From 1b89e62d5f8b30c6dceb0d39f538d283238e7a8a Mon Sep 17 00:00:00 2001 From: Seongho Bae Date: Mon, 10 Aug 2026 11:05:15 +0900 Subject: [PATCH 01/11] test(etl): reject invalid amounts before persistence --- .../EtlServiceAmountIntegrityTest.java | 71 +++++++++++++++++++ 1 file changed, 71 insertions(+) create mode 100644 etl-service/src/test/java/com/xtrmetl/etl/service/EtlServiceAmountIntegrityTest.java diff --git a/etl-service/src/test/java/com/xtrmetl/etl/service/EtlServiceAmountIntegrityTest.java b/etl-service/src/test/java/com/xtrmetl/etl/service/EtlServiceAmountIntegrityTest.java new file mode 100644 index 00000000..d905af5d --- /dev/null +++ b/etl-service/src/test/java/com/xtrmetl/etl/service/EtlServiceAmountIntegrityTest.java @@ -0,0 +1,71 @@ +package com.xtrmetl.etl.service; + +import com.fasterxml.jackson.databind.ObjectMapper; +import org.junit.jupiter.api.BeforeEach; +import org.junit.jupiter.api.Test; +import org.junit.jupiter.params.ParameterizedTest; +import org.junit.jupiter.params.provider.ValueSource; +import org.springframework.jdbc.core.JdbcTemplate; + +import static org.junit.jupiter.api.Assertions.assertSame; +import static org.junit.jupiter.api.Assertions.assertThrows; +import static org.mockito.Mockito.mock; +import static org.mockito.Mockito.verifyNoInteractions; + +/** + * Proves that invalid monetary input is rejected rather than converted into a legitimate zero. + */ +class EtlServiceAmountIntegrityTest { + + private JdbcTemplate jdbcTemplate; + private EtlService etlService; + + @BeforeEach + void setUp() { + jdbcTemplate = mock(JdbcTemplate.class); + EtlBatchProperties properties = new EtlBatchProperties(); + properties.setMaxPayloadBytes(65_536); + properties.setMaxBatchRecords(100); + etlService = new EtlService(jdbcTemplate, new ObjectMapper(), properties); + } + + @ParameterizedTest + @ValueSource(strings = { + "", + "not-a-number", + "123456789012345678901234567890123456789", + "0.0000000000000000001", + "1E+19" + }) + void rejectsInvalidOrUnsupportedAmountsBeforeJdbc(String amount) { + EtlRequestException exception = assertThrows( + EtlRequestException.class, + () -> etlService.processData(jsonRecord("record_alpha", amount)) + ); + + assertSame(EtlRequestError.INVALID_RECORD, exception.error()); + verifyNoInteractions(jdbcTemplate); + } + + @Test + void invalidAmountMakesTheWholeBatchFailBeforeAnyJdbcWrite() { + String payload = """ + [ + {"id":"record_alpha","amount":"10.00"}, + {"id":"record_beta","amount":"not-a-number"} + ] + """; + + EtlRequestException exception = assertThrows( + EtlRequestException.class, + () -> etlService.processData(payload) + ); + + assertSame(EtlRequestError.INVALID_RECORD, exception.error()); + verifyNoInteractions(jdbcTemplate); + } + + private static String jsonRecord(String id, String amount) { + return "[{\"id\":\"" + id + "\",\"amount\":\"" + amount + "\"}]"; + } +} From 2530cf98cfdf4ab78bcdda7e7449768157e6f0cc Mon Sep 17 00:00:00 2001 From: Seongho Bae Date: Mon, 10 Aug 2026 11:10:18 +0900 Subject: [PATCH 02/11] fix(etl): fail closed on invalid amount values --- .../com/xtrmetl/etl/service/EtlService.java | 19 ++++++++++--------- 1 file changed, 10 insertions(+), 9 deletions(-) diff --git a/etl-service/src/main/java/com/xtrmetl/etl/service/EtlService.java b/etl-service/src/main/java/com/xtrmetl/etl/service/EtlService.java index 6bb32a15..2557ec04 100644 --- a/etl-service/src/main/java/com/xtrmetl/etl/service/EtlService.java +++ b/etl-service/src/main/java/com/xtrmetl/etl/service/EtlService.java @@ -400,18 +400,19 @@ private String transformValue(String key, @Nullable JsonNode valueNode) { } private String formatAmount(String value) { + final BigDecimal amount; try { - BigDecimal amount = new BigDecimal(value.trim()); - int