graphql-pagination-example.rb

require 'uri'
require 'net/http'
require 'net/https'
require 'json'

GRAPHQL_API_KEY = ENV.fetch("GRAPHQL_API_KEY")

def perform_graphql_query(query, variables)
  # This is our Buildkite GraphQL Endpoint.
  uri = URI.parse("https://graphql.buildkite.com/v1")

  # Create an instance of the HTTP class so we can make a HTTP request.
  https = Net::HTTP.new(uri.host, uri.port)
  https.use_ssl = true

  # Setup our actual request. Authentication is done via a Buildkite API key with
  # the GraphQL scope enabled.
  req = Net::HTTP::Post.new(uri.path, { 'Content-Type' => 'application/json', 'Authorization' => "Bearer #{GRAPHQL_API_KEY}" })
  req.body = JSON.generate(query: query, variables: variables)

  # Perform the request and return the response.
  https.request(req)
end

query = <<~GRAPHQL
  query GetPipelines($organizationSlug: ID!, $after: String, $pageSize: Int) {
    organization(slug: $organizationSlug) {
      pipelines(first: $pageSize, after: $after) {
	pageInfo {
	  hasNextPage
	}
	edges {
	  cursor
	  node {
	    name
	    builds(first: 1, branch:"%default") {
	      edges {
		node {
		  state
		}
	      }
	    }
	  }
	}
      }
    }
  }
GRAPHQL

# Get the organization slug from an environment variable
org_slug = ENV.fetch("ORGANIZATION_SLUG")

# Setup the first set of variables we'll send to GraphQL
variables = { organizationSlug: org_slug, pageSize: 5 }

# `has_next_page` will stay true as long as the `pageInfo.hasNextPage` variable is
# true in the GraphQL response
has_next_page = true

while has_next_page
  response = perform_graphql_query(query, variables)

  # Make sure the GraphQL response is all good
  if response.code.to_i != 200
    raise "GraphQL query failed: #{response.code} #{response.message} #{response.body}"
  end

  # Parse the JSON from the GraphQL query
  json = JSON.parse(response.body)

  # Figure out if there's another page of info. If this is false, the
  # `has_next_page` will become false and the loop will stop
  has_next_page = json["data"]["organization"]["pipelines"]["pageInfo"]["hasNextPage"]

  # If there's still another page, grab the last cursor in the list, and add it
  # to the variables that we'll send in the next iteration
  if has_next_page
    variables[:after] = json["data"]["organization"]["pipelines"]["edges"].last["cursor"]
  end

  # Just show the output
  puts response.body
  puts "-------------------------"
end

puts "\nAll done! No more pipelines to paginate through!"