📅 最后修改于: 2020-10-31 13:52:44 🧑 作者: Mango
OpenShift包含两种类型的中位数，以通过GUI或CLI创建和部署应用程序。在本章中，我们将使用CLI创建一个新的应用程序。我们将使用OC客户端与OpenShift环境进行通信。
在OpenShift中，有三种创建新应用程序的方法。
当我们尝试从源代码创建应用程序时，OpenShift会在存储库中查找应该存在的Docker文件，该文件定义了应用程序的构建流程。我们将使用oc new-app创建一个应用程序。
使用存储库时要记住的第一件事是，它应指向存储库中的原点，OpenShift将在该源上提取代码并进行构建。
如果该存储库克隆在安装了OC客户端的Docker计算机上，并且用户位于同一目录内，则可以使用以下命令创建该存储库。
$ oc new-app .
以下是尝试从远程仓库为特定分支构建的示例。
$ oc new-app https://github.com/openshift/Testing-deployment.git#test1
在这里，test1是我们尝试在OpenShift中创建新应用程序的分支。
在存储库中指定Docker文件时，我们需要定义构建策略，如下所示。
$ oc new-app OpenShift/OpenShift-test~https://github.com/openshift/Testingdeployment.git
在使用映像构建应用程序时，映像存在于本地Docker服务器，内部托管的Docker存储库中或Docker集线器中。用户唯一需要确定的是，他有权从集线器中拉取图像而没有任何问题。
OpenShift能够确定所使用的源，无论是Docker映像还是源流。但是，如果用户希望，他可以明确定义它是映像流还是Docker映像。
$ oc new-app - - docker-image tomcat
使用图像流-
$ oc new-app tomcat:v1
模板可用于创建新应用程序。它可以是已经存在的模板，也可以创建一个新模板。
后面的yaml文件基本上是可用于部署的模板。
apiVersion: v1
kind: Template
metadata:
name:
annotations:
description:
iconClass: "icon-redis"
tags:
objects:
- apiVersion: v1
kind: Pod
metadata:
name: 为了在OpenShift中创建一个新的应用程序，我们必须编写一个新的应用程序代码并使用OpenShift OC构建命令对其进行构建。如上所述，我们有多种创建新映像的方法。在这里，我们将使用模板来构建应用程序。使用oc new-app命令运行时，此模板将构建一个新应用程序。
以下模板将创建-两个前端应用程序和一个数据库。随之，它将创建两个新服务，这些应用程序将被部署到OpenShift集群中。在构建和部署应用程序时，最初，我们需要在OpenShift中创建一个名称空间，然后在该名称空间下部署应用程序。
创建一个新的名称空间
$ oc new-project openshift-test --display-name = "OpenShift 3 Sample" --
description = "This is an example project to demonstrate OpenShift v3"
{
"kind": "Template",
"apiVersion": "v1",
"metadata": {
"name": "openshift-helloworld-sample",
"creationTimestamp": null,
"annotations": {
"description": "This example shows how to create a simple openshift
application in openshift origin v3",
"iconClass": "icon-openshift",
"tags": "instant-app,openshift,mysql"
}
}
},
模板中的秘密定义
"objects": [
{
"kind": "Secret",
"apiVersion": "v1",
"metadata": {"name": "dbsecret"},
"stringData" : {
"mysql-user" : "${MYSQL_USER}",
"mysql-password" : "${MYSQL_PASSWORD}"
}
},
模板中的服务定义
{
"kind": "Service",
"apiVersion": "v1",
"metadata": {
"name": "frontend",
"creationTimestamp": null
},
"spec": {
"ports": [
{
"name": "web",
"protocol": "TCP",
"port": 5432,
"targetPort": 8080,
"nodePort": 0
}
],
"selector": {"name": "frontend"},
"type": "ClusterIP",
"sessionAffinity": "None"
},
"status": {
"loadBalancer": {}
}
},
模板中的路线定义
{
"kind": "Route",
"apiVersion": "v1",
"metadata": {
"name": "route-edge",
"creationTimestamp": null,
"annotations": {
"template.openshift.io/expose-uri": "http://{.spec.host}{.spec.path}"
}
},
"spec": {
"host": "www.example.com",
"to": {
"kind": "Service",
"name": "frontend"
},
"tls": {
"termination": "edge"
}
},
"status": {}
},
{
"kind": "ImageStream",
"apiVersion": "v1",
"metadata": {
"name": "origin-openshift-sample",
"creationTimestamp": null
},
"spec": {},
"status": {
"dockerImageRepository": ""
}
},
{
"kind": "ImageStream",
"apiVersion": "v1",
"metadata": {
"name": "openshift-22-ubuntu7",
"creationTimestamp": null
},
"spec": {
"dockerImageRepository": "ubuntu/openshift-22-ubuntu7"
