refactor: 데모 브랜치 패키지 통일 com.example.medilightv2android → com.medithings.vesiscan

사용자앱 (feature/tab-navigation) 과 패키지 이름 일치. namespace + applicationId 둘 다 com.medithings.vesiscan 로 변경 (기존 데모 앱은 재설치 필요). ## 변경 범위 - Kotlin 148 파일: package + import 문 (714 occurrences) - 디렉토리 이동: com/example/medilightv2android → com/medithings/vesiscan (main, test, androidTest 각각) - app/build.gradle.kts: namespace, applicationId - docs/FLAVOR_DEMO_STABLE.md: 참조 갱신 - V41DetectorCH4Test: BvDispatchResult.methodChosen → method (dto field name fix) ## 주의 - applicationId 가 바뀌므로 기존 데모 앱 (com.example.medilightv2android.demo) 은 Android 관점에서 다른 앱으로 취급 — 재설치 시 PIN/설정 초기화됨. - Fresh install 권장. 기존 앱 (com.example...) 은 별도로 uninstall 필요. Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
2026-07-02 14:30:43 +09:00
parent 55d55225ab
commit bcbc7b440c
159 changed files with 2865 additions and 717 deletions
@@ -0,0 +1,237 @@
+package com.medithings.vesiscan.services.labdb
+
+import android.content.Context
+import android.os.Build
+import android.util.Log
+import com.medithings.vesiscan.ble.BleManager
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.withContext
+import okhttp3.MediaType.Companion.toMediaType
+import okhttp3.OkHttpClient
+import okhttp3.Request
+import okhttp3.RequestBody.Companion.toRequestBody
+import org.json.JSONArray
+import org.json.JSONObject
+import java.io.IOException
+import java.util.concurrent.TimeUnit
+
+sealed class LabdbException(message: String) : IOException(message)
+class PendingApprovalException : LabdbException("Device is awaiting administrator approval")
+class ReregisterRequiredException(message: String) : LabdbException(message)
+class RateLimitedException : LabdbException("Rate limit exceeded (10 req/min)")
+class LabdbApiError(val httpStatus: Int, val code: String, message: String) : LabdbException("$code ($httpStatus): $message")
+class LabdbNetworkError(cause: Throwable) : LabdbException("Network error: ${cause.message}")
+
+data class RegisterResult(val deviceId: String, val apiKey: String, val status: String, val message: String)
+data class StatusResult(val httpStatus: Int, val status: String, val deviceName: String?, val sessionCount: Int?)
+data class UploadResult(
+    val ok: Boolean,
+    val sessionId: String,
+    val created: Boolean,
+    val totalRecords: Int,
+    val inserted: Int,
+    val duplicates: Int,
+    val errors: Int,
+)
+
+/**
+ * https://labdb.medithings.net REST 클라이언트.
+ *
+ * 사용 순서:
+ *   1) register(context, appVersion) — 앱 첫 임상 모드 진입 시 1회
+ *   2) checkStatus() — 임상 화면 진입 시 매번
+ *   3) uploadJson(payload) — End Session 후 measurement.json 업로드
+ *
+ * 모든 메서드는 suspend, IO 디스패처에서 실행.
