Documentation
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Overview ¶
Package celsql compiles a CEL expression (a "cel"-flavored calculated search source, SD-9/FR-A6) into equivalent SQL text expressions — one for Postgres (fed to to_tsvector, SD-7) and one for the SQLite fallback (FR-B5) — after type-checking the CEL against the resource's proto message descriptor.
Why this package lives under cmd/ (WS-011 / FR-X1 graph isolation) ¶
github.com/google/cel-go is a build-time-only concern: search sources are compiled to SQL during codegen and never at runtime. cel-go MUST NOT enter the devedge-sdk *root* module's runtime dependency graph (a downstream app that imports only .../server must stay light; see scripts/check-graph-isolation.sh).
The root package internal/aip is imported at runtime by middleware/redact, so the CEL compiler cannot live there. It lives here in the cmd module (github.com/infobloxopen/devedge-sdk/cmd), a separate nested module that already carries the codegen-only heavy dependencies (the CLI imports ent/gorm). The root module does not require cmd — cmd requires root — so cel-go reaches only the cmd build closure. This package is internal to cmd and is meant to be consumed ONLY by the cmd/protoc-gen-* plugins (wiring is a later task; this file is the standalone compiler).
Supported subset (and nothing more) ¶
The compiler accepts exactly the constructs the DDI search shapes need and fails loud, naming the offending construct, on anything else — it never guesses SQL:
- field references: msg.<field> → the quoted column
- ternary cond ? a : b → CASE WHEN <cond> THEN a ELSE b END
- map-literal lookup {k:v, ...}[key] → CASE <key> WHEN k THEN v ... END
- string concat a + b → a || b
- string ops .lowerAscii(), .replace(f, t) → lower(...), replace(...)
- message / map / tags access msg.m.f, m[k] → Postgres ->>/#>> , SQLite json_extract
- equality / boolean conditions (only inside a ternary/map condition): ==, !=, &&, ||, ! → =, <>, AND, OR, NOT
Arithmetic, comparisons other than ==/!=, comprehensions (.map/.filter/.exists), list/struct literals, and any function outside {replace, lowerAscii} are rejected.
Index ¶
Constants ¶
const RootVar = "msg"
RootVar is the CEL variable bound to the resource message. Field references in a search source are written against it, e.g. `msg.display_name`.
Variables ¶
This section is empty.
Functions ¶
func CompileCEL ¶
func CompileCEL(expr string, md protoreflect.MessageDescriptor) (postgresExpr, sqliteExpr string, err error)
CompileCEL type-checks expr against md, then compiles the supported subset into an equivalent Postgres text expression (suitable as a to_tsvector argument) and an equivalent SQLite-fallback text expression. It returns a descriptive error — naming the unsupported construct — for any CEL outside the supported subset, rather than emitting wrong or guessed SQL.
Types ¶
This section is empty.
Source Files