bcquality/microsoft/knowledge/security/do-not-hardcode-environment-specific-guids.md
Jesper Schulz-Wedde e570d6113f Extract 55 knowledge articles from BC review-agent prompt
Adds 55 articles (plus 76 code samples) spanning four new domains and
two existing domains, extracted from the internal Business Central
review-agent prompt. Content was filtered against BCQuality's
remedial-knowledge premise: each article encodes BC-specific behaviour,
a CodeCop rule, a platform API semantic, or an anti-false-positive
guideline that a capable LLM would otherwise get wrong.

New domains:
- privacy (11 articles): DataClassification inheritance semantics, the
  StrSubstNo-defeats-Error-telemetry-classification pitfall, Privacy
  Notice consent for outgoing requests, anti-false-positives for pages
  and in-memory data.
- upgrade (11 articles): upgrade-codeunit structure, upgrade-tag
  lifecycle and registration, protected DB reads, DataTransfer for
  large datasets, InitValue semantics, enum-ordinal preservation,
  obsolete-workflow, first-install detection.
- ui (9 articles): caption capitalization by phrase type, tooltip voice,
  teaching-tip vs tooltip, tour-tip conventions, character limits,
  banned terms, ampersand handling, title punctuation.
- style (11 articles): label-suffix convention, API page naming,
  temporary-variable prefix, label properties (Comment/Locked), named
  invocations, FieldCaption in user messages, OptionCaption pairing,
  Error-parameter passing, `this` keyword, required parentheses, file
  naming.

Gaps in existing domains:
- performance (11 articles): production-scale table catalog (no row
  counts, per internal-data concern), anti-false-positive for bounded
  tables, guard-before-Get ordering, redundant-Get-in-OnAfterGetRecord,
  LockTable in read-only helpers, combined ModifyAll passes, writes in
  OnAfterGetRecord, SetLoadFields heuristics, temporary-table
  regressions, FlowField source-table widening, MaintainSQLIndex
  disabling SIFT.
- security (2 articles): environment-specific hardcoded GUIDs,
  ValidateTableRelation=false on user input.

Intentionally excluded: specific production P95 row-count numbers
(aggregated internal telemetry); rewritten as categorical guidance on
which tables to treat as production-scale without publishing sizes.

All articles use `bc-version: [all]` (applies to every BC version, per
the new schema sentinel). Validator passes with 0 errors / 0 warnings.
2026-04-23 16:43:42 +02:00

1.8 KiB

bc-version domain keywords technologies countries application-area
all
security
guid
tenant-id
aad
environment
hardcoded
al
w1
all

Hardcoded GUIDs are only safe for well-known system identifiers

Description

AL code sometimes carries hardcoded GUIDs. Some are platform-defined, stable across tenants and versions, and legitimately constant — the Base Application's ApplicationId ({437dbf0e-84ff-417a-965d-ed2bb9650972}) is the canonical example. Others identify a specific tenant, a specific Azure Active Directory application, or a specific environment; these look identical at the source-code level but are environment-bound and break the moment the extension is deployed anywhere else. Shipping an environment-specific GUID as a constant effectively locks the extension to one environment, and the failure mode in other tenants is usually an authentication error with no code-level signal pointing at the literal.

Best Practice

Hardcoded GUIDs are acceptable for well-known system identifiers that are stable across environments — document the identifier with a comment that names what it refers to. For tenant IDs, AAD application IDs, API subscription IDs, and any value that varies by deployment, retrieve at runtime from IsolatedStorage, configuration tables, or the platform APIs that expose the current tenant context.

See sample: do-not-hardcode-environment-specific-guids.good.al.

Anti Pattern

TenantId := '{12345678-1234-1234-1234-123456789012}'; or AadApplicationId := '{87654321-...}'; inline in a codeunit. The extension authenticates in one environment and fails in every other; debugging starts from an AAD error message that does not mention the literal.

See sample: do-not-hardcode-environment-specific-guids.bad.al.