Linux - tested on Ubuntu 18 (might work on mac)
Go version 1.12 (might run on 1.11 - requires go mod)
Docker (I am running v. 19.03.2)
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Install and start the DB. It is a mysql docker container.
chmod +x start.db./start.db
... Wait until its up
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Compile and run the app.
go build main.go- compile./main- run the app! (will run the migrations on start up)
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Seed the DB with news sources.
chmod +x seed-db.sh./seed-db.sh
Run the tests go test ./...
Designed in a micro-services (within monolith) pattern, As we scale, we can break the app up and scale it horizontally. The services and repos are programmed to interface and implemented as singletons. Down the line we can generate clients for our extracted services and easily break the app up.
I focused on delivering value. I have taken a pragmatic approach to testing in order to deliver the API. We could do with some integration tests and probably more unit tests. Any logic that is not simple object mapping I have unit tested.
I would like to have added a cache layer but ran out-of-time. I would have implemented the cache on the GET news/:id route.
There is also no security on the app.
inline comments in italics
Our client wants to be able to read news articles from a provided feed that can be shown in a mobile app. They already have another team working on the app itself, but need help with the backend API.
For context, the mobile to achieveapp has the following functionality:
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Load news articles from a public news feed
☑ Endpoint added to load news articles from both RSS feeds, separate parsers to handle the difference in XML
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Display a scrollable list of news articles
☑ Get articles endpoint with pagination
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Provide the option to filter news articles by category (such as UK News and Technology news), where this information is available
☑ *Get /articles endpoint has query params for category and provider.
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Show a single news article on screen, using an HTML display
☑ Get /article by ID endpoint with richer article object that includes the content of the article
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Provide the option to share news articles via email and/or social networks
☐ There is a url on the article object and GET article endpoint. But I'm not sure if that is the requirement here...
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Display a thumbnail of each article in the list of articles
☑ There were no images on the items. I added the news providers logo as the image.
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Present news articles in the order in which they are published
☑ Sorting by published date done at the DB level. I have added an index to the published date
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Allow the selection of different sources of news by category and provider
☑ Get articles endpoint has query params for category and provider. In the interests of delivering the API I have opted for the DB solution. The ideal solution might be to store the data and use Elastic Search which is great for searching data.
In terms of an API, the client wants it to be able to support the mobile app with all of the above functionality. They have not specified how the API should be constructed, nor have they defined any contracts. We are expected to do this and document it accordingly. Because we don't know where the client is actually going to source their news from, we need to be flexible about what feeds they want to use. They have told us to use at least one of the following news feeds to read this data from, but they want to be able to change this at any time:
- http://feeds.bbci.co.uk/news/uk/rss.xml (BBC News UK)
- http://feeds.bbci.co.uk/news/technology/rss.xml (BBC News Technology)
- http://feeds.reuters.com/reuters/UKdomesticNews?format=xml (Reuters UK)
- http://feeds.reuters.com/reuters/technologyNews?format=xml (Reuters Technology)
- Clear separation of data and endpoints
- Provide endpoints that are able to serve the usage patterns for the mobile app, as described above
- All endpoints must be RESTful
- SOLID principles
- Ability to create simple, meaningful contracts/interfaces for each appfunction
- Secure practices, good sanity checking and stability
- Ability to store data, such as the news feed locations
- Bonus: Adopt a microservices architecture to provide resilience and scalability
- Bonus: Use a third-party API provider to leverage any functionality
- Bonus: Provide caching in the API to allow for faster response times
http://localhost:8000/news?offset=0&pageSize=10&provider=reuters&category=technologyNews
News summaries in a list with pagination.
{
"articles": [
{
"id": 1,
"title": "SoftBank mulls bringing 40 companies to Brazil",
"category": "technologyNews",
"urlToImage": "https://www.reuters.com/resources_v2/images/reuters125.png",
"date": "2019-09-21T21:00:34+01:00",
"provider": "reuters"
},
{
"id": 2,
"title": "Huawei to join forces with China Mobile to bid for Brazil's Oi: report",
"category": "technologyNews",
"urlToImage": "https://www.reuters.com/resources_v2/images/reuters125.png",
"date": "2019-09-21T15:25:20+01:00",
"provider": "reuters"
},
{
"id": 3,
"title": "U.S. trade regulators approve some Apple tariff exemptions amid broader reprieve",
"category": "technologyNews",
"urlToImage": "https://www.reuters.com/resources_v2/images/reuters125.png",
"date": "2019-09-21T02:42:59+01:00",
"provider": "reuters"
},
{
"id": 4,
"title": "Facebook suspends tens of thousands of apps in response to Cambridge Analytica row",
"category": "technologyNews",
"urlToImage": "https://www.reuters.com/resources_v2/images/reuters125.png",
"date": "2019-09-21T02:08:17+01:00",
"provider": "reuters"
},
{
"id": 5,
"title": "Few U.S. lawmakers hit 'like' button after Facebook CEO visits Capitol Hill",
"category": "technologyNews",
"urlToImage": "https://www.reuters.com/resources_v2/images/reuters125.png",
"date": "2019-09-20T22:21:53+01:00",
"provider": "reuters"
}
],
"pageSize": 5,
"offSet": 0,
"totalRecords": 91
}
pageSize number of articles in the response (maximum 300 articles) offSet number of articles to offset (maximum 300 articles) category query by category provider query by news provider
Get the article by ID. Returns a richer article model for viewing per article in HTML.
{
"id": 1,
"title": "SoftBank mulls bringing 40 companies to Brazil",
"category": "technologyNews",
"urlToImage": "https://www.reuters.com/resources_v2/images/reuters125.png",
"date": "2019-09-21T21:00:34+01:00",
"provider": "reuters",
"url": "http://feeds.reuters.com/~r/reuters/technologyNews/~3/Vlo31M2hAvo/softbank-mulls-bringing-40-companies-to-brazil-idUSKBN1W52G2",
"description": "Japan's SoftBank Group Corp is considering bringing around 40 companies with high growth potential to Brazil and expects to announce a large investment in the country in around two weeks' time, the group's head in Brazil, André Maciel, said on Friday.<div class=\"feedflare\">\n<a href=\"http://feeds.reuters.com/~ff/reuters/technologyNews?a=Vlo31M2hAvo:CfWsZZzm3N4:yIl2AUoC8zA\"><img src=\"http://feeds.feedburner.com/~ff/reuters/technologyNews?d=yIl2AUoC8zA\" border=\"0\"></img></a> <a href=\"http://feeds.reuters.com/~ff/reuters/technologyNews?a=Vlo31M2hAvo:CfWsZZzm3N4:V_sGLiPBpWU\"><img src=\"http://feeds.feedburner.com/~ff/reuters/technologyNews?i=Vlo31M2hAvo:CfWsZZzm3N4:V_sGLiPBpWU\" border=\"0\"></img></a> <a href=\"http://feeds.reuters.com/~ff/reuters/technologyNews?a=Vlo31M2hAvo:CfWsZZzm3N4:-BTjWOF_DHI\"><img src=\"http://feeds.feedburner.com/~ff/reuters/technologyNews?i=Vlo31M2hAvo:CfWsZZzm3N4:-BTjWOF_DHI\" border=\"0\"></img></a>\n</div><img src=\"http://feeds.feedburner.com/~r/reuters/technologyNews/~4/Vlo31M2hAvo\" height=\"1\" width=\"1\" alt=\"\"/>"
}
Request the news from 3rd party sources and load the articles into the DB. This Would not be part of the public API...