PostgreSQL

Render에 올려둔 Rails 서비스 6개가 전부 각자 다른 에러를 토해내고 있었다. 하나씩 로그를 까보니 공통 패턴도 있고, 프로젝트마다 고유한 문제도 있었다. 한 세션에서 전부 수정하고 배포까지 마친 과정을 정리한다. 전체 상황 Render API로 서비스 6개의 로그를 일괄 조회했다. 결과: 서비스 주요 에러 서비스 A ERB 문법 에러로 500 (이미 커밋됐지만 미배포) 서비스 B Stoplight Light#run 블록 에러 + Telegram 파싱 에러 서비스 C solid_cache_entries 테이블 누락 서비스 D PG::UndefinedColumn + solid_cache 누락 서비스 E PG::DuplicateTable sessions + Sentry 초기화 에러 서비스 F TaskCleanupJob FK 위반 + Puma deprecated 경고 공통 패턴: Rails 8의 Solid Stack (SolidCache, SolidQueue, SolidCable) 초기 설정 문제가 여러 프로젝트에서 반복됐다. ...

I inserted demo seed data directly into a Rails app, and all percentages showed as 0% on the screen. Server logs were clean, the data was clearly in the DB, yet the numbers would not appear. Situation This was a Rails app with a voting feature. There is a screen showing vote counts per choice, calculating percentages against total votes and displaying them with progress bars and numbers. I needed to show a demo, so I fetched real-time data from an external API and inserted it as seed data. The approach was simple: ...

I received a report that sign-up and login were completely broken. The app just repeated “An unexpected error occurred.” Symptoms Sign-up attempt -> 500 Internal Server Error Login attempt -> same 500 Health check API -> 200 OK, DB connection normal The server was alive and DB was connected, but all authentication features were dead. Investigation Process Step 1: Check Server Status SSH in and check the Rails environment. rails runner "puts Rails.env" # => production rails runner "puts User.count" # => 13 Server normal, DB connection normal, user data exists. ...

After uploading a test build of the app and running it myself, 4 things broke simultaneously. Google login failure, AI itinerary generation returning wrong results, app crash on tapping the notification button, and the popular destinations section completely empty. Here is the process of finding and fixing each cause. 1. Google SSO Fails While Apple Login Succeeds Symptoms Apple Sign-In works normally but Google Sign-In returns a 500 error. The client only shows a login failure toast. ...

Notes on integrating the DART Open API (Korea’s Financial Supervisory Service disclosure system) with a Rails backend. Implemented 5 areas: disclosure monitoring, audit opinions, governance, financial indexes, and equity reports – each step came with its own struggles. Implementation Structure Created a model and ActiveJob for each data type. Each job calls the DART API and inserts data using upsert_all – simple structure. DartCorpCodeSyncJob -> dart_companies (company master) DartDisclosureSyncJob -> dart_disclosures (disclosure list) DartMajorEventSyncJob -> dart_major_events (delisting trigger events -- DS001) DartAuditOpinionSyncJob -> dart_audit_opinions (audit opinions -- DS002/DS003) DartGovernanceSyncJob -> dart_executives / dart_major_shareholders (DS004/DS005) DartFinancialIndexSyncJob -> dart_financial_indexes (fnlttSinglAcntAll) DartEquityReportSyncJob -> dart_equity_reports (equity disclosures) Struggle 1: upsert_all + update_only + updated_at Duplication The first error to hit. ...