Rails按任意列查询

Question

In my Rails API / Angular app, I want to be able to search Rails tables using field values. I currently have this code below working, which allows searching the users table by email id, and it returns the users record as JSON.

api/controllers/users_controller.rb

def query  # by email
  queried_user = User.where(email: params[:email]).first
  if !queried_user.nil?
    render json: queried_user, root: false
  else
    render json: {error: 'Does not exist'}, status: :not_found
  end
end

config/routes.rb

get 'api/users/:id/query' => 'api/users#query'

Example url

http://0.0.0.0:8080/api/users/1/query?email=testuser1@example.com

Example returned JSON

{"id":14,"title":"Dr.","first_name":"John","last_name":"Smith","email":"testuser1@example.com","job_title":"Head Bioligist","organisation":"NIH","phone_office":null,"city":null,"country":null,"approved":true,"admin":false,"template":false}

This is all working fine at present, but there are two issues I cannot resolve.

1. I would like the url to not contain an :id I find when I leave the id out of the url, Rails treats the query parameter as the id. I can made it work by hard-coding a fake id, but it doesn't seem like the right answer to me.

2. I would like to pass an abitary param hash to the query method. It should map the columns based on the hash contents.

if params = {email: 'testuser1@example.com'} then it should work as now, but other desired options might be:

{job_title: 'Manager'}
{city: 'LA', last_name: 'Smith'}

I expect I will change this code, but don't know how to pass arbitrary elements to the where.

queried_user = User.where(email: params[:email])

Answer 1

The where method can accept a hash, therefore you can pass the param hash containing the condition for the query. Just note only equality and range conditions can be used when passing a hash to the where method. Just be sure that in terms of security of your application you are covered. example:

queried_user = User.where(params[:user])

To get rid of the :id in your routes file define a new route similar to this:

match 'api/users/query', to: 'users#query', as 'user_search'

and then use the 'user_search_path' for sending the search to the query action of the users controller.