如何在容器和外部连接之间建立连接？

我正在构建 docker（从这里）更改网络以能够将容器连接到容器。但是由于某种原因，我无法从计算机连接到容器，并且容器无法连接：docker-compose：

version: '3.4'

services:
  webapi:
    image: ${DOCKER_REGISTRY-}webapi
    build:
      context: .
      dockerfile: WebApi/Dockerfile
    depends_on:
      - db  
ports:
  - "8000:80"     
expose:  
  - 80
  
  db:
    image: microsoft/mssql-server-linux:2017-latest
    container_name: webapisqldb
    environment:
        ACCEPT_EULA: Y
        SA_PASSWORD: "Bassword@123"
    ports:  
      - '1433:1433'  
    expose:  
      - 1433
    volumes:  
      - sql-data:/var/opt/mssql3  

volumes:
      sql-data:
networks:
  outside:
    external: true

码头工人：

FROM mcr.microsoft.com/dotnet/core/aspnet:3.0.0-preview7-buster-slim AS base
WORKDIR /app
EXPOSE 80

FROM mcr.microsoft.com/dotnet/core/sdk:3.0.100-preview7-buster AS build
WORKDIR /src
COPY ["WebApi/WebApi.csproj", "WebApi/"]
RUN dotnet restore "WebApi/WebApi.csproj"
COPY . .
WORKDIR "/src/WebApi"
RUN dotnet build "WebApi.csproj" -c Release -o /app

FROM build AS publish
RUN dotnet publish "WebApi.csproj" -c Release -o /app

FROM base AS final
WORKDIR /app
COPY --from=publish /app .
ENTRYPOINT ["dotnet", "WebApi.dll"]

有没有人有将 docker 与数据库连接并使一切正常的示例？