Update the instructions and the answer of the Ballerina billionare exercise

exercises/practice/http-billion-dollar-question/.docs/instructions.md

@@ -4,19 +4,21 @@
 
 You have been asked to find the top `x` billionaires by net worth in a given set of countries (number of countries = `N`). To implement that, you have been given access to an API that returns the details of the billionaires by country.
 
-To simplify accessing the API, you can use the [`ims/billionairehub` client](https://lib.ballerina.io/ims/billionairehub/1.0.0/clients/Client) connector to connect to the API which returns details of the billionaires by country.
+To simplify accessing the API, you can use a predefined client connector to connect to the API which returns details of the billionaires by country.
 
 
 ```ballerina
-import ims/billionairehub;
+import ballerina_exercism/http_billion_dollar_question.billionairehub_server as _;
+import ballerina_exercism/http_billion_dollar_question.billionairehub_client as billionairehubClient;
 
-# Client ID and Client Secret to connect to the billionaire API
-configurable string clientId = ?;
-configurable string clientSecret = ?;
+type Billionaire record {|
+    string name;
+    float netWorth;
+
+|};
 
 public function getTopXBillionaires(string[] countries, int x) returns string[]|error {
-    // Create the client connector
-    billionairehub:Client cl = check new ({auth: {clientId, clientSecret}});
+    billionairehubClient:billionaireClient cl = check new();
 
     // TODO Write your logic here
     return [];
@@ -55,16 +57,15 @@ Limit: 5
 Output
 
 ```
-["Mukesh Ambani", "Gautam Adani & family", "Zhong Shanshan", "Zhang Yiming", "Ma Huateng"]
+["Mukesh Ambani","Zhong Shanshan","Ma Huateng","Colin Huang","Pony Ma"]
 ```
 
 ## Test Environment
 
-* Client ID and Client Secret to connect to the billionaire API have been provided to you in the `tests/Config.toml`. You can use them to initialize the client.
 * Use `bal test` to run and test your implementation.
 
 ## Hints
 
-* `ims/billionairehub` package's [client](https://lib.ballerina.io/ims/billionairehub/1.0.0/clients/Client) can be used to invoke the get billionaires by country API. You can use the `getBillionaires("<country>")` remote method specifically.
+* `http_billion_dollar_question` package's `billionairehub_client` module can be used to invoke the get billionaires by country API. You can use the `getBillionaires("<country>")` remote method specifically.
 * You can find the richest people per country first and then combine them to find the top `x`
 * [Query expressions](https://ballerina.io/learn/by-example/query-expressions/) will be convenient for filtering and sorting

exercises/practice/http-billion-dollar-question/.meta/config.json

@@ -19,5 +19,5 @@
   "icon": "elons-toys",
   "blurb": "Can you find the top billionaires by net worth in a given set of countries?",
   "source": "This is an exercise to introduce users to using Ballerina HTTP service data binding",
-  "source_url": "https://ballerina.io/learn/by-example/http-data-binding"
+  "source_url": "https://ballerina.io/learn/by-example/http-service-data-binding/"
 }

exercises/practice/http-billion-dollar-question/.meta/reference/main.bal

@@ -1,24 +1,13 @@
-import ballerina/io;
-import ims/billionairehub;
+import ballerina_exercism/http_billion_dollar_question.billionairehub_server as _;
+import ballerina_exercism/http_billion_dollar_question.billionairehub_client as billionairehubClient;
 
-configurable string clientId = ?;
-configurable string clientSecret = ?;
-
-public function main() returns error? {
-    billionairehub:Client cl = check new ({auth: {clientId, clientSecret}});
-    billionairehub:Billionaire[] billionaires = check cl->getBillionaires("France");
-    io:println(billionaires);
-
-    map<boolean> industries = {};
-    check from var b in billionaires
-        do {
-            industries[b.industry] = true;
-        };
-    io:println(industries.keys());
-}
+type Billionaire record {|
+    string name;
+    float netWorth;
+|};
 
 public function getTopXBillionaires(string[] countries, int x) returns string[]|error {
-    billionairehub:Billionaire[] billionaires = [];
+    Billionaire[] billionaires = [];
     foreach string country in countries {
         billionaires.push(...check getTopXBillionairesByCountry(country, x));
     }
@@ -29,9 +18,9 @@ public function getTopXBillionaires(string[] countries, int x) returns string[]|
         select b.name;
 }
 
-function getTopXBillionairesByCountry(string country, int x) returns billionairehub:Billionaire[]|error {
-    billionairehub:Client cl = check new ({auth: {clientId, clientSecret}});
-    billionairehub:Billionaire[] billionaires = check cl->getBillionaires(country);
+function getTopXBillionairesByCountry(string country, int x) returns Billionaire[]|error {
+    billionairehubClient:BillionaireClient cl = check new();
+    Billionaire[] billionaires = check cl->getBillionaires(country);
     return from var b in billionaires
         order by b.netWorth descending
         limit x

exercises/practice/http-billion-dollar-question/main.bal

@@ -1,12 +1,18 @@
-import ims/billionairehub;
+import ballerina_exercism/http_billion_dollar_question.billionairehub_server as _;
+import ballerina_exercism/http_billion_dollar_question.billionairehub_client as billionairehubClient;
 
-# Client ID and Client Secret to connect to the billionaire API
-configurable string clientId = ?;
-configurable string clientSecret = ?;
+type Billionaire record {|
+    string name;
+    float netWorth;
+|};
 
+# Returns the top billionaires of the given countries.
