Chapter 5. Using build strategies
The following sections define the primary supported build strategies, and how to use them.
5.1. Docker build
OpenShift Container Platform uses Buildah to build a container image from a Dockerfile. For more information on building container images with Dockerfiles, see the Dockerfile reference documentation.
If you set Docker build arguments by using the buildArgs
array, see Understand how ARG and FROM interact in the Dockerfile reference documentation.
5.1.1. Replacing the Dockerfile FROM image
You can replace the FROM
instruction of the Dockerfile with the from
parameters of the BuildConfig
object. If the Dockerfile uses multi-stage builds, the image in the last FROM
instruction will be replaced.
Procedure
To replace the
FROM
instruction of the Dockerfile with thefrom
parameters of theBuildConfig
object, add the following settings to theBuildConfig
object:strategy: dockerStrategy: from: kind: "ImageStreamTag" name: "debian:latest"
5.1.2. Using Dockerfile path
By default, docker builds use a Dockerfile located at the root of the context specified in the BuildConfig.spec.source.contextDir
field.
The dockerfilePath
field allows the build to use a different path to locate your Dockerfile, relative to the BuildConfig.spec.source.contextDir
field. It can be a different file name than the default Dockerfile, such as MyDockerfile
, or a path to a Dockerfile in a subdirectory, such as dockerfiles/app1/Dockerfile
.
Procedure
Set the
dockerfilePath
field for the build to use a different path to locate your Dockerfile:strategy: dockerStrategy: dockerfilePath: dockerfiles/app1/Dockerfile
5.1.3. Using docker environment variables
To make environment variables available to the docker build process and resulting image, you can add environment variables to the dockerStrategy
definition of the build configuration.
The environment variables defined there are inserted as a single ENV
Dockerfile instruction right after the FROM
instruction, so that it can be referenced later on within the Dockerfile.
The variables are defined during build and stay in the output image, therefore they will be present in any container that runs that image as well.
For example, defining a custom HTTP proxy to be used during build and runtime:
dockerStrategy: ... env: - name: "HTTP_PROXY" value: "http://myproxy.net:5187/"
You can also manage environment variables defined in the build configuration with the oc set env
command.
5.1.4. Adding Docker build arguments
You can set Docker build arguments using the buildArgs
array. The build arguments are passed to Docker when a build is started.
See Understand how ARG and FROM interact in the Dockerfile reference documentation.
Procedure
To set Docker build arguments, add entries to the
buildArgs
array, which is located in thedockerStrategy
definition of theBuildConfig
object. For example:dockerStrategy: ... buildArgs: - name: "version" value: "latest"
NoteOnly the
name
andvalue
fields are supported. Any settings on thevalueFrom
field are ignored.
5.1.5. Squashing layers with docker builds
Docker builds normally create a layer representing each instruction in a Dockerfile. Setting the imageOptimizationPolicy
to SkipLayers
merges all instructions into a single layer on top of the base image.
Procedure
Set the
imageOptimizationPolicy
toSkipLayers
:strategy: dockerStrategy: imageOptimizationPolicy: SkipLayers
5.1.6. Using build volumes
You can mount build volumes to give running builds access to information that you do not want to persist in the output container image.
Build volumes provide sensitive information, such as repository credentials, that the build environment or configuration only needs at build time. Build volumes are different from build inputs, whose data can persist in the output container image.
The mount points of build volumes, from which the running build reads data, are functionally similar to pod volume mounts.
Prerequisites
- You have added an input secret, config map, or both to a BuildConfig object.
Procedure
In the
dockerStrategy
definition of theBuildConfig
object, add any build volumes to thevolumes
array. For example:spec: dockerStrategy: volumes: - name: secret-mvn 1 mounts: - destinationPath: /opt/app-root/src/.ssh 2 source: type: Secret 3 secret: secretName: my-secret 4 - name: settings-mvn 5 mounts: - destinationPath: /opt/app-root/src/.m2 6 source: type: ConfigMap 7 configMap: name: my-config 8 - name: my-csi-volume 9 mounts: - destinationPath: /opt/app-root/src/some_path 10 source: type: CSI 11 csi: driver: csi.sharedresource.openshift.io 12 readOnly: true 13 volumeAttributes: 14 attribute: value
- 1 5 9
- Required. A unique name.