scale = amount.scale(); - if (amount.precision() > MAX_AMOUNT_PRECISION - || scale < -MAX_AMOUNT_ABSOLUTE_SCALE - || scale > MAX_AMOUNT_ABSOLUTE_SCALE) { - return "0.00"; - } - return amount.setScale(2, RoundingMode.HALF_UP).toPlainString(); + amount = new BigDecimal(value.trim()); } catch (NumberFormatException exception) { - return "0.00"; + throw invalidRecord(); + } + int scale = amount.scale(); + if (amount.precision() > MAX_AMOUNT_PRECISION + || scale < -MAX_AMOUNT_ABSOLUTE_SCALE + || scale > MAX_AMOUNT_ABSOLUTE_SCALE) { + throw invalidRecord(); } + return amount.setScale(2, RoundingMode.HALF_UP).toPlainString(); } private record StoredIdempotencyRecord(String requestDigest, String responseBody) { From c0a3323713d726df842c8e4de10f53e57f7544da Mon Sep 17 00:00:00 2001 From: Seongho Bae Date: Mon, 10 Aug 2026 11:11:22 +0900 Subject: [PATCH 03/11] test(etl): align legacy amount expectations with fail-closed validation --- .../xtrmetl/etl/service/EtlServiceTest.java | 19 +++++++++++-------- 1 file changed, 11 insertions(+), 8 deletions(-) diff --git a/etl-service/src/test/java/com/xtrmetl/etl/service/EtlServiceTest.java b/etl-service/src/test/java/com/xtrmetl/etl/service/EtlServiceTest.java index 5cc4ca06..f386131c 100644 --- a/etl-service/src/test/java/com/xtrmetl/etl/service/EtlServiceTest.java +++ b/etl-service/src/test/java/com/xtrmetl/etl/service/EtlServiceTest.java @@ -129,12 +129,16 @@ void formatsAmountsDeterministically(String input, String expected) { } @Test - void fallsBackToZeroForInvalidAmount() { - etlService.processData( - "[{\"id\":\"record_alpha\",\"amount\":\"not-a-number\"}]" + void rejectsInvalidAmountInsteadOfManufacturingZero() { + EtlRequestException exception = assertThrows( + EtlRequestException.class, + () -> etlService.processData( + "[{\"id\":\"record_alpha\",\"amount\":\"not-a-number\"}]" + ) ); - verify(jdbcTemplate).update(anyString(), contains("AMOUNT:0.00")); + assertSame(EtlRequestError.INVALID_RECORD, exception.error()); + verifyNoInteractions(jdbcTemplate); } @Test @@ -154,19 +158,18 @@ void retainsUnknownAndUnicodeFields() { } @Test - void preservesEmptyOptionalValues() { + void preservesEmptyOptionalNameAndEmailValues() { etlService.processData(""" [{ "id":"record_alpha", "name":"", - "email":"", - "amount":"" + "email":"" }] """); verify(jdbcTemplate).update( anyString(), - eq("ID:record_alpha,NAME:,EMAIL:,AMOUNT:0.00,") + eq("ID:record_alpha,NAME:,EMAIL:,") ); } } From 4f783a86bbbb80940d2b31efa124d229fb4bfb7d Mon Sep 17 00:00:00 2001 From: Seongho Bae Date: Mon, 10 Aug 2026 11:15:22 +0900 Subject: [PATCH 04/11] test(etl): align extreme amount safety with fail-closed validation --- .../etl/service/EtlServiceBatchSafetyTest.java | 13 +++++++------ 1 file changed, 7 insertions(+), 6 deletions(-) diff --git a/etl-service/src/test/java/com/xtrmetl/etl/service/EtlServiceBatchSafetyTest.java b/etl-service/src/test/java/com/xtrmetl/etl/service/EtlServiceBatchSafetyTest.java index b32e9a66..eaf9cc3b 100644 --- a/etl-service/src/test/java/com/xtrmetl/etl/service/EtlServiceBatchSafetyTest.java +++ b/etl-service/src/test/java/com/xtrmetl/etl/service/EtlServiceBatchSafetyTest.java @@ -274,15 +274,16 @@ void usesLocaleIndependentTextAndDecimalTransformations() { } @Test - void boundsExtremeDecimalInputsWithoutHugePlainStringExpansion() { + void rejectsExtremeDecimalInputsWithoutHugePlainStringExpansion() { EtlService service = service(); - service.processData("[{\"id\":\"record_alpha\",\"amount\":\"1E+1000000\"}]"); - - verify(jdbcTemplate).update( - "INSERT INTO processed_data (data) VALUES (?)", - "ID:record_alpha,AMOUNT:0.00," + EtlRequestException exception = assertThrows( + EtlRequestException.class, + () -> service.processData("[{\"id\":\"record_alpha\",\"amount\":\"1E+1000000\"}]") ); + + assertSame(EtlRequestError.INVALID_RECORD, exception.error()); + verifyNoInteractions(jdbcTemplate); } @Test From 02833f64ceb25b5504b53b6abf0ba130860c3e66 Mon Sep 17 00:00:00 2001 From: Seongho Bae Date: Mon, 10 Aug 2026 11:17:54 +0900 Subject: [PATCH 05/11] test(docs): require fail-closed amount integrity contract --- .../etl/documentation/EtlBatchDocsAlignmentTest.java | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/etl-service/src/test/java/com/xtrmetl/etl/documentation/EtlBatchDocsAlignmentTest.java b/etl-service/src/test/java/com/xtrmetl/etl/documentation/EtlBatchDocsAlignmentTest.java index 6ffb4cdd..89f78c43 100644 --- a/etl-service/src/test/java/com/xtrmetl/etl/documentation/EtlBatchDocsAlignmentTest.java +++ b/etl-service/src/test/java/com/xtrmetl/etl/documentation/EtlBatchDocsAlignmentTest.java @@ -45,6 +45,17 @@ void runbookStatesAdmissionRollbackAndIngressBoundaries() throws IOException { assertTrue(runbook.contains("Duplicate field names are rejected")); } + @Test + void runbookRejectsInvalidAmountsInsteadOfManufacturingZero() throws IOException { + String runbook = read("docs/etl/bounded-atomic-batches.md"); + + assertTrue(runbook.contains( + "Malformed, blank, excessive-precision, or extreme-scale `AMOUNT` values are rejected" + )); + assertTrue(runbook.contains("before the first JDBC call")); + assertFalse(runbook.contains("legacy fallback `0.00`")); + } + @Test void configurationAndChangelogUseTheSameLimits() throws IOException { String application = read("etl-service/src/main/resources/application.yml"); From dfd318fca2128ecd86827201609852da5c61a932 Mon Sep 17 00:00:00 2001 From: Seongho Bae Date: Mon, 10 Aug 2026 11:22:25 +0900 Subject: [PATCH 06/11] docs(etl): document fail-closed amount integrity --- docs/etl/bounded-atomic-batches.md | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/docs/etl/bounded-atomic-batches.md b/docs/etl/bounded-atomic-batches.md index f9cf62db..9e78b0f2 100644 --- a/docs/etl/bounded-atomic-batches.md +++ b/docs/etl/bounded-atomic-batches.md @@ -43,11 +43,13 @@ Fields are transformed directly from the Jackson JSON tree; values are not split - Field names use locale-independent uppercase normalization and must remain unique after normalization. - `NAME` values use locale-independent uppercase conversion. - `EMAIL` values use locale-independent lowercase conversion. -- `AMOUNT` values use `BigDecimal`, `HALF_UP`, scale `2`, and `toPlainString()`. -- Invalid, excessive-precision, or extreme-scale amounts retain the legacy fallback `0.00` without expanding attacker-controlled exponents into huge strings. +- Valid `AMOUNT` values use `BigDecimal`, `HALF_UP`, scale `2`, and `toPlainString()`; a genuine numeric zero therefore remains the legitimate transformed value `0.00`. +- Malformed, blank, excessive-precision, or extreme-scale `AMOUNT` values are rejected as invalid records before the first JDBC call. Because the complete batch is transformed before persistence, one invalid amount causes the request to fail with no database writes instead of manufacturing a valid-looking zero. - Nested arrays and objects are retained as compact JSON instead of collapsing to empty text. - Response lines remain `Processed: ` in input order. Identifier whitespace, ISO control, Unicode format-control, Unicode line-separator characters, and length are bounded so one record cannot inject, visually reorder, conceal, or amplify response lines. +The fail-closed amount policy prevents new malformed monetary input from becoming indistinguishable from genuine zero after persistence. Historical `processed_data` rows created under the prior fallback cannot be reliably classified after the fact solely from a stored `0.00`; reconciliation therefore requires upstream/source evidence rather than an automated destructive rewrite. + ## Configuration Preferred keys use the mightyETL product namespace; compatibility keys remain available: @@ -72,7 +74,8 @@ Values outside the supported range fail configuration binding instead of silentl - Keep the payload limit aligned with gateway and ingress body-size limits. The service-level check occurs after the MVC stack has materialized the request string and is not a substitute for edge enforcement. - Keep the record limit below the transaction size that the target database can commit within the request timeout and lock budget. -- Monitor request latency, transaction duration, rollback rate, database pool wait time, and rejected payload/record-limit errors before raising either limit. +- Monitor request latency, transaction duration, rollback rate, database pool wait time, and deterministic invalid-record rejection rates before raising either limit. +- Treat an increased invalid-amount rejection rate as upstream data-quality evidence. Do not log the raw amount or payload merely to diagnose the failure; use source-system reconciliation under purpose-bound access. - Use descriptive string identifiers. Numeric JSON identifier types are rejected to keep identifier contracts explicit and stable across systems. ## Remaining boundary From f7ba515c204ae0f69a43e2f5ba08e93f662155ba Mon Sep 17 00:00:00 2001 From: Seongho Bae Date: Mon, 10 Aug 2026 11:23:31 +0900 Subject: [PATCH 07/11] test(docs): require amount integrity changelog evidence --- .../etl/documentation/EtlBatchDocsAlignmentTest.java | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/etl-service/src/test/java/com/xtrmetl/etl/documentation/EtlBatchDocsAlignmentTest.java b/etl-service/src/test/java/com/xtrmetl/etl/documentation/EtlBatchDocsAlignmentTest.java index 89f78c43..6a0cfecd 100644 --- a/etl-service/src/test/java/com/xtrmetl/etl/documentation/EtlBatchDocsAlignmentTest.java +++ b/etl-service/src/test/java/com/xtrmetl/etl/documentation/EtlBatchDocsAlignmentTest.java @@ -67,6 +67,15 @@ void configurationAndChangelogUseTheSameLimits() throws IOException { assertTrue(changelog.contains("retry only transient Spring data-access failures")); } + @Test + void changelogRecordsFailClosedAmountIntegrity() throws IOException { + String changelog = read("CHANGELOG.md"); + + assertTrue(changelog.contains("invalid `AMOUNT` values fail closed")); + assertTrue(changelog.contains("genuine zero")); + assertFalse(changelog.contains("invalid `AMOUNT` values to `0.00`")); + } + private static String read(String relativePath) throws IOException { return Files.readString(projectRoot().resolve(relativePath), StandardCharsets.UTF_8); } From 14e1bbcd77107d37ca0106c44e638e5aaa707657 Mon Sep 17 00:00:00 2001 From: Seongho Bae Date: Mon, 10 Aug 2026 14:14:19 +0900 Subject: [PATCH 08/11] docs(etl): record fail-closed amount integrity --- CHANGELOG.md | 176 +-------------------------------------------------- 1 file changed, 2 insertions(+), 174 deletions(-) diff --git a/CHANGELOG.md b/CHANGELOG.md index 45b08b8c..0b161b5b 100644 --- a/CHANGELOG.md +++ b/CHANGELOG.md @@ -9,6 +9,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0 ### Changed +- Invalid `AMOUNT` values fail closed before persistence instead of being rewritten to `0.00`, preserving the distinction from a genuine zero. - Durable `POST /api/etl/jobs` submissions now return RFC 9110 `202 Accepted`, a stable pending-job representation, `Location` status-monitor metadata, and explicit replay metadata without changing the synchronous `/api/etl/process` contract. The incomplete intake controller is fail-closed and requires explicit `xtrmetl.etl.jobs.intake-enabled=true` operator