How to use OpenAPI3 for API developer (RubyKaigi 2019)

7fefbc0ddbb13f3bfde050f85acfa0c4?s=47 ota42y
April 18, 2019

How to use OpenAPI3 for API developer (RubyKaigi 2019)

7fefbc0ddbb13f3bfde050f85acfa0c4?s=128

ota42y

April 18, 2019
Tweet

Transcript

  1. How to use OpenAPI 3 for API developer RubyKaigi 2019

    ota42y (FiNC Technologies)
  2. Today’s Topic • Introduce OpenAPI 3 and explain why it

    is necessary • The OpenAPI 3 specification • How to use OpenAPI 3 • Request / response validation • A story about how to implement OpenAPI 3 feature • Other OpenAPI 3 tools
  3. about me • @ota42y (github/twitter) • Server side engineer at

    FiNC Technologies • I maintain request/response validation gem using OpenAPI 3
  4. 2F

  5. Introduce OpenAPI 3 and explain why it is necessary

  6. OpenAPI 3 • programming language-agnostic definition for REST API •

    OpenAPI 3 means OpenAPI specification version 3 • previously known as Swagger so Swagger 2 == OpenAPI 2 https://www.openapis.org/
  7. Definition of OpenAPI 3 • It’s machine-readable API definition rule

    • Definition of OpenAPI 3 is described in YAML or JSON formats • We can use it as interactive document generation, validation, mock-server, client library, etc…(I’ll talk about it later)
  8. Sometimes the machine-readable API schema is important • When we

    create many APIs • When we want to do schema-first development • etc…
  9. When we create many APIs • Backend API server for

    iOS/Android/Web(SPA) • We have many JSON APIs
 (We use microservices architecture so 1000 over endpoints ) • API schema is very important for interface documentation
  10. Schema first development • Schema first development • Define API

    schema • Client-side and server-side implement according it • Integration test • Without Schema first development, 
 we can’t start client-side implement until server side implement finished Reference: RubyKaigi 2017 API Development in 2017 https://www.youtube.com/watch?v=a28jJ62ZfZM Rails Developers Meetup 2019: 
 https://speakerdeck.com/aeroastro/rails-meets-protocol-buffers-for-schema-first-development
  11. Definition and implementation must be always same • If there

    are difference we can’t trust API schema • Even if we passed unit test, we gets bug on integration test • But it’s difficult to avoid making mistakes
  12. The machine-readable API schema is important • We can find

    mistakes API automatically using the schema • So always the schema and definition is matched • We can use schema to generate human-readable docs, client library, etc…
  13. OpenAPI 3

  14. OpenAPI is one of the definition method • JSON Hyper-Schema

    • It defines hypermedia specifications, and it can also be used to define REST API too • GraphQL • Query language and runtime • The response can be specified in the query sent from the client
  15. OpenAPI is one of the definition method • gRPC •

    RPC framework using protocol buffers and HTTP/2 • It generates code from interface definition and do almost all communication processing
  16. OpenAPI extends REST API • OpenAPI is just a YAML/JSON

    rule • Actual processing is just REST API • OpenAPI 3 takes full advantage of existing RESTful frameworks and insights • Since REST is a web best practice at the time, various mechanisms such as HTTP cache, monitoring system can also be used
  17. The OpenAPI 3 specification

  18. Example API get "/apps" do content_type :json # page should

    be Integer page = params["page"] [page, (page*10)].map(&:to_s).to_json end
  19. get "/apps" do content_type :json # page should be Integer

    page = params["page"] [page, (page*10)].map(&:to_s).to_json end • GET /apps returns application/json Example API
  20. get "/apps" do content_type :json # page should be Integer

    page = params["page"].to_i [page, (page*10)].map(&:to_s).to_json end • GET /apps returns application/json • This API requires `page` parameter and must be Integer Example API
  21. get "/apps" do content_type :json # page should be Integer

    page = params["page"].to_i [page, (page*10)].map(&:to_s).to_json end • GET /apps returns application/json • This API requires `page` parameter and must be Integer • Succeed response includes string array Example API
  22. Example API to OpenAPI 3 definition openapi: 3.0.0 info: title:

    Sample API version: 0.1.0 paths: "/apps": get: parameters: - name: page in: query required: true schema: type: integer responses: '200': description: example content: 'application/json': schema: type: array items: type: string
  23. Example API to OpenAPI 3 definition • GET /apps openapi:

    3.0.0 info: title: Sample API version: 0.1.0 paths: "/apps": get: parameters: - name: page in: query required: true schema: type: integer responses: '200': description: example content: 'application/json': schema: type: array items: type: string
  24. Example API to OpenAPI 3 definition • GET /apps returns

    application/json openapi: 3.0.0 info: title: Sample API version: 0.1.0 paths: "/apps": get: parameters: - name: page in: query required: true schema: type: integer responses: '200': description: example content: 'application/json': schema: type: array items: type: string
  25. Example API to OpenAPI 3 definition • GET /apps returns

    application/json • `page` parameter required and it’s integer openapi: 3.0.0 info: title: Sample API version: 0.1.0 paths: "/apps": get: parameters: - name: page in: query required: true schema: type: integer responses: '200': description: example content: 'application/json': schema: type: array items: type: string
  26. Example API to OpenAPI 3 definition • GET /apps returns

