Differences

This shows you the differences between two versions of the page.

--- learnexa_graphql_api [2019/04/19 06:59]
182.72.26.6 created
+++ learnexa_graphql_api [2019/08/08 05:29] (current)
182.72.26.6 [Learnexa GrapphQL API]
@@ Line 1: / Line 1: @@
-====== Learnexa GrapphQL API ======
+====== Learnexa GraphQL API ======
-===== Objective =====
+===== Implementation =====
 ) Create new Ruby on Rails application
@@ Line 27: / Line 27: @@
 </code>
-) Start rails server
+) Add existing learnexa db in database.yml file
-Open localhost:3000/graphiql
+<code>
+default: &default
+  adapter: mysql2
+  encoding: utf8
+  pool: <%= ENV.fetch("RAILS_MAX_THREADS") { 5 } %>
+  username: root
+  password: root
+  socket: /var/run/mysqld/mysqld.sock
+development:
+  <<: *default
+  database: learnexa_db
+</code>
+) Recreate all learnexa models(Sample code given below):
+app/models/course.rb
+<code>
+class Course < ApplicationRecord
+  has_many :course_contents, -> { order :position }, :dependent => :destroy
+  has_many :contents, :through => :course_contents
+end
+</code>
+app/models/course_content.rb
+<code>
+class CourseContent < ApplicationRecord
+  belongs_to :course
+  belongs_to :content
+end
+</code>
+app/models/content.rb
+<code>
+class Content < ApplicationRecord
+  has_many :course_contents, :dependent => :destroy
+  has_many :courses, :through => :course_contents, :class_name => 'Course', :source => :course
+end
+</code>
+) Create course_type.rb file in app/grapghql/types folder:
+<code>
+module Types
+  class CourseType < BaseObject
+    field :id, ID, null: false
+    field :title, String, null: false
+    field :course_contents, [Types::CourseContentType], null: false
+    field :contents, [Types::ContentType], null: false
+  end
+end
+</code>
+) Also create content_type.rb, course_content_type.rb files
+content_type.rb
+<code>
+module Types
+  class ContentType < BaseObject
+    field :id, ID, null: false
+    field :title, String, null: false
+    field :created_at, String, null: false
+    field :updated_at, String, null: false
+    field :course_contents, [Types::CourseContentType], null: false
+  end
+end
+</code>
+course_content_type.rb
+<code>
+module Types
+  class CourseContentType < BaseObject
+    field :id, ID, null: false
+    field :maximum_attempts, Integer, null: false
+    field :course, Types::CourseType, null: false
+  end
+end
+</code>
+) In app/grapghql/types/quert_type.rb files add the query methods
+<code>
+module Types
+  class QueryType < Types::BaseObject
+    field :all_courses, [Types::CourseType], null: false
+    field :get_course, CourseType, null: false do
+      argument :id, ID, required: true
+    end
+    def all_courses
+      Course.all
+    end
+    def get_course(id:)
+      Course.find(id)
+    end
+    def get_content(id:)
+      Content.find(id)
+    end
+  end
+end
+</code>
+) Build a schema with QueryType as the query entry point:
+app/grapghql/learnexa_api_schema.rb
+<code>
+class LearnexaApiSchema < GraphQL::Schema
+  mutation Types::MutationType
+  query Types::QueryType
+end
+</code>
+) Start rails server
+Open localhost:3000/graphiql to run the queries and fetch records.
+) Sample API curl call:
+Example 1
+Request
+<code>
+curl \
+  -X POST \
+  -H "Content-Type: application/json" \
+  --data '{ "query": "{ allCourses { title } }" }' \
+  http://localhost:3000/graphql
+</code>
+Response
+<code>
+{"data":{"allCourses":[{"title":"ds"},
+  {"title":"Agile Query-Driven Data Modeling for NoSQL"},
+  {"title":"Practitioner’s Perspective on the Enterprise Data Model"},
+  {"title":"A Foundation For All Things Process: Modeling, Design and Architecture"},
+  {"title":"Human-Centered Design"},{"title":"Application Development with Python and Flask"}]}
+}
+</code>
+Example 2
+Request query:
+<code>
+{
+  getContent(id: 3234) {
+    title
+    courseContents {
+      maximumAttempts
+    }
+  }
+}
+</code>
+Response:
+<code>
+{
+  "data": {
+    "getContent": {
+      "title": "Intermediate System to Intermediate System (IS-IS) Routing Protocol",
+      "courseContents": [
+        {
+          "maximumAttempts": 1
+        }
+      ]
+    }
+  }
+}
+</code>
+Example 3
+Request:
+<code>
+{
+  getCourse(id: 2) {
+    title
+    contents {
+      title
+    }
+  }
+}
+</code>
+Response:
+<code>
+{
+  "data": {
+    "getCourse": {
+      "title": "Practitioner’s Perspective on the Enterprise Data Model",
+      "contents": [
+        {
+          "title": "Practitioner’s Perspective on the Enterprise Data Model"
+        }
+      ]
+    }
+  }
+}
+</code>
+===== API Setup Server =====
+) Download the following zip file
+{{learnexa_api.zip}}
+) Run "bundle install"
+) Change database name in "database.yml". Point it to current devlep01 server database.
+) Start rails server in the working directory "rails s"

DokuWiki

Site Tools

Differences

Page Tools