OpenAPI definitions of sample API integrated with a Lambda function

{
 "swagger": "2.0",
 "info": {
 "version": "2017-04-20T04:08:08Z",
 "title": "LambdaCalc"
 },
 "host": "uojnr9hd57.execute-api.us-east-1.amazonaws.com",
 "basePath": "/test",
 "schemes": [
 "https"
 ],
 "paths": {
 "/calc": {
 "get": {
 "consumes": [
 "application/json"
 ],
 "produces": [
 "application/json"
 ],
 "parameters": [
 {
 "name": "operand2",
 "in": "query",
 "required": true,
 "type": "string"
 },
 {
 "name": "operator",
 "in": "query",
 "required": true,
 "type": "string"
 },
 {
 "name": "operand1",
 "in": "query",
 "required": true,
 "type": "string"
 }
 ],
 "responses": {
 "200": {
 "description": "200 response",
 "schema": {
 "$ref": "#/definitions/Result"
 },
 "headers": {
 "operand_1": {
 "type": "string"
 },
 "operand_2": {
 "type": "string"
 },
 "operator": {
 "type": "string"
 }
 }
 }
 },
 "x-amazon-apigateway-request-validator": "Validate query string parameters and headers",
 "x-amazon-apigateway-integration": {
 "credentials": "arn:aws:iam::123456789012:role/apigAwsProxyRole",
 "responses": {
 "default": {
 "statusCode": "200",
 "responseParameters": {
 "method.response.header.operator": "integration.response.body.op",
 "method.response.header.operand_2": "integration.response.body.b",
 "method.response.header.operand_1": "integration.response.body.a"
 },
 "responseTemplates": {
 "application/json": "#set($res = $input.path('$'))\n{\n \"result\": \"$res.a, $res.b, $res.op => $res.c\",\n \"a\" : \"$res.a\",\n \"b\" : \"$res.b\",\n \"op\" : \"$res.op\",\n \"c\" : \"$res.c\"\n}"
 }
 }
 },
 "uri": "arn:aws:apigateway:us-west-2:lambda:path/2015-03-31/functions/arn:aws:lambda:us-west-2:123456789012:function:Calc/invocations",
 "passthroughBehavior": "when_no_match",
 "httpMethod": "POST",
 "requestTemplates": {
 "application/json": "{\n \"a\": \"$input.params('operand1')\",\n \"b\": \"$input.params('operand2')\", \n \"op\": \"$input.params('operator')\" \n}"
 },
 "type": "aws"
 }
 },
 "post": {
 "consumes": [
 "application/json"
 ],
 "produces": [
 "application/json"
 ],
 "parameters": [
 {
 "in": "body",
 "name": "Input",
 "required": true,
 "schema": {
 "$ref": "#/definitions/Input"
 }
 }
 ],
 "responses": {
 "200": {
 "description": "200 response",
 "schema": {
 "$ref": "#/definitions/Result"
 }
 }
 },
 "x-amazon-apigateway-request-validator": "Validate body",
 "x-amazon-apigateway-integration": {
 "credentials": "arn:aws:iam::123456789012:role/apigAwsProxyRole",
 "responses": {
 "default": {
 "statusCode": "200",
 "responseTemplates": {
 "application/json": "#set($inputRoot = $input.path('$'))\n{\n \"a\" : $inputRoot.a,\n \"b\" : $inputRoot.b,\n \"op\" : $inputRoot.op,\n \"c\" : $inputRoot.c\n}"
 }
 }
 },
 "uri": "arn:aws:apigateway:us-west-2:lambda:path/2015-03-31/functions/arn:aws:lambda:us-west-2:123456789012:function:Calc/invocations",
 "passthroughBehavior": "when_no_templates",
 "httpMethod": "POST",
 "type": "aws"
 }
 }
 },
 "/calc/{operand1}/{operand2}/{operator}": {
 "get": {
 "consumes": [
 "application/json"
 ],
 "produces": [
 "application/json"
 ],
 "parameters": [
 {
 "name": "operand2",
 "in": "path",
 "required": true,
 "type": "string"
 },
 {
 "name": "operator",
 "in": "path",
 "required": true,
 "type": "string"
 },
 {
 "name": "operand1",
 "in": "path",
 "required": true,
 "type": "string"
 }
 ],
 "responses": {
 "200": {
 "description": "200 response",
 "schema": {
 "$ref": "#/definitions/Result"
 }
 }
 },
 "x-amazon-apigateway-integration": {
 "credentials": "arn:aws:iam::123456789012:role/apigAwsProxyRole",
 "responses": {
 "default": {
 "statusCode": "200",
 "responseTemplates": {
 "application/json": "#set($inputRoot = $input.path('$'))\n{\n \"input\" : {\n \"a\" : $inputRoot.a,\n \"b\" : $inputRoot.b,\n \"op\" : \"$inputRoot.op\"\n },\n \"output\" : {\n \"c\" : $inputRoot.c\n }\n}"
 }
 }
 },
 "uri": "arn:aws:apigateway:us-west-2:lambda:path/2015-03-31/functions/arn:aws:lambda:us-west-2:123456789012:function:Calc/invocations",
 "passthroughBehavior": "when_no_templates",
 "httpMethod": "POST",
 "requestTemplates": {
 "application/json": "{\n \"a\": \"$input.params('operand1')\",\n \"b\": \"$input.params('operand2')\",\n \"op\": #if($input.params('operator')=='%2F')\"/\"#{else}\"$input.params('operator')\"#end\n \n}"
 },
 "contentHandling": "CONVERT_TO_TEXT",
 "type": "aws"
 }
 }
 }
 },
 "definitions": {
 "Input": {
 "type": "object",
 "required": [
 "a",
 "b",
 "op"
 ],
 "properties": {
 "a": {
 "type": "number"
 },
 "b": {
 "type": "number"
 },
 "op": {
 "type": "string",
 "description": "binary op of ['+', 'add', '-', 'sub', '*', 'mul', '%2F', 'div']"
 }
 },
 "title": "Input"
 },
 "Output": {
 "type": "object",
 "properties": {
 "c": {
 "type": "number"
 }
 },
 "title": "Output"
 },
 "Result": {
 "type": "object",
 "properties": {
 "input": {
 "$ref": "#/definitions/Input"
 },
 "output": {
 "$ref": "#/definitions/Output"
 }
 },
 "title": "Result"
 }
 },
 "x-amazon-apigateway-request-validators": {
 "Validate body": {
 "validateRequestParameters": false,
 "validateRequestBody": true
 },
 "Validate query string parameters and headers": {
 "validateRequestParameters": true,
 "validateRequestBody": false
 }
 }
}