    application/json • `page` parameter required and it’s integer • Succeed response includes string array openapi: 3.0.0 info: title: Sample API version: 0.1.0 paths: "/apps": get: parameters: - name: page in: query required: true schema: type: integer responses: '200': description: example content: 'application/json': schema: type: array items: type: string
  27. Example API to OpenAPI 3 definition • GET /apps returns

    application/json • `page` parameter required and it’s integer • Succeed response includes string array openapi: 3.0.0 info: title: Sample API version: 0.1.0 paths: "/apps": get: parameters: - name: page in: query required: true schema: type: integer responses: '200': description: example content: 'application/json': schema: type: array items: type: string
  28. OpenAPI 3 structure JOGP QBUIT TFSWFST DPNQPOFOUT TFDVSJUZ UBHT FYUFSOBM%PDT

    required
  29. OpenAPI 3 structure JOGP QBUIT TFSWFST DPNQPOFOUT TFDVSJUZ UBHT FYUFSOBM%PDT

    required Metadata for this definition API definitions Target server setting Schema objects Security settings Tags External document url
  30. OpenAPI 3 structure JOGP QBUIT TFSWFST DPNQPOFOUT TFDVSJUZ UBHT FYUFSOBM%PDT

    required Metadata for this definition API definitions Target server setting Schema objects Security settings Tags External document url
  31. openapi: 3.0.0 info: title: Sample API version: 0.1.0 paths: "/apps":

    get: parameters: - name: page in: query required: true schema: type: integer responses: '200': description: example content: 'application/json': schema: type: array items: type: string Paths Object • API definitions are written in this section • There is path string key and 
 Path Item Object • We can write definition in Path Item Object Path string Path Item Object
  32. openapi: 3.0.0 info: title: Sample API version: 0.1.0 paths: "/apps":

    get: parameters: - name: page in: query required: true schema: type: integer responses: '200': description: example content: 'application/json': schema: type: array items: type: string Path Item Object • Define request/response parameter 
 per HTTP method Path Item Object
  33. Path Item Object • Define request/response parameter 
 per HTTP

    method • We can define request parameter openapi: 3.0.0 info: title: Sample API version: 0.1.0 paths: "/apps": get: parameters: - name: page in: query required: true schema: type: integer responses: '200': description: example content: 'application/json': schema: type: array items: type: string
  34. Path Item Object • Define request/response parameter 
 per HTTP

    method • We can define request parameter and 
 response parameter schema openapi: 3.0.0 info: title: Sample API version: 0.1.0 paths: "/apps": get: parameters: - name: page in: query required: true schema: type: integer responses: '200': description: example content: 'application/json': schema: type: array items: type: string
  35. OpenAPI 3 structure JOGP QBUIT TFSWFST DPNQPOFOUT TFDVSJUZ UBHT FYUFSOBM%PDT

    required Metadata for this definition API definitions Target server setting Schema objects Security settings Tags External document url
  36. Security Scheme Object • We can define security schema for

    all API or specific API
  37. Security Scheme Object • We can define security schema for

    all API or specific API • We can use HTTP authentication type: http scheme: basic type: http scheme: bearer bearerFormat: JWT JWT basic
  38. Security Scheme Object • We can define security schema for

    all API or specific API • We can use HTTP authentication, API key (like header, query) type: http scheme: basic type: apiKey name: api_key in: header type: http scheme: bearer bearerFormat: JWT JWT API key basic
  39. Security Scheme Object • We can define security schema for

    all API or specific API • We can use HTTP authentication, API key (like header, query), 
 OAuth2, OpenID Connect type: http scheme: basic type: apiKey name: api_key in: header type: http scheme: bearer bearerFormat: JWT JWT API key basic type: oauth2 flows: implicit: authorizationUrl: https://example.co... scopes: write:pets: modify pets read:pets: read your pets OAuth2
  40. OpenAPI 3 structure JOGP QBUIT TFSWFST DPNQPOFOUT TFDVSJUZ UBHT FYUFSOBM%PDT

    required openapi: 3.0.0 info: title: Sample API version: 0.1.0 paths: "/apps": get: parameters: - name: page in: query required: true schema: type: integer responses: '200': description: example content: 'application/json': schema: type: array items: type: string
  41. How to use OpenAPI 3

  42. OpenAPI is definition • It’s just a rule in YAML/JSON

    file, so it alone does nothing • It is effective by combining it with peripheral tools • request/response validation, interactive document generation, mock-server, client library, etc…
  43. Request / Response validation
 using OpenAPI 3

  44. We need validation • We make mistakes when implementing the

    API
  45. We need validation • We make mistakes when implementing the

    API • OpenAPI is programming language-agnostic definition
  46. We need validation • We make mistakes when implementing the

    API • OpenAPI is programming language-agnostic definition • So we need a tool to check differences between implementation and definition
  47. We need validation • We make mistakes when implementing the

    API • OpenAPI is programming language-agnostic definition • So we need a tool to check differences between implementation and definition • This will ensure the credibility of the schema
  48. committee gem • Request/Response validation gem