opt-in until worker execution and terminal payload clearing are implemented. - Concurrent requests using the same authenticated-principal-scoped semantic idempotency key now return immediate RFC 9457 `409 etl_idempotency_request_in_progress` responses through PostgreSQL `pg_try_advisory_xact_lock`; retries after completion still replay the committed response. - `POST /api/etl/process` now supports optional authenticated-principal-scoped `Idempotency-Key` retries with atomic target writes, durable response replay, payload-conflict rejection, and explicit replay response metadata. @@ -77,177 +78,4 @@ existing xtrmETL platform. - Technology stack reference - Development guidelines -2. **PRD.md** (608 lines) - - Executive summary and product vision - - Problem statement analysis - - Solution overview with core capabilities - - Functional requirements (FR-CDC-1 through FR-GATE-1) - - Non-functional requirements (Performance, Reliability, Security, etc.) - - Complete data model specifications - - API specifications with examples - - Deployment architecture - - Use cases and scenarios - - Future enhancements roadmap - - Success metrics and KPIs - - Risk assessment and mitigation strategies - - Comprehensive glossary - -3. **ARCHITECTURE.md** (633 lines) - - High-level system architecture diagrams - - Service communication patterns (synchronous/asynchronous) - - Detailed data flow diagrams for: - - ETL processing - - CDC event capture - - Authentication flow - - Service discovery and registration - - Security architecture - - Monitoring and observability stack - - Deployment architectures (single-node and multi-node) - - Debezium integration details - - Spring Retry mechanism - - Network and port configuration - - Scalability considerations - -4. **SUMMARY_KR.md** (206 lines) - - Korean language summary for stakeholders - - Project purpose and goals - - Key features overview - - System architecture summary - - Technology stack - - Use cases - - API specifications - - Quick start guide - - Future improvements - - Technical debt assessment - -#### Project Understanding - -Through code analysis, identified the platform as: - -- **Enterprise ETL and CDC Platform** -- Microservices-based architecture using Spring Cloud -- Real-time Change Data Capture using Debezium -- Data transformation pipelines with parallel processing -- JWT-based security with role-based access control -- Event streaming via Apache Kafka -- Service discovery with Netflix Eureka -- Distributed tracing with Zipkin - -#### Key Components Documented - -1. **CDC Service** (Port 8001) - - PostgreSQL change data capture - - Debezium embedded engine - - Kafka event publishing - - Real-time monitoring capabilities - -2. **ETL Service** (Port 8000) - - JSON data processing - - Parallel record processing - - Configurable transformations - - Automatic retry mechanism - - Target database loading - -3. **Zuul Gateway** (Port 8080) - - API Gateway with routing - - JWT authentication filter - - Load balancing - - Request routing to services - -4. **Eureka Server** (Port 8761) - - Service discovery - - Service registration - - Health monitoring - -5. **Config Server** (Port 8888) - - Centralized configuration (planned) - -6. **Zipkin** (Port 9412) - - Distributed tracing - - Performance monitoring - -#### Technology Stack Documented - -- Java 25 -- Spring Boot 2.7.14 -- Spring Cloud 2021.0.8 -- Debezium 2.3.x - 2.5.x -- PostgreSQL 12+ -- Apache Kafka -- Netflix Zuul -- Netflix Eureka -- Maven - -#### Identified Technical Debt - -- Common module referenced but not implemented -- MyBatis dependencies present but unused -- Redis integration configured but not utilized -- Config Server implemented but not actively used -- Missing Spring Boot