+ */
+object LabdbClient {
+    private const val TAG = "LabdbClient"
+    private const val BASE = "https://labdb.medithings.net/api/v1"
+    private const val APP_NAME = "VesiScan"
+    private val JSON = "application/json; charset=utf-8".toMediaType()
+
+    private val client: OkHttpClient by lazy {
+        OkHttpClient.Builder()
+            .connectTimeout(15, TimeUnit.SECONDS)
+            .readTimeout(60, TimeUnit.SECONDS)
+            .writeTimeout(60, TimeUnit.SECONDS)
+            .build()
+    }
+
+    /** 디바이스 등록 — 앱 생애 1회. 응답에 status='pending'이면 admin 승인 대기. */
+    suspend fun register(context: Context, appVersion: String): RegisterResult = withContext(Dispatchers.IO) {
+        val ble = BleManager.getInstance(context)
+        val body = JSONObject().apply {
+            put("appName", APP_NAME)
+            put("deviceName", "${Build.MANUFACTURER} ${Build.MODEL}")
+            ble.firmwareVersion.value.takeIf { it.isNotEmpty() }?.let { put("fwVersion", it) }
+            ble.hardwareVersion.value.takeIf { it.isNotEmpty() }?.let { put("hwNumber", it) }
+            ble.serialNumber.value.takeIf { it.isNotEmpty() }?.let { put("serialNumber", it) }
+            put("appVersion", appVersion)
+        }
+        sanitizeForJsonb(body)
+        Log.d(TAG, ">> POST /devices/register payload=$body")
+        val req = Request.Builder()
+            .url("$BASE/devices/register")
+            .post(body.toString().toRequestBody(JSON))
+            .build()
+        val (code, json) = exec(req)
+        when (code) {
+            200, 201 -> {
+                val deviceId = json.optString("deviceId")
+                val apiKey = json.optString("apiKey")
+                val status = json.optString("status", "pending")
+                val message = json.optString("message", "")
+                if (apiKey.isBlank()) throw LabdbApiError(code, "INVALID_RESPONSE", "register response missing apiKey")
+                LabdbCredentials.apiKey = apiKey
+                LabdbCredentials.deviceId = deviceId
+                LabdbCredentials.lastStatus = status
+                RegisterResult(deviceId, apiKey, status, message)
+            }
+            else -> throw apiError(code, json)
+        }
+    }
+
+    /** 디바이스 상태 확인. apiKey 무효 시 자격 자동 clear. */
+    suspend fun checkStatus(): StatusResult = withContext(Dispatchers.IO) {
+        val key = LabdbCredentials.apiKey
+            ?: return@withContext StatusResult(0, "not_registered", null, null)
+        val req = Request.Builder()
+            .url("$BASE/devices/status")
+            .header("X-API-Key", key)
+            .get()
+            .build()
+        val (code, json) = exec(req)
+        when (code) {
+            200 -> {
+                val status = json.optString("status", "unknown")
+                LabdbCredentials.lastStatus = status
+                StatusResult(
+                    httpStatus = 200,
+                    status = status,
+                    deviceName = json.optString("deviceName").ifBlank { null },
+                    sessionCount = if (json.has("sessionCount")) json.optInt("sessionCount") else null,
+                )
+            }
+            401, 404 -> {
+                LabdbCredentials.clear()
+                val err = json.optJSONObject("error")
+                val errCode = err?.optString("code") ?: if (code == 401) "INVALID_API_KEY" else "DEVICE_DELETED"
+                throw ReregisterRequiredException("$errCode: server requires re-registration")
+            }
+            else -> throw apiError(code, json)
+        }
+    }
+
+    /** /upload/json — measurement.json payload 한 번에 전송. testId+rowIndex 기반 idempotent. */
+    suspend fun uploadJson(payload: JSONObject): UploadResult = withContext(Dispatchers.IO) {
+        val key = LabdbCredentials.apiKey
+            ?: throw ReregisterRequiredException("No apiKey — register first")
+        // PostgreSQL JSONB rejects \u0000 — strip NULL/control chars from payload
+        sanitizeForJsonb(payload)
+        val req = Request.Builder()
+            .url("$BASE/upload/json")
+            .header("X-API-Key", key)
+            .post(payload.toString().toRequestBody(JSON))
+            .build()
+        val (code, json) = exec(req)
+        when (code) {
+            200, 201 -> UploadResult(
+                ok = json.optBoolean("ok", true),
+                sessionId = json.optString("sessionId"),
+                created = json.optBoolean("created", code == 201),
+                totalRecords = json.optInt("totalRecords"),
+                inserted = json.optInt("inserted"),
+                duplicates = json.optInt("duplicates"),
+                errors = json.optInt("errors"),
+            )
+            401 -> { LabdbCredentials.clear(); throw ReregisterRequiredException("INVALID_API_KEY") }
+            403 -> throw PendingApprovalException()
+            404 -> { LabdbCredentials.clear(); throw ReregisterRequiredException("DEVICE_DELETED") }
+            429 -> throw RateLimitedException()
+            else -> throw apiError(code, json)
+        }
+    }
+
+    /**
+     * 세션 삭제 — DELETE /api/v1/sessions/{testId}. Cascade로 모든 records 함께 제거.
+     * 204(No Content) 또는 200/404(이미 없음) = 성공. 401/403/등은 throw.
