
+    ...sanitized,
+    ...contentMetadataFor(content),
+    ...(startLine !== undefined && endLine !== undefined
+      ? { lineCount: Math.max(endLine - startLine + 1, 0) }
+      : {})
+  }
+}
+
+// 코드 원문을 재현하지 않고 동일 문맥 여부와 크기만 비교할 metadata 구성
+function contentMetadataFor(content: string, redacted = false): {
+  contentByteLength: number
+  contentHash: string
+  redacted?: true
+} {
+  return {
+    contentByteLength: Buffer.byteLength(content, "utf8"),
+    contentHash: createHash("sha256").update(content, "utf8").digest("hex"),
+    ...(redacted ? { redacted: true as const } : {})
+  }
+}
+
+// 중첩된 provider response에서 patch 문자열만 metadata로 변환
+function sanitizedResponseValueFor(value: unknown): unknown {
+  if (Array.isArray(value)) {
+    return value.map(sanitizedResponseValueFor)
+  }
+
+  if (!isJsonObject(value)) {
+    return value
+  }
+
+  return Object.fromEntries(Object.entries(value).map(([name, item]) => [
+    name,
+    name === "patch" && typeof item === "string"
+      ? patchMetadataFor(item)
+      : sanitizedResponseValueFor(item)
+  ]))
+}
+
+// unified diff 원문을 저장하지 않고 크기와 변경 범위만 추적할 metadata 구성
+function patchMetadataFor(patch: string): {
+  byteLength: number
+  lineCount: number
+  hunkRanges: Array<{
+    oldStart: number
+    oldCount: number
+    newStart: number
+    newCount: number
+  }>
+} {
+  return {
+    byteLength: Buffer.byteLength(patch, "utf8"),
+    lineCount: lineCountFor(patch),
+    hunkRanges: hunkRangesFor(patch)
+  }
+}
+
+// 마지막 줄바꿈은 별도 빈 줄로 세지 않고 patch 줄 수를 계산
+function lineCountFor(value: string): number {
+  if (value.length === 0) {
+    return 0
+  }
+
+  const lines = value.split(/\r\n|\n|\r/)
+  return lines[lines.length - 1] === "" ? lines.length - 1 : lines.length
+}
+
+// unified diff hunk header의 기존/변경 line 범위를 입력 순서대로 추출
+function hunkRangesFor(patch: string): Array<{
+  oldStart: number
+  oldCount: number
+  newStart: number
+  newCount: number
+}> {
+  const ranges: Array<{
+    oldStart: number
+    oldCount: number
+    newStart: number
+    newCount: number
+  }> = []
+  const pattern = /^@@ -(\d+)(?:,(\d+))? \+(\d+)(?:,(\d+))? @@/gm
+
+  for (const match of patch.matchAll(pattern)) {
+    ranges.push({
+      oldStart: Number(match[1]),
+      oldCount: Number(match[2] ?? "1"),
+      newStart: Number(match[3]),
+      newCount: Number(match[4] ?? "1")
+    })
+  }
+
+  return ranges
+}
+
+function isJsonObject(value: unknown): value is Record<string, unknown> {
+  return typeof value === "object" && value !== null
+}

src/workflows/mergeRiskWatch.ts

@@ -19,6 +19,10 @@ import { select as selectAiPredictionTargets } from "../ai/predictionTargetSelec
 import { build as buildMergeRiskReport } from "../reports/reportBuilder.js"
 import { format as formatMergeRiskReportMarkdown } from "../reports/markdownFormatter.js"
 import { send as sendMergeRiskReport } from "../reportChannels/reportChannel.js"
+import {
+  sanitizeAiPredictionPromptDebugEvent,
+  sanitizeAiPredictionResponseDebugEvent
+} from "../debug/aiPredictionArtifact.js"
 import { writerFor as debugArtifactWriterFor } from "../debug/debugArtifact.js"
 import type {
   AiPredictionEvidencePayload
@@ -216,10 +220,16 @@ export async function run(options: MergeRiskWatchOptions): Promise<void> {
     {
       debugObserver: debugArtifactWriter
         ? {
-          // 생성된 AI prompt를 debug artifact로 기록
-          onPromptBuilt: event => debugArtifactWriter.writeJson("ai-prompt.json", event),
-          // 받은 AI response를 debug artifact로 기록
-          onResponseReceived: event => debugArtifactWriter.writeJson("ai-response.json", event),
+          // 생성된 AI prompt에서 코드 원문을 제거한 표현만 debug artifact로 기록
+          onPromptBuilt: event => debugArtifactWriter.writeJson(
+            "ai-prompt.json",
+            sanitizeAiPredictionPromptDebugEvent(event)
+          ),
+          // 받은 AI response에서 제안 patch 원문을 제거한 표현만 debug artifact로 기록
+          onResponseReceived: event => debugArtifactWriter.writeJson(
+            "ai-response.json",
+            sanitizeAiPredictionResponseDebugEvent(event)
+          ),
           // AI prediction 실패 정보를 debug artifact로 기록
           onPredictionFailed: event => debugArtifactWriter.writeJson("ai-error.json", event)
         }