This commits adds `LoadChartMetadataFromArchive` and
`LoadChartMetadataFromDir` helpers to the internal `helm` package
to be able to make observations to the Helm metadata file without
loading the chart in full.

The helpers are compatible with charts of the v1 format (with a
separate `requirements.yaml` file), and an additional
`LoadChartMetadata` helper is available to automatically call the
right `LoadChartMetadataFrom*` version by looking at the file
description of the given path.

Signed-off-by: Hidde Beydals <hello@hidde.co>

This commits adds simple caching capabilities to the
`ChartRepository`, which makes it possible to load the `Index` from a
defined `CachePath` using `LoadFromCache()`, and to download the index
to a new `CachePath` using `CacheIndex()`.

In addition, the repository tests have been updated to make use of
Gomega, and some missing ones have been added.

Signed-off-by: Hidde Beydals <hello@hidde.co>

This commit starts with the optimization of the `DepenendencyManager`,
ensuring the chart indexes are lazy loaded, and replacing the
(limitless) concurrency with a configurable number of workers with a
default of 1.

Signed-off-by: Hidde Beydals <hello@hidde.co>

This commit starts with the creation of a `ChartBuilder` to facilitate
the (conditional) build of a chart outside of the reconciler logic.

The builder can be configured with a set of (modifying) options, which
define together with the type of chart source what steps are taken
during the build.

To better facilitate the builder's needs and attempt to be more
efficient, changes have been made to the `DependencyBuilder` and
`ChartRepository` around (order of) operations and/or lazy-load
capabilities.

Signed-off-by: Hidde Beydals <hello@hidde.co>

This wires the `ChartRepository` changes into the reconciler to ensure
it works.

Signed-off-by: Hidde Beydals <hello@hidde.co>

This commit refactors the `ChartBuilder` that used to be a do-it-all
struct into an interace with two implementations:

- `LocalChartBuilder`: to build charts from a source on the local
  filesystem, either from a directory or from a packaged chart.
- `RemoteChartBuilder`: to build charts from a remote Helm repository
  index.

The new logic within the builders validates the size of the Helm size
it works with based on the `Max*Size` global variables in the internal
`helm` package, to address the recommendation from the security audit.

In addition, changes `ClientOptionsFromSecret` takes now a directory
argument which temporary files are placed in, making it easier to
perform a garbage collection of the whole directory at the end of a
reconcile run.

Signed-off-by: Hidde Beydals <hello@hidde.co>

This commit starts wiring the factored out Helm chart build logic into
the reconciler to ensure, validating the API capabilities.

Signed-off-by: Hidde Beydals <hello@hidde.co>

With all the logic that used to reside in the `controllers` package
factored into this package, it became cluttered. This commit tries to
bring a bit more structure in place.

Signed-off-by: Hidde Beydals <hello@hidde.co>

Dealing with some loose ends around making observations, and code
style.

The loaded byes of a chart are used as a revision to ensure e.g.
periodic builds with unstable ordering of items do not trigger a false
positive.

Signed-off-by: Hidde Beydals <hello@hidde.co>

Add more chart local builder and dependency manager tests.

Signed-off-by: Sunny <darkowlzz@protonmail.com>

- For remote builds, if the build option has a version metadata, the
  chart should be repackaged with the provided version.
- Update internal/helm/testdata/charts/helmchart-0.1.0.tgz to include
  value files for testing merge chart values.

Signed-off-by: Sunny <darkowlzz@protonmail.com>

Cached chart build tests for both local and remote builder.

Signed-off-by: Sunny <darkowlzz@protonmail.com>

This makes the string less verbose and deals with the safe handling
of some edge-case build states.

Signed-off-by: Hidde Beydals <hello@hidde.co>

Signed-off-by: Hidde Beydals <hello@hidde.co>

This commit introduces a typed `BuildError` to be returned by
`Builder.Build` in case of a failure.

The `Reason` field in combination with `BuildErrorReason` can be used
to signal (or determine) the reason of a returned error within the
context of the build process.

At present this is used to determine the correct Condition Reason, but
in a future iteration this can be used to determine the negative
polarity condition that should be set to indicate a precise failure to
the user.

Signed-off-by: Hidde Beydals <hello@hidde.co>

This includes a change of the defaults to more acceptible (higher)
values.

Signed-off-by: Sunny <darkowlzz@protonmail.com>

Previous usage while consistent, was incorrect, and inconsitent with
the field in the API spec.

Signed-off-by: Hidde Beydals <hello@hidde.co>

This allows custom configuration of the Helm file read limits, allowing
a user to overwrite them to their likenings if the defaults are too
restrictive for their specific setup using arguments:

`--helm-{index,chart,chart-file}-max-size`

Signed-off-by: Hidde Beydals <hello@hidde.co>

- Add some more documentation around chart builders
- Ensure correct indentation in some doc comments
- Provide example of using `errors.Is` for typed `BuildError`
- Mention "bytes" in file size limit errors
- Add missing copyright header

Signed-off-by: Hidde Beydals <hello@hidde.co>

This makes it possible to signal reference (validation) errors
happening before the build process actually starts dealing with
the chart.

At present, this does not have a more specific counterpart in the API,
but this is expected to change when the conditions logic is revised.

Signed-off-by: Hidde Beydals <hello@hidde.co>

By providing the Generation of the object that is getting reconciled
as version metadata to the builder if any custom values files are
defined, the Artifact revision changes if the specification does,
ensuring consumers of the Artifact are able to react to changes in
values (and perform a release).

Signed-off-by: Hidde Beydals <hello@hidde.co>

This helps detect e.g. path or chart name reference changes.

Signed-off-by: Hidde Beydals <hello@hidde.co>

Signed-off-by: Hidde Beydals <hello@hidde.co>