+     */
+    suspend fun deleteSession(testId: String): Boolean = withContext(Dispatchers.IO) {
+        val key = LabdbCredentials.apiKey
+            ?: throw ReregisterRequiredException("No apiKey — register first")
+        Log.d(TAG, ">> DELETE /sessions/$testId")
+        val req = Request.Builder()
+            .url("$BASE/sessions/$testId")
+            .header("X-API-Key", key)
+            .delete()
+            .build()
+        val (code, json) = exec(req)
+        when (code) {
+            200, 204, 404 -> true   // 404 = 이미 없음, 멱등 처리
+            401 -> { LabdbCredentials.clear(); throw ReregisterRequiredException("INVALID_API_KEY") }
+            403 -> throw PendingApprovalException()
+            429 -> throw RateLimitedException()
+            else -> throw apiError(code, json)
+        }
+    }
+
+    /**
+     * Recursively strip NULL (0x00) and other C0 control chars from every string value.
+     * PostgreSQL JSONB rejects  escapes with "unsupported Unicode escape sequence"
+     * (HTTP 500). BLE responses occasionally carry trailing 0x00 padding that survives
+     * String(US_ASCII) decoding + .trim().
+     */
+    internal fun sanitizeForJsonb(root: JSONObject) {
+        val keys = root.keys().asSequence().toList()
+        for (k in keys) {
+            when (val v = root.opt(k)) {
+                is String -> root.put(k, stripControl(v))
+                is JSONObject -> sanitizeForJsonb(v)
+                is JSONArray -> sanitizeArray(v)
+            }
+        }
+    }
+
+    private fun sanitizeArray(arr: JSONArray) {
+        for (i in 0 until arr.length()) {
+            when (val v = arr.opt(i)) {
+                is String -> arr.put(i, stripControl(v))
+                is JSONObject -> sanitizeForJsonb(v)
+                is JSONArray -> sanitizeArray(v)
+            }
+        }
+    }
+
+    private fun stripControl(s: String): String {
+        if (s.none { it.code == 0 || it.code == 127 || (it.code in 1..31 && it.code != 9 && it.code != 10 && it.code != 13) }) return s
+        val sb = StringBuilder(s.length)
+        for (c in s) {
+            val code = c.code
+            if (code == 0 || code == 127 || (code in 1..31 && code != 9 && code != 10 && code != 13)) continue
+            sb.append(c)
+        }
+        return sb.toString()
+    }
+
+    private fun apiError(code: Int, json: JSONObject): LabdbApiError {
+        val err = json.optJSONObject("error")
+        val errCode = err?.optString("code") ?: "HTTP_$code"
+        val msg = err?.optString("message") ?: json.toString().take(200)
+        return LabdbApiError(code, errCode, msg)
+    }
+
+    private fun exec(req: Request): Pair<Int, JSONObject> {
+        return try {
+            client.newCall(req).execute().use { res ->
+                val raw = res.body?.string().orEmpty()
+                Log.d(TAG, "<< ${req.method} ${req.url.encodedPath} → HTTP ${res.code} body=${raw.take(500)}")
+                val obj = if (raw.isBlank()) JSONObject() else runCatching { JSONObject(raw) }.getOrElse { JSONObject() }
+                res.code to obj
+            }
+        } catch (t: IOException) {
+            Log.w(TAG, "exec failed: ${req.method} ${req.url}", t)
+            throw LabdbNetworkError(t)
+        }
+    }
+}
@@ -0,0 +1,46 @@
+package com.medithings.vesiscan.services.labdb
+
+import com.medithings.vesiscan.services.KeychainService
+
+/**
+ * labdb (https://labdb.medithings.net) 자격 증명 저장소.
+ *
+ * apiKey/deviceId는 KeychainService(EncryptedSharedPreferences)에 안전 저장.
+ * 등록은 앱 첫 임상 모드 진입 시 1회만 — 재등록 시 pending device 누적되므로
+ * 401 INVALID_API_KEY / 404 DEVICE_DELETED 응답을 받았을 때만 clear() 후 재등록.
+ */
+object LabdbCredentials {
+    private const val KEY_API_KEY = "labdb.apiKey"
+    private const val KEY_DEVICE_ID = "labdb.deviceId"
+    private const val KEY_LAST_STATUS = "labdb.lastStatus"
+
+    var apiKey: String?
