Helm Diff Plugin
This is a Helm plugin giving you a preview of what a helm upgrade
would change.
It basically generates a diff between the latest deployed version of a release
and a helm upgrade --debug --dry-run
. This can also be used to compare two
revisions/versions of your helm release.
Install
Using Helm plugin manager (> 2.3.x)
helm plugin install https://github.com/databus23/helm-diff
Pre Helm 2.3.0 Installation
Pick a release tarball from the releases page.
Unpack the tarball in your helm plugins directory ($(helm home)/plugins
).
E.g.
curl -L $TARBALL_URL | tar -C $(helm home)/plugins -xzv
From Source
Prerequisites
- GoLang
>= 1.17
Make sure you do not have a version of helm-diff
installed. You can remove it by running helm plugin uninstall diff
Installation Steps
The first step is to download the repository and enter the directory. You can do this via git clone
or downloading and extracting the release. If you clone via git, remember to checkout the latest tag for the latest release.
Next, depending on which helm version you have, install the plugin into helm.
Helm 2
make install
Helm 3
make install/helm3
Usage
The Helm Diff Plugin
* Shows a diff explaining what a helm upgrade would change:
This fetches the currently deployed version of a release
and compares it to a local chart plus values. This can be
used visualize what changes a helm upgrade will perform.
* Shows a diff explaining what had changed between two revisions:
This fetches previously deployed versions of a release
and compares them. This can be used visualize what changes
were made during revision change.
* Shows a diff explaining what a helm rollback would change:
This fetches the currently deployed version of a release
and compares it to the previously deployed version of the release, that you
want to rollback. This can be used visualize what changes a
helm rollback will perform.
Usage:
diff [flags]
diff [command]
Available Commands:
completion Generate the autocompletion script for the specified shell
release Shows diff between release's manifests
revision Shows diff between revision's manifests
rollback Show a diff explaining what a helm rollback could perform
upgrade Show a diff explaining what a helm upgrade would change.
version Show version of the helm diff plugin
Flags:
--allow-unreleased enables diffing of releases that are not yet deployed via Helm
-a, --api-versions stringArray Kubernetes api versions used for Capabilities.APIVersions
--color color output. You can control the value for this flag via HELM_DIFF_COLOR=[true|false]. If both --no-color and --color are unspecified, coloring enabled only when the stdout is a term and TERM is not "dumb"
-C, --context int output NUM lines of context around changes (default -1)
--detailed-exitcode return a non-zero exit code when there are changes
--devel use development versions, too. Equivalent to version '>0.0.0-0'. If --version is set, this is ignored.
--disable-openapi-validation disables rendered templates validation against the Kubernetes OpenAPI Schema
--disable-validation disables rendered templates validation against the Kubernetes cluster you are currently pointing to. This is the same validation performed on an install
--dry-run disables cluster access and show diff as if it was install. Implies --install, --reset-values, and --disable-validation
-D, --find-renames float32 Enable rename detection if set to any value greater than 0. If specified, the value denotes the maximum fraction of changed content as lines added + removed compared to total lines in a diff for considering it a rename. Only objects of the same Kind are attempted to be matched
-h, --help help for diff
--include-tests enable the diffing of the helm test hooks
--install enables diffing of releases that are not yet deployed via Helm (equivalent to --allow-unreleased, added to match "helm upgrade --install" command
--kube-version string Kubernetes version used for Capabilities.KubeVersion
--kubeconfig string This flag is ignored, to allow passing of this top level flag to helm
--no-color remove colors from the output. If both --no-color and --color are unspecified, coloring enabled only when the stdout is a term and TERM is not "dumb"
--no-hooks disable diffing of hooks
--normalize-manifests normalize manifests before running diff to exclude style differences from the output
--output string Possible values: diff, simple, template. When set to "template", use the env var HELM_DIFF_TPL to specify the template. (default "diff")
--post-renderer string the path to an executable to be used for post rendering. If it exists in $PATH, the binary will be used, otherwise it will try to look for the executable at the given path
--post-renderer-args stringArray an argument to the post-renderer (can specify multiple)
--repo string specify the chart repository url to locate the requested chart
--reset-values reset the values to the ones built into the chart and merge in any new values
--reuse-values reuse the last release's values and merge in any new values. If '--reset-values' is specified, this is ignored
--set stringArray set values on the command line (can specify multiple or separate values with commas: key1=val1,key2=val2)
--set-file stringArray set values from respective files specified via the command line (can specify multiple or separate values with commas: key1=path1,key2=path2)
--set-string stringArray set STRING values on the command line (can specify multiple or separate values with commas: key1=val1,key2=val2)
--show-secrets do not redact secret values in the output
--strip-trailing-cr strip trailing carriage return on input
--suppress stringArray allows suppression of the values listed in the diff output
-q, --suppress-secrets suppress secrets in the output
--three-way-merge use three-way-merge to compute patch and generate diff output
-f, --values valueFiles specify values in a YAML file (can specify multiple) (default [])
--version string specify the exact chart version to use. If this is not specified, the latest version is used
Additional help topics:
diff
Use "diff [command] --help" for more information about a command.
