Better error messages etc

Author: jdolle

packages/libraries/linkable-specs/README.md

@@ -37,27 +37,26 @@ type User {
 // specs.ts
 
 const exampleSpec = new LinkableSpec('https://specs.graphql-hive.com/example', {
-  'v0.1': (resolveImportName) => (typeDefs: DocumentNode) => {
-    const examples: Record<string, string> = {};
-    const exampleName = resolveImportName('@example');
+  'v0.1': resolveImportName => (typeDefs: DocumentNode) => {
+    const examples: Record<string, string> = {}
+    const exampleName = resolveImportName('@example')
     visit(typeDefs, {
       FieldDefinition: node => {
-        const example = node.directives?.find(d => d.name.value === exampleName);
+        const example = node.directives?.find(d => d.name.value === exampleName)
         if (example) {
-          examples[node.name.value] =
-            (
-              example.arguments?.find(a => a.name.value === 'eg')?.value as
-                | StringValueNode
-                | undefined
-            )?.value;
+          examples[node.name.value] = (
+            example.arguments?.find(a => a.name.value === 'eg')?.value as
+              | StringValueNode
+              | undefined
+          )?.value
         }
-      },
-    });
-    return examples;
-  },
-});
-const typeDefs = parse(sdl);
-const linkedSpecs = detectLinkedImplementations(typeDefs, [exampleSpec]);
+      }
+    })
+    return examples
+  }
+})
+const typeDefs = parse(sdl)
+const linkedSpecs = detectLinkedImplementations(typeDefs, [exampleSpec])
 const result = linkedSpecs.map(apply => apply(typeDefs))
 
 // result[0] ==> { user: "query { user { id name } }"}

packages/libraries/linkable-specs/src/link-url.ts

@@ -39,15 +39,15 @@ export class FederatedLinkUrl {
     if (versionOrName) {
       if (VERSION_MATCH.test(versionOrName)) {
         const maybeName = parts[parts.length - 2];
-        return new this(
+        return new FederatedLinkUrl(
           url.origin + (maybeName ? `/${parts.slice(0, parts.length - 1).join('/')}` : ''),
           maybeName ?? null,
           versionOrName,
         );
       }
-      return new this(`${url.origin}/${parts.join('/')}`, versionOrName, null);
+      return new FederatedLinkUrl(`${url.origin}/${parts.join('/')}`, versionOrName, null);
     }
-    return new this(url.origin, null, null);
+    return new FederatedLinkUrl(url.origin, null, null);
   };
 
   /** Check if this version supports another version */
@@ -69,7 +69,7 @@ export class FederatedLinkUrl {
       major = majorOrVersion.major;
       minor = majorOrVersion.minor;
     } else {
-      throw new Error('Unsupported argument.');
+      throw new Error(`Unsupported version argument: ${args}.`);
     }
     return this.isCompatibleVersion(major, minor);
   }

packages/libraries/linkable-specs/src/link.ts

@@ -1,4 +1,4 @@
-import { ConstArgumentNode, DocumentNode, Kind, StringValueNode } from 'graphql';
+import { ConstArgumentNode, DocumentNode, Kind } from 'graphql';
 import { FederatedLinkImport } from './link-import';
 import { FederatedLinkUrl } from './link-url';
 
@@ -9,19 +9,27 @@ function linkFromArgs(args: readonly ConstArgumentNode[]): FederatedLink | undef
   for (const arg of args) {
     switch (arg.name.value) {
       case 'url': {
-        url = FederatedLinkUrl.fromUrl((arg.value as StringValueNode).value);
+        if (arg.value.kind === Kind.STRING) {
+          url = FederatedLinkUrl.fromUrl(arg.value.value);
+        } else {
+          console.warn(`Unexpected kind, ${arg.value.kind}, for argument "url" in @link.`);
+        }
         break;
       }
       case 'import': {
         imports = FederatedLinkImport.fromTypedefs(arg.value);
         break;
       }
       case 'as': {
-        as = (arg?.value as StringValueNode | undefined)?.value ?? null;
+        if (arg.value.kind === Kind.STRING) {
+          as = arg.value.value ?? null;
+        } else {
+          console.warn(`Unexpected kind, ${arg.value.kind}, for argument "as" in @link.`);
+        }
         break;
       }
       default: {
-        // console.warn('Unknown argument');
+        // ignore. Federation should validate links.
       }
     }
   }