- 2 6 10
- Required. The absolute path of the mount point. It must not contain
..
or:
and does not collide with the destination path generated by the builder. The/opt/app-root/src
is the default home directory for many Red Hat S2I-enabled images. - 3 7 11
- Required. The type of source,
ConfigMap
,Secret
, orCSI
. - 4 8
- Required. The name of the source.
- 12
- Required. The driver that provides the ephemeral CSI volume.
- 13
- Required. This value must be set to
true
. Provides a read-only volume. - 14
- Optional. The volume attributes of the ephemeral CSI volume. Consult the CSI driver’s documentation for supported attribute keys and values.
ImportantShared Resource CSI Driver is a Technology Preview feature only. Technology Preview features are not supported with Red Hat production service level agreements (SLAs) and might not be functionally complete. Red Hat does not recommend using them in production. These features provide early access to upcoming product features, enabling customers to test functionality and provide feedback during the development process.
For more information about the support scope of Red Hat Technology Preview features, see Technology Preview Features Support Scope.
Shared Resource CSI Driver is a Technology Preview feature only. Technology Preview features are not supported with Red Hat production service level agreements (SLAs) and might not be functionally complete. Red Hat does not recommend using them in production. These features provide early access to upcoming product features, enabling customers to test functionality and provide feedback during the development process.
For more information about the support scope of Red Hat Technology Preview features, see Technology Preview Features Support Scope.
Additional resources
5.2. Source-to-image build
Source-to-image (S2I) is a tool for building reproducible container images. It produces ready-to-run images by injecting application source into a container image and assembling a new image. The new image incorporates the base image, the builder, and built source and is ready to use with the buildah run
command. S2I supports incremental builds, which re-use previously downloaded dependencies, previously built artifacts, and so on.
5.2.1. Performing source-to-image incremental builds
Source-to-image (S2I) can perform incremental builds, which means it reuses artifacts from previously-built images.
Procedure
To create an incremental build, create a with the following modification to the strategy definition:
strategy: sourceStrategy: from: kind: "ImageStreamTag" name: "incremental-image:latest" 1 incremental: true 2
- 1
- Specify an image that supports incremental builds. Consult the documentation of the builder image to determine if it supports this behavior.
- 2
- This flag controls whether an incremental build is attempted. If the builder image does not support incremental builds, the build will still succeed, but you will get a log message stating the incremental build was not successful because of a missing
save-artifacts
script.
Additional resources
- See S2I Requirements for information on how to create a builder image supporting incremental builds.
5.2.2. Overriding source-to-image builder image scripts
You can override the assemble
, run
, and save-artifacts
source-to-image (S2I) scripts provided by the builder image.
Procedure
To override the
assemble
,run
, andsave-artifacts
S2I scripts provided by the builder image, complete one of the following actions:-
Provide an
assemble
,run
, orsave-artifacts
script in the.s2i/bin
directory of your application source repository. Provide a URL of a directory containing the scripts as part of the strategy definition in the
BuildConfig
object. For example:strategy: sourceStrategy: from: kind: "ImageStreamTag" name: "builder-image:latest" scripts: "http://somehost.com/scripts_directory" 1
- 1
- The build process appends
run
,assemble
, andsave-artifacts
to the path. If any or all scripts with these names exist, the build process uses these scripts in place of scripts with the same name that are provided in the image.
NoteFiles located at the
scripts
URL take precedence over files located in.s2i/bin
of the source repository.
-
Provide an
5.2.3. Source-to-image environment variables
There are two ways to make environment variables available to the source build process and resulting image: environment files and BuildConfig
environment values. The variables that you provide using either method will be present during the build process and in the output image.