Actuator health checks - -#### Future Enhancements Documented - -- Multi-database CDC support (MySQL, Oracle, SQL Server) -- Custom transformation functions -- Data quality validation -- Web UI for configuration and monitoring -- Schema registry integration -- Dead Letter Queue for failed messages -- Enhanced metrics dashboard - -### Files Changed - -- `CHANGELOG.md` (new) -- `README.md` (new) -- `PRD.md` (new) -- `ARCHITECTURE.md` (new) -- `SUMMARY_KR.md` (new) - -### Issue Resolved - -This release addresses the GitHub issue requesting reverse-engineering of the program's purpose and PRD creation. The issue noted: "이 프로그램이 무엇을 하고 싶었던 프로그램인지 역추적하고 PRD 작성. 아마도 데이터베이스 CDC 프로그램이었던 것 같음." - -**Confirmation**: Yes, this is a database CDC (Change Data Capture) program, specifically an enterprise-grade ETL and CDC platform for real-time data integration. - -### Documentation Statistics - -- Total lines of documentation: 1,925 -- Total files created: 4 -- Total size: ~75 KB -- Languages: English (primary), Korean (summary) - -### Related Documents - -For more information, see: - -- [README.md](README.md) - Quick start guide -- [PRD.md](PRD.md) - Product Requirements Document -- [ARCHITECTURE.md](ARCHITECTURE.md) - Technical architecture -- [SUMMARY_KR.md](SUMMARY_KR.md) - Korean summary -- Original design notes (Korean) in project files - ---- - -## Notes on Versioning - -Since this is documentation work on an existing codebase: - -- Version 1.0.0 represents the first documented release -- The actual codebase existed before this documentation -- Future versions will track both code and documentation changes - -## Changelog Maintenance - -This changelog will be updated: - -- When new features are added -- When bugs are fixed -- When documentation is significantly updated -- For each release or milestone - ---- - -**Changelog Version**: 1.0 -**Last Updated**: 2026-08-04 -**Maintained By**: Development Team \ No newline at end of file +2. **PRD.md** (608 lines) \ No newline at end of file From 311d1efaf793a5e30b28a97eadcb074a23988b26 Mon Sep 17 00:00:00 2001 From: Seongho Bae Date: Mon, 10 Aug 2026 14:25:10 +0900 Subject: [PATCH 09/11] fix(docs): restore changelog history around amount integrity --- CHANGELOG.md | 177 ++++++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 175 insertions(+), 2 deletions(-) diff --git a/CHANGELOG.md b/CHANGELOG.md index 0b161b5b..ea1cf305 100644 --- a/CHANGELOG.md +++ b/CHANGELOG.md @@ -37,7 +37,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0 - CDC target SPI registry (`kafka`, `jdbc-replica`) for any-to-any routing scaffold. - `etl-service` `xtrmetl.connectors.*` disabled config keys for Databricks/Snowflake/Qlik. - Dual-read config aliases: `mightyetl.*` preferred → `xtrmetl.*` (`MightyEtlConfigAliasEnvironmentPostProcessor`). -- Configurable replica tables (`xtrmetl.replica.tables`) for `(id,data)`-shaped tables. +- Configurable replica tables (`xtrmetl.replica.tables`) for `(id, data)`-shaped tables. - Optional CDC canonical-map counters (`xtrmetl.cdc.canonical-map-enabled`). - ETL connector catalog API `GET /api/etl/connectors` + scaffold enable guard. - CDC replication slot lag probe on `GET /api/cdc/status` (`ReplicationSlotProbe`). @@ -78,4 +78,177 @@ existing xtrmETL platform. - Technology stack reference - Development guidelines -2. **PRD.md** (608 lines) \ No newline at end of file +2. **PRD.md** (608 lines) + - Executive summary and product vision + - Problem statement analysis + - Solution overview with core capabilities + - Functional requirements (FR-CDC-1 through FR-GATE-1) + - Non-functional requirements (Performance, Reliability, Security, etc.) + - Complete data model specifications + - API specifications with examples + - Deployment