+#
+# + countries - countries to search for billionaires
+# + x - number of billionaires to return
+# + return - list of billionaires
 public function getTopXBillionaires(string[] countries, int x) returns string[]|error {
-    // Create the client connector
-    billionairehub:Client cl = check new ({auth: {clientId, clientSecret}});
+    billionairehubClient:BillionaireClient cl = check new();
 
     // TODO Write your logic here
     return [];

exercises/practice/http-billion-dollar-question/modules/billionairehub_client/client.bal

@@ -0,0 +1,20 @@
+import ballerina/http;
+
+type Billionaire record {|
+    string name;
+    float netWorth;
+|};
+
+const string clientUrl = "http://localhost:9090";
+
+public client class BillionaireClient {
+    private final http:Client httpClient;
+
+    public function init() returns error? {
+        self.httpClient = check new (clientUrl);
+    }
+
+    remote function getBillionaires(string country) returns Billionaire[]|error {
+        return self.httpClient->/getBillionaires(country=country);
+    }
+}

exercises/practice/http-billion-dollar-question/modules/billionairehub_server/resources/billionaires.json

@@ -0,0 +1 @@
+{"United States":[{"name":"Elon Musk", "netWorth":177}, {"name":"Jeff Bezos", "netWorth":151}, {"name":"Bill Gates", "netWorth":124}, {"name":"Mark Zuckerberg", "netWorth":97}, {"name":"Larry Ellison", "netWorth":93}, {"name":"Larry Page", "netWorth":91.5}, {"name":"Sergey Brin", "netWorth":89}, {"name":"Warren Buffett", "netWorth":88}, {"name":"Steve Ballmer", "netWorth":68}, {"name":"Mukesh Ambani", "netWorth":84}], "China":[{"name":"Zhong Shanshan", "netWorth":68}, {"name":"Zhang Yiming", "netWorth":35}, {"name":"Ma Huateng", "netWorth":65}, {"name":"Jack Ma", "netWorth":48}, {"name":"Colin Huang", "netWorth":55}, {"name":"Pony Ma", "netWorth":55}, {"name":"He Xiangjian", "netWorth":43}, {"name":"Yang Huiyan & family", "netWorth":29}, {"name":"Wang Xing", "netWorth":27}, {"name":"William Lei Ding", "netWorth":27}], "India":[{"name":"Mukesh Ambani", "netWorth":84}, {"name":"Gautam Adani & family", "netWorth":50}, {"name":"Shiv Nadar", "netWorth":23}, {"name":"Radhakishan Damani", "netWorth":16}, {"name":"Lakshmi Mittal", "netWorth":18}, {"name":"Hinduja brothers", "netWorth":17}, {"name":"Cyrus Poonawalla", "netWorth":12}, {"name":"Uday Kotak", "netWorth":15}, {"name":"Sunil Mittal & family", "netWorth":11}, {"name":"Kumar Birla", "netWorth":10}], "Japan":[{"name":"Tadashi Yanai & family", "netWorth":31}, {"name":"Takemitsu Takizaki", "netWorth":28}, {"name":"Masayoshi Son", "netWorth":29}, {"name":"Nobutada Saji & family", "netWorth":28}, {"name":"Takemitsu Takizaki", "netWorth":28}, {"name":"Hiroshi Mikitani", "netWorth":24}, {"name":"Yasumitsu Shigeta", "netWorth":24}, {"name":"Takemitsu Takizaki", "netWorth":28}, {"name":"Takemitsu Takizaki", "netWorth":28}, {"name":"Takemitsu Takizaki", "netWorth":28}], "Hong Kong":[{"name":"Li Ka-shing", "netWorth":35}, {"name":"Lee Shau Kee", "netWorth":28}, {"name":"Raymond Kwok & family", "netWorth":17}, {"name":"Thomas Kwok & family", "netWorth":17}, {"name":"Peter Woo", "netWorth":14}, {"name":"Joseph Lau", "netWorth":17}, {"name":"Cheng Yu-tung & family", "netWorth":17}, {"name":"Lui Che Woo & family", "netWorth":15}, {"name":"Henry Cheng & family", "netWorth":15}, {"name":"Michael Kadoorie & family", "netWorth":13}], "Russia":[{"name":"Vladimir Lisin", "netWorth":24}, {"name":"Vladimir Potanin", "netWorth":23}, {"name":"Alexey Mordashov & family", "netWorth":22}, {"name":"Leonid Mikhelson", "netWorth":20}, {"name":"Gennady