5.2.3.1. Using source-to-image environment files
Source build enables you to set environment values, one per line, inside your application, by specifying them in a .s2i/environment
file in the source repository. The environment variables specified in this file are present during the build process and in the output image.
If you provide a .s2i/environment
file in your source repository, source-to-image (S2I) reads this file during the build. This allows customization of the build behavior as the assemble
script may use these variables.
Procedure
For example, to disable assets compilation for your Rails application during the build:
-
Add
DISABLE_ASSET_COMPILATION=true
in the.s2i/environment
file.
In addition to builds, the specified environment variables are also available in the running application itself. For example, to cause the Rails application to start in development
mode instead of production
:
-
Add
RAILS_ENV=development
to the.s2i/environment
file.
The complete list of supported environment variables is available in the using images section for each image.
5.2.3.2. Using source-to-image build configuration environment
You can add environment variables to the sourceStrategy
definition of the build configuration. The environment variables defined there are visible during the assemble
script execution and will be defined in the output image, making them also available to the run
script and application code.
Procedure
For example, to disable assets compilation for your Rails application:
sourceStrategy: ... env: - name: "DISABLE_ASSET_COMPILATION" value: "true"
Additional resources
- The build environment section provides more advanced instructions.
-
You can also manage environment variables defined in the build configuration with the
oc set env
command.
5.2.4. Ignoring source-to-image source files
Source-to-image (S2I) supports a .s2iignore
file, which contains a list of file patterns that should be ignored. Files in the build working directory, as provided by the various input sources, that match a pattern found in the .s2iignore
file will not be made available to the assemble
script.
5.2.5. Creating images from source code with source-to-image
Source-to-image (S2I) is a framework that makes it easy to write images that take application source code as an input and produce a new image that runs the assembled application as output.
The main advantage of using S2I for building reproducible container images is the ease of use for developers. As a builder image author, you must understand two basic concepts in order for your images to provide the best S2I performance, the build process and S2I scripts.
5.2.5.1. Understanding the source-to-image build process
The build process consists of the following three fundamental elements, which are combined into a final container image:
- Sources
- Source-to-image (S2I) scripts
- Builder image
S2I generates a Dockerfile with the builder image as the first FROM
instruction. The Dockerfile generated by S2I is then passed to Buildah.
5.2.5.2. How to write source-to-image scripts
You can write source-to-image (S2I) scripts in any programming language, as long as the scripts are executable inside the builder image. S2I supports multiple options providing assemble
/run
/save-artifacts
scripts. All of these locations are checked on each build in the following order:
- A script specified in the build configuration.
-
A script found in the application source
.s2i/bin
directory. -
A script found at the default image URL with the
io.openshift.s2i.scripts-url
label.
Both the io.openshift.s2i.scripts-url
label specified in the image and the script specified in a build configuration can take one of the following forms:
-
image:///path_to_scripts_dir
: absolute path inside the image to a directory where the S2I scripts are located. -
file:///path_to_scripts_dir
: relative or absolute path to a directory on the host where the S2I scripts are located. -
http(s)://path_to_scripts_dir
: URL to a directory where the S2I scripts are located.
Script | Description |
---|---|
|
The
|
|
The |
|
The
These dependencies are gathered into a |
|
The |
|
The
Note
The suggested location to put the test application built by your |
Example S2I scripts
The following example S2I scripts are written in Bash. Each example assumes its tar
contents are unpacked into the /tmp/s2i
directory.
assemble
script:
#!/bin/bash # restore build artifacts if [ "$(ls /tmp/s2i/artifacts/ 2>/dev/null)" ]; then mv /tmp/s2i/artifacts/* $HOME/. fi # move the application source mv /tmp/s2i/src $HOME/src # build application artifacts pushd ${HOME} make all # install the artifacts make install popd
run
script:
#!/bin/bash # run the application /opt/application/run.sh
save-artifacts
script:
#!/bin/bash pushd ${HOME} if [ -d deps ]; then # all deps contents to tar stream tar cf - deps fi popd
usage
script:
#!/bin/bash # inform the user how to use the image cat <<EOF This is a S2I sample builder image, to use it, install https://github.com/openshift/source-to-image EOF
Additional resources
5.2.6. Using build volumes
You can mount build volumes to give running builds access to information that you do not want to persist in the output container image.