architecture + - Use cases and scenarios + - Future enhancements roadmap + - Success metrics and KPIs + - Risk assessment and mitigation strategies + - Comprehensive glossary + +3. **ARCHITECTURE.md** (633 lines) + - High-level system architecture diagrams + - Service communication patterns (synchronous/asynchronous) + - Detailed data flow diagrams for: + - ETL processing + - CDC event capture + - Authentication flow + - Service discovery and registration + - Security architecture + - Monitoring and observability stack + - Deployment architectures (single-node and multi-node) + - Debezium integration details + - Spring Retry mechanism + - Network and port configuration + - Scalability considerations + +4. **SUMMARY_KR.md** (206 lines) + - Korean language summary for stakeholders + - Project purpose and goals + - Key features overview + - System architecture summary + - Technology stack + - Use cases + - API specifications + - Quick start guide + - Future improvements + - Technical debt assessment + +#### Project Understanding + +Through code analysis, identified the platform as: + +- **Enterprise ETL and CDC Platform** +- Microservices-based architecture using Spring Cloud +- Real-time Change Data Capture using Debezium +- Data transformation pipelines with parallel processing +- JWT-based security with role-based access control +- Event streaming via Apache Kafka +- Service discovery with Netflix Eureka +- Distributed tracing with Zipkin + +#### Key Components Documented + +1. **CDC Service** (Port 8001) + - PostgreSQL change data capture + - Debezium embedded engine + - Kafka event publishing + - Real-time monitoring capabilities + +2. **ETL Service** (Port 8000) + - JSON data processing + - Parallel record processing + - Configurable transformations + - Automatic retry mechanism + - Target database loading + +3. **Zuul Gateway** (Port 8080) + - API Gateway with routing + - JWT authentication filter + - Load balancing + - Request routing to services + +4. **Eureka Server** (Port 8761) + - Service discovery + - Service registration + - Health monitoring + +5. **Config Server** (Port 8888) + - Centralized configuration (planned) + +6. **Zipkin** (Port 9412) + - Distributed tracing + - Performance monitoring + +#### Technology Stack Documented + +- Java 25 +- Spring Boot 2.7.14 +- Spring Cloud 2021.0.8 +- Debezium 2.3.x - 2.5.x +- PostgreSQL 12+ +- Apache Kafka +- Netflix Zuul +- Netflix Eureka +- Maven + +#### Identified Technical Debt + +- Common module referenced but not implemented +- MyBatis dependencies present but unused +- Redis integration configured but not utilized +- Config Server implemented but not actively used +- Missing Spring Boot Actuator health checks + +#### Future Enhancements Documented + +- Multi-database CDC support (MySQL, Oracle, SQL Server) +- Custom transformation functions +- Data quality validation +- Web UI for configuration and monitoring +- Schema registry integration +- Dead Letter Queue for failed messages +- Enhanced metrics dashboard + +### Files Changed + +- `CHANGELOG.md` (new) +- `README.md` (new) +- `PRD.md` (new) +- `ARCHITECTURE.md` (new) +- `SUMMARY_KR.md` (new) + +### Issue Resolved + +This release addresses the GitHub issue requesting reverse-engineering of the program's purpose and PRD creation. The issue noted: "이 프로그램이 무엇을 하고 싶었던 프로그램인지 역추적하고 PRD 작성. 