Imagem externa no Multistage build

Além de copiar imagens que fazem parte das imagens intermediárias é possível copiar arquivos de outras imagens inclusive repositórios remotos.

Criação de uma imagem para armazenar o pacote binário:

$ pwd
/tmp/pacote
$ touch pacote.bin
$ vim pacote.bin
$ cat pacote.bin
Binário
$ touch Dockerfile
$ vim Dockerfile
$ cat Dockerfile
FROM alpine:3.20.2
WORKDIR /pkg
COPY . .
$ docker image build -t marcelodpbarbieri/pacote-bin -f Dockerfile .
[+] Building 3.5s (9/9) FINISHED                                                                          docker:default
 => [internal] load build definition from Dockerfile                                                                0.0s
 => => transferring dockerfile: 78B                                                                                 0.0s
 => [internal] load metadata for docker.io/library/alpine:3.20.2                                                    2.7s
 => [auth] library/alpine:pull token for registry-1.docker.io                                                       0.0s
 => [internal] load .dockerignore                                                                                   0.0s
 => => transferring context: 2B                                                                                     0.0s
 => [1/3] FROM docker.io/library/alpine:3.20.2@sha256:0a4eaa0eecf5f8c050e5bba433f58c052be7587ee8af3e8b3910ef9ab5fb  0.5s
 => => resolve docker.io/library/alpine:3.20.2@sha256:0a4eaa0eecf5f8c050e5bba433f58c052be7587ee8af3e8b3910ef9ab5fb  0.0s
 => => sha256:c6a83fedfae6ed8a4f5f7cbb6a7b6f1c1ec3d86fea8cb9e5ba2e5e6673fde9f6 3.62MB / 3.62MB                      0.4s
 => => sha256:0a4eaa0eecf5f8c050e5bba433f58c052be7587ee8af3e8b3910ef9ab5fbe9f5 1.85kB / 1.85kB                      0.0s
 => => sha256:eddacbc7e24bf8799a4ed3cdcfa50d4b88a323695ad80f317b6629883b2c2a78 528B / 528B                          0.0s
 => => sha256:324bc02ae1231fd9255658c128086395d3fa0aedd5a41ab6b034fd649d1a9260 1.47kB / 1.47kB                      0.0s
 => => extracting sha256:c6a83fedfae6ed8a4f5f7cbb6a7b6f1c1ec3d86fea8cb9e5ba2e5e6673fde9f6                           0.1s
 => [internal] load build context                                                                                   0.0s
 => => transferring context: 126B                                                                                   0.0s
 => [2/3] WORKDIR /pkg                                                                                              0.0s
 => [3/3] COPY . .                                                                                                  0.0s
 => exporting to image                                                                                              0.1s
 => => exporting layers                                                                                             0.0s
 => => writing image sha256:04018fdd126926818c26277636375115b46c41bccb00668af58a0fcf4b8654b8                        0.0s
 => => naming to docker.io/marcelodpbarbieri/pacote-bin                                                             0.0s
$ docker image ls
REPOSITORY                     TAG       IMAGE ID       CREATED          SIZE
marcelodpbarbieri/pacote-bin   latest    04018fdd1269   24 seconds ago   7.8MB
$ docker image push marcelodpbarbieri/pacote-bin
Using default tag: latest
The push refers to repository [docker.io/marcelodpbarbieri/pacote-bin]
dbbf66204e71: Pushed
289d56dfbc63: Pushed
78561cef0761: Mounted from marcelodpbarbieri/conversao-temperatura
latest: digest: sha256:d8eda8c30cd5bfaa0dcce6b903496c1415c849a9c351f6016ef845591ca44651 size: 940
$ docker container run -it marcelodpbarbieri/pacote-bin /bin/sh
/pkg # ls
Dockerfile  pacote.bin

https://hub.docker.com/repository/docker/marcelodpbarbieri/pacote-bin/generalhub.docker.com

Construção da imagem final com referência ao pacote.bin da imagem remota.

Dockerfile:

# IMAGEM INTERMEDIARIA
# imagem base nomeada como build
FROM golang:1.18.1 AS build
WORKDIR /build
COPY . .
# compilacao da aplicacao
RUN CGO_ENABLED=0 GOOS=linux go build -a -installsuffix cgo -o main .

# IMAGEM FINAL
# imagem base nomeada como app
FROM alpine:3.20.2 AS app
WORKDIR /app
# copia arquivo de imagem remota
COPY --from=marcelodpbarbieri/pacote-bin:latest /pkg/pacote.bin .
# copia do binario da imagem intermediaria (build) para a imagem final
COPY --from=build /build/main .
CMD ["./main"]

Destaque para:

# copia arquivo de imagem remota
COPY --from=marcelodpbarbieri/pacote-bin:latest /pkg/pacote.bin .

Construção da imagem final:

