Newsreader Backend

The purpose of this project is to show how to minipulate data and queries through GraphQL in order to define a structure of data returned by endpoints API.

First of all GraphQL defines the schemas, the structure of your dataset using TypeDefs. Then let Apollo Server know how to interact with this schema thanks to the resolver, it explicitly indicates how to retrieve a particular type of data.
Finally, Apollo uses a Data sources extended class that sets methods to making requests to external APIs and retrieves data.

The tests has been done with Jest to validate data sources and a custom black-box tests for typedefs and resolvers.

GraphQL

Schemas

export const typeDefs = gql`
  type Query {
    allArticles: [Article!]!
    allArticlesBySource(source: String!): [Article!]!
    articleBySource(id: ID!, source: String!): Article
    multipleArticlesBySource(ids: [Int!]!, source: String!): [Article!]!
  }

  type Article {
    id: ID!
    title: String
    author: String
    url: String
    time: String
    source: String
  }
`

Resolvers

export const resolvers = {
  Query: {
    allArticles: (_, __, { dataSources }) =>
      Promise.all(
        Object.keys(dataSources).map((source) =>
          dataSources[source].getAllArticles()
        )
      ).then((result) => result.reduce((acc, data) => acc.concat(data)), []),
    allArticlesBySource: (_, { source }, { dataSources }) =>
      dataSources[source].getAllArticles(),
    articleBySource: (_, { id, source }, { dataSources }) =>
      dataSources[source].getArticle(id, source),
    multipleArticlesBySource: (_, { ids, source }, { dataSources }) =>
      dataSources[source].getArticlesByIds(ids),
  },
}

Data sources API

all classes are extended from Apollo RESTDataSource

class HackerNewsAPI

base url: https://hacker-news.firebaseio.com/v0/

method	param	description
articleReducer	{id, by, url, time, title}: Object	return a friendly formated data
getAllArticleIds	none	retrieve all articles ID
getArticle	articleId: Number	get an article by ID
getArticlesByIds	articleIds: Array of Number	get several articles by ID
getAllArticles	none	get all articles

class NewYorkTimesAPI

base url: https://api.nytimes.com/svc/mostpopular/v2/viewed/1.json?api-key=YOUR-KEY-API

method	param	description
articleReducer	{id, by, url, time, title}: Object	return a friendly formated data
getAllArticles	none	get all articles