# Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved.
# SPDX-License-Identifier: MIT-0
#
# Permission is hereby granted, free of charge, to any person obtaining a copy of this
# software and associated documentation files (the "Software"), to deal in the Software
# without restriction, including without limitation the rights to use, copy, modify,
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# permit persons to whom the Software is furnished to do so.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
# INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
# PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
# HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
# OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
# SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

openapi: "3.0.1"
info:
  title: "URL Shortener API"
  version: "1.0.0"

x-amazon-apigateway-request-validators:
  all:
    validateRequestBody: true
    validateRequestParameters: true
  params:
    validateRequestBody: false
    validateRequestParameters: true
  body:
    validateRequestBody: true
    validateRequestParameters: false

paths:
  /{linkId}:
    ## URL redirector
    get:
      summary: Get a url by ID and redirect
      x-amazon-apigateway-request-validator: params
      parameters:
        - in: path
          name: linkId
          schema:
            type: string
          required: true
          description: Short link ID for full URL
      responses:
        "301":
          description: "301 redirect"
          headers:
            Location:
              type: "string"
            Cache-Control:
              type: "string"
      
      ## API Gateway Integration
      x-amazon-apigateway-integration:
        credentials:
          Fn::GetAtt: [ DDBReadRole, Arn ]
        uri: {"Fn::Sub":"arn:aws:apigateway:${AWS::Region}:dynamodb:action/GetItem"}
        httpMethod: "POST"
        requestTemplates:
          application/json: {"Fn::Sub": "{\"Key\": {\"id\": {\"S\": \"$input.params().path.linkId\"}}, \"TableName\": \"${LinkTable}\"}"}
        passthroughBehavior: "when_no_templates"
        responses:
          "200":
            statusCode: "301"
            responseParameters:
              method.response.header.Location: {"Fn::Sub": ["'master.${ampDomain}?error=url_not_found'", { "ampDomain": {"Fn::GetAtt":["AmplifyApp", "DefaultDomain"]} }]}
              method.response.header.Cache-Control: "'max-age=300'"
            responseTemplates:
              application/json: "#set($inputRoot = $input.path('$')) \
                #if($inputRoot.toString().contains(\"Item\")) \
                #set($context.responseOverride.header.Location = $inputRoot.Item.url.S) \
                #end"
        type: "aws"

  /app:
    ## Get all links for user
    get:
      summary: Fetch all links for authenticated user
      security:
      - UserAuthorizer: []
      parameters:
        - $ref: '#/components/parameters/authHeader'
      responses:
        "200":
          description: "200 response"
          headers:
            Access-Control-Allow-Origin:
              type: "string"
            Cache-Control:
              type: "string"
            

      ## API Gateway Integration
      x-amazon-apigateway-integration:
        credentials:
          Fn::GetAtt: [ DDBReadRole, Arn ]
        uri: {"Fn::Sub":"arn:aws:apigateway:${AWS::Region}:dynamodb:action/Query"}
        httpMethod: "POST"
        requestTemplates:
          application/json: { "Fn::Sub": "{\"TableName\": \"${LinkTable}\", \
            \"IndexName\":\"OwnerIndex\",\"KeyConditionExpression\": \"#n_owner = :v_owner\", \
            \"ExpressionAttributeValues\": \
            {\":v_owner\": {\"S\": \"$context.authorizer.claims.email\"}},\"ExpressionAttributeNames\": {\"#n_owner\": \"owner\"}}"}
        passthroughBehavior: "when_no_templates"
        responses:
          "200":
            statusCode: "200"
            responseParameters:
              method.response.header.Cache-Control: "'no-cache, no-store'"
              method.response.header.Access-Control-Allow-Origin: {"Fn::If": ["IsLocal", "'*'", {"Fn::Sub": ["'https://master.${ampDomain}'", { "ampDomain": {"Fn::GetAtt":["AmplifyApp", "DefaultDomain"]} }]}]}
            responseTemplates:
              application/json: "#set($inputRoot = $input.path('$'))[ \
                #foreach($elem in $inputRoot.Items) { \
                  \"id\":\"$elem.id.S\", \
                  \"url\": \"$elem.url.S\", \
                  \"timestamp\": \"$elem.timestamp.S\", \
                  \"owner\": \"$elem.owner.S\"} \
                #if($foreach.hasNext),#end \
                #end]"
        type: "AWS"

