REST API - Eager loading nested resources

Question

I would like to know if I am correctly eager loading nested resources in my API.

In my app, companies can have many technologies, and tools. The relationship is stored in the join tables companies_technologies and companies_tools.

At an endpoint /companies, I would like to return all the companies and their technologies and tools like the following:

[
  {
    company_name: 'company_1',
    ...
    technologies: [
      {...},
      ...,
      {...}
    ],
    tools: [
      {...},
      ...,
      {...}
    ]
  },
  ..., 
  {
    company_name: 'company_n',
    ...
  }
]

To return 30 companies, I end up doing 61 queries.

One query to get at most 30 companies (1 query)
Loop through the companies to get the technologies for each of them. (30 queries)
Loop through the companies to get the tools for each of them. (30 queries)

Then I build the response and send it back to the client.

The response time is very high even with indices on all foreign keys. Is doing that many query unavoidable for my API design, or is there an alternative approach?

What is the likelihood that, for any given endpoint request, you are going to need all of that data? — Robert Harvey
– Robert Harvey, Commented Aug 18, 2016 at 0:40
@RobertHarvey Returning all those data makes it easier to render on the client side. Supposing the data is needed, is doing that many query unavoidable? — mc9
– mc9, Commented Aug 18, 2016 at 0:45

Robert Harvey · Accepted Answer · 2016-08-18 00:44:42Z

3

If you genuinely need all of that data for every request, you can almost certainly retrieve it with a single query having the appropriate joins, and then massage it into the appropriate JSON format. This will save you tons of processing time.

However, I suspect that your consumer doesn't always need all of that data. Consider providing options on the endpoint that allow them to request technologies and tools separately by company.

answered Aug 18, 2016 at 0:44

Robert Harvey

201k55 gold badges470 silver badges683 bronze badges

Add a comment |

Stack Exchange Network

REST API - Eager loading nested resources

1 Answer 1

Your Answer

Hot Network Questions

REST API - Eager loading nested resources

1 Answer 1

Your Answer

Sign up or log in

Post as a guest

Related

Hot Network Questions