Timchenko", "netWorth":20}, {"name":"Vagit Alekperov", "netWorth":19}, {"name":"Alisher Usmanov", "netWorth":19}, {"name":"Viktor Vekselberg", "netWorth":17}, {"name":"Roman Abramovich", "netWorth":17}, {"name":"Andrey Melnichenko", "netWorth":16}], "Italy":[{"name":"Leonardo Del Vecchio & family", "netWorth":25}, {"name":"Stefano Pessina", "netWorth":12}, {"name":"Massimiliana Landini Aleotti & family", "netWorth":13}, {"name":"Giovanni Ferrero", "netWorth":35}, {"name":"Giorgio Armani", "netWorth":8}, {"name":"Sergio Marchionne", "netWorth":5}, {"name":"Stefano Pessina", "netWorth":12}, {"name":"Massimiliana Landini Aleotti & family", "netWorth":13}, {"name":"Giovanni Ferrero", "netWorth":35}, {"name":"Giorgio Armani", "netWorth":8}], "France":[{"name":"Bernard Arnault & family", "netWorth":150}, {"name":"Francoise Bettencourt Meyers & family", "netWorth":71}, {"name":"Francois Pinault & family", "netWorth":42}, {"name":"Alain Wertheimer", "netWorth":33}, {"name":"Gerard Wertheimer", "netWorth":33}, {"name":"Serge Dassault & family", "netWorth":26}, {"name":"Patrick Drahi", "netWorth":21}, {"name":"Xavier Niel", "netWorth":13}, {"name":"Alain Merieux & family", "netWorth":7}, {"name":"Vincent Bollore", "netWorth":7}], "Germany":[{"name":"Beate Heister & Karl Albrecht Jr.", "netWorth":39}, {"name":"Dieter Schwarz", "netWorth":35}, {"name":"Susanne Klatten", "netWorth":29}, {"name":"Stefan Quandt", "netWorth":29}, {"name":"Heinz Hermann Thiele & family", "netWorth":22}, {"name":"Klaus-Michael Kuhne", "netWorth":20}, {"name":"August von Finck", "netWorth":20}, {"name":"Michael Otto & family", "netWorth":19}, {"name":"Hasso Plattner & family", "netWorth":15}, {"name":"Reinhold Wurth & family", "netWorth":12}], "Australia":[{"name":"Gina Rinehart", "netWorth":31}, {"name":"Andrew Forrest", "netWorth":23}, {"name":"Anthony Pratt & family", "netWorth":19}, {"name":"James Packer", "netWorth":3}, {"name":"Harry Triguboff", "netWorth":12}, {"name":"Frank Lowy", "netWorth":6}, {"name":"John Gandel", "netWorth":6}, {"name":"Stan Perron", "netWorth":2}, {"name":"Kerr Neilson", "netWorth":2}, {"name":"Lindsay Fox", "netWorth":2}], "Indonesia":[{"name":"Robert Budi Hartono", "netWorth":20}, {"name":"Michael Hartono", "netWorth":20}, {"name":"Sri Prakash Lohia", "netWorth":13}, {"name":"Eka Tjipta Widjaja & family", "netWorth":9}, {"name":"Anthoni Salim & family", "netWorth":7}, {"name":"Tahir", "netWorth":4}, {"name":"Sukanto Tanoto", "netWorth":4}, {"name":"Peter Sondakh", "netWorth":3}, {"name":"Low Tuck Kwong", "netWorth":3}, {"name":"Putera Sampoerna", "netWorth":3}], "Canada":[{"name":"David Thomson & family", "netWorth":39}, {"name":"Joseph Tsai", "netWorth":10}, {"name":"Galen Weston & family", "netWorth":10}, {"name":"James Irving", "netWorth":8}, {"name":"Jim Pattison", "netWorth":7}, {"name":"Emanuele (Lino) Saputo", "netWorth":5}, {"name":"Alain Bouchard", "netWorth":4}, {"name":"Charles Bronfman", "netWorth":2}, {"name":"Michael Lee-Chin", "netWorth":2}, {"name":"Daryl Katz", "netWorth":2}], "Finland":[{"name":"Antti Herlin & family", "netWorth":13}, {"name":"Heikki Kyostila", "netWorth":5}, {"name":"Ilkka Herlin", "netWorth":4}, {"name":"Mika Anttonen", "netWorth":3}, {"name":"Niklas Herlin", "netWorth":3}, {"name":"Ilona Herlin", "netWorth":3}, {"name":"Ilkka Paananen", "netWorth":2}, {"name":"Hannu Haukka", "netWorth":2}, {"name":"Matti Marjanen", "netWorth":2}, {"name":"Mika Ihamuotila", "netWorth":2}], "Mexico":[{"name":"Carlos Slim Helu & family", "netWorth":52}, {"name":"German Larrea Mota Velasco & family", "netWorth":27}, {"name":"Alberto Bailleres Gonzalez & family", "netWorth":10}, {"name":"Ricardo Salinas Pliego & family", "netWorth":9}, {"name":"Maria Asuncion Aramburuzabala & family", "netWorth":5}, {"name":"Juan Francisco Beckmann Vidal & family", "netWorth":5}, {"name":"Roberto Hernandez Ramirez & family", "netWorth":4}, {"name":"Carlos Hank Rhon", "netWorth":2}, {"name":"Antonio del Valle Ruiz & family", "netWorth":2}, {"name":"Carlos Peralta Quintero", "netWorth":2}]}

