openshift-template-tool

OpenShift template tool

This tool is meant to facilitate working with OpenShift templates.

Initially, the tool is able to combine multiple templates into a single unified template.

It can be used in a workflow in which you maintain several small templates for individual components and then automatically generate an all-in-one template to describe a more complex application.

It can also be used as a way to pretty-print templates in a given API version.

See the next sections for details on how to build, test and use the tool.

Building

You will need Go 1.5 or later. If using Go 1.5, set the environment variable GO15VENDOREXPERIMENT=1. Later versions don't need that environment variable and have vendoring support enabled by default.

Using go get

go get github.com/feedhenry/openshift-template-tool

Alternative

Clone this project into a path defined in your GOPATH environment variable.

From the project root where this README.md is located, build using the standard go tool:

cd $GOPATH/src/github.com/feedhenry/openshift-template-tool
go install

Testing

Run tests using the standard go tool:

go test ./template/

Using

It's suggested to add $GOPATH/bin to your PATH environment variable, to make it easier to call the tool by it's name.

That can be accomplished by adding this to your ~/.bashrc:

# Include every ./bin directory from GOPATHs into PATH
export PATH=${GOPATH//://bin:}/bin:$PATH

Then, the tool is available as a regular command:

openshift-template-tool --help

openshift-template-tool merge base-template.json \
                              component-1.json \
                              component-2.json \
                              ... \
                              > merged-template.json

The output of openshift-template-tool merge is a template object that inherits the metadata from the base template, the first command line argument. The lists of objects and parameters from each of the subsequent templates are appended to that of the base template and duplicates are removed.

Verifying your changes before a commit/pull request

To ensure the tool can still be built, all tests pass and Go files are properly formatted, run this command:

./scripts/check

Release procedure

1. Modify VERSION file and commit all changes

vi VERSION
git commit -a -m"Version bump"
git push upstream master

1. Execute build script

./scripts/release

1. Create release in github and attach executables from dist folder.

https://github.com/feedhenry/openshift-template-tool/releases/new

Updating vendored dependencies

This tool depends heavily on openshift/origin. Origin itself depends on several other packages. Some of those packages have patches that don't exist upstream, code that lives only vendored within the Origin code base.

None of the more popular vendoring tools in the Go ecosystem can handle re-vendoring the packages vendored in Origin. We tried using godep and glide, solved error after error, but arrived at no satisfying result.

In essence, what we need is a way to copy all transitive dependencies into a vendor/ subdirectory. With that in mind, we have a script to automate the process.

To update the vendored dependencies:

1. Start from a clean state. Use git status to ensure you have a clean working tree.
2. If you want to base the dependencies on a different version of Origin, edit the scripts/copy-dependencies script and set the value of ORIGIN_TAG to point to the appropriate tag/branch/commit.
3. Run ./scripts/copy-dependencies.
4. Use git status to verify what changes were made.
5. Make sure you can still build the code with go install.
6. Once you are happy with the changes, run git add scripts/copy-dependencies vendor to add the changes to the index, then git commit.

License

The OpenShift template tool is licensed under the Apache License, Version 2.0.