},
"status": {
"dockerImageRepository": ""
}
},
在模板中构建配置定义
{
"kind": "BuildConfig",
"apiVersion": "v1",
"metadata": {
"name": "openshift-sample-build",
"creationTimestamp": null,
"labels": {name": "openshift-sample-build"}
},
"spec": {
"triggers": [
{ "type": "GitHub",
"github": {
"secret": "secret101" }
},
{
"type": "Generic",
"generic": {
"secret": "secret101",
"allowEnv": true }
},
{
"type": "ImageChange",
"imageChange": {}
},
{ "type": "ConfigChange”}
],
"source": {
"type": "Git",
"git": {
"uri": https://github.com/openshift/openshift-hello-world.git }
},
"strategy": {
"type": "Docker",
"dockerStrategy": {
"from": {
"kind": "ImageStreamTag",
"name": "openshift-22-ubuntu7:latest”
},
"env": [
{
"name": "EXAMPLE",
"value": "sample-app"
}
]
}
},
"output": {
"to": {
"kind": "ImageStreamTag",
"name": "origin-openshift-sample:latest"
}
},
"postCommit": {
"args": ["bundle", "exec", "rake", "test"]
},
"status": {
"lastVersion": 0
}
}
},
模板中的部署配置
"status": {
"lastVersion": 0
}
{
"kind": "DeploymentConfig",
"apiVersion": "v1",
"metadata": {
"name": "frontend",
"creationTimestamp": null
}
},
"spec": {
"strategy": {
"type": "Rolling",
"rollingParams": {
"updatePeriodSeconds": 1,
"intervalSeconds": 1,
"timeoutSeconds": 120,
"pre": {
"failurePolicy": "Abort",
"execNewPod": {
"command": [
"/bin/true"
],
"env": [
{
"name": "CUSTOM_VAR1",
"value": "custom_value1"
}
]
}
}
}
}
}
"triggers": [
{
"type": "ImageChange",
"imageChangeParams": {
"automatic": true,
"containerNames": [
"openshift-helloworld"
],
"from": {
"kind": "ImageStreamTag",
"name": "origin-openshift-sample:latest"
}
}
},
{
"type": "ConfigChange"
}
],
"replicas": 2,
"selector": {
"name": "frontend"
},
"template": {
"metadata": {
"creationTimestamp": null,
"labels": {
"name": "frontend"
}
},
"spec": {
"containers": [
{
"name": "openshift-helloworld",
"image": "origin-openshift-sample",
"ports": [
{
"containerPort": 8080,
"protocol": "TCP”
}
],
"env": [
{
"name": "MYSQL_USER",
"valueFrom": {
"secretKeyRef" : {
"name" : "dbsecret",
"key" : "mysql-user"
}
}
},
{
"name": "MYSQL_PASSWORD",
"valueFrom": {
"secretKeyRef" : {
"name" : "dbsecret",
"key" : "mysql-password"
}
}
},
{
"name": "MYSQL_DATABASE",
"value": "${MYSQL_DATABASE}"
}
],
"resources": {},
"terminationMessagePath": "/dev/termination-log",
"imagePullPolicy": "IfNotPresent",
"securityContext": {
"capabilities": {},
"privileged": false
}
}
],
"restartPolicy": "Always",
"dnsPolicy": "ClusterFirst"
},
"status": {}
},
模板中的服务定义
{
"kind": "Service",
"apiVersion": "v1",
"metadata": {
"name": "database",
"creationTimestamp": null
},
"spec": {
"ports": [
{
"name": "db",
"protocol": "TCP",
"port": 5434,
"targetPort": 3306,
"nodePort": 0
}
],
"selector": {
"name": "database
},
"type": "ClusterIP",
"sessionAffinity": "None" },
"status": {
"loadBalancer": {}
}
},
模板中的部署配置定义
{
"kind": "DeploymentConfig",
"apiVersion": "v1",
"metadata": {
"name": "database",
"creationTimestamp": null
},
"spec": {
"strategy": {
"type": "Recreate",
"resources": {}
},
"triggers": [
{
"type": "ConfigChange"
}
],