Build volumes provide sensitive information, such as repository credentials, that the build environment or configuration only needs at build time. Build volumes are different from build inputs, whose data can persist in the output container image.
The mount points of build volumes, from which the running build reads data, are functionally similar to pod volume mounts.
Prerequisites
- You have added an input secret, config map, or both to a BuildConfig object.
Procedure
In the
sourceStrategy
definition of theBuildConfig
object, add any build volumes to thevolumes
array. For example:spec: sourceStrategy: volumes: - name: secret-mvn 1 mounts: - destinationPath: /opt/app-root/src/.ssh 2 source: type: Secret 3 secret: secretName: my-secret 4 - name: settings-mvn 5 mounts: - destinationPath: /opt/app-root/src/.m2 6 source: type: ConfigMap 7 configMap: name: my-config 8 - name: my-csi-volume 9 mounts: - destinationPath: /opt/app-root/src/some_path 10 source: type: CSI 11 csi: driver: csi.sharedresource.openshift.io 12 readOnly: true 13 volumeAttributes: 14 attribute: value
- 1 5 9
- Required. A unique name.
- 2 6 10
- Required. The absolute path of the mount point. It must not contain
..
or:
and does not collide with the destination path generated by the builder. The/opt/app-root/src
is the default home directory for many Red Hat S2I-enabled images. - 3 7 11
- Required. The type of source,
ConfigMap
,Secret
, orCSI
. - 4 8
- Required. The name of the source.
- 12
- Required. The driver that provides the ephemeral CSI volume.
- 13
- Required. This value must be set to
true
. Provides a read-only volume. - 14
- Optional. The volume attributes of the ephemeral CSI volume. Consult the CSI driver’s documentation for supported attribute keys and values.
Shared Resource CSI Driver is a Technology Preview feature only. Technology Preview features are not supported with Red Hat production service level agreements (SLAs) and might not be functionally complete. Red Hat does not recommend using them in production. These features provide early access to upcoming product features, enabling customers to test functionality and provide feedback during the development process.
For more information about the support scope of Red Hat Technology Preview features, see Technology Preview Features Support Scope.
Additional resources
5.3. Custom build
The custom build strategy allows developers to define a specific builder image responsible for the entire build process. Using your own builder image allows you to customize your build process.
A custom builder image is a plain container image embedded with build process logic, for example for building RPMs or base images.
Custom builds run with a high level of privilege and are not available to users by default. Only users who can be trusted with cluster administration permissions should be granted access to run custom builds.
5.3.1. Using FROM image for custom builds
You can use the customStrategy.from
section to indicate the image to use for the custom build.
Procedure
Set the
customStrategy.from
section:strategy: customStrategy: from: kind: "DockerImage" name: "openshift/sti-image-builder"
5.3.2. Using secrets in custom builds
In addition to secrets for source and images that can be added to all build types, custom strategies allow adding an arbitrary list of secrets to the builder pod.
Procedure
To mount each secret at a specific location, edit the
secretSource
andmountPath
fields of thestrategy
YAML file:strategy: customStrategy: secrets: - secretSource: 1 name: "secret1" mountPath: "/tmp/secret1" 2 - secretSource: name: "secret2" mountPath: "/tmp/secret2"
5.3.3. Using environment variables for custom builds
To make environment variables available to the custom build process, you can add environment variables to the customStrategy
definition of the build configuration.
The environment variables defined there are passed to the pod that runs the custom build.