$ pwd
/tmp/go
$ docker image build -t marcelodpbarbieri/app-multistage:multistage -f Dockerfile .
[+] Building 37.5s (18/18) FINISHED                                                                       docker:default
 => [internal] load build definition from Dockerfile                                                                0.0s
 => => transferring dockerfile: 545B                                                                                0.0s
 => [internal] load metadata for docker.io/marcelodpbarbieri/pacote-bin:latest                                      0.0s
 => [internal] load metadata for docker.io/library/golang:1.18.1                                                    2.8s
 => [internal] load metadata for docker.io/library/alpine:3.20.2                                                    1.4s
 => [auth] library/alpine:pull token for registry-1.docker.io                                                       0.0s
 => [auth] library/golang:pull token for registry-1.docker.io                                                       0.0s
 => [internal] load .dockerignore                                                                                   0.0s
 => => transferring context: 2B                                                                                     0.0s
 => [build 1/4] FROM docker.io/library/golang:1.18.1@sha256:12d3995156cb0dcdbb9d3edb5827e4e8e1bf5bf92436bfd12d696  24.8s
 => => resolve docker.io/library/golang:1.18.1@sha256:12d3995156cb0dcdbb9d3edb5827e4e8e1bf5bf92436bfd12d696ec99700  0.0s
 => => sha256:5b75b529da0f2196ee8561a90e5b99aceee56e125c6ef09a3da4e32cf3cc6c20 1.80kB / 1.80kB                      0.0s
 => => sha256:65375c930b214d93a4c09a1db748e6979ef53ad585ec864dbe837108d48d8d14 7.05kB / 7.05kB                      0.0s
 => => sha256:c357e2c68cb3bf1e98dcb3eb6ceb16837253db71535921d6993c594588bffe04 10.87MB / 10.87MB                    2.0s
 => => sha256:12d3995156cb0dcdbb9d3edb5827e4e8e1bf5bf92436bfd12d696ec997001a9a 2.35kB / 2.35kB                      0.0s
 => => sha256:967757d5652770cfa81b6cc7577d65e06d336173da116d1fb5b2d349d5d44127 5.16MB / 5.16MB                      1.0s
 => => sha256:6aefca2dc61dcbcd268b8a9861e552f9cdb69e57242faec64ac120d2355a9c1a 54.94MB / 54.94MB                    2.5s
 => => sha256:c766e27afb21eddf9ab3e4349700ebe697c32a4c6ada6af4f08282277a291a28 54.58MB / 54.58MB                    4.1s
 => => sha256:d6a8ea6bd5f867dbdf5bad1c42bc569afacf062a0241c1a8b45718fc8ae26fba 85.84MB / 85.84MB                    7.8s
 => => extracting sha256:6aefca2dc61dcbcd268b8a9861e552f9cdb69e57242faec64ac120d2355a9c1a                           5.2s
 => => sha256:13a9b904f7423b8b1f02a99df065ceb2de067207d626915b84776bb0c918ed0f 141.70MB / 141.70MB                  9.8s
 => => sha256:3447e3508f49d81eb14b0cf466950f15126161f20f2d70b8d429017d2b08a74f 156B / 156B                          4.5s
 => => extracting sha256:967757d5652770cfa81b6cc7577d65e06d336173da116d1fb5b2d349d5d44127                           0.7s
 => => extracting sha256:c357e2c68cb3bf1e98dcb3eb6ceb16837253db71535921d6993c594588bffe04                           0.5s
 => => extracting sha256:c766e27afb21eddf9ab3e4349700ebe697c32a4c6ada6af4f08282277a291a28                           3.6s
 => => extracting sha256:d6a8ea6bd5f867dbdf5bad1c42bc569afacf062a0241c1a8b45718fc8ae26fba                           3.2s
 => => extracting sha256:13a9b904f7423b8b1f02a99df065ceb2de067207d626915b84776bb0c918ed0f                           8.0s
 => => extracting sha256:3447e3508f49d81eb14b0cf466950f15126161f20f2d70b8d429017d2b08a74f                           0.0s
 => [internal] load build context                                                                                   0.1s
 => => transferring context: 928B                                                                                   0.0s
 => FROM docker.io/marcelodpbarbieri/pacote-bin:latest                                                              0.1s
 => CACHED [app 1/4] FROM docker.io/library/alpine:3.20.2@sha256:0a4eaa0eecf5f8c050e5bba433f58c052be7587ee8af3e8b3  0.0s
 => [app 2/4] WORKDIR /app                                                                                          0.1s
 => [app 3/4] COPY --from=marcelodpbarbieri/pacote-bin:latest /pkg/pacote.bin .                                     0.1s
 => [build 2/4] WORKDIR /build                                                                                      0.7s
 => [build 3/4] COPY . .                                                                                            0.1s
 => [build 4/4] RUN CGO_ENABLED=0 GOOS=linux go build -a -installsuffix cgo -o main .                               8.8s
 => [app 4/4] COPY --from=build /build/main .                                                                       0.1s
 => exporting to image                                                                                              0.1s
 => => exporting layers                                                                                             0.1s
 => => writing image sha256:8b69e2fd86c7a5513045571b1ceead461c3ddca8c7f003a5af286e175547f429                        0.0s
 => => naming to docker.io/marcelodpbarbieri/app-multistage:multistage                                              0.0s

Destaque para:

=> [app 3/4] COPY --from=marcelodpbarbieri/pacote-bin:latest /pkg/pacote.bin .

Teste da aplicação:

$ docker container run -d -p 8080:8080 marcelodpbarbieri/app-multistage:multistage
22faa5f4dd259e87e1ecc13b2de6dc0cb3e868858fc0554cdedfd5e7ec8f05b6

Acessar o container:

$ docker container ls
CONTAINER ID   IMAGE                                         COMMAND    CREATED              STATUS              PORTS                                       NAMES
22faa5f4dd25   marcelodpbarbieri/app-multistage:multistage   "./main"   About a minute ago   Up About a minute   0.0.0.0:8080->8080/tcp, :::8080->8080/tcp   awesome_poincare
$ docker exec -it 22faa5f4dd25 /bin/bash
OCI runtime exec failed: exec failed: unable to start container process: exec: "/bin/bash": stat /bin/bash: no such file or directory: unknown
$ docker exec -it 22faa5f4dd25 /bin/sh
/app # ls
main        pacote.bin