"replicas": 1,
"selector": {"name": "database"},
"template": {
"metadata": {
"creationTimestamp": null,
"labels": {"name": "database"}
},
"template": {
"metadata": {
"creationTimestamp": null,
"labels": {
"name": "database"
}
},
"spec": {
"containers": [
{
"name": "openshift-helloworld-database",
"image": "ubuntu/mysql-57-ubuntu7:latest",
"ports": [
{
"containerPort": 3306,
"protocol": "TCP"
}
],
"env": [
{
"name": "MYSQL_USER",
"valueFrom": {
"secretKeyRef" : {
"name" : "dbsecret",
"key" : "mysql-user"
}
}
},
{
"name": "MYSQL_PASSWORD",
"valueFrom": {
"secretKeyRef" : {
"name" : "dbsecret",
"key" : "mysql-password"
}
}
},
{
"name": "MYSQL_DATABASE",
"value": "${MYSQL_DATABASE}"
}
],
"resources": {},
"volumeMounts": [
{
"name": "openshift-helloworld-data",
"mountPath": "/var/lib/mysql/data"
}
],
"terminationMessagePath": "/dev/termination-log",
"imagePullPolicy": "Always",
"securityContext": {
"capabilities": {},
"privileged": false
}
}
],
"volumes": [
{
"name": "openshift-helloworld-data",
"emptyDir": {"medium": ""}
}
],
"restartPolicy": "Always",
"dnsPolicy": "ClusterFirst”
}
}
},
"status": {}
},
"parameters": [
{
"name": "MYSQL_USER",
"description": "database username",
"generate": "expression",
"from": "user[A-Z0-9]{3}",
"required": true
},
{
"name": "MYSQL_PASSWORD",
"description": "database password",
"generate": "expression",
"from": "[a-zA-Z0-9]{8}",
"required": true
},
{
"name": "MYSQL_DATABASE",
"description": "database name",
"value": "root",
"required": true
}
],
"labels": {
"template": "application-template-dockerbuild"
}
}
上面的模板文件需要立即编译。我们需要首先将所有内容复制到一个文件中，并在完成后将其命名为yaml文件。
我们需要运行以下命令来创建应用程序。
$ oc new-app application-template-stibuild.json
--> Deploying template openshift-helloworld-sample for "application-template-stibuild.json"
openshift-helloworld-sample
---------
This example shows how to create a simple ruby application in openshift origin v3
* With parameters:
* MYSQL_USER = userPJJ # generated
* MYSQL_PASSWORD = cJHNK3se # generated
* MYSQL_DATABASE = root
--> Creating resources with label app = ruby-helloworld-sample ...
service "frontend" created
route "route-edge" created
imagestream "origin-ruby-sample" created
imagestream "ruby-22-centos7" created
buildconfig "ruby-sample-build" created
deploymentconfig "frontend" created
service "database" created
deploymentconfig "database" created
--> Success
Build scheduled, use 'oc logs -f bc/ruby-sample-build' to track its progress.
Run 'oc status' to view your app.
如果我们希望监视构建，可以使用-
$ oc get builds
NAME TYPE FROM STATUS STARTED DURATION
openshift-sample-build-1 Source Git@bd94cbb Running 7 seconds ago 7s
我们可以使用-在OpenShift上检查已部署的应用程序-
$ oc get pods
NAME READY STATUS RESTARTS AGE
database-1-le4wx 1/1 Running 0 1m
frontend-1-e572n 1/1 Running 0 27s
frontend-1-votq4 1/1 Running 0 31s
opeshift-sample-build-1-build 0/1 Completed 0 1m
我们可以使用以下命令检查是否根据服务定义创建了应用程序服务
$ oc get services
NAME CLUSTER-IP EXTERNAL-IP PORT(S) SELECTOR AGE
database 172.30.80.39 5434/TCP name=database 1m
frontend 172.30.17.4 5432/TCP name=frontend 1m