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feat: add --redact/--compress/--open for heap-dump, jstall bundle, and JRE-only fallback - #56
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- Embeds hprof-redact binaries (linux/amd64, linux/arm64, darwin/arm64, windows/amd64) via //go:embed; extracted to ~/.cache/cf-java-plugin/ on first use (SHA8-keyed, reused on subsequent runs). - --compress: passes gz=1 to jmap (JDK 17+) to compress the dump on the remote container before transfer, saving bandwidth. jvmmon path falls back to post-creation gzip on the container. Output is .hprof.gz. - --redact: pipes the downloaded dump through hprof-redact (lean mode: zeros primitive arrays only). Output is -redacted.hprof or -redacted.hprof.gz when --compress is also set. - --redact-complete: like --redact but zeros all primitive values (instance scalar fields + CLASS_DUMP statics) via two-pass redaction. - --compress and --redact can be combined: compress on remote to reduce transfer, redact locally (hprof-redact reads .hprof.gz natively). - Adds FindHeapDumpGzFile to utils for locating *.hprof.gz on the container (jvmmon+compress path). - Extracts osWindows and cmdHeapDump constants to satisfy goconst.
- hprof-analyzer release.yml: add aarch64-pc-windows-msvc target on windows-11-arm runner; compile-all includes GOOS=windows GOARCH=arm64 - redact.go: embed dist/hprof-redact-windows-arm64.exe (stub until v0.3.1 ships); add windows/arm64 case; guard against 0-byte stubs - cfutils.go: add CopyOverCatGunzip (io.Pipe + compress/gzip for transparent streaming decompression) and ProbeRemoteFileGzip (checks gzip magic bytes 1f8b via SSH) - cf_cli_java_plugin.go: heap-dump SSHCommand now uses shell-level gz probe (jmap -h | grep gz) so jmap auto-uses gz=1 on JDK 17+; Go post-command probes the remote file magic bytes to decide: - remote gz + no --compress → CopyOverCatGunzip, save as .hprof - remote gz + --compress → CopyOverCat, save as .hprof.gz - not gz + --compress → warn JDK 17+ required, save uncompressed Removes @JMAP_GZ Go expansion (replaced by shell probe); keeps @COMPRESS_FLAG for jvmmon path
- appInstanceIndexSet: simonleung8/flags IsSet() returns true for any registered flag whose non-zero default was set at init time, making it impossible to distinguish user-provided from default. Compare against known default (-1) instead. - CheckRequiredTools wrapped in !options.DryRun guard so dry-run works without CF login or SSH access. - var err declaration hoisted before GenerateFiles block (needed after CheckRequiredTools was scoped inside the if block).
…-dump - Feature list in intro - Examples: --redact, --redact-complete, --compress, combined usage - New "Heap Dump Privacy" subsection: redaction modes table, what is preserved, file naming, supported platforms - New "Compressed Transfer" subsection: JDK 17+ requirement, fallback behaviour, transparent gz transfer without --compress - CHANGELOG [Unreleased]: all four new behaviours
- Use context.WithTimeout(context.Background(), 5s) for srv.Shutdown instead of the request context (which may already be canceled); suppress contextcheck lint with explanation since this is intentional - Add empty title arg to Windows `cmd /c start` to avoid URL being interpreted as the window title - Replace non-blocking done-channel check in test with a 2s timeout select to avoid a false-pass race condition
…eakage and restrict access to single file
… in serveFileOnce
…s only affects local file format
golangci-lint typecheck fails when the dist/ hprof-redact binaries are missing (go:embed pattern not satisfied). Add a download step mirroring build.py, placed after the existing jstall download and before lint.
The previous attempt tried to curl the binaries directly, but they are packed inside tar.gz/zip archives. Add --deps-only flag to build.py to run only the download+extraction step (no go build), and use it in the PR validation workflow before golangci-lint.
dbriemann
reviewed
Sep 18, 2026
ansteiner
requested changes
Sep 18, 2026
cf install-plugin rejects binaries without the .exe extension on Windows, causing "temp/...exe doesn't exist" errors. build.py now outputs cf-cli-java-plugin-windows-amd64.exe, README and release body URLs updated accordingly, and the CI smoke-test asserts the extension before installing.
