CAMEL-23579: camel-pdf - align Exchange header constant names with Camel naming convention

[oscerd]

Summary

Renames the Exchange header string values in PdfHeaderConstants from non-Camel
prefixed values (protection-policy, pdf-document, decryption-material,
files-to-merge) to CamelPdf<Name>, following the convention used across
the rest of the Camel component catalog and matching the pattern established
in CAMEL-23526 (camel-cxf), CAMEL-23522 (camel-mail), CAMEL-23461
(camel-aws-bedrock), CAMEL-23532 (camel-vertx-websocket /
camel-atmosphere-websocket / camel-iggy), and CAMEL-23576 (camel-jira).

The Java field names (PROTECTION_POLICY_HEADER_NAME, PDF_DOCUMENT_HEADER_NAME,
DECRYPTION_MATERIAL_HEADER_NAME, FILES_TO_MERGE_HEADER_NAME) are unchanged
so routes referencing the constants symbolically continue to work; routes
using the literal string values must be updated (documented in the 4.21
upgrade guide).

Why it matters

The previous header names (protection-policy, pdf-document,
decryption-material, files-to-merge) sit outside the Camel* namespace
that DefaultHeaderFilterStrategy filters at transport boundaries. The
pdf-document and decryption-material headers carry security-sensitive
PDFBox objects (PDDocument, DecryptionMaterial); protection-policy
carries the encryption settings used when writing the PDF. Untrusted producers
upstream of a PDF processing route could previously inject these headers
without them being filtered, allowing an attacker who controls a transport
hop (HTTP, JMS, etc.) to swap in their own PDDocument or bypass encryption
expectations. Aligning the values with the Camel* namespace lets the
default header filter do its job.

Generated artifacts

• components/camel-pdf/.../pdf.json (component catalog)
• catalog/camel-catalog/.../components/pdf.json (catalog mirror)
• dsl/camel-endpointdsl/.../PdfEndpointBuilderFactory.java — DSL header
  accessors renamed (protectionPolicy() → pdfProtectionPolicy(),
  decryptionMaterial() → pdfDecryptionMaterial(),
  filesToMerge() → pdfFilesToMerge(); pdfDocument() keeps its name
  but returns the new value CamelPdfDocument)

Backports

camel-pdf exists on camel-4.18.x (identical source) and camel-4.14.x
(same constant values, slightly older Javadoc style). Backports are
straightforward and will be filed as follow-up PRs.

Test plan

• mvn test in components/camel-pdf — 10 tests pass
• Build the module, catalog module and camel-endpointdsl from a clean
  state, verify only camel-pdf regen artifacts appear in git status
• Tests use symbolic constant references, so no test changes needed
• Upgrade guide entry added under === camel-pdf

Tracker: CAMEL-23577

Reported by Claude Code on behalf of Andrea Cosentino

[github-actions]

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[github-actions]

🧪 CI tested the following changed modules:

• catalog/camel-catalog
• components/camel-pdf
• docs
• dsl/camel-endpointdsl

All tested modules (10 modules)

• Camel :: Catalog :: Camel Catalog
• Camel :: Endpoint DSL
• Camel :: JBang :: MCP
• Camel :: JBang :: Plugin :: Route Parser
• Camel :: JBang :: Plugin :: TUI
• Camel :: JBang :: Plugin :: Validate
• Camel :: Launcher :: Container
• Camel :: PDF
• Camel :: YAML DSL :: Validator
• Camel :: YAML DSL :: Validator Maven Plugin

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⚙️ View full build and test results

[gnodet]

Looks good — all 4 header values correctly renamed to CamelPdf* PascalCase convention. Upgrade guide entry is thorough with old-to-new mapping and Endpoint DSL accessor renames.

Minor: the PR title says CAMEL-23579 but the body says "Tracker: CAMEL-23577" — might want to align those.

Claude Code on behalf of Guillaume Nodet