refactor: optimize totalCount compute for X-Total-Count header

[ricfio]

computes totalCount without extra query execution when possible

[mcollina]

lgtm

[marcopiraccini]

@ricfio LGTM, just please make sure that we have a test for this case

[ricfio]

@ricfio LGTM, just please make sure that we have a test for this case

I tried adding some extra tests, but he was sure it was a good idea, so I preferred not to add them right now.

If you want I could add these:

  {
    const url = '/posts?offset=1&totalCount=true'
    const res = await app.inject({
      method: 'GET',
      url: url
    })
    equal(res.statusCode, 200, `${url} status code`)
    equal(res.headers['x-total-count'], posts.length, `${url} x-total-count`)
    same(res.json(), posts.map((p, i) => {
      return { ...p, id: i + 1 + '' }
    }).slice(1, 4), `${url} response`)
  }

  {
    const url = '/posts?limit=99&offset=0&totalCount=true'
    const res = await app.inject({
      method: 'GET',
      url: url
    })
    equal(res.statusCode, 200, `${url} status code`)
    equal(res.headers['x-total-count'], posts.length, `${url} x-total-count`)
    same(res.json(), posts.map((p, i) => {
      return { ...p, id: i + 1 + '' }
    }).slice(0, 4), `${url} response`)
  }

  {
    const url = '/posts?limit=99&offset=2&totalCount=true'
    const res = await app.inject({
      method: 'GET',
      url: url
    })
    equal(res.statusCode, 200, `${url} status code`)
    equal(res.headers['x-total-count'], posts.length, `${url} x-total-count`)
    same(res.json(), posts.map((p, i) => {
      return { ...p, id: i + 1 + '' }
    }).slice(2, 4), `${url} response`)
  }

  {
    const url = '/posts?limit=2&offset=99&totalCount=true'
    const res = await app.inject({
      method: 'GET',
      url: url
    })
    equal(res.statusCode, 200, `${url} status code`)
    equal(res.headers['x-total-count'], posts.length, `${url} x-total-count`)
    same(res.json(), [], `${url} response`)
  }

[mcollina]

Add them ;)

[ricfio]

I added after the test /posts?totalCount=true (temporarly removed) in other position with a later commit.

[ricfio]

please see the changes history commit by commit because I have done some tests refactor before the last commit:

• test: add the extra tests to cover totalCount compute optimization cases

[marcopiraccini]

OK!

[leorossi]

LGTM