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There is now Windows support (tested with amd64 Cygwin and PowerShell) for the jstall-related features. I tested these features manually. |
- WorkloadApp: read PORT env var instead of hardcoding 8080 - jdk21/jdk25 manifests: bump memory to 512M and cap ReservedCodeCacheSize=64M so the memory calculator fits within limits - Add run-on-all.sh: run any cf java command across all (or filtered) apps in parallel, group output by similarity, --keep-tmp support
Exit code 10 from jstall means "ran successfully but found a warning condition" (e.g. JVM older than ~4 months). The plugin was surfacing this as an error: "jstall execution failed: exit status 10" Treat it as success — the warning is already printed to stdout by jstall. Also adds JSTALL_LOCAL=/path/to/jar make variable so developers can test against a locally built jstall JAR without publishing to GitHub: JSTALL_LOCAL=../jstall/target/jstall.jar make install
… JDK 11 Two causes of the crash: 1. Memory: JDK 11 default ReservedCodeCacheSize=240M exhausted 256M container. Bump to 512M and cap ReservedCodeCacheSize=64M (same fix as jdk21/jdk25). 2. The sap_java_buildpack_jakarta injects a logging-level-change-agent JAR compiled for Java 17+ (class file version 61.0), which fails with UnsupportedClassVersionError on Java 11 (max class version 55.0). Exclude LoggingLevelChangeAgent from the frameworks list via JBP_CONFIG_COMPONENTS.
…-all.sh arg order jdk11 and jdk17 were crashing at startup: the CF java-buildpack memory calculator defaults ReservedCodeCacheSize=240M on JDK 11/17, exceeding the 256M limit. Bump to 512M and cap to 64M (same fix applied earlier to jdk21/jdk25/sapmachine11). Also fix run-on-all.sh: the CF CLI syntax is 'cf java SUBCOMMAND APP [options]', but the script was calling 'cf java APP SUBCOMMAND'. Insert the app name after CF_ARGS[0] (the subcommand) so e.g. './run-on-all.sh -- asprof-status' works.
…mp jstall to 0.8.0
Add AttachSocketNCHelper shell function (nc_jcmd) that communicates with
the JVM via HotSpot attach socket, enabling diagnostics on JRE-only
containers where jcmd/jstack are absent.
- thread-dump: try jstack → jvmmon → nc_jcmd Thread.print (with clear
error if all three are absent)
- vm-info: try jcmd VM.info → nc_jcmd VM.info (removed RequiredTools hard-fail)
- vm-version: try jcmd VM.version → nc_jcmd VM.version
The nc_jcmd helper handles attach-socket creation on demand (SIGQUIT
handshake) and resolves macOS $TMPDIR trailing-slash via ${TMPDIR%/}.
Requires netcat-openbsd or nmap-ncat on the container.
heap-dump: fall back to GC.heap_dump via nc_jcmd when jmap/jvmmon absent. Verifies file exists after write; clear error if nc also unavailable. jcmd: remove RequiredTools hard-fail; try jcmd binary first, fall back to nc_jcmd for arbitrary jcmd commands on JRE-only containers. @Args is split via "set -- @Args" so nc_jcmd receives command + args as separate positional parameters. nc_jcmd: propagate non-zero return codes from attach protocol as errors instead of silently returning empty output. Add nc_available() helper to avoid repeating the nc -h probe inline.
HotSpot's attach protocol expects the entire command line (command name + space-separated args) as a single NUL-terminated field: printf '1\0jcmd\0GC.heap_dump /tmp/out.hprof\0\0\0' It then splits that field on spaces to extract command and arguments. The previous format sent command and each arg as separate NUL-delimited fields, which the JVM ignored — causing "filename is mandatory" for GC.heap_dump and silent no-ops for any multi-arg command. Simplify nc_jcmd to: nc_jcmd PID CMDLINE... where "$*" after shift builds the full command line string naturally.
