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mzazrivec/ocm-cli

CLI for the Red Hat OpenShift Cluster Manager

= OCM API Command Line Tools

This project contains the ocm command line tool that simplifies the use
of the OCM API available at api.openshift.com.

== Installation

=== Linux Package Manager
The preferred way to install the tool in Fedora and CentOS is to use the
RPM packages built in https://copr.fedorainfracloud.org/coprs/ocm/tools[Fedora
Copr]. To enable that repository and install the tool use the following commands:

....

dnf copr enable ocm/tools

dnf install ocm-cli

....

This will install the ocm command and will keep it updated using the same
mechanism used to update all the other packages of the distribution.

=== MacOS Brew

....
$ brew tap cblecker/tap
$ brew install ocm
....

=== Build From Source

If you are not using one of these distributions or you don't want to use the RPM
packages then you can alternatively get the release binaries from the GitHub
https://github.com/openshift-online/ocm-cli/releases[releases page]. For
example, to install version 0.1.30 to your personal bin directory you can use
the following commands:

....
$ mkdir -p ~/bin
$ curl -Lo ~/bin/ocm https://github.com/openshift-online/ocm-cli/releases/download/v0.1.30/ocm-linux-amd64
$ chmod +x ~/bin/ocm
....

Finally, if none of the installation options described above work for you then
you can install it using go get:

....
$ go get -u github.com/openshift-online/ocm-cli/cmd/ocm
....

But take into account that the results of installing with go get depend on the
version of Go that you use and on the values of certain environment variables.
It is particularly problematic to install with go get if the version of Go
used doesn't support modules, because the dependencies used may not be the ones
tested by the developers. In general installations done with go get aren't
supported or recommended.

== Activating shell completions

Run the following to see instructions for various shells:

....
$ ocm completion --help
....

== Log In

The first step to use the tool is to log-in with your OpenShift Cluster Manager
offline access token which you can get below:

https://cloud.redhat.com/openshift/token[https://cloud.redhat.com/openshift/token]

To do that use the login command:

....
$ ocm login --token=eyJ...
....

This will use the provided token to request OpenID access and refresh tokens
to sso.redhat.com. The tokens will be saved to the .ocm.json file in your
home directory, for future use.

The login command has options to log-in to other environments. For example,
if you have a service running in your local environment and you want to use the
tool to test it, you can log-in like this:

....
$ ocm login
--token=eyJ...
--url=https://localhost:8000
--insecure
....

NOTE: The insecure option disables verification of TLS certificates and host
names, do not use it in production environments.

== Multiple Concurrent Logins with OCM_CONFIG

An .ocm.json file stores login credentials for a single API gateway. Using
multiple gateways therefore requires having to log in and out a lot or the
ability to utilize multiple config files. The latter functionality is provided
with the OCM_CONFIG environment variable. If running ocm login was
successfull in both cases, the ocm whoami commands will return different
results:

....
$ OCM_CONFIG=$HOME/.ocm.json.prod ocm login --url=production --token=...
(…)
$ OCM_CONFIG=$HOME/.ocm.json.stg ocm login --url=staging --token=...
(…)
$ OCM_CONFIG=$HOME/.ocm.json.prod ocm whoami
(…)
$ OCM_CONFIG=$HOME/.ocm.json.stg ocm whoami
(…)
....

NOTE: Tokens for production and staging will differ.

== Obtaining Tokens

If you need the OpenID access token to use it with some other tool, you can
use the token command:

....
$ ocm token
....

That will print the raw OpenID access token, which you can then use to send
requests to the server with some other tool. For example, if you want to use
https://curl.haxx.se[curl] to retrieve your list of clusters you can do the
following:

....
$ curl
--header "Authorization: Bearer $(ocm token)"
https://api.openshift.com/api/clusters_mgmt/v1/clusters
....

The details of the OpenID access token, in JSON format, can be displayed using
the --payload option:

....
$ ocm token --payload
....

That will display the JSON representation of the access token, which is useful
to diagnose authentication issues.

== Revoking Tokens

If you've compromised your offline token, you can get it revoked like this:

  1. Make sure you're logged into OCM with your browser.
  2. Go https://sso.redhat.com/auth/realms/redhat-external/account/applications[here].
  3. Click REVOKE GRANT for the application cloud-services.

