BC-064A — Projection / Application Boundary Audit¶

Status: HISTORICAL For the current architecture, see: ./dependances.md, ../projections/overview.md, ../frontend/projections.md.

Status¶

Audit only.

No functional change, no class move, no namespace rename, no runtime sync.

Scope¶

src/Domain/
src/Contracts/
src/Application/
src/Projection/
src/ReadService/
src/Adapter/
src/Infrastructure/
plugin frontend/application/runtime entrypoints that compose these classes

Normative target¶

Source of truth used for this audit:

docs/architecture/boundary-architecture.md
docs/architecture/dependances.md
docs/architecture/principes.md
docs/architecture/application-infrastructure-contract.md

Target direction retained for BC-064:

Layer	May depend on
Domain	internal helpers, internal contracts
Contracts	no implementation detail
Application	Domain, Knowledge, Contracts
Projection	Domain, Contracts, pure projection DTOs
ReadService	Domain, Contracts, Vertical Modules, Projection DTOs
Infrastructure	Contracts
Adapter	Contracts, Infrastructure, legacy tech details

Practical corollaries for this audit:

Projection must not depend on Application orchestration DTOs.
ReadService must not instantiate concrete adapters/shims by default.
Infrastructure must not depend on Application-owned ports/DTOs.
Contracts should not be forced to import specialized Projection DTOs when a more stable contract shape is expected.

Observed dependency signals¶

Coarse static scan on the audited tree:

Edge	Count	Observation
`Projection -> Application`	1	real violation
`ReadService -> Adapter`	4	real boundary drift
`Infrastructure -> Application`	3	real boundary drift
`Contracts -> Projection`	8	stable-contract fragility

Namespace graph¶

Domain ───────────────────────────────► Domain
Contracts ────────────────────────────► Projection      (fragile)
Application ──────────────────────────► Domain
Projection ───────────────────────────► Application     (forbidden)
ReadService ──────────────────────────► Contracts
ReadService ──────────────────────────► Projection
ReadService ──────────────────────────► Adapter         (forbidden)
Adapter ──────────────────────────────► Contracts
Adapter ──────────────────────────────► Projection
Infrastructure ───────────────────────► Contracts       (target)
Infrastructure ───────────────────────► Application     (forbidden)
Plugin frontend ──────────────────────► ReadService / Contracts / Projection
Adapter legacy read ──────────────────► WordPress globals / plugin helpers / SQL

Detailed findings¶

BA-PA-001 — Projection depends on Application¶

Priority: P0
Type: real boundary violation
Edge: Projection -> Application
File: src/Projection/Offer/OfferProjectionBuilder.php
Proof: imports CMonChoix\Platform\Application\Enrichment\EnrichedStageEntry

Observed shape:

OfferProjectionBuilder::fromEnrichedStageEntry(EnrichedStageEntry $entry): array
OfferProjectionBuilder::fromRecord(EnrichedStageEntry $entry, array $record, int $index): OfferProjection

Why this is invalid:

EnrichedStageEntry is an Application orchestration DTO.
Projection becomes aware of a use-case transport shape instead of a stable projection input.
This inverts the intended direction: Application may prepare data for Projection, but Projection must not import Application.

Blast radius:

src/Application/Enrichment/EnrichedStageEntry.php
src/Application/DomainCore/BuildCandidateFromEnrichedStageEntry.php
tests around projection building and enrichment

Recommended BC:

BC-064B

Status after BC-064B:

closed by introducing CMonChoix\Platform\Contracts\Projection\OfferProjectionSource
EnrichedStageEntry now implements the neutral contract
OfferProjectionBuilder no longer imports Application\Enrichment\EnrichedStageEntry

BA-RA-001 — ReadService instantiates concrete legacy adapters¶

Priority: P1
Type: real boundary violation
Edge: ReadService -> Adapter
File: src/ReadService/ProductModels/ProductModelsFrontendReadService.php

Proof:

default constructor values instantiate:
new LegacyCatalogItemProjectionAdapter()
new LegacyFacetProjectionAdapter()
new LegacyProductProjectionAdapter()

Why this is invalid:

ReadService should stay on stable contracts and projection DTOs.
Concrete legacy adaptation belongs to the adapter composition boundary, not inside the read service itself.
This makes the read service hard to reuse outside the legacy WordPress rendering path.

