Previous control plane versions do not provide an 'install' config, so
this field cannot be required.
Now, missing empty are handled more gracefully; and upgrade repairs
install configs with missing fields.
The `install` command errors when the deploy target contains an existing
Linkerd deployment. The `upgrade` command is introduced to reinstall or
reconfigure the Linkerd control plane.
Upgrade works as follows:
1. The controller config is fetched from the Kubernetes API. The Public
API is not used, because we need to be able to reinstall the control
plane when the Public API is not available; and we are not concerned
about RBAC restrictions preventing the installer from reading the
config (as we are for inject).
2. The install configuration is read, particularly the flags used during
the last install/upgrade. If these flags were not set again during the
upgrade, the previous values are used as if they were passed this time.
The configuration is updated from the combination of these values,
including the install configuration itself.
Note that some flags, including the linkerd-version, are omitted
since they are stored elsewhere in the configurations and don't make
sense to track as overrides..
3. The issuer secrets are read from the Kubernetes API so that they can
be re-used. There is currently no way to reconfigure issuer
certificates. We will need to create _another_ workflow for
updating these credentials.
4. The install rendering is invoked with values and config fetched from
the cluster, synthesized with the new configuration.
When installing Linkerd, a user may override default settings, or may
explicitly configure defaults. Consider install options like `--ha
--controller-replicas=4` -- the `--ha` flag sets a new default value for
the controller-replicas, and then we override it.
When we later upgrade this cluster, how can we know how to configure the
cluster?
We could store EnableHA and ControllerReplicas configurations in the
config, but what if, in a later upgrade, the default value changes? How
can we know whether the user specified an override or just used the
default?
To solve this, we add an `Install` message into a new config.
This message includes (at least) the CLI flags used to invoke
install.
upgrade does not specify defaults for install/proxy-options fields and,
instead, uses the persisted install flags to populate default values,
before applying overrides from the upgrade invocation.
This change breaks the protobuf compatibility by altering the
`installation_uuid` field introduced in 9c442f6885.
Because this change was not yet released (even in an edge release), we
feel that it is safe to break.
Fixes https://github.com/linkerd/linkerd2/issues/2574
- Created the pkg/inject package to hold the new injection shared lib.
- Extracted from `/cli/cmd/inject.go` and `/cli/cmd/inject_util.go`
the core methods doing the workload parsing and injection, and moved them into
`/pkg/inject/inject.go`. The CLI files should now deal only with
strictly CLI concerns, and applying the json patch returned by the new
lib.
- Proceeded analogously with `/cli/cmd/uninject.go` and
`/pkg/inject/uninject.go`.
- The `InjectReport` struct and helping methods were moved into
`/pkg/inject/report.go`
- Refactored webhook to use the new injection lib
- Removed linkerd-proxy-injector-sidecar-config ConfigMap
- Added the ability to add pod labels and annotations without having to
specify the already existing ones
Fixes#1748, #2289
Signed-off-by: Alejandro Pedraza <alejandro.pedraza@gmail.com>
Katerina
Andrew Seigner
Oliver Gould
Alejandro Pedraza