    ## Create a new link
    post:
      summary: Create new url
      security:
      - UserAuthorizer: []
      x-amazon-apigateway-request-validator: body
      parameters:
        - $ref: '#/components/parameters/authHeader'
      requestBody:
        description: Optional description in *Markdown*
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/PostBody'
      responses:
        "200":
          description: "200 response"
          headers:
            Access-Control-Allow-Origin:
              type: "string"
        "400":
          description: "400 response"
          headers:
            Access-Control-Allow-Origin:
              type: "string"

      ## API Gateway integration
      x-amazon-apigateway-integration:
        credentials:
          Fn::GetAtt: [ DDBCrudRole, Arn ]
        uri: { "Fn::Sub": "arn:aws:apigateway:${AWS::Region}:dynamodb:action/UpdateItem" }
        httpMethod: "POST"
        requestTemplates:
          application/json: { "Fn::Sub": "{\"TableName\": \"${LinkTable}\",\
            \"ConditionExpression\":\"attribute_not_exists(id)\", \
            \"Key\": {\"id\": {\"S\": $input.json('$.id')}}, \
            \"ExpressionAttributeNames\": {\"#u\": \"url\",\"#o\": \"owner\",\"#ts\": \"timestamp\"}, \
            \"ExpressionAttributeValues\":{\":u\": {\"S\": $input.json('$.url')},\":o\": {\"S\": \"$context.authorizer.claims.email\"},\":ts\": {\"S\": \"$context.requestTime\"}}, \
            \"UpdateExpression\": \"SET #u = :u, #o = :o, #ts = :ts\", \
            \"ReturnValues\": \"ALL_NEW\"}" }
        passthroughBehavior: "when_no_templates"
        responses:
          "200":
            statusCode: "200"
            responseParameters:
              method.response.header.Access-Control-Allow-Origin: {"Fn::If": ["IsLocal", "'*'", {"Fn::Sub": ["'https://master.${ampDomain}'", { "ampDomain": {"Fn::GetAtt":["AmplifyApp", "DefaultDomain"]} }]}]}
            responseTemplates:
              application/json: "#set($inputRoot = $input.path('$')) \
                {\"id\":\"$inputRoot.Attributes.id.S\", \
                \"url\":\"$inputRoot.Attributes.url.S\",
                \"timestamp\":\"$inputRoot.Attributes.timestamp.S\", \
                \"owner\":\"$inputRoot.Attributes.owner.S\"}"
          "400":
            statusCode: "400"
            responseParameters:
              method.response.header.Access-Control-Allow-Origin: {"Fn::If": ["IsLocal", "'*'", {"Fn::Sub": ["'https://master.${ampDomain}'", { "ampDomain": {"Fn::GetAtt":["AmplifyApp", "DefaultDomain"]} }]}]}
            responseTemplates:
              application/json: "#set($inputRoot = $input.path('$')) \
                #if($inputRoot.toString().contains(\"ConditionalCheckFailedException\")) \
                #set($context.responseOverride.status = 200)
                {\"error\": true,\"message\": \"URL link already exists\"} \
                #end"
        type: "aws"