…ly jstall note, specific SSH error detail
parttimenerd
changed the title
- fix: decompress gzip stream before passing to hprof-redact when remote jmap used gz=1 (JDK 17+); previously hprof-redact received raw gzip bytes and would corrupt or reject the file (fixes --redact on JDK 17+ containers) - fix: single-quote app name in jstall --ssh fallback path to handle app names with spaces or shell metacharacters - fix: remove WriteTimeout from one-shot heap dump HTTP server; a 30s deadline killed large (>3GB) dump transfers to the browser mid-stream - warn: print a warning when --redact/--redact-complete/--compress/--open/ --open-url are passed to non-heap-dump commands (previously silently ignored) - refactor: replace inline nc -U checks in thread-dump/vm-info/vm-version shell snippets with nc_available() for consistency with heap-dump/jcmd
- jvmmon path: write setHeapDumpOnDemandPath.sh into @fspath (not the current directory) and remove it after use; previously the script was left behind on the container after every jvmmon heap dump - redact: remove pre-write-access check (create+remove before hprof-redact runs); MkdirAll already covers the directory case and any write failure will surface naturally from hprof-redact itself without the TOCTOU window
…uffer The 192 KB file fit entirely in the kernel TCP send buffer, so io.Copy completed successfully even after the client disconnected — spuriously triggering server shutdown and failing the test. Also updates dist/jstall-minimal.jar with the vm-vitals two-section fix (recent samples + extremes capped at max(10, topN)).
Update dist/jstall-minimal.jar to v0.8.2 (vm-vitals parser rewrite, Trends + Observations sections, heap-comm/meta-comm duplicate-column fix). Update CHANGELOG to document the new vm-vitals features. Add two unit tests covering the app/command swap-detection logic.
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Summary
New heap-dump flags
--redact: zeros primitive arrays (byte[],char[], etc.) before saving (lean redaction mode). Uses the bundled hprof-redact binary. Supported on Linux (amd64/arm64), macOS (Apple Silicon), Windows (amd64/arm64).--redact-complete: zeros all primitive arrays and individual primitive fields (complete redaction, maximum privacy). Mutually exclusive with--redact.--compress: saves the dump as.hprof.gzinstead of decompressing after transfer (requires JDK 17+ on container).jmap gz=1to reduce SSH transfer size, decompressing on the fly.--compresskeeps the file compressed locally.--open: after downloading, spins up a temporary single-serve local HTTP server and opens hprof-analyzer in the browser with the dump pre-loaded. Server shuts down automatically after the file is fetched once.--open-url <URL>: override the hprof-analyzer base URL (e.g. a locally running instance). Implies--open.Bundled jstall (JVM inspection)
cf java jstall APP_NAME(or thestatus/record-statusshortcuts). Requires Java 17+ locally.status(thread analysis, metaspace, GC, compiler queue),record-status(repeated sampling),flame-graph,heap-info. All jstall subcommands available via--args.JRE-only container support
heap-dump,thread-dump,vm-info,vm-version,jcmd, and all jstall-based commands now work on containers without JDK tools (jmap,jstack,jcmd) by falling back to the HotSpot attach socket vianc -U.netcat-openbsdornmap-ncaton the container. Supports JDK 9–25 on Linux and macOS.Windows fixes
cf install-plugin <URL>now works on Windows: Windows binary released ascf-cli-java-plugin-windows-amd64.exe(with.exe). CF CLI previously rejected the temp file without the extension.cf java statusand other jstall-based commands now work on Windows: JVM propertyjdk.lang.Process.allowAmbiguousCommands=falseensures embedded quotes in remote shell payloads are correctly escaped viaProcessBuilder.UX improvements
cf java my-app heap-dump): suggests the corrected command if the first argument matches a known app.Maintenance
upload-artifactto v7,download-artifactto v8.darwin/amd64dropped.Security notes (
--open)127.0.0.1only (loopback, not reachable from network)io.Copydirectly (nothttp.ServeFile) to prevent path traversal