adityamparikh opened a new pull request, #189:
URL: https://github.com/apache/solr-mcp/pull/189
## The bug
`logback-spring.xml` is never loaded. HTTP mode therefore runs with **no
appenders at all** — no console logging and no OTLP log export — and any
startup failure exits 1 printing nothing but the Spring banner.
Reproduce on `main`:
```bash
PROFILES=http ./gradlew bootRun
```
Output is the banner, four JVM `Unsafe` warnings, then:
```
> Task :bootRun FAILED
> Process 'command '.../bin/java'' finished with non-zero exit value 1
```
No stack trace, no failure analyzer, no `APPLICATION FAILED TO START`. Force
the config and the real error appears:
```bash
LOGGING_CONFIG=classpath:logback-spring.xml PROFILES=http ./gradlew bootRun
# 0 log lines before -> 34 after, including:
# The following 1 profile is active: "http"
```
## Root cause
Spring Boot's `AbstractLoggingSystem.initializeWithConventions()` checks the
**standard** Logback locations first (`logback-test.xml`, `logback.xml`, …). If
it finds one and `logging.file.name` is unset, it calls `reinitialize()` and
**returns early** — `logback-spring.xml` is never consulted.
This repo shipped both files. `logback.xml` contains only a
`NopStatusListener` and no appenders, so it won a race it was never meant to
enter, and the `<springProfile>` blocks holding CONSOLE and OTEL silently
disappeared.
```
LoggerFactory first touch
└─► logback auto-config picks logback.xml (statusListener only, no
appenders)
Spring Boot ApplicationEnvironmentPreparedEvent
└─► AbstractLoggingSystem.initializeWithConventions()
├─ getSelfInitializationConfig() -> logback.xml FOUND
├─ reinitialize() <-- reloads logback.xml
└─ return <-- logback-spring.xml never loaded
CONSOLE + OTEL never exist
```
This is Boot's documented rule, not an edge case:
> We recommend that you use the `-spring` variant for your logging
configuration (for example, `logback-spring.xml` rather than `logback.xml`). If
you use standard configuration locations, Spring cannot completely control log
initialization.
> [Logback extensions] cannot be used in the standard `logback.xml` file
because it is loaded too early.
## The fix
Delete `logback.xml`; `logback-spring.xml` becomes the single logging
configuration. The `NopStatusListener` was **already declared** in
`logback-spring.xml`, so deleting the other file activates the suppression
rather than removing it.
Also in this PR:
- Use Boot's own `console-appender.xml` instead of a hand-rolled
`ConsoleAppender`, so `logging.pattern.console` / `logging.charset.console` /
`logging.threshold.console` behave as in a stock Boot app. The hand-rolled
encoder's fallback was already dead code: `defaults.xml` defines
`CONSOLE_LOG_PATTERN`, so `${CONSOLE_LOG_PATTERN:-…}` always resolved to Boot's
pattern — the rendered format is unchanged.
- Register `logback-spring.xml` (not `logback.xml`) as a native-image
resource in `SolrNativeHints`.
- Add `LoggingConfigurationTest`, which fails the build if any
standard-location Logback file reappears.
- Correct the Logging Architecture section of `AGENTS.md`, which claimed
*"`logback-spring.xml` — Loaded by Spring Boot, overrides `logback.xml`."* That
was the intent, not the behaviour.
## Why removing logback.xml is safe for STDIO
`logback.xml` was justified as *"Required for native image where logback
falls through to `BasicConfigurator`."* The STDIO transport's stdout
cleanliness is directly covered by `McpClientStdioIntegrationTest`, which
spawns the real `java -jar` and runs the full MCP JSON-RPC workflow — a single
stray stdout line fails it.
## Verification
| Check | Result |
|---|---|
| `./gradlew build` | ✅ 391 tests, **0 failures**, 7 skipped |
| `McpClientStdioIntegrationTest` (real jar, MCP over stdout) | ✅ 39/39, 0
skipped |
| `LoggingConfigurationTest` | ✅ 2/2 (fails on `main`) |
| `PROFILES=http ./gradlew bootRun`, no override | ✅ 34 log lines (0 before)
|
| `./gradlew nativeTest -Pnative` | ⏳ running locally; will report |
Reviewers: the native path is the one place I have not yet confirmed green —
happy to hold merge on that result.
🤖 Generated with [Claude Code](https://claude.com/claude-code)
https://claude.ai/code/session_01Bbs8w62uwcx12ZE8E2xg8P
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