[WIP] Introduce caching in loaders

.changeset/sour-ways-ring.md

@@ -0,0 +1,10 @@
+---
+'@graphql-tools/load': minor
+'@graphql-tools/code-file-loader': minor
+'@graphql-tools/graphql-file-loader': minor
+'@graphql-tools/json-file-loader': minor
+'@graphql-tools/module-loader': minor
+'@graphql-tools/utils': minor
+---
+
+Introduce caching in loaders

packages/load/src/load-typedefs/load-file.ts

@@ -1,6 +1,28 @@
-import { Source, debugLog } from '@graphql-tools/utils';
+import { Source, debugLog, Cacheable } from '@graphql-tools/utils';
 import { LoadTypedefsOptions } from '../load-typedefs';
 
+function makeCacheable<TPointer, TOptions extends Cacheable>(
+  fn: (pointer: TPointer, options?: TOptions) => Promise<Source | never>,
+  pointer: TPointer,
+  options: TOptions
+): Promise<Source | never> {
+  if (options?.cacheable) {
+    return options.cacheable(fn, pointer, options);
+  }
+  return fn(pointer, options);
+}
+
+function makeCacheableSync<TPointer, TOptions extends Cacheable>(
+  fn: (pointer: TPointer, options?: TOptions) => Source | never,
+  pointer: TPointer,
+  options: TOptions
+): Source | never {
+  if (options?.cacheableSync) {
+    return options.cacheableSync(fn, pointer, options);
+  }
+  return fn(pointer, options);
+}
+
 export async function loadFile(pointer: string, options: LoadTypedefsOptions): Promise<Source> {
   const cached = useCache({ pointer, options });
 
@@ -13,7 +35,7 @@ export async function loadFile(pointer: string, options: LoadTypedefsOptions): P
       const canLoad = await loader.canLoad(pointer, options);
 
       if (canLoad) {
-        const loadedValue = await loader.load(pointer, options);
+        const loadedValue = await makeCacheable(loader.load.bind(loader), pointer, options);
         return loadedValue;
       }
     } catch (error) {
@@ -37,7 +59,7 @@ export function loadFileSync(pointer: string, options: LoadTypedefsOptions): Sou
       const canLoad = loader.canLoadSync && loader.loadSync && loader.canLoadSync(pointer, options);
 
       if (canLoad) {
-        return loader.loadSync(pointer, options);
+        return makeCacheableSync(loader.loadSync.bind(loader), pointer, options);
       }
     } catch (error) {
       debugLog(`Failed to find any GraphQL type definitions in: ${pointer} - ${error.message}`);

packages/loaders/code-file/src/index.ts

@@ -50,6 +50,8 @@ const FILE_EXTENSIONS = ['.ts', '.tsx', '.js', '.jsx', '.vue'];
  * Supported extensions include: `.ts`, `.tsx`, `.js`, `.jsx`, `.vue`
  */
 export class CodeFileLoader implements UniversalLoader<CodeFileLoaderOptions> {
+  cacheable = true;
+
   loaderId(): string {
     return 'code-file';
   }
@@ -100,7 +102,7 @@ export class CodeFileLoader implements UniversalLoader<CodeFileLoaderOptions> {
         const sdl = await gqlPluckFromCodeString(normalizedFilePath, content, options.pluckConfig);
 
         if (sdl) {
-          return parseSDL({ pointer, sdl, options });
+          return parseSDL({ pointer: normalizedFilePath, sdl, options });
         }
       } catch (e) {
         debugLog(`Failed to load schema from code file "${normalizedFilePath}": ${e.message}`);
@@ -115,7 +117,7 @@ export class CodeFileLoader implements UniversalLoader<CodeFileLoaderOptions> {
         }
 
         const loaded = await tryToLoadFromExport(normalizedFilePath);
-        const source = resolveSource(pointer, loaded, options);
+        const source = resolveSource(normalizedFilePath, loaded, options);
 
         if (source) {
           return source;
@@ -143,7 +145,7 @@ export class CodeFileLoader implements UniversalLoader<CodeFileLoaderOptions> {
         const sdl = gqlPluckFromCodeStringSync(normalizedFilePath, content, options.pluckConfig);
 
