13.2.4. 引用镜像流中的镜像
可以使用以下引用类型在镜像流中引用镜像：
ImageStreamTag用于引用或检索给定镜像流和标签的镜像。它的名称使用以下惯例：<image_stream_name>:<tag>
ImageStreamImage用于引用或检索给定镜像流和镜像名称的镜像。它的名称使用以下惯例：<image_stream_name>@<id>
<id>是针对特定镜像的不可变标识符，也称摘要。DockerImage用于引用或检索给定外部 registry 的镜像。它使用标准 Docker 拉取规格 作为名称，例如：openshift/ruby-20-centos7:2.0
注意如果未指定标签，则会假定使用 latest标签。
此外，您还可引用第三方 registry：
registry.redhat.io/rhel7:latest
或者带有摘要的镜像：
centos/ruby-22-centos7@sha256:3a335d7d8a452970c5b4054ad7118ff134b3a6b50a2bb6d0c07c746e8986b28e
当查看镜像流定义示例时，如 CentOS 镜像流示例，您可能会注意到它们包含 ImageStreamTag 的定义以及 DockerImage 的引用，但不与 ImageStreamImage 相关。
这是因为当您将镜像导入或标记到镜像流时，OpenShift Container Platform 中会自动创建 ImageStreamImage 对象。您不必在用于创建镜像流的任何镜像流定义中显式定义 ImageStreamImage 对象。
您可以使用镜像流名称和 ID 检索 ImageStreamImage 定义，来查看镜像的对象定义：
$ oc get -o yaml --export isimage <image_stream_name>@<id>
您可以运行以下命令来找到给定镜像流的有效 <id> 值：
$ oc describe is <image_stream_name>
例如，在 ruby 镜像流中，要求 ImageStreamImage 的名称和 ID 为 ruby@3a335d7 ：
通过 ImageStreamImage检索镜像对象的定义
$ oc get -o yaml --export isimage ruby@3a335d7
apiVersion: v1
image:
dockerImageLayers:
- name: sha256:a3ed95caeb02ffe68cdd9fd84406680ae93d633cb16422d00e8a7c22955b46d4
size: 0
- name: sha256:ee1dd2cb6df21971f4af6de0f1d7782b81fb63156801cfde2bb47b4247c23c29
size: 196634330
- name: sha256:a3ed95caeb02ffe68cdd9fd84406680ae93d633cb16422d00e8a7c22955b46d4
size: 0
- name: sha256:a3ed95caeb02ffe68cdd9fd84406680ae93d633cb16422d00e8a7c22955b46d4
size: 0
- name: sha256:ca062656bff07f18bff46be00f40cfbb069687ec124ac0aa038fd676cfaea092
size: 177723024
- name: sha256:63d529c59c92843c395befd065de516ee9ed4995549f8218eac6ff088bfa6b6e
size: 55679776
dockerImageMetadata:
Architecture: amd64
Author: SoftwareCollections.org <sclorg@redhat.com>
Config:
Cmd:
- /bin/sh
- -c
- $STI_SCRIPTS_PATH/usage
Entrypoint:
- container-entrypoint
Env:
- PATH=/opt/app-root/src/bin:/opt/app-root/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin
- STI_SCRIPTS_URL=image:///usr/libexec/s2i
- STI_SCRIPTS_PATH=/usr/libexec/s2i
- HOME=/opt/app-root/src
- BASH_ENV=/opt/app-root/etc/scl_enable
- ENV=/opt/app-root/etc/scl_enable
- PROMPT_COMMAND=. /opt/app-root/etc/scl_enable
- RUBY_VERSION=2.2
ExposedPorts:
8080/tcp: {}
Image: d9c3abc5456a9461954ff0de8ae25e0e016aad35700594714d42b687564b1f51
Labels:
build-date: 2015-12-23
io.k8s.description: Platform for building and running Ruby 2.2 applications
io.k8s.display-name: Ruby 2.2
io.openshift.builder-base-version: 8d95148
io.openshift.builder-version: 8847438ba06307f86ac877465eadc835201241df
io.openshift.s2i.scripts-url: image:///usr/libexec/s2i
io.openshift.tags: builder,ruby,ruby22
io.s2i.scripts-url: image:///usr/libexec/s2i
license: GPLv2
name: CentOS Base Image
vendor: CentOS
User: "1001"
WorkingDir: /opt/app-root/src
ContainerConfig: {}
Created: 2016-01-26T21:07:27Z
DockerVersion: 1.8.2-el7
Id: 57b08d979c86f4500dc8cad639c9518744c8dd39447c055a3517dc9c18d6fccd
Parent: d9c3abc5456a9461954ff0de8ae25e0e016aad35700594714d42b687564b1f51
Size: 430037130
apiVersion: "1.0"
kind: DockerImage
dockerImageMetadataVersion: "1.0"
dockerImageReference: centos/ruby-22-centos7@sha256:3a335d7d8a452970c5b4054ad7118ff134b3a6b50a2bb6d0c07c746e8986b28e
metadata:
creationTimestamp: 2016-01-29T13:17:45Z
name: sha256:3a335d7d8a452970c5b4054ad7118ff134b3a6b50a2bb6d0c07c746e8986b28e
resourceVersion: "352"
uid: af2e7a0c-c68a-11e5-8a99-525400f25e34
kind: ImageStreamImage
metadata:
creationTimestamp: null
name: ruby@3a335d7
namespace: openshift
selflink: /oapi/v1/namespaces/openshift/imagestreamimages/ruby@3a335d7