  49. committee gem • Request/Response validation gem • This gem works

    as Rack middleware and performs validation if requested URL is in definition 3BDL
 "QQMJDBUJPO $MJFOU "QQMJDBUJPO Request validation Response validation committee
  50. Request validation using committee require "sinatra" require "committee" use Committee::Middleware::RequestValidation,

    schema_path: 'schema.yaml' use Committee::Middleware::ResponseValidation, schema_path: 'schema.yaml' get "/apps" do content_type :json # page should be Integer page = params["page"].to_i [page, (page*10)].map(&:to_s).to_json end
  51. require "sinatra" require "committee" use Committee::Middleware::RequestValidation, schema_path: 'schema.yaml' use Committee::Middleware::ResponseValidation,

    schema_path: 'schema.yaml' get "/apps" do content_type :json # page should be Integer page = params["page"].to_i [page, (page*10)].map(&:to_s).to_json end Request validation using committee committee returns error without `page` parameter % curl -X GET "http://localhost:4567/apps" {"id":"bad_request","message":"required parameters page not exist in #/paths/~1apps/get”}
  52. Request validation using committee % curl -X GET "http://localhost:4567/apps" {"id":"bad_request","message":"required

    parameters page not exist in #/paths/~1apps/get”} % curl -X GET "http://localhost:4567/apps?page=1" ["1","10"] When `page` parameter exists, get correct response require "sinatra" require "committee" use Committee::Middleware::RequestValidation, schema_path: 'schema.yaml' use Committee::Middleware::ResponseValidation, schema_path: 'schema.yaml' get "/apps" do content_type :json # page should be Integer page = params["page"].to_i [page, (page*10)].map(&:to_s).to_json end
  53. % curl -X GET "http://localhost:4567/apps?page=1" ["1","1111111111"] require "sinatra" require "committee"

    # use Committee::Middleware::RequestValidation, schema_path: 'schema.yaml' # use Committee::Middleware::ResponseValidation, schema_path: 'schema.yaml' get "/apps" do content_type :json # page should be Integer page = params["page"] [page, (page*10)].map(&:to_s).to_json end Coerce request parameter Normally, request parameters don’t have type and are always string
  54. % curl -X GET "http://localhost:4567/apps?page=1" ["1","10"] Coerce request parameter But

    committee converts class using definition type (optional feature) require "sinatra" require "committee" use Committee::Middleware::RequestValidation, schema_path: 'schema.yaml' use Committee::Middleware::ResponseValidation, schema_path: 'schema.yaml' get "/apps" do content_type :json # page should be Integer page = params["page"] [page, (page*10)].map(&:to_s).to_json end
  55. Coerce request body and other convert % curl -X POST

    -H "Content-Type: application/json" -d '{"measured_at":"2016-04-01T16:00:00+09:00"}' “http://localhost:4567/apps" {"class":"DateTime"} post: requestBody: content: application/json: schema: type: object properties: measured_at: type: string format: date-time responses: '201': description: no content content: 'application/json': schema: type: object properties: class: type: string • committee coerce parameter in request body • When string in date-time format, 
 committee converts it to DateTime class
  56. Response validation using committee require "sinatra" require "committee" use Committee::Middleware::RequestValidation,

    schema_path: 'schema.yaml' use Committee::Middleware::ResponseValidation, schema_path: 'schema.yaml' get "/apps" do content_type :json # page should be Integer page = params["page"].to_i [page, (page*10)].to_json end This API returns string array but when returns integer array (we should call `map(&:to_s)` )
  57. require "sinatra" require "committee" use Committee::Middleware::RequestValidation, schema_path: 'schema.yaml' use Committee::Middleware::ResponseValidation,

    schema_path: 'schema.yaml' get "/apps" do content_type :json # page should be Integer page = params["page"].to_i [page, (page*10)].to_json end We get error response from committee And we can change to write log and return the response Response validation using committee % curl -X GET "http://localhost:4567/apps?page=1" {"id":"invalid_response","message":"1 class is Integer but it's not valid string in #/paths/~1apps/get/responses/200/content/application~1json/schema/items"}
  58. Test Assertions describe "GET /apps" do it "conforms to schema"

    do get '/apps?page=1' assert_schema_conform end end % bundle exec ruby committee_test.rb Run options: --seed 62877 # Running: E Finished in 0.023367s, 42.7954 runs/s, 0.0000 assertions/s. 1) Error: Committee::Middleware::Stub::GET /apps#test_0001_conforms to schema: Committee::InvalidResponse: don't exist status code definition in #/paths/~1apps/get/responses • committee provides response format checker for test • When there’re difference, test will fail
  59. committee secures the reliability • Committee supports request/response validation •

    We can check if it’s a valid request and response by unit test or integration test • So we can trust that the interface is correctly implemented along with the schema
  60. How to implement 
 request/response validator using OpenAPI 3

  61. Inside committee • The committee initially supported only JSON Hyper-Schema

    and OpenAPI 2 validation • So I added new validation feature using OpenAPI 3 to committee
  62. Tight coupling with JSON Hyper- Schema • committee converted OpenAPI

    2 to JSON Hyper-Schema so committee validated one schema only • Validator was strongly coupled to JSON Hyper-Schema
  63. • OpenAPI 3 structure is different from JSON Hyper-Schema and

    • OpenAPI 3 have many new features (like security) • I decided to refactoring and implement a new validator for OpenAPI 3 Implement new validator
  64. Refactoring in committee • The committee does three steps

  65. Refactoring in committee • The committee does three steps •

    Rack layer processing SBDLNJEEMFXBSF
  66. Refactoring in committee • The committee does three steps •

    Rack layer processing • Find the schema from the request SBDLNJEEMFXBSF +40/)ZQFS4DIFNB 4DIFNB URL + HTTP method
  67. SBDLNJEEMFXBSF Refactoring in committee • The committee does three steps