+        get() = KeychainService.load(KEY_API_KEY)
+        set(value) {
+            if (value == null) KeychainService.delete(KEY_API_KEY)
+            else KeychainService.save(KEY_API_KEY, value)
+        }
+
+    var deviceId: String?
+        get() = KeychainService.load(KEY_DEVICE_ID)
+        set(value) {
+            if (value == null) KeychainService.delete(KEY_DEVICE_ID)
+            else KeychainService.save(KEY_DEVICE_ID, value)
+        }
+
+    /** 마지막으로 GET /devices/status 응답에서 받은 상태 ("active"/"pending"/"revoked") */
+    var lastStatus: String?
+        get() = KeychainService.load(KEY_LAST_STATUS)
+        set(value) {
+            if (value == null) KeychainService.delete(KEY_LAST_STATUS)
+            else KeychainService.save(KEY_LAST_STATUS, value)
+        }
+
+    val isRegistered: Boolean get() = !apiKey.isNullOrBlank()
+
+    fun clear() {
+        apiKey = null
+        deviceId = null
+        lastStatus = null
+    }
+}
@@ -0,0 +1,235 @@
+package com.medithings.vesiscan.services.labdb
+
+import android.content.Context
+import android.util.Log
+import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.SupervisorJob
+import kotlinx.coroutines.launch
+import org.json.JSONArray
+import org.json.JSONObject
+import java.io.File
+import java.security.MessageDigest
+import java.text.SimpleDateFormat
+import java.util.Date
+import java.util.Locale
+
+/**
+ * 측정 폴더(measurement.json 포함) → labdb /upload/json 자동 업로드.
+ *
+ * 정책:
+ *   - End Session 시 ClinicalSessionStore가 uploadAsync(folder)를 호출
+ *   - 성공: folder/labdb_upload.json (응답 본문)
+ *   - 실패: folder/labdb_upload_error.json (에러 본문) — 폴더는 그대로 유지되어 수동 재시도 가능
+ *
+ * dataType = "001" (내부 임상 R&D — 외부 일반 VesiScan "000"과 구분).
+ * measurement.json의 meta.data_type을 우선 사용, 없으면 DEFAULT_DATA_TYPE fallback.
+ *
+ * testId:
+ *   - 폴더명 그대로 사용 (사용자 결정). 단 ^[A-Za-z0-9_-]{1,40}$ 제한 때문에
+ *     40자 초과 시 앞 31자 + "_" + 8자 SHA-1 prefix로 축약(unique 유지).
+ */
+object LabdbUploader {
+    private const val TAG = "LabdbUploader"
+    private const val DEFAULT_DATA_TYPE = "001"
+
+    private val scope = CoroutineScope(SupervisorJob() + Dispatchers.IO)
+    private val isoFmt: SimpleDateFormat
+        get() = SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss.SSSXXX", Locale.US)
+
+    /** 비동기 업로드 — fire-and-forget. 결과는 폴더 내 마커 파일로 확인. */
+    fun uploadAsync(context: Context, folder: File, onResult: ((Boolean, String) -> Unit)? = null) {
+        scope.launch {
+            val ok = runCatching { uploadBlocking(folder) }
+                .onFailure { Log.w(TAG, "upload failed: ${folder.name}", it) }
+                .getOrElse { e ->
+                    writeError(folder, e)
+                    onResult?.invoke(false, e.message ?: e.javaClass.simpleName)
+                    return@launch
+                }
+            onResult?.invoke(true, "uploaded: ${ok.inserted}/${ok.totalRecords} (dup=${ok.duplicates})")
+        }
+    }
+
+    /** 동기 업로드 — 재시도 버튼/자동 호출 양쪽 사용. */
+    suspend fun uploadBlocking(folder: File): UploadResult {
+        // 새 파일명 (measurement_<folderName>.json) 우선, 구 버전 (measurement.json) fallback
+        val measurementFile = File(folder, "measurement_${folder.name}.json").takeIf { it.exists() }
+            ?: File(folder, "measurement.json").takeIf { it.exists() }
+            ?: folder.listFiles()?.firstOrNull { it.name.startsWith("measurement_") && it.name.endsWith(".json") }
+            ?: throw IllegalStateException("measurement json not found in ${folder.name}")
+        val measurement = JSONObject(measurementFile.readText())
+        val payload = buildPayload(folder.name, measurement)
+        val result = LabdbClient.uploadJson(payload)
+        writeSuccess(folder, result)
+        return result
+    }
+
+    fun isUploaded(folder: File): Boolean = File(folder, "labdb_upload.json").exists()
+    fun lastError(folder: File): String? {
+        val f = File(folder, "labdb_upload_error.json")
+        return if (f.exists()) runCatching { JSONObject(f.readText()).optString("message") }.getOrNull() else null
+    }
+
+    /**
+     * 폴더에 해당하는 labdb 서버 세션 삭제.