    ## Options for get and post that do not have a linkId
    options:
      responses:
        "200":
          description: "200 response"
          headers:
            Access-Control-Allow-Origin:
              schema:
                type: "string"
            Access-Control-Allow-Methods:
              schema:
                type: "string"
            Access-Control-Allow-Headers:
              schema:
                type: "string"
      x-amazon-apigateway-integration:
        requestTemplates:
          application/json: "{\"statusCode\": 200}"
        passthroughBehavior: "when_no_match"
        responses:
          default:
            statusCode: "200"
            responseParameters:
              method.response.header.Access-Control-Allow-Methods: "'POST, GET, OPTIONS'"
              method.response.header.Access-Control-Allow-Headers: "'authorization, content-type'"
              method.response.header.Access-Control-Allow-Origin: {"Fn::If": ["IsLocal", "'*'", {"Fn::Sub": ["'https://master.${ampDomain}'", { "ampDomain": {"Fn::GetAtt":["AmplifyApp", "DefaultDomain"]} }]}]}
        type: "mock"

  /app/{linkId}:
    ## Delete link
    delete:
      summary: Delete url
      security:
      - UserAuthorizer: []
      x-amazon-apigateway-request-validator: params
      parameters:
        - $ref: '#/components/parameters/authHeader'
        - $ref: '#/components/parameters/linkIdHeader'
      responses:
        "200":
          description: "200 response"
          headers:
            Access-Control-Allow-Origin:
              type: "string"
        "400":
          description: "400 response"
      
      ## AOI gateway integration
      x-amazon-apigateway-integration:
        credentials:
          Fn::GetAtt: [ DDBCrudRole, Arn ]
        uri: { "Fn::Sub": "arn:aws:apigateway:${AWS::Region}:dynamodb:action/DeleteItem" }
        httpMethod: "POST"
        requestTemplates:
          application/json: { "Fn::Sub":  "{\"Key\": {\"id\": {\"S\": \"$input.params().path.linkId\"}}, \
            \"TableName\": \"${LinkTable}\", \
            \"ConditionExpression\": \"#owner = :owner\", \
            \"ExpressionAttributeValues\":{\":owner\": {\"S\": \"$context.authorizer.claims.email\"}}, \
            \"ExpressionAttributeNames\": {\"#owner\": \"owner\"}}" }
        passthroughBehavior: "when_no_templates"
        responses:
          "200":
            statusCode: "200"
            responseParameters:
              method.response.header.Access-Control-Allow-Origin: {"Fn::If": ["IsLocal", "'*'", {"Fn::Sub": ["'https://master.${ampDomain}'", { "ampDomain": {"Fn::GetAtt":["AmplifyApp", "DefaultDomain"]} }]}]}
          "400":
            statusCode: "400"
            responseTemplates:
              application/json: "{\"error\": {\"message\":\"Either you do not have permission to do this operation or a parameter is missing\"}}"
        type: "aws"
    ## Update links
    put:
      summary: Update specific URL
      security:
      - UserAuthorizer: []
      x-amazon-apigateway-request-validator: body
      requestBody:
        description: Optional description in *Markdown*
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/PutBody'
      parameters:
        - $ref: '#/components/parameters/authHeader'
        - $ref: '#/components/parameters/linkIdHeader'
      responses:
        "200":
          description: "301 response"
          headers:
            Access-Control-Allow-Origin:
              type: "string"
        "400":
          description: "400 response"
          headers:
            Access-Control-Allow-Origin:
              type: "string"
      