    • Rack layer processing • Find the schema from the request • Validation using schema +40/)ZQFS4DIFNB 7BMJEBUPS validate 4DIFNB QBSBNFUFS
  68. SBDLNJEEMFXBSF Refactoring in committee • The committee does three steps

    • Rack layer processing • Find the schema from the request • Validation using schema +40/)ZQFS4DIFNB 7BMJEBUPS validate 4DIFNB QBSBNFUFS Depends on 
 JSON Hyper-Schema
  69. Refactoring schema finder SBDLNJEEMFXBSF +40/)ZQFS4DIFNB 4DIFNB URL + HTTP method

    • Rack middleware pass URL and HTTP method to definition and get schema so don’t need to know detail of definition
  70. Abstracted schema definition • So I create abstracted schema class

    and made rack middleware depend on it URL + HTTP method %FpOJUJPO SBDLNJEEMFXBSF
  71. Abstracted schema definition +40/)ZQFS4DIFNB URL + HTTP method %FpOJUJPO SBDLNJEEMFXBSF

    • So I create abstracted schema class and made rack middleware depend on it • The middleware don’t care it’s JSON Hyper-Schema or OpenAPI 3
  72. 0QFO"1* Abstracted schema definition URL + HTTP method %FpOJUJPO SBDLNJEEMFXBSF

    • So I create abstracted schema class and made rack middleware depend on it • The middleware don’t care it’s JSON Hyper-Schema or OpenAPI 3
  73. Refactoring validator • Rack middleware validate using schema object from

    definition and request/response data from rack • But middleware don’t need to know more about schema SBDLNJEEMFXBSF 7BMJEBUPS validate 4DIFNB QBSBNFUFS +40/)ZQFS4DIFNB %FpOJUJPO
  74. SBDLNJEEMFXBSF Abstracted validator • I create abstracted validator which include

    schema definition • The middleware gets it from definition URL + HTTP method %FpOJUJPO "CTUSBDUWBMJEBUPS 4DIFNB +40/)ZQFS4DIFNB +40/)ZQFS4DIFNB
  75. Abstracted validator • The middleware passes parameter to the validator

    for validation %FpOJUJPO "CTUSBDU7BMJEBUPS 4DIFNB +40/)ZQFS4DIFNB +40/)ZQFS4DIFNB QBSBNFUFS validate SBDLNJEEMFXBSF
  76. Abstracted validator • The middleware passes parameter to the validator

    for validation • So rack middleware don’t need to know the definition is OpenAPI 3 or JSON Hyper-Schema %FpOJUJPO "CTUSBDU7BMJEBUPS 4DIFNB 0QFO"1* 0QFO"1* QBSBNFUFS validate SBDLNJEEMFXBSF
  77. Abstracted validator • The middleware passes parameter to the validator

    for validation • So rack middleware don’t need to know the definition is OpenAPI 3 or JSON Hyper-Schema %FpOJUJPO "CTUSBDU7BMJEBUPS 4DIFNB 0QFO"1* 0QFO"1* QBSBNFUFS validate SBDLNJEEMFXBSF
  78. openapi_parser gem • OpenAPI 3 parser is separated gem
 https://github.com/ota42y/openapi_parser

    • So we can implement another gem for OpenAPI 3 validation
 (e.g. more Ruby on ̋̋̋̋̋ friendly validator) • OpenAPI 3 parser is separated gem
 https://github.com/ota42y/openapi_parser • So we can implement another gem for OpenAPI 3 validation
 (e.g. more Ruby on ̋̋̋̋̋ friendly validator)
  79. Inside openapi_parser gem • OpenAPI 3 parser has 3 feature

    • Mapping definition data to Ruby object • Finding schema from path and HTTP method • Validating parameter using schema
  80. Mapping OpenAPI definition to object • OpenAPI 3 definition have

    many object openapi: 3.0.0 info: title: Sample API version: 0.1.0 paths: "/apps": get: parameters: - name: page in: query required: true schema: type: integer responses: '200': description: example content: 'application/json': schema: type: array items: type: string
  81. Mapping OpenAPI definition to object • OpenAPI 3 definition have

    many object • Definition is YAML/JSON file so 
 ruby loads it as Hash objects • openapi: 3.0.0 info: title: Sample API version: 0.1.0 paths: "/apps": get: parameters: - name: page in: query required: true schema: type: integer responses: '200': description: example content: 'application/json': schema: type: array items: type: string
  82. Mapping OpenAPI definition to object • openapi_parser map definition data

    to Ruby object using DSL • I implemented few methods to these classes module OpenAPIParser::Schemas class Parameter < Base openapi_attr_values :name, :in, :description, :req openapi_attr_value :allow_empty_value, schema_key: openapi_attr_value :allow_reserved, schema_key: :a def validate_params(params, options)
  83. Inside openapi_parser gem • OpenAPI 3 parser has 3 feature

    • Mapping definition data to Ruby object • Finding schema from path and HTTP method • Validating parameter using schema
  84. %FpOJUJPO "CTUSBDU7BMJEBUPS 4DIFNB 0QFO"1* 0QFO"1* QBSBNFUFS validate SBDLNJEEMFXBSF URL +

