feat: add TypeBox/Ajv config schema package to the workspace (E00-S04-T01)

Adds packages/config (@personal-blog/config) — the EPPP configuration service foundation. The package defines the configuration schema with TypeBox (configSchema: host, port, databaseUrl, sessionSecret — the validated config fields, golden-tuple pins @sinclair/typebox@0.34.52 and ajv@8.20.0) and compiles it with Ajv (validateConfig). The environment adapter (T04), field-specific startup errors (T02) and secret redaction (T03) build on this boundary in later tasks; nothing reads process.env yet. Wiring for the new workspace package: lockfile importer + resolved typebox/ajv tree, apps/server/Dockerfile manifest copy (frozen in-image install must match the lockfile importers), config-schema CI job, package set fixtures (workspace-layout, workspace-config, strict-tsconfig, typescript-pin), probe-file gitignore entry.
2026-08-30 02:29:52 +00:00
parent 6a65d4c789
commit bcea489391
13 changed files with 229 additions and 5 deletions
@@ -0,0 +1,49 @@
+/**
+ * EPPP configuration validation — [E00-S04-T01] TypeBox/Ajv schema.
+ *
+ * Compiles the TypeBox `configSchema` with Ajv (the golden-tuple validator,
+ * Technology-Stack §5.2/§7) and exposes `validateConfig`, the generic
+ * schema-validation entry point: given an unknown value it reports whether
+ * the value is a valid configuration and the Ajv error messages otherwise.
+ *
+ * This is deliberately NOT the E00-S04-T02 field-specific startup error:
+ * `validateConfig` returns the raw schema-validation outcome (valid or not,
+ * with the Ajv messages) and performs no startup wiring — the adapter
+ * (E00-S04-T04) and the startup error formatting (E00-S04-T02) build on it
+ * in later tasks.
+ */
+
+import { Ajv } from 'ajv';
+
+import { configSchema } from './schema.js';
+
+/** Ajv instance for the config schema — `allErrors` reports every violation. */
+const ajv = new Ajv({ allErrors: true });
+
+/** The compiled validator — TypeBox schemas are JSON Schema, so Ajv compiles them directly. */
+const validateConfigValue = ajv.compile(configSchema);
+
+/** The outcome of validating a value against the config schema. */
+export interface ConfigValidationResult {
+  /** True when the value is a valid configuration. */
+  valid: boolean;
+  /** Ajv error messages, empty when `valid` is true. */
+  errors: string[];
+}
+
+/**
+ * Validates an unknown value against the config schema.
+ *
+ * @param value - the value to validate (typically the parsed config object)
+ * @returns `{ valid: true, errors: [] }` for a valid configuration, or
+ *   `{ valid: false, errors }` with the Ajv messages naming each violation
+ *   (e.g. `"must have required property 'sessionSecret'"`).
+ */
+export function validateConfig(value: unknown): ConfigValidationResult {
+  const valid = validateConfigValue(value);
+  if (valid) {
+    return { valid: true, errors: [] };
+  }
+  const errors = (validateConfigValue.errors ?? []).map((error) => error.message ?? 'invalid');
+  return { valid: false, errors };
+}