      ## API gateway integration
      x-amazon-apigateway-integration:
        credentials:
          Fn::GetAtt: [ DDBCrudRole, Arn ]
        uri: { "Fn::Sub": "arn:aws:apigateway:${AWS::Region}:dynamodb:action/UpdateItem" }
        httpMethod: "POST"
        requestTemplates:
          application/json: { "Fn::Sub": "{\"TableName\": \"${LinkTable}\",\
            \"Key\": {\"id\": {\"S\": $input.json('$.id')}}, \
            \"ExpressionAttributeNames\": {\"#u\": \"url\", \"#owner\": \"owner\", \"#id\":\"id\"}, \
            \"ExpressionAttributeValues\":{\":u\": {\"S\": $input.json('$.url')}, \":owner\": {\"S\": \"$context.authorizer.claims.email\"}, \":linkId\":{\"S\":\"$input.params().path.linkId\"}}, \
            \"UpdateExpression\": \"SET #u = :u\", \
            \"ReturnValues\": \"ALL_NEW\", \
            \"ConditionExpression\": \"#owner = :owner AND #id = :linkId\"}" }
        passthroughBehavior: "when_no_templates"
        responses:
          "200":
            statusCode: "200"
            responseParameters:
              method.response.header.Access-Control-Allow-Origin: {"Fn::If": ["IsLocal", "'*'", {"Fn::Sub": ["'https://master.${ampDomain}'", { "ampDomain": {"Fn::GetAtt":["AmplifyApp", "DefaultDomain"]} }]}]}
            responseTemplates:
              application/json: "#set($inputRoot = $input.path('$')) \
                {\"id\":\"$inputRoot.Attributes.id.S\", \
                \"url\":\"$inputRoot.Attributes.url.S\",
                \"timestamp\":\"$inputRoot.Attributes.timestamp.S\", \
                \"owner\":\"$inputRoot.Attributes.owner.S\"}"
          "400":
            statusCode: "400"
            responseParameters:
              method.response.header.Access-Control-Allow-Origin: {"Fn::If": ["IsLocal", "'*'", {"Fn::Sub": ["'https://master.${ampDomain}'", { "ampDomain": {"Fn::GetAtt":["AmplifyApp", "DefaultDomain"]} }]}]}
            application/json: "{\"error\": {\"message\":\"Either you do not have permission to do this operation or a parameter is missing\"}}"
        type: "aws"
    options:
      responses:
        "200":
          description: "200 response"
          headers:
            Access-Control-Allow-Origin:
              schema:
                type: "string"
            Access-Control-Allow-Methods:
              schema:
                type: "string"
            Access-Control-Allow-Headers:
              schema:
                type: "string"
      x-amazon-apigateway-integration:
        requestTemplates:
          application/json: "{\"statusCode\" : 200}"
        passthroughBehavior: "when_no_match"
        responses:
          default:
            statusCode: "200"
            responseParameters:
              method.response.header.Access-Control-Allow-Methods: "'PUT, DELETE, OPTIONS'"
              method.response.header.Access-Control-Allow-Headers: "'authorization, content-type'"
              method.response.header.Access-Control-Allow-Origin: {"Fn::If": ["IsLocal", "'*'", {"Fn::Sub": ["'https://master.${ampDomain}'", { "ampDomain": {"Fn::GetAtt":["AmplifyApp", "DefaultDomain"]} }]}]}
        type: "mock"

## Validation models
components:
  schemas:
    PostBody:
      type: object
      properties:
        id:
          type: string
        url:
          type: string
          pattern: ^https?://[-a-zA-Z0-9@:%._\+~#=]{2,256}\.[a-z]{2,6}\b([-a-zA-Z0-9@:%_\+.~#?&//=]*)
      required:
        - id
        - url
    PutBody:
      type: object
      properties:
        id:
          type: string
        url:
          type: string
          pattern: /((([A-Za-z]{3,9}:(?:\/\/)?)(?:[-;:&=\+\$,\w]+@)?[A-Za-z0-9.-]+|(?:www.|[-;:&=\+\$,\w]+@)[A-Za-z0-9.-]+)((?:\/[\+~%\/.\w-_]*)?\??(?:[-\+=&;%@.\w_]*)#?(?:[\w]*))?)/
        timestamp:
          type: string
        owner:
          type: string
      required:
        - id
        - url
        - timestamp
        - owner
  parameters:
    authHeader:
      in: header
      name: Authorization
      required: true
      description: Contains authorization token
      schema:
        type: string
    linkIdHeader:
      in: path
      name: linkId
      required: true
      description: Short link ID for full URL
      schema:
        type: string

## Authorizer definition
securityDefinitions:
  UserAuthorizer:
    type: "apiKey"
    name: "Authorization"
    in: "header"
    x-amazon-apigateway-authtype: "cognito_user_pools"
    x-amazon-apigateway-authorizer:
      providerARNs:
      - Fn::GetAtt: [ UserPool, Arn ]
      type: "cognito_user_pools"