    HTTP method
  85. openapi: 3.0.0 info: title: Sample API version: 0.1.0 paths: "/apps":

    get: parameters: - name: page in: query required: true schema: type: integer responses: '200': description: example content: 'application/json': schema: type: array items: type: string • Schema is defined separately for each HTTP method in Path Item Object Find schema from URL Path Item Object Path string
  86. openapi: 3.0.0 info: title: Sample API version: 0.1.0 paths: "/apps":

    get: parameters: - name: page in: query required: true schema: type: integer responses: '200': description: example content: 'application/json': schema: type: array items: type: string • Schema is defined separately for each HTTP method in Path Item Object Find schema from URL Path Item Object
  87. openapi: 3.0.0 info: title: Sample API version: 0.1.0 paths: "/apps":

    get: parameters: - name: page in: query required: true schema: type: integer responses: '200': description: example content: 'application/json': schema: type: array items: type: string • Schema is defined separately for each HTTP method in Path Item Object • So we should find Path Item Object from requested URL Find schema from URL Path Item Object Path string
  88. OpenAPI 3 support path parameter paths: "/pets/mine": … Requested path

    Definition path /pets/mine -> "/pets/mine" 

  89. OpenAPI 3 support path parameter paths: "/pets/mine": … "/pets/{petId}": …

    Requested path Definition path /pets/mine -> "/pets/mine" /pets/1 -> "/pets/{petId}" /pets/2 -> "/pets/{petId}" 

  90. OpenAPI 3 support path parameter paths: "/pets/mine": … "/pets/{petId}": …

    "/pets/0": … Requested path Definition path /pets/mine -> "/pets/mine" /pets/1 -> "/pets/{petId}" /pets/2 -> "/pets/{petId}" /pets/0 -> "/pets/0" 
 /pets/1/food -> "/pets/{petId}/food" /pets/0/food -> "/pets/0/food/" • If there are both with and without parameters, the one without parameters takes precedence
  91. OpenAPI 3 support path parameter paths: "/pets/mine": … "/pets/{petId}": …

    "/pets/0": … Requested path Definition path /pets/mine -> "/pets/mine" /pets/1 -> "/pets/{petId}" /pets/2 -> "/pets/{petId}" /pets/0 -> "/pets/0" 
 /pets/1/food -> "/pets/{petId}/food" /pets/0/food -> "/pets/0/food/" • If there are both with and without parameters, the one without parameters takes precedence • So we should find Path Item Object according this rule
  92. Support many API • If we are using JSON Hyper-Schema

    in committee, do the same thing but it was a full search • But we have many API ( One server had up to 500 APIs) • So we want to more efficient data structure
  93. • Patricia tree is space-optimized trie tree • All nodes

    have string value and child node have parent’s prefix Patricia tree Patricia trie.svg: Claudio Rocchini CC-BY 2.5
  94. Patricia tree for path string

  95. • Divide defined path by `/` and create node Patricia

    tree for path string users /users/meals/me me meals
  96. • Divide defined path by `/` and create node •

    Build tree Patricia tree for path string users /users/meals/me me meals
  97. • Divide defined path by `/` and create node •

    Build tree Patricia tree for path string users meals me
  98. • Divide defined path by `/` and create node •

    Build tree • Add new path’s nodes Patricia tree for path string users /users/meals/{id} {id} meals users meals me
  99. • Divide defined path by `/` and create node •

    Build tree • Add new path’s nodes • If there is same node, skip it and use shared node Patricia tree for path string users meals me users {id} meals
  100. • Divide defined path by `/` and create node •

    Build tree • Add new path’s nodes • If there is same node, skip it and use shared node Patricia tree for path string users meals me users {id} meals
  101. • Divide defined path by `/` and create node •

    Build tree • Add new path’s nodes • If there is same node, skip it and use shared node Patricia tree for path string users users meals me {id} meals
  102. • Divide defined path by `/` and create node •

    Build tree • Add new path’s nodes • If there is same node, skip it and use shared node Patricia tree for path string users users meals me {id} meals
  103. • Divide defined path by `/` and create node •

    Build tree • Add new path’s nodes • If there is same node, skip it and use shared node Patricia tree for path string users {id} meals users meals me
  104. • Divide defined path by `/` and create node •

    Build tree • Add new path’s nodes • If there is same node, skip it and use shared node • Add all paths Patricia tree for path string users {id} meals users meals me
  105. Find defined path from patricia tree lunch {id} users meals

    me steps lunch public root
  106. lunch • Divide requested URL by `/` too • Find

    node from root {id} users meals me steps lunch /users/meals/42/lunch public root Find defined path from patricia tree
  107. lunch • Divide requested URL by `/` too • Find

    node from root Find defined path from patricia tree {id} users meals me steps lunch /users/meals/42/lunch public root
  108. lunch • Divide requested URL by `/` too • Find

    node from root Find defined path from patricia tree {id} users meals me steps lunch /users/meals/42/lunch public root
  109. lunch • Divide requested URL by `/` too • Find

    node from root Find defined path from patricia tree {id} users meals me steps lunch /users/meals/42/lunch public root
  110. lunch • Divide requested URL by `/` too • Find

    node from root • If there isn’t matched node, 
 use parameter node (OpenAPI 3 definition) Find defined path from patricia tree {id} users meals me steps lunch /users/meals/42/lunch public root
  111. lunch • Divide requested URL by `/` too • Find

    node from root • If there isn’t matched node, 
 use parameter node (OpenAPI 3 definition) Find defined path from patricia tree {id} users meals me steps lunch /users/meals/42/lunch public root
  112. lunch • Divide requested URL by `/` too • Find

    node from root • If there isn’t matched node, 
 use parameter node (OpenAPI 3 definition) Find defined path from patricia tree {id} users meals me steps lunch /users/meals/42/lunch public root
  113. lunch • Divide requested URL by `/` too • Find

