CAMEL-24088: camel-ftp - streamDownload treats refused RETR as success

[davsclaus]

Summary

Claude Code on behalf of davsclaus

Fixes two related bugs in FtpOperations where the streamDownload=true path never checks the FTP client's success indicators, causing silent data loss:

• retrieveFileToStreamInBody: FTPClient.retrieveFileStream() returns null when the server refuses RETR (550/450/425), but the code unconditionally set result = true. The consumer then routes the exchange with a null body and the process strategy commits — moving or deleting the remote file that was never downloaded. Fixed by setting result = is != null and only populating the body/header when the stream is available.

• releaseRetrievedFileResources: FTPClient.completePendingCommand() returns false when the transfer did not complete (server sent 426/451), but the return value was discarded. A truncated stream would be silently accepted and the commit would still run. Fixed by checking the return value and throwing GenericFileOperationFailedException on failure.

These fixes also re-enable ignoreFileNotFoundOrPermissionError for streamDownload mode — it was previously dead code because retrieved was always true.

Test plan

• New unit test FtpOperationsStreamDownloadTest with 5 test cases:
  • testRetrieveFileStreamReturnsNullOnServerError — verifies retrieveFile returns false when server refuses RETR
  • testRetrieveFileStreamSuccessReturnsTrue — verifies normal success path still works
  • testReleaseResourcesThrowsOnFailedCompletion — verifies exception on failed completePendingCommand
  • testReleaseResourcesSucceedsOnCompletedTransfer — verifies normal release path
  • testReleaseResourcesSkipsWhenNoStream — verifies no-op when no stream header present

🤖 Generated with Claude Code

[github-actions]

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[gnodet]

LGTM — important fix for silent data loss in FTP streamDownload mode.

retrieveFileToStreamInBody: FTPClient.retrieveFileStream() returns null on server refusal
(550/450/425), but the old code unconditionally set result = true (line 487 on main). This
caused the consumer to route an exchange with a null body, and the process strategy would then
commit — moving or deleting the remote file that was never actually downloaded. The fix
(result = is != null + guarded body/header) is clean and correct.

releaseRetrievedFileResources: The discarded completePendingCommand() return value meant a
truncated transfer (426/451) was silently accepted. The new check-and-throw is correct —
GenericFileOperationFailedException extends RuntimeCamelException (a RuntimeException),
so it won't be caught by the existing IOException catch clause in the same try block.

Side benefit: ignoreFileNotFoundOrPermissionError was effectively dead code for streamDownload
mode since retrieved was always true — this fix re-enables it.

Tests cover all five paths well (null stream, success stream, failed completion, success completion,
no-stream release).

Claude Code on behalf of gnodet

[github-actions]

🧪 CI tested the following changed modules:

• components/camel-ftp

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🔬 Scalpel shadow comparison — Scalpel: 12 tested, 29 compile-only — current: 12 all tested

Maveniverse Scalpel detected 41 affected modules (current approach: 12).

⚠️ Modules only in Scalpel (29)

• apache-camel
• camel-allcomponents
• camel-catalog
• camel-catalog-console
• camel-catalog-lucene
• camel-catalog-maven
• camel-catalog-suggest
• camel-componentdsl
• camel-csimple-maven-plugin
• camel-endpointdsl
• camel-endpointdsl-support
• camel-itest
• camel-jbang-core
• camel-jbang-it
• camel-jbang-main
• camel-jbang-plugin-edit
• camel-jbang-plugin-generate
• camel-jbang-plugin-kubernetes
• camel-jbang-plugin-test
• camel-kamelet-main
• camel-launcher
• camel-report-maven-plugin
• camel-route-parser
• camel-yaml-dsl
• camel-yaml-dsl-deserializers
• camel-yaml-dsl-maven-plugin
• coverage
• docs
• dummy-component

Skip-tests mode would test 12 modules (1 direct + 11 downstream), skip tests for 29 (generated code, meta-modules)

Modules Scalpel would test (12)

• camel-azure-files
• camel-ftp
• camel-jbang-mcp
• camel-jbang-plugin-mcp
• camel-jbang-plugin-route-parser
• camel-jbang-plugin-tui
• camel-jbang-plugin-validate
• camel-jsch
• camel-launcher-container
• camel-yaml-dsl-validator
• camel-yaml-dsl-validator-maven-plugin
• camel-zookeeper-master

Modules with tests skipped (29)

• apache-camel
• camel-allcomponents
• camel-catalog
• camel-catalog-console
• camel-catalog-lucene
• camel-catalog-maven
• camel-catalog-suggest
• camel-componentdsl
• camel-csimple-maven-plugin
• camel-endpointdsl
• camel-endpointdsl-support
• camel-itest
• camel-jbang-core
• camel-jbang-it
• camel-jbang-main
• camel-jbang-plugin-edit
• camel-jbang-plugin-generate
• camel-jbang-plugin-kubernetes
• camel-jbang-plugin-test
• camel-kamelet-main
• camel-launcher
• camel-report-maven-plugin
• camel-route-parser
• camel-yaml-dsl
• camel-yaml-dsl-deserializers
• camel-yaml-dsl-maven-plugin
• coverage
• docs
• dummy-component

ℹ️ Shadow mode — Scalpel observes but does not affect test execution. Learn more

All tested modules (41 modules)

• Camel :: All Components Sync point
• Camel :: Assembly
• Camel :: Azure :: Files
• Camel :: Catalog :: CSimple Maven Plugin (deprecated)
• Camel :: Catalog :: Camel Catalog
• Camel :: Catalog :: Camel Report Maven Plugin
• Camel :: Catalog :: Camel Route Parser
• Camel :: Catalog :: Console
• Camel :: Catalog :: Dummy Component
• Camel :: Catalog :: Lucene (deprecated)
• Camel :: Catalog :: Maven
• Camel :: Catalog :: Suggest
• Camel :: Component DSL
• Camel :: Coverage
• Camel :: Docs
• Camel :: Endpoint DSL
• Camel :: Endpoint DSL :: Support
• Camel :: FTP
• Camel :: Integration Tests
• Camel :: JBang :: Core
• Camel :: JBang :: Integration tests
• Camel :: JBang :: MCP
• Camel :: JBang :: Main
• Camel :: JBang :: Plugin :: Edit
• Camel :: JBang :: Plugin :: Generate
• Camel :: JBang :: Plugin :: Kubernetes
• Camel :: JBang :: Plugin :: MCP
• Camel :: JBang :: Plugin :: Route Parser
• Camel :: JBang :: Plugin :: TUI
• Camel :: JBang :: Plugin :: Testing
• Camel :: JBang :: Plugin :: Validate
• Camel :: Jsch
• Camel :: Kamelet Main
• Camel :: Launcher
• Camel :: Launcher :: Container
• Camel :: YAML DSL
• Camel :: YAML DSL :: Deserializers
• Camel :: YAML DSL :: Maven Plugins
• Camel :: YAML DSL :: Validator
• Camel :: YAML DSL :: Validator Maven Plugin
• Camel :: Zookeeper Master

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