If you now follow the <<_log_in, log in procedure>> new tokens will be generated.

== Log Out

To log out run the logout command:

....
$ ocm logout
....

That will remove the .ocm.json file, so next time you want to use the tool you
will need to log-in again. You can also remove that file manually; the effect is
exactly the same.

== Retrieving Objects

Once logged in you can use the get command to retrieve objects. For example,
to retrieve the list of clusters with a name that starts with my you can use
the following command:

....
$ ocm get /api/clusters_mgmt/v1/clusters --parameter search="name like 'my%'"
....

The --parameter option is used to specify query parameters. It is most useful
combined with the get command, but it can be also used with any other command.
For detailed information about the query parameters supported by each resource
see the https://api.openshift.com[reference documentation].

The search query parameter is specially useful to retrieve objects from
collections that support searching. The syntax of this parameter is similar to
the syntax of the where clause of an SQL statement, but using the names of the
attributes of the object instead of the names of the columns of a table. For
example, in order to retrieve the clusters with a name starting with my and
created in a DNS domain ending with example.com the complete command can be
the following:

....
$ ocm get /api/clusters_mgmt/v1/clusters
--parameter search="name like 'my%' and dns.base_domain like '%.example.com'"
....

To find the AWS regions in the US:

....
$ ocm get /api/clusters_mgmt/v1/cloud_providers/aws/regions
--parameter search="name like 'US %'"
....

To find the clusters created after March 1st 2019:

....
$ ocm get /api/clusters_mgmt/v1/clusters
--parameter search="creation_timestamp >= '2019-03-01'"
....

To find the clusters that are either ready or installing:

....
$ ocm get /api/clusters_mgmt/v1/clusters
--parameter search="state in ('ready', 'installing')"
....

The result of that will be a JSON document containing the description of those
clusters, for example:

[source,json]

{
"kind": "ClusterList",
"page": 1,
"size": 6,
"total": 10
"items": [
{
"kind": "Cluster",
"id": "1GUAUWE3E1IS87Q99M0kxO1LpCG",
"href": "/api/clusters_mgmt/v1/clusters/1GUAUWE3E1IS87Q99M0kxO1LpCG",
"name": "mycluster",
"api": {
"url": "https://mycluster-api.example.com:6443"
},
"console": {
"url": "https://console-openshift-console.apps.mycluster.example.com"
},
...
},
...
]
}

As the server will always return JSON documents it is very convenient to use the
https://stedolan.github.io/jq[jq] tool to extract the information that you
need. For example, if you want to get the list of identifiers of your clusters
you can do the following:

....
$ ocm get /api/clusters_mgmt/v1/clusters | jq -r .items[].id
....

That will return something like this:

....
1FtmglZGw2byDzO8tb2cCtWxCNf
1FtRj13Fz2DIcm4zaDrcLvKAIyf
...
....

The get command can also be used to retrieve information from sub-resources
associated to objects. For example, the credentials of a cluster (SSH keys,
administrator password and kubeconfig) are available in a credentials
sub-resource. So if your cluster identifier is 123 you can retrieve the
credentials with this command:

....
$ ocm get /api/clusters_mgmt/v1/clusters/123/credentials
....

Again the https://stedolan.github.io/jq[jq] tool is very useful here. For
example, it can be used to extract the kubeconfig to a file that can then be
used directly with the oc command:

....
$ # Get the file:
$ ocm get /api/clusters_mgmt/v1/clusters/123/credentials
| jq -r .kubeconfig > mycluster.config

$ # Use it:
$ oc --config=mycluster.config get pods
....

For a complete definition of the types of objects, and their attributes, see the
https://api.openshift.com[reference documentation].

== Creating Objects

To create objects use the post command, and put the JSON representation of the
object either in the standard input or else in a file indicated by the --body
option. For example, to create a new managed cluster prepare a mycluster.json
file with this content:

[source,json]

{
"name": "mycluster",
"flavour": {
"id": "osd-4"
},
"region": {
"id": "us-east-1"
},
"managed": true
}

And then use the post command:

....
$ ocm post /api/clusters_mgmt/v1/clusters < mycluster.json
....

