feat: add PokéAPI proxy (#465)

* feat: get basic proxy working

* fix: refactor project to something closer to domain driven design

* fix: set default CACHE_TTL_MINUTES in sample.env

* feat: add content and styling for landing proxy landing page

* feat: dockerize PokéAPI proxy

* fix: use hours to set ttl for caching, update sample env vars

* feat: add note to landing page about the format for pokémon with sex symbols as part of their name

* feat: add middleware and utility function cache and validate all pokémon names and ids served by PokéAPI

* feat: cache by id and name whenever fetching a valid pokémon from PokéAPI

* fix: simplify middleware and error handling, prettify code

* feat: add route to get all pokemon names and routes, refactor to improve caching

* feat: add ids to the list of all valid pokemon

* feat: add /pokemon route description and examples to the landing page

* feat: update README.md

* fix: add Dockerfile, set TTL env var

* fix: rename function to get all resources from /pokemon endpoint

README.md

@@ -180,6 +180,11 @@
 
 ### Main Curriculum
 
+- PokéAPI Proxy
+
+  - [Project description](https://www.freecodecamp.org/learn/2022/javascript-algorithms-and-data-structures/pokemon-search-app-project/build-a-pokemon-search-app)
+  - [Landing page](https://pokeapi-proxy.freecodecamp.rocks/)
+
 - Stock Price Checker Proxy
   - [Project description](https://www.freecodecamp.org/learn/information-security/information-security-projects/stock-price-checker)
   - [Landing page](https://stock-price-checker-proxy.freecodecamp.rocks/)

apps/pokeapi-proxy/.dockerignore

@@ -0,0 +1,6 @@
+.env
+.git
+.gitignore
+.dockerignore
+node_modules
+Dockerfile

apps/pokeapi-proxy/Dockerfile

@@ -0,0 +1,14 @@
+FROM node:18-bullseye-slim
+
+WORKDIR /app
+
+# Copy over all the files in the project directory to /app early
+# for rollup bundling
+COPY . . 
+
+ENV PORT=3000
+ENV CACHE_TTL_HOURS=${POKEAPI_PROXY_CACHE_TTL_HOURS}
+
+RUN npm ci
+
+CMD ["npm", "start"]

apps/pokeapi-proxy/README.md

@@ -0,0 +1 @@
+# PokéAPI Proxy

apps/pokeapi-proxy/api/pokemon/pokemon.handlers.mjs

@@ -0,0 +1,97 @@
+import axios from 'axios';
+import { getCache, setCache } from '../utils/cache.mjs';
+
+export const getPokemonEndpointResources = async (req, res, next) => {
+  try {
+    const { pokemonIdOrName } = req.params;
+    // Attempt to get all resources for the Pokémon endpoint from the cache
+    let pokemonEndpointResources = getCache('pokemonEndpointResources');
+
+    if (!pokemonEndpointResources) {
+      console.log(
+        'Fetching all resources for the Pokémon endpoint from PokéAPI'
+      );
+      const { data } = await axios.get(
+        `https://pokeapi.co/api/v2/pokemon/?limit=9000`
+      );
+      const { count, results } = data;
+
+      pokemonEndpointResources = {
+        count,
+        results: results.map(obj => {
+          const { name, url } = obj;
+          return {
+            id: Number(url.split('/').filter(Boolean).pop()),
+            name,
+            url: url.replace(
+              'https://pokeapi.co/api/v2/',
+              `${req.protocol}://${req.get('host')}/api/`
+            )
+          };
+        })
+      };
+
+      // Cache all Pokémon names and routes
+      setCache('pokemonEndpointResources', pokemonEndpointResources);
+    }
+
+    if (pokemonIdOrName) {
+      // User is requesting a specific Pokémon, so pass the data to the next middleware
+      // for id or name validation
+      res.locals.pokemonEndpointResources = pokemonEndpointResources;
+      next();
+    } else {
+      // User is requesting all Pokémon names and routes, so send the data as a response
+      res.send(pokemonEndpointResources);
+    }
+  } catch (err) {
+    next(err);
+  }
+};
+
+export const getPokemonData = async (req, res, next) => {
+  try {
+    const { pokemonIdOrName } = req.params;
+    console.log('Fetching Pokémon data from PokéAPI');
+    const { data } = await axios.get(
+      `https://pokeapi.co/api/v2/pokemon/${pokemonIdOrName}`
+    );
+    const {
+      base_experience,
+      height,
+      id,
+      name,
+      order,
+      sprites,
+      stats,
+      types,
+      weight
+    } = data;
+
+    // Remove unnecessary data for the required project
+    const simplifiedPokemonData = {
+      base_experience,
+      height,
+      id,
+      name,
+      order,
+      sprites: Object.keys(sprites)
+        .filter(key => typeof sprites[key] === 'string')
+        .reduce((obj, key) => {
+          obj[key] = sprites[key];
+          return obj;
+        }, {}),
+      stats,
+      types,
+      weight
+    };
+
+    // Cache simplified data by id and name, then send it as a response
+    setCache(simplifiedPokemonData.id, simplifiedPokemonData);
+    setCache(simplifiedPokemonData.name, simplifiedPokemonData);
+
+    res.send(simplifiedPokemonData);
+  } catch (err) {
+    next(err);
+  }
+};