Blast radius:

plugins/ccx-feeds-industrial/includes/frontend/product-models.php
runtime mirror
tests/Runtime/ProductModelsProjectionBuilderTest.php
tests/Frontend/ProductModelsCatalogRoutingTest.php

Recommended BC:

BC-064C

Status after BC-064C:

closed by injecting CatalogItemProjectionMapper, FacetProjectionMapper and ProductViewProjectionMapper
concrete legacy adapter composition moved to WordPress frontend wrappers

BA-RA-002 — ReadService depends on array shim¶

Priority: P2
Type: controlled transitional coupling
Edge: ReadService -> Adapter
File: src/ReadService/Frontend/PublicNavigationReadService.php

Proof:

constructor default value: new FrontendProjectionArrayShim()

Why this is fragile:

the shim itself is acceptable as an explicit compatibility adapter;
the fragile point is its placement inside ReadService rather than at the outer adapter/rendering boundary.

Why this is lower priority than BA-RA-001:

it remains read-only;
it converts projection DTOs to a legacy array shape;
it does not pull SQL or WordPress execution into ReadService.

Recommended BC:

BC-064C

Status after BC-064C:

closed by making PublicNavigationReadService return NavigationProjection
FrontendProjectionArrayShim remains confined to the WordPress wrapper

BA-IA-001 — Infrastructure depends on Application-owned feed ports¶

Priority: P1
Type: real boundary violation
Edge: Infrastructure -> Application

Files:

src/Infrastructure/Feed/InMemoryMerchantFeedPublicationInputReader.php
src/Infrastructure/Feed/InMemoryRawMerchantFeedBatchWriter.php

Proof:

imports from CMonChoix\Platform\Application\Feed\...
implements:
MerchantFeedPublicationInputReader
RawMerchantFeedBatchWriter
returns MerchantFeedPublicationInput

Why this is invalid:

normative docs state Infrastructure may depend on Contracts.
here the ports and one crossing DTO are owned by Application.
Infrastructure therefore imports an application boundary instead of a stable contract boundary.

Recommended BC:

BC-064D

BA-CP-001 — Contracts import specialized Projection DTOs¶

Priority: P1
Type: contract fragility
Edge: Contracts -> Projection

Files:

src/Contracts/Projection/CanonicalProductProjectionReader.php
src/Contracts/Projection/CatalogProjectionReader.php
src/Contracts/Projection/NavigationProjectionReader.php
src/Contracts/Projection/ProductProjectionReader.php

Proof:

these interfaces import DTOs from src/Projection/...

Why this is fragile:

docs describe Contracts as independent and free of implementation detail;
current interfaces are stable enough for runtime use, but they are not neutral contracts;
they couple the collaboration boundary to one specialized projection namespace.

Assessment:

not the first fix to land;
but this is the structural reason later layers cannot fully decouple cleanly.

Recommended BC:

BC-064D or BC-064F depending on desired extraction strategy

BA-AL-001 — Legacy namespace island remains inside `src/Application`¶

Priority: P2
Type: architectural debt / coexistence risk

Proof:

multiple files still use namespace CMonChoix\Application\...
examples:
src/Application/Projection/ProjectionCatalogWiring.php
src/Application/Contracts/EventStoreInterface.php
src/Application/Contracts/QueueInterface.php
src/Application/Catalog/MerchantNormalizer.php
some src/Infrastructure/... classes import these legacy namespaces

Why this matters:

the tree mixes CMonChoix\Platform\... and legacy CMonChoix\Application\...
dependency audits become harder because physical location and logical layer no longer align

Assessment:

not an immediate runtime regression;
but it amplifies BC-064 remediation cost and hides future boundary leaks.

Recommended BC:

BC-064E

BA-AL-002 — Application bridge still uses `require_once`¶

Priority: P2
Type: transitional compatibility bridge
File: src/Application/Normalization/NormalizationFacade.php

Proof:

require_once __DIR__ . '/../Catalog/MerchantNormalizer.php';
imports legacy namespace CMonChoix\Application\Catalog\MerchantNormalizer

Why this is fragile:

Application keeps a file-level legacy bootstrap bridge;
this is not a business bug, but it prevents a clean Application/Contracts boundary story.

