WIP Ruby GraphQL demo app

ruby/rails8-sidekiq/app/Gemfile

@@ -16,6 +16,7 @@ gem "turbo-rails"
 gem "stimulus-rails"
 # Build JSON APIs with ease [https://github.com/rails/jbuilder]
 gem "jbuilder"
+gem "graphql"
 
 # Use Active Model has_secure_password [https://guides.rubyonrails.org/active_model_basics.html#securepassword]
 # gem "bcrypt", "~> 3.1.7"

ruby/rails8-sidekiq/app/Gemfile.lock

@@ -1,7 +1,7 @@
 PATH
   remote: /integration
   specs:
-    appsignal (4.7.5)
+    appsignal (4.8.4)
       logger
       rack (>= 2.0.0)
 
@@ -116,11 +116,16 @@ GEM
     erubi (1.13.1)
     et-orbi (1.2.11)
       tzinfo
+    fiber-storage (1.0.1)
     fugit (1.11.1)
       et-orbi (~> 1, >= 1.2.11)
       raabro (~> 1.4)
     globalid (1.2.1)
       activesupport (>= 6.1)
+    graphql (2.6.1)
+      base64
+      fiber-storage
+      logger
     i18n (1.14.7)
       concurrent-ruby (~> 1.0)
     importmap-rails (2.0.3)
@@ -394,6 +399,7 @@ DEPENDENCIES
   brakeman
   capybara
   debug
+  graphql
   importmap-rails
   jbuilder
   kamal

ruby/rails8-sidekiq/app/app/controllers/examples_controller.rb

@@ -1,3 +1,6 @@
+require "net/http"
+require "json"
+
 class ReportError < StandardError; end
 
 class ExamplesController < ApplicationController
@@ -48,6 +51,115 @@ def error_reporter
     render :html => "An error has been reported through the Rails error reporter"
   end
 
+  def graphql_demo
+    query = <<~GRAPHQL
+      query CustomerOverview($customerId: ID!, $ordersLimit: Int!, $status: OrderStatus) {
+        customer(id: $customerId) {
+          id
+          fullName
+          tier
+          loyaltyPoints
+          primaryAddress {
+            city
+            country
+          }
+          orders(limit: $ordersLimit, status: $status) {
+            id
+            orderNumber
+            status
+            total {
+              amount
+              currency
+            }
+            lineItems {
+              sku
+              quantity
+              totalPrice {
+                amount
+                currency
+              }
+              product {
+                id
+                name
+                category
+                supplier {
+                  name
+                  region
+                }
+              }
+            }
+            shipment {
+              carrier
+              trackingNumber
+              estimatedDeliveryOn
+            }
+          }
+        }
+      }
+
+      query WarehouseOperations($warehouseId: ID!, $productQuery: String!, $limit: Int!) {
+        warehouse(id: $warehouseId) {
+          id
+          code
+          name
+          address {
+            city
+            country
+          }
+          inventorySnapshots {
+            productId
+            available
+            reserved
+            reorderThreshold
+            onHand
+          }
+        }
+        searchProducts(query: $productQuery, limit: $limit) {
+          id
+          name
+          category
+          unitPrice {
+            amount
+            currency
+          }
+          supplier {
+            id
+            name
+          }
+        }
+      }
+    GRAPHQL
+
+    batch_payload = [
+      {
+        query: query,
+        operationName: "CustomerOverview",
+        variables: {
+          customerId: "cust-001",
+          ordersLimit: 2,
+          status: "SHIPPED"
+        }
+      },
+      {
+        query: query,
+        operationName: "WarehouseOperations",
+        variables: {
+          warehouseId: "wh-east-1",
+          productQuery: "pro",
+          limit: 3
+        }
+      }
+    ]
+
+    response = post_graphql_request(batch_payload)
+
+    render json: {
+      description: "Batch request with multiple operationName values in one HTTP request",
+      request_payload: batch_payload,
+      graphql_response: response[:body]
+    }, status: response[:status]
+  end
+
   def queries
     user_count = User.count
     User.destroy_all if user_count > 10_000
@@ -57,6 +169,36 @@ def queries
     end
     @users = User.all
   end
+
+  private
+
+  def post_graphql_request(payload)
+    uri = URI.parse("#{request.base_url}/graphql")
+    http = Net::HTTP.new(uri.host, uri.port)
+    http.use_ssl = uri.scheme == "https"
+
+    request = Net::HTTP::Post.new(uri.request_uri)
+    request["Content-Type"] = "application/json"
+    request.body = payload.to_json
+
+    response = http.request(request)
+    {
+      status: response.code.to_i,
+      body: JSON.parse(response.body)
+    }
+  rescue JSON::ParserError
+    {
+      status: :bad_gateway,
+      body: {
+        errors: [
+          {
+            message: "GraphQL endpoint returned invalid JSON",
+            raw_body: response&.body
+          }
+        ]
+      }
+    }
+  end
 end
 
 class CauseCauser

ruby/rails8-sidekiq/app/app/controllers/graphql_controller.rb

@@ -0,0 +1,72 @@
+class GraphqlController < ApplicationController
+  skip_forgery_protection
+
+  def execute
+    if batch_request?
+      render json: ExampleAppSchema.multiplex(multiplex_payload)
+    else
+      render json: ExampleAppSchema.execute(
+        params[:query],
+        variables: prepare_variables(params[:variables]),
+        operation_name: params[:operationName],
+        context: graphql_context
+      )
+    end
+  rescue StandardError => e
+    render json: { errors: [{ message: e.message }] }, status: :unprocessable_entity
+  ensure
+    transaction_name = params[:operationName] || "Unknown"
+    puts "!!! controller transaction name: #{transaction_name}"
+    Appsignal::Transaction.current.set_action(transaction_name)
+  end
+
+  private
+
+  def batch_request?
+    params[:_json].is_a?(Array)
+  end
+
+  def multiplex_payload
+    params[:_json].map do |entry|
+      payload = normalize_entry(entry)
+      puts "!!! controller multiplex action name: #{payload["operationName"] || payload[:operationName]}"
+      {
+        query: payload["query"] || payload[:query],
+        variables: prepare_variables(payload["variables"] || payload[:variables]),
+        operation_name: payload["operationName"] || payload[:operationName],
+        context: graphql_context
+      }
+    end
+  end
+
+  def normalize_entry(entry)
+    if entry.respond_to?(:to_unsafe_h)
+      entry.to_unsafe_h
+    else
+      entry.to_h
+    end
+  end
+
+  def graphql_context
+    {
+      request_id: request.request_id,
+      remote_ip: request.remote_ip,
+      :set_appsignal_action_name => true
+    }
+  end
+
+  def prepare_variables(variables_param)
+    case variables_param
+    when String
+      variables_param.present? ? prepare_variables(JSON.parse(variables_param)) : {}
+    when ActionController::Parameters
+      variables_param.to_unsafe_h
+    when Hash
+      variables_param
+    when nil
+      {}
+    else
+      raise ArgumentError, "Unexpected variables format: #{variables_param.class}"
+    end
+  end
+end

ruby/rails8-sidekiq/app/app/graphql/example_app_schema.rb

@@ -0,0 +1,4 @@
+class ExampleAppSchema < GraphQL::Schema
+  trace_with(GraphQL::Tracing::AppsignalTrace)
+  query Types::QueryType
+end