apps/pokeapi-proxy/api/pokemon/pokemon.middleware.mjs

@@ -0,0 +1,45 @@
+import { getCache } from '../utils/cache.mjs';
+
+export const checkCache = (req, res, next) => {
+  const { pokemonIdOrName } = req.params;
+
+  try {
+    const cachedData = getCache(pokemonIdOrName || 'pokemonEndpointResources');
+
+    if (cachedData) {
+      console.log('Serving cached data');
+      return res.send(cachedData);
+    }
+
+    next();
+  } catch (err) {
+    next(err);
+  }
+};
+
+export const validateNameOrId = async (req, res, next) => {
+  try {
+    const { pokemonIdOrName } = req.params;
+    const validNamesAndIds = res.locals.pokemonEndpointResources.results.reduce(
+      (arr, currObj) => {
+        arr.push(currObj.name);
+        arr.push(currObj.url.split('/').filter(Boolean).pop());
+        return arr;
+      },
+      []
+    );
+
+    if (validNamesAndIds.includes(pokemonIdOrName)) {
+      next();
+    } else {
+      // Set custom error status code and message
+      const invalidPokemonErr = new Error();
+      invalidPokemonErr.statusCode = 404;
+      invalidPokemonErr.message = 'Invalid Pokémon name or id';
+
+      throw invalidPokemonErr;
+    }
+  } catch (err) {
+    next(err);
+  }
+};

apps/pokeapi-proxy/api/pokemon/pokemon.routes.mjs

@@ -0,0 +1,19 @@
+import {
+  getPokemonEndpointResources,
+  getPokemonData
+} from './pokemon.handlers.mjs';
+import { checkCache, validateNameOrId } from './pokemon.middleware.mjs';
+import express from 'express';
+const router = express.Router();
+
+router.get('/pokemon', checkCache, getPokemonEndpointResources);
+
+router.get(
+  '/pokemon/:pokemonIdOrName',
+  checkCache,
+  getPokemonEndpointResources,
+  validateNameOrId,
+  getPokemonData
+);
+
+export { router };

apps/pokeapi-proxy/api/utils/cache.mjs

@@ -0,0 +1,9 @@
+import NodeCache from 'node-cache';
+const cache = new NodeCache({
+  stdTTL: process.env.CACHE_TTL_HOURS * 3600, // Convert hours to seconds
+  checkperiod: 120
+});
+
+export const getCache = key => cache.get(key);
+
+export const setCache = (key, data) => cache.set(key, data);