Pass in schema as an option

README.md

@@ -9,7 +9,8 @@ A friendlier Ruby client for consuming GraphQL-based APIs. Built on top of your
 
 - [Installation](#installation)
 - [Usage](#usage)
-  - [Schema storing and loading on disk](#schema-storing-and-loading-on-disk)
+  - [Schema Storing and Loading on Disk](#schema-storing-and-loading-on-disk)
+  - [Preloading Schema Once](#preloading-schema-once)
   - [Error Handling](#error-handling)
   - [Executing Parameterized Queries and Mutations](#executing-parameterized-queries-and-mutations)
   - [Parse and Execute Queries Separately](#parse-and-execute-queries-separately)
@@ -140,6 +141,30 @@ client = Client.new(url, schema_path: 'config/your_graphql_schema.json')
 client.schema.dump! # you only need to call this when graphql schema changes
 ```
 
+### Preloading schema once
+
+Even if caching the schema on disk, instantiating `Graphlient::Client` often can be both time and memory intensive due to reading in the schema for each instance. This is especially true if the schema is a large file. To get around these performance issues, instantiate your schema once and pass it in as a configuration option.
+
+One time in an initializer
+
+```ruby
+$schema = Graphlient::Schema.new(
+  'https://graphql.foo.com/graphql', 'lib/graphql_schema_foo.json'
+)
+```
+
+Pass in each time you initialize a client
+
+```
+client = Graphlient::Client.new(
+  $schema.http,
+  $schema: schema,
+  headers: {
+    'Authorization' => 'Bearer 123',
+  }
+)
+```
+
 ### Error Handling
 
 Unlike graphql-client, Graphlient will always raise an exception unless the query has succeeded.

lib/graphlient/client.rb

@@ -2,9 +2,12 @@ module Graphlient
   class Client
     attr_accessor :uri, :options
 
+    class InvalidConfigurationError < StandardError; end
+
     def initialize(url, options = {}, &_block)
       @url = url
       @options = options.dup
+      raise_error_if_invalid_configuration!
       yield self if block_given?
     end
 
@@ -51,11 +54,17 @@ def http(&block)
     end
 
     def schema
-      @schema ||= Graphlient::Schema.new(http, schema_path)
+      @schema ||= options[:schema] || Graphlient::Schema.new(http, schema_path)
     end
 
     private
 
+    def raise_error_if_invalid_configuration!
+      if options.key?(:schema_path) && options.key?(:schema)
+        raise InvalidConfigurationError, 'schema_path and schema cannot both be provided'
+      end
+    end
+
     def schema_path
       return options[:schema_path].to_s if options[:schema_path]
     end

spec/graphlient/client_schema_spec.rb

@@ -51,5 +51,25 @@
         expect(client.schema.path).to eq 'config/schema.json'
       end
     end
+
+    context 'when preloaded schema is provided' do
+      let(:schema) { Graphlient::Schema.new(url, 'spec/support/fixtures/invoice_api.json') }
+      let(:client) { described_class.new(url, schema: schema) }
+
+      it 'returns the passed in schema' do
+        expect(client.schema).not_to be_nil
+        expect(client.schema).to eq(schema)
+      end
+    end
+
+    context 'when and a schema and a schema path are provided' do
+      let(:schema) { Graphlient::Schema.new(url, 'spec/support/fixtures/invoice_api.json') }
+      let(:client) { described_class.new(url, schema: schema, schema_path: 'spec/support/fixtures/invoice_api.json') }
+
+      it 'raises an invalid configuration error' do
+        expect { client }.to raise_error(Graphlient::Client::InvalidConfigurationError,
+          /schema_path and schema cannot both be provided/)
+      end
+    end
   end
 end