Recommended BC:

BC-064E

Interfaces and ports inventory¶

Stable contracts currently under `src/Contracts`¶

File	Role
`src/Contracts/Projection/CanonicalProductProjectionReader.php`	projection read port
`src/Contracts/Projection/CatalogProjectionReader.php`	projection read port
`src/Contracts/Projection/NavigationProjectionReader.php`	projection read port
`src/Contracts/Projection/ProductProjectionReader.php`	projection read port

Ports still owned by `src/Application`¶

File	Current role	Expected direction issue
`src/Application/Feed/MerchantFeedPublicationInputReader.php`	input port	consumed by Infrastructure
`src/Application/Feed/RawMerchantFeedBatchWriter.php`	output port	consumed by Infrastructure
`src/Application/Contracts/EventStoreInterface.php`	legacy port	namespace island
`src/Application/Contracts/QueueInterface.php`	legacy port	namespace island
`src/Application/Shared/Event/EventDispatcherInterface.php`	legacy/shared port	namespace island

DTO inventory relevant to the boundary¶

File	Role	Observation
`src/Application/Enrichment/EnrichedStageEntry.php`	orchestration DTO	wrongly imported by Projection
`src/Application/Normalization/NormalizedStageEntry.php`	orchestration DTO	stays in Application for now
`src/Application/Feed/MerchantFeedPublicationInput.php`	feed crossing DTO	better placed with boundary contracts
`src/Application/Feed/ReceiveMerchantFeedResult.php`	use-case result DTO	acceptable in Application
`src/Projection/...` DTOs	read model DTOs	acceptable in Projection

Concrete instantiations found in ReadService / Application¶

File	Instantiation / bridge	Assessment
`src/ReadService/ProductModels/ProductModelsFrontendReadService.php`	3 concrete legacy adapters in constructor defaults	forbidden drift
`src/ReadService/Frontend/PublicNavigationReadService.php`	`new FrontendProjectionArrayShim()`	transitional drift
`src/Application/Normalization/NormalizationFacade.php`	`require_once` legacy bridge	transitional drift
`src/Application/M24/Daemon/WorkerDaemon.php`	`function_exists('pcntl_*')`	acceptable executable concern

No direct $wpdb usage was found in src/Application or src/ReadService.

Legacy shim inventory¶

File	Purpose	Audit result
`src/Adapter/Legacy/Projection/FrontendProjectionArrayShim.php`	DTO -> legacy array translation	acceptable as adapter, not inside ReadService
`src/Adapter/Legacy/Projection/LegacyCatalogItemProjectionAdapter.php`	legacy item mapping	acceptable adapter
`src/Adapter/Legacy/Projection/LegacyFacetProjectionAdapter.php`	legacy facet mapping	acceptable adapter
`src/Adapter/Legacy/Projection/LegacyNavigationProjectionAdapter.php`	legacy nav mapping	acceptable adapter
`src/Adapter/Legacy/Projection/LegacyProductProjectionAdapter.php`	legacy product mapping	acceptable adapter

Builders audit¶

File	Result
`src/Projection/Offer/OfferProjectionBuilder.php`	forbidden `Projection -> Application` dependency
`src/Domain/Product/Cluster/ProductClusterBuilder.php`	domain-local builder, no BC-064A issue found
`src/Application/Projection/CatalogProjectionWriter.php`	application write-side service, outside the primary projection-read leak found here

Cycles and near-cycles¶

No direct PHP namespace cycle was proven by this audit.

Two structural near-cycles were proven:

Application DTO -> Projection builder, while Contracts already point to Projection DTOs.
ReadService -> Adapter, while plugin frontend already composes the same read path from the outside.

These patterns are enough to make future cycles easy to introduce even when the current code still runs.

`src` ↔ plugin legacy coupling¶

Acceptable direction¶

Plugin/frontend code composes Platform classes:

catalog router uses CatalogProjectionReader and CatalogQuery
product canonical repository uses CanonicalProductReadService
public navigation uses PublicNavigationReadService
product models frontend uses ProductModelsFrontendReadService

This direction is expected: WordPress adapter -> Platform classes.

Controlled legacy coupling inside adapters¶

The following adapter readers still use WordPress/plugin helpers and SQL:

src/Adapter/Legacy/Read/SqlNavigationProjectionReader.php
src/Adapter/Legacy/Read/SqlLegacyCatalogProjectionReader.php
src/Adapter/Legacy/Read/SqlCanonicalProductProjectionReader.php

Observed concrete couplings:

$GLOBALS['wpdb']
sanitize_title()
remove_accents()
ccx_feeds_table()
ccx_feeds_db_has_table()
ccx_navigation_taxonomy_*
ccx_catalog_nav_cache_*

Assessment:

acceptable in Adapter layer;
forbidden if similar calls move upward into ReadService, Projection or Application.

