feat(server fragments): server predefined fragments

added function addedServerFragments that concats relevent
fragments from the server to req query.
added function findFragments that return relevant fragments
for current request.
added function sliceFirstWord.
added serverFragments option.

resolves graphql#575

resources/build.js

@@ -16,7 +16,7 @@ const {
 } = require('./utils');
 
 if (require.main === module) {
-  rmdirRecursive('./dist');
+  // rmdirRecursive('./dist');
   mkdirRecursive('./dist');
 
   copyFile('./LICENSE', './dist/LICENSE');

resources/utils.js

@@ -38,12 +38,14 @@ function removeTrailingNewLine(str) {
 }
 
 function mkdirRecursive(dirPath) {
+  if(!fs.existsSync(dirPath))
   fs.mkdirSync(dirPath, { recursive: true });
 }
 
 function rmdirRecursive(dirPath) {
   if (fs.existsSync(dirPath)) {
     for (const dirent of fs.readdirSync(dirPath, { withFileTypes: true })) {
+      console.log("-------" + dirPath)
       const fullPath = path.join(dirPath, dirent.name);
       if (dirent.isDirectory()) {
         rmdirRecursive(fullPath);
@@ -59,9 +61,9 @@ function readdirRecursive(dirPath, opts = {}) {
   const { ignoreDir } = opts;
   const result = [];
   for (const dirent of fs.readdirSync(dirPath, { withFileTypes: true })) {
-    const name = dirent.name;
-    if (!dirent.isDirectory()) {
-      result.push(dirent.name);
+    const name = dirent;
+    if (!fs.statSync(path.resolve(dirPath, name)).isDirectory()) {
+      result.push(name);
       continue;
     }
 

src/index.js

@@ -238,6 +238,8 @@ function graphqlHTTP(options: Options): Middleware {
         const typeResolver = optionsData.typeResolver;
         const validationRules = optionsData.validationRules || [];
         const graphiql = optionsData.graphiql;
+        const serverFragments = optionsData.serverFragments;
+
         context = optionsData.context || request;
 
         // GraphQL HTTP only supports GET and POST methods.
@@ -247,7 +249,7 @@ function graphqlHTTP(options: Options): Middleware {
         }
 
         // Get GraphQL params from the request and POST body data.
-        query = params.query;
+        query = serverFragments ? addServerFragments(serverFragments, params.query) : params.query;
         variables = params.variables;
         operationName = params.operationName;
         showGraphiQL = canDisplayGraphiQL(request, params) && graphiql;
@@ -509,3 +511,87 @@ function sendResponse(response: $Response, type: string, data: string): void {
   response.setHeader('Content-Length', String(chunk.length));
   response.end(chunk);
 }
+
+/**
+ * Helper function to get the first word from string.
+ * 
+ * @param   { string } text - The full string.
+ * 
+ * @returns { string }      - First word.
+ */
+function sliceFirstWord(text: string): string {
+  let slicedText = text; 
+
+  const firstSpaceIndex = slicedText.indexOf(' ');
+
+  if(firstSpaceIndex !== -1) {
+    slicedText = slicedText.slice(0, firstSpaceIndex);
+  }
+
+  const firstEndRowIndex = slicedText.indexOf('\n');
+
+  if(firstEndRowIndex !== -1) {
+    slicedText = slicedText.slice(0, firstEndRowIndex);
+  }
+
+  return slicedText;
+}
+
+/**
+ * Helper recursive function that finds all the fragments from the server that are used in the current request.
+ * 
+ * @param   { string }      serverFragments - Fragments from the server.
+ * @param   { string }      query           - Query from the request.
+ * @param   { Set<string> } fragmentsInUsed - Set of relevant fragments.
+ * 
+ * @returns { Set<string> }                 - relevant fragments for current request.
+ */
+function findFragments(serverFragments: string, query: string, fragmentsInUsed: Set<string>): Set<string> {
+  // Fragment declaration starts with 'fragment' key word
+  // Slice to remove text before the first fragment declaration
+  let fragmentDeclarationFields = serverFragments.split('fragment ').slice(1);
+
+  // Fragment variable starts with spread - '...' 
+  // Slice to remove text before the first fragment variable
+  let fragmentVariableFields = query.split('...').slice(1);
+
+  fragmentVariableFields.forEach(fragmentVariable => {
+    const currFragmentVariableKeyName = sliceFirstWord(fragmentVariable);
+
+    for (let index = 0; index < fragmentDeclarationFields.length; index++) {
+      const currFragmentDeclaration = fragmentDeclarationFields[index];
+      const currFragmentDeclarationKeyName = sliceFirstWord(currFragmentDeclaration);
+
+      if(currFragmentDeclarationKeyName === currFragmentVariableKeyName) {
+
+        fragmentsInUsed.add(currFragmentDeclaration);
+
+        // Find fragments in the matching fragments
+        fragmentsInUsed = findFragments(serverFragments, currFragmentDeclaration, fragmentsInUsed)
+
+        break;
+      }
+
+    }
+  })
+
+  return fragmentsInUsed;
+}
+
+/**
+ * Add to query the relevant server fragments
+ * 
+ * @param {*} serverFragments - Fragments from the server.
+ * @param {*} query           - Query from the request.
+ * 
+ * @returns                   - Concat relevant fragments to request query
+ */
+function addServerFragments(serverFragments: string, query: string): string {
+  let fragmentsInUsed = '';
+
+  [...(findFragments(serverFragments, query, new Set()))].forEach(fullFragment => {
+    fragmentsInUsed += `fragment ${fullFragment} `;
+  })
+
+  return `${fragmentsInUsed}\n${query}`;
+}

types/index.d.ts

@@ -137,6 +137,10 @@ declare namespace graphqlHTTP {
      * `__typename` field or alternatively calls the `isTypeOf` method).
      */
     typeResolver?: GraphQLTypeResolver<unknown, unknown> | null;
+    /**
+     * ssssss
+     */
+    serverFragments: string,
   }
 
   /**