+     * labdb_upload.json에 sessionId가 있으면 그것을 사용, 없으면 folderName → sanitizeTestId 변환.
+     * 미등록/미업로드 폴더의 testId도 그대로 호출 → labdb가 404로 응답 → 성공 처리.
+     */
+    suspend fun deleteSessionForFolder(folder: File): Boolean {
+        val uploadMarker = File(folder, "labdb_upload.json")
+        val testId = if (uploadMarker.exists()) {
+            runCatching { JSONObject(uploadMarker.readText()).optString("sessionId") }
+                .getOrNull()?.takeIf { it.isNotBlank() } ?: sanitizeTestId(folder.name)
+        } else {
+            sanitizeTestId(folder.name)
+        }
+        return if (testId.isNotBlank()) LabdbClient.deleteSession(testId) else true
+    }
+
+    /** measurement.json → labdb payload. 각 cycle = 1 record. */
+    private fun buildPayload(folderName: String, measurement: JSONObject): JSONObject {
+        val meta = measurement.optJSONObject("meta") ?: JSONObject()
+        val cycles = measurement.optJSONArray("cycles") ?: JSONArray()
+        val testId = sanitizeTestId(folderName)
+        val dataType = meta.optString("data_type").ifBlank { DEFAULT_DATA_TYPE }
+
+        val records = JSONArray()
+        for (i in 0 until cycles.length()) {
+            val cycle = cycles.optJSONObject(i) ?: continue
+            records.put(cycleToRecord(cycle, meta))
+        }
+
+        val params = JSONObject().apply {
+            // 측정 컨텍스트 — admin 콘솔에서 한눈에 보이도록
+            put("posture", meta.optString("posture"))
+            put("step", meta.optString("step"))
+            put("is_alignment", meta.optBoolean("is_alignment"))
+            put("examiner", meta.optString("examiner"))
+            meta.optString("subject_type").takeIf { it.isNotBlank() }?.let { put("subject_type", it) }
+            meta.optString("subject").takeIf { it.isNotBlank() }?.let { put("subject", it) }
+            if (meta.has("true_volume_ml")) put("true_volume_ml", meta.optDouble("true_volume_ml"))
+            if (meta.has("abdomen_thickness_mm")) put("abdomen_thickness_mm", meta.optDouble("abdomen_thickness_mm"))
+            meta.optString("firmware_version").takeIf { it.isNotBlank() }?.let { put("firmware_version", it) }
+            meta.optString("hardware_version").takeIf { it.isNotBlank() }?.let { put("hardware_version", it) }
+            meta.optString("serial_number").takeIf { it.isNotBlank() }?.let { put("serial_number", it) }
+            put("app_version", meta.optString("app_version_name"))
+            put("captured_cycles", cycles.length())
+        }
+
+        return JSONObject().apply {
+            put("testId", testId)
+            put("dataType", dataType)
+            // 서버는 sessionName을 export 파일명의 base로 사용 (날짜 포함이면 중복 안 붙임).
+            // 풀 폴더명을 그대로 보내야 분석 PC 다운로드 파일명과 앱 측 파일명이 일치.
+            put("sessionName", folderName)
+            put("memo", meta.optString("notes"))
+            meta.optLong("ended_at", 0L).takeIf { it > 0 }?.let {
+                put("savedAt", isoFmt.format(Date(it)))
+            }
+            put("params", params)
+            put("recordCount", records.length())
+            put("records", records)
+        }
+    }
+
+    private fun cycleToRecord(cycle: JSONObject, meta: JSONObject): JSONObject {
+        val rowIndex = cycle.optInt("cycle")
+        val tsMs = cycle.optLong("timestamp_ms")
+        val piezo = cycle.optJSONObject("piezo") ?: JSONObject()
+        val imuArr = cycle.optJSONArray("imu") ?: JSONArray()
+
+        // labdb 표준 sensor.imu는 단일 샘플. 우리는 cycle당 다수 샘플(FIFO 순)이라
+        // 마지막(=가장 최근, piezo 캡처 직전) 샘플을 sensor.imu에 넣고
+        // 전체를 sensor.imu_samples에 free field로 보존.