         if (sdl) {
-          return parseSDL({ pointer, sdl, options });
+          return parseSDL({ pointer: normalizedFilePath, sdl, options });
         }
       } catch (e) {
         debugLog(`Failed to load schema from code file "${normalizedFilePath}": ${e.message}`);
@@ -158,7 +160,7 @@ export class CodeFileLoader implements UniversalLoader<CodeFileLoaderOptions> {
         }
 
         const loaded = tryToLoadFromExportSync(normalizedFilePath);
-        const source = resolveSource(pointer, loaded, options);
+        const source = resolveSource(normalizedFilePath, loaded, options);
 
         if (source) {
           return source;

packages/loaders/graphql-file/src/index.ts

@@ -55,6 +55,8 @@ function isGraphQLImportFile(rawSDL: string) {
  * ```
  */
 export class GraphQLFileLoader implements UniversalLoader<GraphQLFileLoaderOptions> {
+  cacheable = true;
+
   loaderId(): string {
     return 'graphql-file';
   }
@@ -94,16 +96,19 @@ export class GraphQLFileLoader implements UniversalLoader<GraphQLFileLoaderOptio
     return false;
   }
 
-  async load(pointer: SchemaPointerSingle | DocumentPointerSingle, options: GraphQLFileLoaderOptions): Promise<Source> {
+  loadSync(pointer: SchemaPointerSingle | DocumentPointerSingle, options: GraphQLFileLoaderOptions): Source {
     const normalizedFilePath = isAbsolute(pointer) ? pointer : resolve(options.cwd || processCwd(), pointer);
-    const rawSDL: string = await readFile(normalizedFilePath, { encoding: 'utf8' });
-
+    const rawSDL = readFileSync(normalizedFilePath, { encoding: 'utf8' });
     return this.handleFileContent(rawSDL, pointer, options);
   }
 
-  loadSync(pointer: SchemaPointerSingle | DocumentPointerSingle, options: GraphQLFileLoaderOptions): Source {
+  async load(
+    pointer: SchemaPointerSingle | DocumentPointerSingle,
+    options: GraphQLFileLoaderOptions
+  ): Promise<Source> {
     const normalizedFilePath = isAbsolute(pointer) ? pointer : resolve(options.cwd || processCwd(), pointer);
-    const rawSDL = readFileSync(normalizedFilePath, { encoding: 'utf8' });
+    const rawSDL: string = await readFile(normalizedFilePath, { encoding: 'utf8' });
+
     return this.handleFileContent(rawSDL, pointer, options);
   }
 

packages/loaders/json-file/src/index.ts

@@ -43,6 +43,8 @@ export interface JsonFileLoaderOptions extends SingleFileOptions {}
  * ```
  */
 export class JsonFileLoader implements DocumentLoader {
+  cacheable = true;
+
   loaderId(): string {
     return 'json-file';
   }

packages/loaders/module/src/index.ts

@@ -40,6 +40,8 @@ function extractData(
  * ```
  */
 export class ModuleLoader implements UniversalLoader {
+  cacheable = true;
+
   loaderId() {
     return 'module-loader';
   }

packages/utils/src/loaders.ts

@@ -9,9 +9,23 @@ export interface Source {
   location?: string;
 }
 
+export interface Cacheable {
+  cacheable?<TPointer, TOptions>(
+    fn: (pointer: TPointer, options?: TOptions) => PromiseLike<Source | never>,
+    pointer: TPointer,
+    options?: TOptions
+  ): Promise<Source | never>;
+  cacheableSync?<TPointer, TOptions>(
+    fn: (pointer: TPointer, options?: TOptions) => Source | never,
+    pointer: TPointer,
+    options?: TOptions
+  ): Source | never;
+}
+
 export type SingleFileOptions = GraphQLParseOptions &
   GraphQLSchemaValidationOptions &
-  BuildSchemaOptions & {
+  BuildSchemaOptions &
+  Cacheable & {
     cwd?: string;
   };
 
@@ -24,6 +38,7 @@ export type DocumentPointer = WithList<DocumentGlobPathPointer>;
 export type DocumentPointerSingle = ElementOf<DocumentPointer>;
 
 export interface Loader<TPointer = string, TOptions extends SingleFileOptions = SingleFileOptions> {
+  cacheable?: boolean;
   loaderId(): string;
   canLoad(pointer: TPointer, options?: TOptions): Promise<boolean>;
   canLoadSync?(pointer: TPointer, options?: TOptions): boolean;