아마도 데이터베이스 CDC 프로그램이었던 것 같음." + +**Confirmation**: Yes, this is a database CDC (Change Data Capture) program, specifically an enterprise-grade ETL and CDC platform for real-time data integration. + +### Documentation Statistics + +- Total lines of documentation: 1,925 +- Total files created: 4 +- Total size: ~75 KB +- Languages: English (primary), Korean (summary) + +### Related Documents + +For more information, see: + +- [README.md](README.md) - Quick start guide +- [PRD.md](PRD.md) - Product Requirements Document +- [ARCHITECTURE.md](ARCHITECTURE.md) - Technical architecture +- [SUMMARY_KR.md](SUMMARY_KR.md) - Korean summary +- Original design notes (Korean) in project files + +--- + +## Notes on Versioning + +Since this is documentation work on an existing codebase: + +- Version 1.0.0 represents the first documented release +- The actual codebase existed before this documentation +- Future versions will track both code and documentation changes + +## Changelog Maintenance + +This changelog will be updated: + +- When new features are added +- When bugs are fixed +- When documentation is significantly updated +- For each release or milestone + +--- + +**Changelog Version**: 1.0 +**Last Updated**: 2026-08-04 +**Maintained By**: Development Team \ No newline at end of file From 313571e6e8ede44a6689a22d81bfcfb9eb1f3668 Mon Sep 17 00:00:00 2001 From: Seongho Bae Date: Mon, 10 Aug 2026 14:28:05 +0900 Subject: [PATCH 10/11] fix(docs): remove unintended changelog whitespace drift --- CHANGELOG.md | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/CHANGELOG.md b/CHANGELOG.md index ea1cf305..f1033cd1 100644 --- a/CHANGELOG.md +++ b/CHANGELOG.md @@ -37,7 +37,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0 - CDC target SPI registry (`kafka`, `jdbc-replica`) for any-to-any routing scaffold. - `etl-service` `xtrmetl.connectors.*` disabled config keys for Databricks/Snowflake/Qlik. - Dual-read config aliases: `mightyetl.*` preferred → `xtrmetl.*` (`MightyEtlConfigAliasEnvironmentPostProcessor`). -- Configurable replica tables (`xtrmetl.replica.tables`) for `(id, data)`-shaped tables. +- Configurable replica tables (`xtrmetl.replica.tables`) for `(id,data)`-shaped tables. - Optional CDC canonical-map counters (`xtrmetl.cdc.canonical-map-enabled`). - ETL connector catalog API `GET /api/etl/connectors` + scaffold enable guard. - CDC replication slot lag probe on `GET /api/cdc/status` (`ReplicationSlotProbe`). From 27707b72ba1865fe86e24dfbecdc740a586a258b Mon Sep 17 00:00:00 2001 From: Seongho Bae Date: Mon, 10 Aug 2026 15:11:11 +0900 Subject: [PATCH 11/11] docs(etl): record fail-closed amount integrity --- CHANGELOG.md | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/CHANGELOG.md b/CHANGELOG.md index f1033cd1..ed3a22ad 100644 --- a/CHANGELOG.md +++ b/CHANGELOG.md @@ -9,7 +9,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0 ### Changed -- Invalid `AMOUNT` values fail closed before persistence instead of being rewritten to `0.00`, preserving the distinction from a genuine zero. +- ETL amount integrity: invalid `AMOUNT` values fail closed before persistence instead of being rewritten to `0.00`, preserving the distinction from a genuine zero. - Durable `POST /api/etl/jobs` submissions now return RFC 9110 `202 Accepted`, a stable pending-job representation, `Location` status-monitor metadata, and explicit replay metadata without changing the synchronous `/api/etl/process` contract. The incomplete intake controller is fail-closed and requires explicit `xtrmetl.etl.jobs.intake-enabled=true` operator opt-in until worker execution and terminal payload clearing are implemented. - Concurrent requests using the same authenticated-principal-scoped semantic idempotency key now return immediate RFC 9457 `409 etl_idempotency_request_in_progress` responses through PostgreSQL `pg_try_advisory_xact_lock`; retries after completion still replay the committed response. - `POST /api/etl/process` now supports optional authenticated-principal-scoped `Idempotency-Key` retries with atomic target writes, durable response replay, payload-conflict rejection, and explicit replay response metadata.