    node from root • If there isn’t matched node, 
 use parameter node (OpenAPI 3 definition) Find defined path from patricia tree {id} users meals me steps lunch /users/meals/42/lunch public root
  114. lunch • Divide requested URL by `/` too • Find

    node from root • If there isn’t matched node, 
 use parameter node (OpenAPI 3 definition) Find defined path from patricia tree {id} users meals me steps lunch /users/meals/{id}/lunch public root
  115. lunch • Divide requested URL by `/` too • Find

    node from root • If there isn’t matched node, 
 use parameter node (OpenAPI 3 definition) • Get Path Item Object from matched Find defined path from patricia tree {id} users meals me steps lunch /users/meals/{id}/lunch public root
  116. %FpOJUJPO "CTUSBDU7BMJEBUPS 4DIFNB 0QFO"1* 0QFO"1* QBSBNFUFS validate SBDLNJEEMFXBSF URL +

    HTTP method
  117. • When we find a schema, we can validate the

    parameter • OpenAPI 3 schema is subset of the JSON Schema Specification Wright Draft 00 Parameter validation
  118. schema: type: object nullable: false properties: nickname: type: string string,

    boolean, integer • There are few types of schema in JSON Schema Parameter validation schema: type: string format: email schema: type: array items: type: object required: - id properties: id: type: integer object array
  119. • JSON Schema has `string`, `boolean`, `integer` type • These

    can be mapped same Ruby class so it’s easy to check Standard validation schema: type: string format: email
  120. • JSON Schema has `object` type Object validation schema: type:

    object nullable: false properties: nickname: type: string
  121. • JSON Schema has `object` type • This type has

    `properties` which has property name and schema Object validation schema: type: object nullable: false properties: nickname: type: string
  122. • JSON Schema has `object` type • This type has

    `properties` which has property name and schema • This type can be mapped to Hash in ruby 
 and property name is represented as hash key Object validation schema: type: object nullable: false properties: nickname: type: string
  123. • JSON Schema has `object` type • This type has

    `properties` which has property name and schema • This type can be mapped to Hash in ruby 
 and property name is represented as hash key Object validation schema: type: object nullable: false properties: nickname: type: string schema.properties.each do |name, child_schema| child_schema.validate(parameter[name]) end
  124. • The `array` type in JSON Schema which can be

    mapped Array Array validation schema: type: array items: type: object required: ...
  125. • The `array` type in JSON Schema which can be

    mapped Array • The `array` type has items schema definition Array validation schema: type: array items: type: object required: ...
  126. • The `array` type in JSON Schema which can be

    mapped Array • The `array` type has items schema definition • Check all item in array is according to schema Array validation schema: type: array items: type: object required: ... array_parameter.all? do |item| items_schema.validate(item) end
  127. openapi_parser include these methods • These feature is implemented in

    openapi_parser
 and it’s separated from committee
  128. openapi_parser include these methods • These feature is implemented in

    openapi_parser
 and it’s separated from committee # load OpenAPI 3 definition root = OpenAPIParser.parse(YAML.load_file('open_api_3/schema.yml'))
  129. openapi_parser include these methods • These feature is implemented in

    openapi_parser
 and it’s separated from committee # load OpenAPI 3 definition root = OpenAPIParser.parse(YAML.load_file('open_api_3/schema.yml')) # get schema from HTTP method (POST) and path (/validate) op = root.request_operation(:post, '/validate')
  130. openapi_parser include these methods • These feature is implemented in

    openapi_parser
 and it’s separated from committee # load OpenAPI 3 definition root = OpenAPIParser.parse(YAML.load_file('open_api_3/schema.yml')) # get schema from HTTP method (POST) and path (/validate) op = root.request_operation(:post, '/validate') # validate request body ret = op.validate_request_body('application/json', params)
  131. openapi_parser include these methods • These feature is implemented in

    openapi_parser
 and it’s separated from committee • So if you want to create OpenAPI 3 tool, this gem help for you # load OpenAPI 3 definition root = OpenAPIParser.parse(YAML.load_file('open_api_3/schema.yml')) # get schema from HTTP method (POST) and path (/validate) op = root.request_operation(:post, '/validate') # validate request body ret = op.validate_request_body('application/json', params)
  132. Other OpenAPI 3 tools

  133. Client library generation

  134. OpenAPI Generator • Generate API client and Server stub from

    OpenAPI definition • Many language and framework supported (OpenAPI Generator is a folk of Swagger Codegen)
  135. Generate Ruby gem • This generator generates API client library

    as gem • You can try this command (using docker) % docker run --rm -w /local -v ${PWD}:/local openapitools/openapi-generator-cli \ generate \ -i schema.yaml \ -g ruby \ -o output_dir
  136. Generated gem • One method is created for one HTTP

    method definition api_instance = OpenapiClient::DefaultApi.new page = 56 result = api_instance.apps_get(page)
  137. Generated gem • One method is created for one HTTP

    method definition api_instance = OpenapiClient::DefaultApi.new page = 56 result = api_instance.apps_get(page) GET /apps
  138. Generated gem • One method is created for one HTTP

    method • If you want to divide by namespace, use tags in OpenAPI 3
 (OpenAPI 3 allow add tag per HTTP method) api_instance = OpenapiClient::DefaultApi.new page = 56 result = api_instance.apps_get(page) users_api = OpenapiClient::UsersApi.new limit = 10 users_api.blogs_get(limit)
  139. Document Included • OpenAPI 3 supports markdown description for many

    objects • OpenAPI Generator convert request / response parameter as method argument and return value and outputs these as YARD style comments with description # get app names by array # @param page specific page setting # @param [Hash] opts the optional parameters # @return [Array<String>] def apps_get(page, opts = {})
  140. Generete type definition…? • I think we can generate type

    definition (.rbi) class DefaultApi def apps_get: (page: Integer) -> Array<String> end
  141. Generete type definition…? • I think we can generate type

    definition (.rbi) • And we can generate server side code like Hanami with .rbi class DefaultApi def apps_get: (page: Integer) -> Array<String> end module Web module Controllers module Home class Index include Web::Action def call(params) end end
  142. Interactive Document • Swagger UI provide 
 interactive document 