Or with the --body option:

....
$ ocm post /api/clusters_mgmt/v1/clusters --body=mycluster.json
....

That will send the request to the server, which will initiate the process of
creating the object, and will return a JSON document containing the
representation.

Complicated objects, like a cluster, are usually created asynchronously, so the
fact that the server returns a response doesn't mean that the object is ready to
use. Clusters, for example, have a state attribute to indicate that. So after
creating a cluster you will have to periodically check till the cluster is
ready. To do so first get the id returned by the post command:

....
$ ocm post /api/clusters_mgmt/v1/clusters --body=mycluster.json | jq -r .id
....

Then use that identifier to check the value of the state attribute, till it
is ready:

....
$ ocm get /api/clusters_mgmt/v1/clusters/123 | jq -r .state
....

== Deleting Objects

Objects can be deleted using the delete command. For example to delete the
cluster with identifier 123 use the following command:

....
$ ocm delete /api/clusters_mgmt/v1/clusters/123
....

Some objects can be deleted in different ways. For example, a cluster can be
deleted completely, destroying all the virtual machines, disks and any other
resources it uses. But it can also just be deleted from the database while
preserving the virtual machines, disks, etc. To do so the server accepts a
deprovision parameter, which can be true or false. To use it with the tool
add the --parameter option. For example, to delete the cluster with identifier
123 only from the database, use the following command:

....
$ ocm delete /api/clusters_mgmt/v1/clusters/123 --parameter "deprovision=false"
....

Deletion, like creation, is a lengthy process for complicated objects like
clusters, and it happens asynchronously. After the delete command finishes it
will take some time to actually delete the cluster. That can be checking using
the get command till it returns a 404 Not Found response.

== Config

The configuration variables can be read and set via the get and set commands.
These settings will be persisted in the .ocm.json file in your home directory.

....
$ ocm config get url
....

....
$ ocm config set url https://api.openshift.com
....

== Building RPMs

Currently RPMs are built for Fedora and CentOS using
https://copr.fedorainfracloud.org/coprs/ocm/tools[Fedora Copr].

The mechanism selected to do the build is a the following custom script that
generates the RPM .spec file:

[source,bash]

Check that the event payload exists:

if [[ ! -f hook_payload ]]; then
echo "Event payload file 'hook_payload' doesn't exist"
exit 1
fi

Check that the event is the creation of a tag:

ref_type=$(cat hook_payload | jq -r .ref_type)
if [[ "${ref_type}" != "tag" ]]; then
echo "Expected reference type 'tag' but got '${ref_type}'"
exit 1
fi

Check that the tag is well formed:

ref=$(cat hook_payload | jq -r .ref)
if [[ ! "${ref}" =~ ^v[0-9]+.[0-9]+.[0-9]+$ ]]; then
echo "Reference '${ref}' isn't well formed"
exit 1
fi

Set the version to use:

version="${ref:1}"

Generate the .spec file:

cat > ocm-cli.spec <<.
%global debug_package %{nil}

Name: ocm-cli
Version: ${version}
Release: 1%{?dist}
Summary: CLI for the Red Hat OpenShift Cluster Manager
License: ASL 2.0
URL: https://github.com/openshift-online/ocm-cli
Source: https://github.com/openshift-online/ocm-cli/archive/v${version}.tar.gz

BuildRequires: git
BuildRequires: golang-bin

%description
CLI for the Red Hat OpenShift Cluster Manager

%prep
%setup

%build
make

%install
install -m 0755 -d %{buildroot}%{_bindir}
install -m 0755 ocm %{buildroot}%{_bindir}

%files
%license LICENSE.txt
%doc README.adoc
%{_bindir}/*
.

Bye:

exit 0

If this script needs to be changed you will need to go to the copr user
interface and update it manually.

The GitHub repository is configured with a webhook that will trigger the
copr build when a new tag is pushed to the repository.

The build dependencies section of the copr configuration should include the
jq package is it is needed to extract the version number from the payload of
the event sent by the GitHub webhook.

== Extend ocm with plugins

Just like how
https://kubernetes.io/docs/tasks/extend-kubectl/kubectl-plugins/[kubectl
plugins] works, you can write your own ocm plugins and put the binary under the
$PATH directory, the plugin name should be named with prefix ocm-, like
ocm-foo.