Procedure
Define a custom HTTP proxy to be used during build:
customStrategy: ... env: - name: "HTTP_PROXY" value: "http://myproxy.net:5187/"
To manage environment variables defined in the build configuration, enter the following command:
$ oc set env <enter_variables>
5.3.4. Using custom builder images
OpenShift Container Platform’s custom build strategy enables you to define a specific builder image responsible for the entire build process. When you need a build to produce individual artifacts such as packages, JARs, WARs, installable ZIPs, or base images, use a custom builder image using the custom build strategy.
A custom builder image is a plain container image embedded with build process logic, which is used for building artifacts such as RPMs or base container images.
Additionally, the custom builder allows implementing any extended build process, such as a CI/CD flow that runs unit or integration tests.
5.3.4.1. Custom builder image
Upon invocation, a custom builder image receives the following environment variables with the information needed to proceed with the build:
Variable Name | Description |
---|---|
|
The entire serialized JSON of the |
| The URL of a Git repository with source to be built. |
|
Uses the same value as |
| Specifies the subdirectory of the Git repository to be used when building. Only present if defined. |
| The Git reference to be built. |
| The version of the OpenShift Container Platform master that created this build object. |
| The container image registry to push the image to. |
| The container image tag name for the image being built. |
|
The path to the container registry credentials for running a |
5.3.4.2. Custom builder workflow
Although custom builder image authors have flexibility in defining the build process, your builder image must adhere to the following required steps necessary for running a build inside of OpenShift Container Platform:
-
The
Build
object definition contains all the necessary information about input parameters for the build. - Run the build process.
- If your build produces an image, push it to the output location of the build if it is defined. Other output locations can be passed with environment variables.
5.4. Pipeline build
The Pipeline build strategy is deprecated in OpenShift Container Platform 4. Equivalent and improved functionality is present in the OpenShift Container Platform Pipelines based on Tekton.
Jenkins images on OpenShift Container Platform are fully supported and users should follow Jenkins user documentation for defining their jenkinsfile
in a job or store it in a Source Control Management system.
The Pipeline build strategy allows developers to define a Jenkins pipeline for use by the Jenkins pipeline plugin. The build can be started, monitored, and managed by OpenShift Container Platform in the same way as any other build type.
Pipeline workflows are defined in a jenkinsfile
, either embedded directly in the build configuration, or supplied in a Git repository and referenced by the build configuration.
5.4.1. Understanding OpenShift Container Platform pipelines
The Pipeline build strategy is deprecated in OpenShift Container Platform 4. Equivalent and improved functionality is present in the OpenShift Container Platform Pipelines based on Tekton.
Jenkins images on OpenShift Container Platform are fully supported and users should follow Jenkins user documentation for defining their jenkinsfile
in a job or store it in a Source Control Management system.
Pipelines give you control over building, deploying, and promoting your applications on OpenShift Container Platform. Using a combination of the Jenkins Pipeline build strategy, jenkinsfiles
, and the OpenShift Container Platform Domain Specific Language (DSL) provided by the Jenkins Client Plugin, you can create advanced build, test, deploy, and promote pipelines for any scenario.
OpenShift Container Platform Jenkins Sync Plugin
The OpenShift Container Platform Jenkins Sync Plugin keeps the build configuration and build objects in sync with Jenkins jobs and builds, and provides the following:
- Dynamic job and run creation in Jenkins.
- Dynamic creation of agent pod templates from image streams, image stream tags, or config maps.
- Injection of environment variables.
- Pipeline visualization in the OpenShift Container Platform web console.
- Integration with the Jenkins Git plugin, which passes commit information from OpenShift Container Platform builds to the Jenkins Git plugin.
- Synchronization of secrets into Jenkins credential entries.
OpenShift Container Platform Jenkins Client Plugin
The OpenShift Container Platform Jenkins Client Plugin is a Jenkins plugin which aims to provide a readable, concise, comprehensive, and fluent Jenkins Pipeline syntax for rich interactions with an OpenShift Container Platform API Server. The plugin uses the OpenShift Container Platform command line tool, oc
, which must be available on the nodes executing the script.
