feat(#133): improves error message for $env missing values

Author: joelgallant

app-config-extension-utils/src/index.ts

@@ -37,6 +37,17 @@ export function forKey(
   };
 }
 
+export function keysToPath(keys: ParsingExtensionKey[]): string {
+  if (keys.length === 0) return 'root';
+
+  return (
+    keys
+      .map(([, k]) => k)
+      .filter((v) => v)
+      .join('.') || 'root'
+  );
+}
+
 export class ParsingExtensionInvalidOptions extends AppConfigError {}
 
 export function validateOptions<T>(
@@ -90,13 +101,9 @@ export function validationFunction<T>(
     } catch (error) {
       const message = error instanceof Error ? error.message : 'unknown';
 
-      const parents =
-        ctx
-          .map(([, k]) => k)
-          .filter((v) => !!v)
-          .join('.') || 'root';
-
-      throw new ParsingExtensionInvalidOptions(`Validation failed in "${parents}": ${message}`);
+      throw new ParsingExtensionInvalidOptions(
+        `Validation failed in "${keysToPath(ctx)}": ${message}`,
+      );
     }
   };
 }

app-config-extensions/src/index.ts

@@ -1,6 +1,7 @@
 import isEqual from 'lodash.isequal';
 import {
   forKey,
+  keysToPath,
   validateOptions,
   validationFunction,
   ValidationFunction,
@@ -173,7 +174,7 @@ export function envDirective(
     '$env',
     validateOptions(
       (SchemaBuilder) => SchemaBuilder.emptySchema().addAdditionalProperties(),
-      (value) => (parse) => {
+      (value, _, ctx) => (parse) => {
         if (!environment) {
           if ('none' in value) {
             return parse(value.none, metadata);
@@ -184,7 +185,9 @@ export function envDirective(
           }
 
           throw new AppConfigError(
-            `An $env directive was used, but current environment (eg. NODE_ENV) is undefined`,
+            `An $env directive was used (in ${keysToPath(
+              ctx,
+            )}), but current environment (eg. NODE_ENV) is undefined`,
           );
         }
 
@@ -201,7 +204,9 @@ export function envDirective(
         const found = Object.keys(value).join(', ');
 
         throw new AppConfigError(
-          `An $env directive was used, but none matched the current environment (wanted ${environment}, saw [${found}])`,
+          `An $env directive was used (in ${keysToPath(
+            ctx,
+          )}), but none matched the current environment (wanted ${environment}, saw [${found}])`,
         );
       },
       // $env is lazy so that non-applicable envs don't get evaluated