Existing test coverage gap¶

Current architecture tests do not fully guard BC-064 concerns:

tests/Architecture/ProjectionBoundaryTest.php forbids WordPress/runtime/frontend/SQL leaks in Projection, but does not forbid Projection -> Application;
tests/Architecture/FrontendReadServiceBoundaryTest.php characterizes plugin/frontend delegation, but does not forbid ReadService -> Adapter.

Priority matrix¶

ID	Cause	Layer	Severity	Classification	Action
BA-PA-001	Projection imports orchestration DTO	Projection/Application	P0	real violation	extract neutral projection input
BA-RA-001	ReadService instantiates legacy adapters	ReadService/Adapter	P1	real violation	move adapter wiring outward
BA-RA-002	ReadService owns array shim	ReadService/Adapter	P2	transitional drift	move shim outward after BA-RA-001
BA-IA-001	Infrastructure imports Application feed ports	Infrastructure/Application	P1	real violation	move feed ports/DTO contract boundary
BA-CP-001	Contracts import Projection DTOs	Contracts/Projection	P1	structural fragility	introduce neutral contracts progressively
BA-AL-001	legacy namespace island under `src/Application`	Application	P2	legacy coexistence debt	isolate/retire
BA-AL-002	`require_once` bridge in Application	Application	P2	transitional compatibility	replace after namespace isolation

Proposed sequencing¶

BC-064B — Projection input neutralization¶

remove Projection -> Application
replace EnrichedStageEntry dependency in OfferProjectionBuilder
add architecture gate forbidding use CMonChoix\\Platform\\Application\\ inside src/Projection

BC-064C — ReadService adapter extraction¶

externalize concrete adapter/shim composition from ReadService
keep behavior unchanged for WordPress/frontend runtime
add gate forbidding new .*Adapter() and new .*Shim() in src/ReadService

BC-064D — Contract boundary extraction¶

move feed ports and crossing DTOs to stable contracts
decide whether projection reader contracts stay in Contracts/Projection or become neutral read contracts returning neutral DTOs

BC-064E — Legacy namespace island isolation¶

isolate remaining CMonChoix\Application\... subtree
remove file-level bridges like require_once from NormalizationFacade

BC-064F — Final certification¶

add architecture tests for:
no Projection -> Application
no ReadService -> Adapter
no Infrastructure -> Application
optionally, controlled Contracts -> Projection policy

Risks if left unchanged¶

Projection remains coupled to one use-case orchestration path.
Read services remain bound to WordPress legacy rendering concerns.
Infrastructure contracts remain hard to reuse or replace.
future extractions will cost more because logical layer and physical tree diverge.

Rollback¶

Audit-only rollback is trivial:

remove this document.

No SQL rollback. No runtime rollback. No sync rollback.

BC-064A — Projection / Application Boundary Audit¶

Status¶

Scope¶

Normative target¶

Observed dependency signals¶

Namespace graph¶

Detailed findings¶

BA-PA-001 — Projection depends on Application¶

BA-RA-001 — ReadService instantiates concrete legacy adapters¶

BA-RA-002 — ReadService depends on array shim¶

BA-IA-001 — Infrastructure depends on Application-owned feed ports¶

BA-CP-001 — Contracts import specialized Projection DTOs¶

BA-AL-001 — Legacy namespace island remains inside src/Application¶

BA-AL-002 — Application bridge still uses require_once¶

Interfaces and ports inventory¶

Stable contracts currently under src/Contracts¶

Ports still owned by src/Application¶

DTO inventory relevant to the boundary¶

Concrete instantiations found in ReadService / Application¶

Legacy shim inventory¶

Builders audit¶

Cycles and near-cycles¶

src ↔ plugin legacy coupling¶

Acceptable direction¶

Controlled legacy coupling inside adapters¶

Existing test coverage gap¶

Priority matrix¶

Proposed sequencing¶

BC-064B — Projection input neutralization¶

BC-064C — ReadService adapter extraction¶

BC-064D — Contract boundary extraction¶

BC-064E — Legacy namespace island isolation¶

BC-064F — Final certification¶

Risks if left unchanged¶

Rollback¶

BA-AL-001 — Legacy namespace island remains inside `src/Application`¶

BA-AL-002 — Application bridge still uses `require_once`¶

Stable contracts currently under `src/Contracts`¶

Ports still owned by `src/Application`¶

`src` ↔ plugin legacy coupling¶