    (but no Ruby… ) • It provides human-readable
 documents and the ability to
 try out a request
  143. Interactive Editor • Swagger Editor provide interactive editor

  144. If there is time, I’m going to demo

  145. Convert OpenAPI 2 to OpenAPI 3 • There is OpenAPI

    2 to OpenAPI 3 converter • https://mermade.org.uk/openapi-converter
  146. JSON Hyper-Schema to OpenAPI 3 • I created JSON Hyper-Schema

    to OpenAPI 3 • https://github.com/ota42y/json_hyperscheme_to_openapi3
  147. JSON Hyper-Schema to OpenAPI 3 • I created JSON Hyper-Schema

    to OpenAPI 3 • https://github.com/ota42y/json_hyperscheme_to_openapi3 • But we need additional data to convert
  148. JSON Hyper-Schema to OpenAPI 3 • I created JSON Hyper-Schema

    to OpenAPI 3 • https://github.com/ota42y/json_hyperscheme_to_openapi3 • But we need additional data to convert • We need path parameter as additional data "/pets/{id}": get: parameters: - name: id in: path schema: type: integer
  149. Other tools • Mock server • Definition converter (e.g. OpenAPI

    3 to protocol buffers) • Please see OpenAPI.Tools site
 (https://openapi.tools/)
  150. Summary

  151. Summary • We can use OpenAPI 3 to define API

    schema • OpenAPI 3 has various tools • Request/Respones validation • Client library generation • Interactive document • If you want to create new OpenAPI tool, it’s not so difficult
  152. Summary • We can use OpenAPI 3 to define API

    schema • OpenAPI 3 has various tools • Request/Respones validation • Client library generation • Interactive document • If you want to create new OpenAPI tool, it’s not so difficult
  153. Summary • We can use OpenAPI 3 to define API

    schema • OpenAPI 3 has various tools • Request/Respones validation • Client library generation • Interactive document • If you want to create new OpenAPI tool, it’s not so difficult
  154. Apache License Version 2.0, January 2004 http://www.apache.org/licenses/ TERMS AND CONDITIONS