The Jenkins Client Plugin must be installed on your Jenkins master so the OpenShift Container Platform DSL will be available to use within the jenkinsfile
for your application. This plugin is installed and enabled by default when using the OpenShift Container Platform Jenkins image.
For OpenShift Container Platform Pipelines within your project, you will must use the Jenkins Pipeline Build Strategy. This strategy defaults to using a jenkinsfile
at the root of your source repository, but also provides the following configuration options:
-
An inline
jenkinsfile
field within your build configuration. -
A
jenkinsfilePath
field within your build configuration that references the location of thejenkinsfile
to use relative to the sourcecontextDir
.
The optional jenkinsfilePath
field specifies the name of the file to use, relative to the source contextDir
. If contextDir
is omitted, it defaults to the root of the repository. If jenkinsfilePath
is omitted, it defaults to jenkinsfile
.
5.4.2. Providing the Jenkins file for pipeline builds
The Pipeline build strategy is deprecated in OpenShift Container Platform 4. Equivalent and improved functionality is present in the OpenShift Container Platform Pipelines based on Tekton.
Jenkins images on OpenShift Container Platform are fully supported and users should follow Jenkins user documentation for defining their jenkinsfile
in a job or store it in a Source Control Management system.
The jenkinsfile
uses the standard groovy language syntax to allow fine grained control over the configuration, build, and deployment of your application.
You can supply the jenkinsfile
in one of the following ways:
- A file located within your source code repository.
-
Embedded as part of your build configuration using the
jenkinsfile
field.
When using the first option, the jenkinsfile
must be included in your applications source code repository at one of the following locations:
-
A file named
jenkinsfile
at the root of your repository. -
A file named
jenkinsfile
at the root of the sourcecontextDir
of your repository. -
A file name specified via the
jenkinsfilePath
field of theJenkinsPipelineStrategy
section of your BuildConfig, which is relative to the sourcecontextDir
if supplied, otherwise it defaults to the root of the repository.
The jenkinsfile
is run on the Jenkins agent pod, which must have the OpenShift Container Platform client binaries available if you intend to use the OpenShift Container Platform DSL.
Procedure
To provide the Jenkins file, you can either:
- Embed the Jenkins file in the build configuration.
- Include in the build configuration a reference to the Git repository that contains the Jenkins file.
Embedded Definition
kind: "BuildConfig" apiVersion: "v1" metadata: name: "sample-pipeline" spec: strategy: jenkinsPipelineStrategy: jenkinsfile: |- node('agent') { stage 'build' openshiftBuild(buildConfig: 'ruby-sample-build', showBuildLogs: 'true') stage 'deploy' openshiftDeploy(deploymentConfig: 'frontend') }
Reference to Git Repository
kind: "BuildConfig"
apiVersion: "v1"
metadata:
name: "sample-pipeline"
spec:
source:
git:
uri: "https://github.com/openshift/ruby-hello-world"
strategy:
jenkinsPipelineStrategy:
jenkinsfilePath: some/repo/dir/filename 1
- 1
- The optional
jenkinsfilePath
field specifies the name of the file to use, relative to the sourcecontextDir
. IfcontextDir
is omitted, it defaults to the root of the repository. IfjenkinsfilePath
is omitted, it defaults tojenkinsfile
.
5.4.3. Using environment variables for pipeline builds
The Pipeline build strategy is deprecated in OpenShift Container Platform 4. Equivalent and improved functionality is present in the OpenShift Container Platform Pipelines based on Tekton.
Jenkins images on OpenShift Container Platform are fully supported and users should follow Jenkins user documentation for defining their jenkinsfile
in a job or store it in a Source Control Management system.
To make environment variables available to the Pipeline build process, you can add environment variables to the jenkinsPipelineStrategy
definition of the build configuration.
Once defined, the environment variables will be set as parameters for any Jenkins job associated with the build configuration.
Procedure
To define environment variables to be used during build, edit the YAML file:
jenkinsPipelineStrategy: ... env: - name: "FOO" value: "BAR"
You can also manage environment variables defined in the build configuration with the oc set env
command.
