config-loader,backend-common: do not fail backend startup on config schema errors

Signed-off-by: Patrik Oldsberg <poldsberg@gmail.com>

.changeset/heavy-stingrays-talk.md

@@ -0,0 +1,5 @@
+---
+'@backstage/backend-common': patch
+---
+
+The backend will no longer fail to start up when configured secrets do not match the configuration schema.

.changeset/thirty-icons-buy.md

@@ -0,0 +1,5 @@
+---
+'@backstage/config-loader': minor
+---
+
+Added `ignoreSchemaErrors` to `schema.process`.

packages/backend-common/src/config.ts

@@ -41,7 +41,7 @@ const updateRedactionList = (
 ) => {
   const secretAppConfigs = schema.process(configs, {
     visibility: ['secret'],
-    withDeprecatedKeys: true,
+    ignoreSchemaErrors: true,
   });
   const secretConfig = ConfigReader.fromConfigs(secretAppConfigs);
   const values = new Set<string>();

packages/config-loader/api-report.md

@@ -19,6 +19,7 @@ export type ConfigSchema = {
 // @public
 export type ConfigSchemaProcessingOptions = {
   visibility?: ConfigVisibility[];
+  ignoreSchemaErrors?: boolean;
   valueTransform?: TransformFunc<any>;
   withFilteredKeys?: boolean;
   withDeprecatedKeys?: boolean;

packages/config-loader/src/lib/schema/load.test.ts

@@ -275,5 +275,12 @@ describe('loadConfigSchema', () => {
     ).toThrow(
       "Config must have required property 'x a' { missingProperty=x a } at /other",
     );
+
+    expect(
+      schema.process([{ data: { other: {} }, context: 'test' }], {
+        visibility: ['frontend'],
+        ignoreSchemaErrors: true,
+      }),
+    ).toEqual([{ data: {}, context: 'test' }]);
   });
 });

packages/config-loader/src/lib/schema/load.ts

@@ -82,18 +82,26 @@ export async function loadConfigSchema(
   return {
     process(
       configs: AppConfig[],
-      { visibility, valueTransform, withFilteredKeys, withDeprecatedKeys } = {},
+      {
+        visibility,
+        valueTransform,
+        withFilteredKeys,
+        withDeprecatedKeys,
+        ignoreSchemaErrors,
+      } = {},
     ): AppConfig[] {
       const result = validate(configs);
 
-      const visibleErrors = filterErrorsByVisibility(
-        result.errors,
-        visibility,
-        result.visibilityByDataPath,
-        result.visibilityBySchemaPath,
-      );
-      if (visibleErrors.length > 0) {
-        throw errorsToError(visibleErrors);
+      if (!ignoreSchemaErrors) {
+        const visibleErrors = filterErrorsByVisibility(
+          result.errors,
+          visibility,
+          result.visibilityByDataPath,
+          result.visibilityBySchemaPath,
+        );
+        if (visibleErrors.length > 0) {
+          throw errorsToError(visibleErrors);
+        }
       }
 
       let processedConfigs = configs;

packages/config-loader/src/lib/schema/types.ts

@@ -117,6 +117,11 @@ export type ConfigSchemaProcessingOptions = {
    */
   visibility?: ConfigVisibility[];
 
+  /**
+   * When set to `true`, any schema errors in the provided configuration will be ignored.
+   */
+  ignoreSchemaErrors?: boolean;
+
   /**
    * A transform function that can be used to transform primitive configuration values
    * during validation. The value returned from the transform function will be used