openapi-first

Create OpenAPI yaml files and generate contract C# files

Generate contract code from json contract

• Install Microsoft dotnet-openapi tool https://docs.microsoft.com/en-us/aspnet/core/web-api/microsoft.dotnet-openapi
• dotnet tool install -g Microsoft.dotnet-openapi
• dotnet openapi add file --updateProject .\Ref.csproj ..\OpenAPIs\contract-first-swagger.json

Enrich the contract based on yaml format

• https://editor.swagger.io - view/edit contract or convert to yaml

• http://stevetalkscode.co.uk/openapireference-commands

 <OpenApiReferenceInclude="OpenAPIs\swagger.yaml"CodeGenerator="NSwagCSharp"Link="OpenAPIs\swagger.yaml"Options="/DateType:NodaTime.LocalDate /GenerateOptionalPropertiesAsNullable:true /GenerateNullableReferenceTypes:true"Namespace="WebApiFromTemplate"AdditionalNamespaceUsages="NodaTime">
<AdditionalNamespaceUsages>NodaTime</AdditionalNamespaceUsages>
<SourceUri>https://localhost:5051/swagger/v1/swagger.yaml</SourceUri>
</OpenApiReference>

OpenAPI data types

• json schema https://datatracker.ietf.org/doc/html/draft-bhutton-json-schema-validation-00#section-7.3
• extra types https://github.com/OAI/OpenAPI-Specification/blob/main/versions/3.1.0.md#data-types

#tools

• Visual Studio code OpenAPI editor https://marketplace.visualstudio.com/items?itemName=42Crunch.vscode-openapi
• Visual Studio Code REST client https://marketplace.visualstudio.com/items?itemName=humao.rest-client
• editor.swagger.io