5.4.3.1. Mapping between BuildConfig environment variables and Jenkins job parameters
When a Jenkins job is created or updated based on changes to a Pipeline strategy build configuration, any environment variables in the build configuration are mapped to Jenkins job parameters definitions, where the default values for the Jenkins job parameters definitions are the current values of the associated environment variables.
After the Jenkins job’s initial creation, you can still add additional parameters to the job from the Jenkins console. The parameter names differ from the names of the environment variables in the build configuration. The parameters are honored when builds are started for those Jenkins jobs.
How you start builds for the Jenkins job dictates how the parameters are set.
-
If you start with
oc start-build
, the values of the environment variables in the build configuration are the parameters set for the corresponding job instance. Any changes you make to the parameters' default values from the Jenkins console are ignored. The build configuration values take precedence. If you start with
oc start-build -e
, the values for the environment variables specified in the-e
option take precedence.- If you specify an environment variable not listed in the build configuration, they will be added as a Jenkins job parameter definitions.
-
Any changes you make from the Jenkins console to the parameters corresponding to the environment variables are ignored. The build configuration and what you specify with
oc start-build -e
takes precedence.
- If you start the Jenkins job with the Jenkins console, then you can control the setting of the parameters with the Jenkins console as part of starting a build for the job.
It is recommended that you specify in the build configuration all possible environment variables to be associated with job parameters. Doing so reduces disk I/O and improves performance during Jenkins processing.
5.4.4. Pipeline build tutorial
The Pipeline build strategy is deprecated in OpenShift Container Platform 4. Equivalent and improved functionality is present in the OpenShift Container Platform Pipelines based on Tekton.
Jenkins images on OpenShift Container Platform are fully supported and users should follow Jenkins user documentation for defining their jenkinsfile
in a job or store it in a Source Control Management system.
This example demonstrates how to create an OpenShift Container Platform Pipeline that will build, deploy, and verify a Node.js/MongoDB
application using the nodejs-mongodb.json
template.
Procedure
Create the Jenkins master:
$ oc project <project_name>
Select the project that you want to use or create a new project with
oc new-project <project_name>
.$ oc new-app jenkins-ephemeral 1
If you want to use persistent storage, use
jenkins-persistent
instead.Create a file named
nodejs-sample-pipeline.yaml
with the following content:NoteThis creates a
BuildConfig
object that employs the Jenkins pipeline strategy to build, deploy, and scale theNode.js/MongoDB
example application.kind: "BuildConfig" apiVersion: "v1" metadata: name: "nodejs-sample-pipeline" spec: strategy: jenkinsPipelineStrategy: jenkinsfile: <pipeline content from below> type: JenkinsPipeline
After you create a
BuildConfig
object with ajenkinsPipelineStrategy
, tell the pipeline what to do by using an inlinejenkinsfile
:NoteThis example does not set up a Git repository for the application.
The following
jenkinsfile
content is written in Groovy using the OpenShift Container Platform DSL. For this example, include inline content in theBuildConfig
object using the YAML Literal Style, though including ajenkinsfile
in your source repository is the preferred method.def templatePath = 'https://raw.githubusercontent.com/openshift/nodejs-ex/master/openshift/templates/nodejs-mongodb.json' 1 def templateName = 'nodejs-mongodb-example' 2 pipeline { agent { node { label 'nodejs' 3 } } options { timeout(time: 20, unit: 'MINUTES') 4 } stages { stage('preamble') { steps { script { openshift.withCluster() { openshift.withProject() { echo "Using project: ${openshift.project()}" } } } } } stage('cleanup') { steps { script { openshift.withCluster() { openshift.withProject() { openshift.selector("all", [ template : templateName ]).delete() 5 if (openshift.selector("secrets", templateName).exists()) { 6 openshift.selector("secrets", templateName).delete() } } } } } } stage('create') { steps { script { openshift.withCluster() { openshift.withProject() { openshift.newApp(templatePath) 7 } } } } } stage('build') { steps { script { openshift.withCluster() { openshift.withProject() { def builds = openshift.selector("bc", templateName).related('builds') timeout(5) { 8 builds.untilEach(1) { return (it.object().status.phase == "Complete") } } } } } } } stage('deploy') { steps { script { openshift.withCluster() { openshift.withProject() { def rm = openshift.selector("dc", templateName).rollout() timeout(5) { 9 openshift.selector("dc", templateName).related('pods').untilEach(1) { return (it.object().status.phase == "Running") } } } } } } } stage('tag') { steps { script { openshift.withCluster() { openshift.withProject() { openshift.tag("${templateName}:latest", "${templateName}-staging:latest") 10 } } } } } } }
- 1
- Path of the template to use.