+        val latestImu = if (imuArr.length() > 0) imuArr.optJSONObject(imuArr.length() - 1) else null
+        val sensor = JSONObject().apply {
+            latestImu?.let {
+                put("imu", JSONObject().apply {
+                    put("ax", it.optDouble("ax"))
+                    put("ay", it.optDouble("ay"))
+                    put("az", it.optDouble("az"))
+                    put("gx", it.optDouble("gx"))
+                    put("gy", it.optDouble("gy"))
+                    put("gz", it.optDouble("gz"))
+                })
+            }
+            put("imu_samples", imuArr)
+            put("imu_sample_count", imuArr.length())
+        }
+
+        val channelsArr = JSONArray()
+        for (ch in 0..5) {
+            val data = piezo.optJSONArray("CH$ch") ?: continue
+            var peak = 0
+            var peakIdx = 0
+            for (i in 0 until data.length()) {
+                val v = data.optInt(i)
+                if (v > peak) { peak = v; peakIdx = i }
+            }
+            channelsArr.put(JSONObject().apply {
+                put("ch", ch)
+                put("peak", peak)
+                put("peakIdx", peakIdx)
+                put("data", data)
+            })
+        }
+
+        return JSONObject().apply {
+            put("rowIndex", rowIndex)
+            put("datetime", isoFmt.format(Date(tsMs)))
+            put("commandType", "MTB")
+            put("sensor", sensor)
+            put("channels", channelsArr)
+            // Alignment metadata (alignment session 의 cycle 일 때만 채워짐) — labdb 서버가
+            // raw.json export 시 함께 내려줘 분석 PC 에서 phase 별 frame 분석 가능.
+            if (cycle.has("align_phase")) {
+                put("align_phase", cycle.optString("align_phase"))
+                put("align_score", cycle.optInt("align_score"))
+                cycle.optString("align_hint").takeIf { it.isNotBlank() }?.let { put("align_hint", it) }
+                cycle.optString("align_icon").takeIf { it.isNotBlank() }?.let { put("align_icon", it) }
+                cycle.optJSONArray("align_detected")?.let { put("align_detected", it) }
+                cycle.optJSONArray("align_urine_lens")?.let { put("align_urine_lens", it) }
+            }
+        }
+    }
+
+    /** ^[A-Za-z0-9_-]{1,40}$ 강제. 40자 초과 시 앞 31자 + "_" + 8자 SHA-1 prefix. */
+    private fun sanitizeTestId(raw: String): String {
+        // - 와 _ 이외 특수문자 제거
+        val cleaned = raw.replace(Regex("[^A-Za-z0-9_-]"), "_")
+        if (cleaned.length <= 40) return cleaned
+        val hash = MessageDigest.getInstance("SHA-1").digest(cleaned.toByteArray())
+            .joinToString("") { "%02x".format(it) }.take(8)
+        return cleaned.take(31) + "_" + hash
+    }
+
+    private fun writeSuccess(folder: File, r: UploadResult) {
+        val body = JSONObject().apply {
+            put("ok", r.ok)
+            put("sessionId", r.sessionId)
+            put("created", r.created)
+            put("totalRecords", r.totalRecords)
+            put("inserted", r.inserted)
+            put("duplicates", r.duplicates)
+            put("errors", r.errors)
+            put("uploadedAt", isoFmt.format(Date()))
+        }
+        File(folder, "labdb_upload.json").writeText(body.toString(2))
+        // 이전 실패 마커가 있었다면 정리
+        File(folder, "labdb_upload_error.json").delete()
+    }
+
+    private fun writeError(folder: File, t: Throwable) {
+        val body = JSONObject().apply {
+            put("error", t.javaClass.simpleName)
+            put("message", t.message ?: "")
+            if (t is LabdbApiError) {
+                put("httpStatus", t.httpStatus)
+                put("code", t.code)
+            }
+            put("failedAt", isoFmt.format(Date()))
+        }
+        File(folder, "labdb_upload_error.json").writeText(body.toString(2))
+    }
+}