Implement endpoint to retrieve a sorted list of unique authors. Added…

… support for filtering by quoteCategory. (#131)

src/api/controllers/authorsController.js

@@ -0,0 +1,39 @@
+const quoteService = require("../services/quotesService");
+
+const authorsController = async (req, res, next) => {
+
+  try {
+
+    let quotesUrl = req.query.quotesUrl || '';
+
+    let quoteCategory = req.query.quoteCategory || '';
+
+    let quoteObject = {
+      quotesUrl,
+      quoteCategory,
+    }
+
+    const authors = await quoteService.getAuthors(quoteObject);
+
+    res.setHeader("Content-Type", "application/json");
+
+    res.header(
+      "Cache-Control",
+      "no-cache,max-age=0,no-store,s-maxage=0,proxy-revalidate"
+    );
+    res.header("Pragma", "no-cache");
+    res.header("Expires", "-1");
+    res.json(authors);
+
+  } catch (error) {
+    console.error(error);
+    res.send({
+      name: error.name,
+      message: error.message,
+    });
+  }
+};
+
+module.exports = {
+  authorsController
+};

src/api/routes/quotes-router.js

@@ -116,12 +116,16 @@
 
 
 const controllers = require('../controllers/quotesController');
+const authorsController = require('../controllers/authorsController');
 
 const defineRoutes = (app) => {
 
     // get a quote
     app.get('/quote', controllers.quoteController);
 
+    // get authors
+    app.get('/authors', authorsController.authorsController);
+
 }
 
 module.exports = defineRoutes;

src/api/services/quotesService.js

@@ -79,6 +79,46 @@ const getQuote = async (quoteObj) => {
   }
 };
 
+const getAuthors = async (quoteObj) => {
+  try {
+    let {quotesUrl, quoteCategory} = quoteObj;
+    let apiResponse;
+    let { customQuotesUrl, isValidUrl } = await getValidUrl(quotesUrl);
+    let isCustomQuote = false;
+
+    if (isValidUrl) {
+      //url from params is valid, proceed to verfiy the data
+      apiResponse = await requestApi(customQuotesUrl);
+
+      if (apiResponse.length > 0) {
+        if (apiResponse[0].author) {
+          isCustomQuote = true;
+        }
+      }
+    }
+    else if (quoteCategory) {
+      apiResponse = quoteFromCategory[quoteCategory];
+      isCustomQuote = true;
+    }
+
+    if(!isCustomQuote) {
+      apiResponse = await requestApi(url);
+    }
+
+    if (!apiResponse || apiResponse.length === 0) {
+      return [];
+    } 
+
+    // Get array of authors in alphabetical order and without duplicates
+    const authors = [...new Set(apiResponse.map(quote => quote.author).sort())];
+
+    return authors;
+  } catch (error) {
+    throw error;
+  }
+}
+
 module.exports = {
   getQuote,
+  getAuthors
 };