- 1 2
- Name of the template that will be created.
- 3
- Spin up a
node.js
agent pod on which to run this build. - 4
- Set a timeout of 20 minutes for this pipeline.
- 5
- Delete everything with this template label.
- 6
- Delete any secrets with this template label.
- 7
- Create a new application from the
templatePath
. - 8
- Wait up to five minutes for the build to complete.
- 9
- Wait up to five minutes for the deployment to complete.
- 10
- If everything else succeeded, tag the
$ {templateName}:latest
image as$ {templateName}-staging:latest
. A pipeline build configuration for the staging environment can watch for the$ {templateName}-staging:latest
image to change and then deploy it to the staging environment.
NoteThe previous example was written using the declarative pipeline style, but the older scripted pipeline style is also supported.
Create the Pipeline
BuildConfig
in your OpenShift Container Platform cluster:$ oc create -f nodejs-sample-pipeline.yaml
If you do not want to create your own file, you can use the sample from the Origin repository by running:
$ oc create -f https://raw.githubusercontent.com/openshift/origin/master/examples/jenkins/pipeline/nodejs-sample-pipeline.yaml
Start the Pipeline:
$ oc start-build nodejs-sample-pipeline
NoteAlternatively, you can start your pipeline with the OpenShift Container Platform web console by navigating to the Builds
Pipeline section and clicking Start Pipeline, or by visiting the Jenkins Console, navigating to the Pipeline that you created, and clicking Build Now. Once the pipeline is started, you should see the following actions performed within your project:
- A job instance is created on the Jenkins server.
- An agent pod is launched, if your pipeline requires one.
The pipeline runs on the agent pod, or the master if no agent is required.
-
Any previously created resources with the
template=nodejs-mongodb-example
label will be deleted. -
A new application, and all of its associated resources, will be created from the
nodejs-mongodb-example
template. A build will be started using the
nodejs-mongodb-example
BuildConfig
.- The pipeline will wait until the build has completed to trigger the next stage.
A deployment will be started using the
nodejs-mongodb-example
deployment configuration.- The pipeline will wait until the deployment has completed to trigger the next stage.
-
If the build and deploy are successful, the
nodejs-mongodb-example:latest
image will be tagged asnodejs-mongodb-example:stage
.
-
Any previously created resources with the
The agent pod is deleted, if one was required for the pipeline.
NoteThe best way to visualize the pipeline execution is by viewing it in the OpenShift Container Platform web console. You can view your pipelines by logging in to the web console and navigating to Builds
Pipelines.
5.5. Adding secrets with web console
You can add a secret to your build configuration so that it can access a private repository.
Procedure
To add a secret to your build configuration so that it can access a private repository from the OpenShift Container Platform web console:
- Create a new OpenShift Container Platform project.
- Create a secret that contains credentials for accessing a private source code repository.
- Create a build configuration.
-
On the build configuration editor page or in the
create app from builder image
page of the web console, set the Source Secret. - Click Save.
5.6. Enabling pulling and pushing
You can enable pulling to a private registry by setting the pull secret and pushing by setting the push secret in the build configuration.
Procedure
To enable pulling to a private registry:
- Set the pull secret in the build configuration.
To enable pushing:
- Set the push secret in the build configuration.