Hands-On RESTful Web Services with ASP.NET Core 3

Multi-stage builds on the catalog service

Let's apply the concept of a multi-stage build to the previously defined Docker image. Multi-stage builds are a new feature that requires Docker 17.05 or higher. Multi-stage builds are useful for anyone who has struggled to optimize Dockerfiles while keeping them easy to read and maintain.

Let's explore how it is possible to apply the multi-stage build process by taking a look at the catalog service Dockerfile:

FROM microsoft/dotnetCOPY . /appWORKDIR /appRUN dotnet restoreRUN dotnet buildRUN chmod +x ./entrypoint.shCMD /bin/bash ./entrypoint.sh

The previously defined file can be changed in the following way:

FROM mcr.microsoft.com/dotnet/core/aspnet:3.1 AS baseWORKDIR /appFROM mcr.microsoft.com/