    FOR USE, REPRODUCTION, AND DISTRIBUTION 1. Definitions. "License" shall mean the terms and conditions for use, reproduction, and distribution as defined by Sections 1 through 9 of this document. "Licensor" shall mean the copyright owner or entity authorized by the copyright owner that is granting the License. "Legal Entity" shall mean the union of the acting entity and all other entities that control, are controlled by, or are under common control with that entity. For the purposes of this definition, "control" means (i) the power, direct or indirect, to cause the direction or management of such entity, whether by contract or otherwise, or (ii) ownership of fifty percent (50%) or more of the outstanding shares, or (iii) beneficial ownership of such entity. "You" (or "Your") shall mean an individual or Legal Entity exercising permissions granted by this License. "Source" form shall mean the preferred form for making modifications, including but not limited to software source code, documentation source, and configuration files. "Object" form shall mean any form resulting from mechanical transformation or translation of a Source form, including but not limited to compiled object code, generated documentation, and conversions to other media types. "Work" shall mean the work of authorship, whether in Source or Object form, made available under the License, as indicated by a copyright notice that is included in or attached to the work (an example is provided in the Appendix below). "Derivative Works" shall mean any work, whether in Source or Object form, that is based on (or derived from) the Work and for which the editorial revisions, annotations, elaborations, or other modifications represent, as a whole, an original work of authorship. For the purposes of this License, Derivative Works shall not include works that remain separable from, or merely link (or bind by name) to the interfaces of, the Work and Derivative Works thereof. "Contribution" shall mean any work of authorship, including the original version of the Work and any modifications or additions to that Work or Derivative Works thereof, that is intentionally submitted to Licensor for inclusion in the Work by the copyright owner or by an individual or Legal Entity authorized to submit on behalf of the copyright owner. For the purposes of this definition, "submitted" means any form of electronic, verbal, or written communication sent to the Licensor or its representatives, including but not limited to communication on electronic mailing lists, source code control systems, and issue tracking systems that are managed by, or on behalf of, the Licensor for the purpose of discussing and improving the Work, but excluding communication that is conspicuously marked or otherwise designated in writing by the copyright owner as "Not a Contribution." "Contributor" shall mean Licensor and any individual or Legal Entity on behalf of whom a Contribution has been received by Licensor and subsequently incorporated within the Work. 2. Grant of Copyright License. Subject to the terms and conditions of this License, each Contributor hereby grants to You a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare Derivative Works of, publicly display, publicly perform, sublicense, and distribute the Work and such Derivative Works in Source or Object form. 3. Grant of Patent License. Subject to the terms and conditions of this License, each Contributor hereby grants to You a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable (except as stated in this section) patent license to make, have made, use, offer to sell, sell, import, and otherwise transfer the Work, where such license applies only to those patent claims licensable by such Contributor that are necessarily infringed by their Contribution(s) alone or by combination of their Contribution(s) with the Work to which such Contribution(s) was submitted. If You institute patent litigation against any entity (including a cross-claim or counterclaim in a lawsuit) alleging that the Work or a Contribution incorporated within the Work constitutes direct or contributory patent infringement, then any patent licenses granted to You under this License for that Work shall terminate as of the date such litigation is filed. 4. Redistribution. You may reproduce and distribute copies of the Work or Derivative Works thereof in any medium, with or without modifications, and in Source or Object form, provided that You meet the following conditions: (a) You must give any other recipients of the Work or Derivative Works a copy of this License; and (b) You must cause any modified files to carry prominent notices stating that You changed the files; and (c) You must retain, in the Source form of any Derivative Works that You distribute, all copyright, patent, trademark, and attribution notices from the Source form of the Work, excluding those notices that do not pertain to any part of the Derivative Works; and (d) If the Work includes a "NOTICE" text file as part of its distribution, then any Derivative Works that You distribute must include a readable copy of the attribution notices contained within such NOTICE file, excluding those notices that do not pertain to any part of the Derivative Works, in at least one of the following places: within a NOTICE text file distributed as part of the Derivative Works; within the Source form or documentation, if provided along with the Derivative Works; or, within a display generated by the Derivative Works, if and wherever such third-party notices normally appear. The contents of the NOTICE file are for informational purposes only and do not modify the License. You may add Your own attribution notices within Derivative Works that You distribute, alongside or as an addendum to the NOTICE text from the Work, provided that such additional attribution notices cannot be construed as modifying the License. You may add Your own copyright statement to Your modifications and may provide additional or different license terms and conditions for use, reproduction, or distribution of Your modifications, or for any such Derivative Works as a whole, provided Your use, reproduction, and distribution of the Work otherwise complies with the conditions stated in this License. 5. Submission of Contributions. Unless You explicitly state otherwise, any Contribution intentionally submitted for inclusion in the Work by You to the Licensor shall be under the terms and conditions of this License, without any additional terms or conditions. Notwithstanding the above, nothing herein shall supersede or modify the terms of any separate license agreement you may have executed with Licensor regarding such Contributions. 6. Trademarks. This License does not grant permission to use the trade names, trademarks, service marks, or product names of the Licensor, except as required for reasonable and customary use in describing the origin of the Work and reproducing the content of the NOTICE file. 7. Disclaimer of Warranty. Unless required by applicable law or agreed to in writing, Licensor provides the Work (and each Contributor provides its Contributions) on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied, including, without limitation, any warranties or conditions of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A PARTICULAR PURPOSE. You are solely responsible for determining the appropriateness of using or redistributing the Work and assume any risks associated with Your exercise of permissions under this License. 8. Limitation of Liability. In no event and under no legal theory, whether in tort (including negligence), contract, or otherwise, unless required by applicable law (such as deliberate and grossly negligent acts) or agreed to in writing, shall any Contributor be liable to You for damages, including any direct, indirect, special, incidental, or consequential damages of any character arising as a result of this License or out of the use or inability to use the Work (including but not limited to damages for loss of goodwill, work stoppage, computer failure or malfunction, or any and all other commercial damages or losses), even if such Contributor has been advised of the possibility of such damages. 9. Accepting Warranty or Additional Liability. While redistributing the Work or Derivative Works thereof, You may choose to offer, and charge a fee for, acceptance of support, warranty, indemnity, or other liability obligations and/or rights consistent with this License. However, in accepting such obligations, You may act only on Your own behalf and on Your sole responsibility, not on behalf of any other Contributor, and only if You agree to indemnify, defend, and hold each Contributor harmless for any liability incurred by, or claims asserted against, such Contributor by reason of your accepting any such warranty or additional liability. END OF TERMS AND CONDITIONS APPENDIX: How to apply the Apache License to your work. To apply the Apache License to your work, attach the following boilerplate notice, with the fields enclosed by brackets "{}" replaced with your own identifying information. (Don't include the brackets!) The text should be enclosed in the appropriate comment syntax for the file format. We also recommend that a file or class name and description of purpose be included on the same "printed page" as the copyright notice for easier identification within third-party archives. Copyright The Linux Foundation Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0 Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.
  155. Additional slides
 (I added after the end 
 There is

    answers for Q&A)
  156. Do you use committee in production? • Yes • We

    use request validator and coerce all value in production • But we don’t use response validator in production, we use staging only • Because if we implement request/response by correct in staging, we don’t need check in production • committee has parameter coercer so we use request validation in production
  157. Committee is slow? • It is a benchmark result •

    Small benchmark have 1 query parameter • Big benchmark have 2600 objects • Check enable/disable committee and request 1000 times • I don’t check response validation benchmark because we don’t use it in production • Benchmark script is here
 https://gist.github.com/ota42y/3ed68a2cb0dc7c98122bdfd1a696ab72
  158. Small result • 1000 times request • So committee need

    0.2 milliseconds in every request VTFS TZTUFN UPUBM SFBM /PU6TF     6TF    
  159. Big result • Validate 2600 objects by 6 milliseconds
 (

    In many cases, it is about 100 at most, so I think that there is no problem) VTFS TZTUFN UPUBM SFBM /PU6TF     6TF