exercises/practice/http-billion-dollar-question/modules/billionairehub_server/server.bal

@@ -0,0 +1,23 @@
+import ballerina/http;
+import ballerina/io;
+
+type Billionaire record {|
+    string name;
+    float netWorth;
+|};
+
+service / on new http:Listener(9090) {
+    map<Billionaire[]> topbillionaires = {};
+
+    resource function get getBillionaires(string country) returns Billionaire[]|error {
+        if self.topbillionaires.length() == 0 {
+            json billionaireDetails = check io:fileReadJson("modules/billionairehub_server/resources/billionaires.json");
+            self.topbillionaires = check billionaireDetails.cloneWithType();
+        }
+        Billionaire[]? billionaires = self.topbillionaires[country];
+        if billionaires is Billionaire[] {
+            return billionaires;
+        }
+        return error(country + " is not found in the sample dataset.");
+    }
+}

exercises/practice/http-billion-dollar-question/tests/tests.bal

@@ -24,22 +24,22 @@ function validData() returns map<[string[], int, string[]]> {
         "case2": [
             ["China", "India"],
             5,
-            ["Mukesh Ambani", "Gautam Adani & family", "Zhong Shanshan", "Zhang Yiming", "Ma Huateng"]
+            ["Mukesh Ambani","Zhong Shanshan","Ma Huateng","Colin Huang","Pony Ma"]
         ],
         "case3": [
             ["China", "India", "Japan", "Hong Kong"],
             10,
-            ["Mukesh Ambani", "Gautam Adani & family", "Zhong Shanshan", "Zhang Yiming", "Robin Zeng", "Ma Huateng", "Li Ka-shing", "Lee Shau Kee", "Shiv Nadar", "He Xiangjian"]
+            ["Mukesh Ambani","Zhong Shanshan","Ma Huateng","Colin Huang","Pony Ma","Gautam Adani & family","Jack Ma","He Xiangjian","Zhang Yiming","Li Ka-shing"]
         ],
         "case4": [
             ["Russia", "Italy", "France", "Germany", "Australia"],
             3,
-            ["Bernard Arnault & family", "Francoise Bettencourt Meyers & family", "Dieter Schwarz"]
+            ["Bernard Arnault & family","Francoise Bettencourt Meyers & family","Francois Pinault & family"]
         ],
         "case5": [
             ["Indonesia", "Japan", "Hong Kong"],
             7,
-            ["Robin Zeng", "Li Ka-shing", "Lee Shau Kee", "Tadashi Yanai & family", "Takemitsu Takizaki", "R. Budi Hartono", "Michael Hartono"]
+            ["Li Ka-shing","Tadashi Yanai & family","Masayoshi Son","Takemitsu Takizaki","Nobutada Saji & family","Takemitsu Takizaki","Takemitsu Takizaki"]
         ],
         "case6": [
             ["India"],
@@ -49,7 +49,7 @@ function validData() returns map<[string[], int, string[]]> {
         "case7": [
             ["Russia"],
             3,
-            ["Vladimir Lisin", "Vladimir Potanin"]
+            ["Vladimir Lisin","Vladimir Potanin","Alexey Mordashov & family"]
         ],
         "case8": [
             ["Mexico"],
@@ -59,7 +59,7 @@ function validData() returns map<[string[], int, string[]]> {
         "case9": [
             ["Canada", "Finland"],
             2,
-            ["Changpeng Zhao", "David Thomson & family"]
+            ["David Thomson & family","Antti Herlin & family"]
         ]
     };
 }