Commands:
upgrade:
$ helm diff upgrade -h
Show a diff explaining what a helm upgrade would change.
This fetches the currently deployed version of a release
and compares it to a chart plus values.
This can be used visualize what changes a helm upgrade will
perform.
Usage:
diff upgrade [flags] [RELEASE] [CHART]
Examples:
helm diff upgrade my-release stable/postgresql --values values.yaml
# Set HELM_DIFF_IGNORE_UNKNOWN_FLAGS=true to ignore unknown flags
# It's useful when you're using `helm-diff` in a `helm upgrade` wrapper.
# See https://github.com/databus23/helm-diff/issues/278 for more information.
HELM_DIFF_IGNORE_UNKNOWN_FLAGS=true helm diff upgrade my-release stable/postgres --wait
# Set HELM_DIFF_USE_UPGRADE_DRY_RUN=true to
# use `helm upgrade --dry-run` instead of `helm template` to render manifests from the chart.
# See https://github.com/databus23/helm-diff/issues/253 for more information.
HELM_DIFF_USE_UPGRADE_DRY_RUN=true helm diff upgarde my-release datadog/datadog
# Set HELM_DIFF_THREE_WAY_MERGE=true to
# enable the three-way-merge on diff.
# This is equivalent to specifying the --three-way-merge flag.
# Read the flag usage below for more information on --three-way-merge.
HELM_DIFF_THREE_WAY_MERGE=true helm diff upgarde my-release datadog/datadog
# Set HELM_DIFF_NORMALIZE_MANIFESTS=true to
# normalize the yaml file content when using helm diff.
# This is equivalent to specifying the --normalize-manifests flag.
# Read the flag usage below for more information on --normalize-manifests.
HELM_DIFF_NORMALIZE_MANIFESTS=true helm diff upgrade my-release datadog/datadog
# Set HELM_DIFF_OUTPUT_CONTEXT=n to configure the output context to n lines.
# This is equivalent to specifying the --context flag.
# Read the flag usage below for more information on --context.
HELM_DIFF_OUTPUT_CONTEXT=5 helm diff upgrade my-release datadog/datadog
Flags:
--allow-unreleased enables diffing of releases that are not yet deployed via Helm
-a, --api-versions stringArray Kubernetes api versions used for Capabilities.APIVersions
-C, --context int output NUM lines of context around changes (default -1)
--detailed-exitcode return a non-zero exit code when there are changes
--devel use development versions, too. Equivalent to version '>0.0.0-0'. If --version is set, this is ignored.
--disable-openapi-validation disables rendered templates validation against the Kubernetes OpenAPI Schema
--disable-validation disables rendered templates validation against the Kubernetes cluster you are currently pointing to. This is the same validation performed on an install
--dry-run disables cluster access and show diff as if it was install. Implies --install, --reset-values, and --disable-validation
-D, --find-renames float32 Enable rename detection if set to any value greater than 0. If specified, the value denotes the maximum fraction of changed content as lines added + removed compared to total lines in a diff for considering it a rename. Only objects of the same Kind are attempted to be matched
-h, --help help for upgrade
--include-tests enable the diffing of the helm test hooks
--install enables diffing of releases that are not yet deployed via Helm (equivalent to --allow-unreleased, added to match "helm upgrade --install" command
--kube-version string Kubernetes version used for Capabilities.KubeVersion
--kubeconfig string This flag is ignored, to allow passing of this top level flag to helm
--no-hooks disable diffing of hooks
--normalize-manifests normalize manifests before running diff to exclude style differences from the output
--output string Possible values: diff, simple, template. When set to "template", use the env var HELM_DIFF_TPL to specify the template. (default "diff")
--post-renderer string the path to an executable to be used for post rendering. If it exists in $PATH, the binary will be used, otherwise it will try to look for the executable at the given path
--post-renderer-args stringArray an argument to the post-renderer (can specify multiple)
--repo string specify the chart repository url to locate the requested chart
--reset-values reset the values to the ones built into the chart and merge in any new values
--reuse-values reuse the last release's values and merge in any new values. If '--reset-values' is specified, this is ignored
--set stringArray set values on the command line (can specify multiple or separate values with commas: key1=val1,key2=val2)
--set-file stringArray set values from respective files specified via the command line (can specify multiple or separate values with commas: key1=path1,key2=path2)
--set-string stringArray set STRING values on the command line (can specify multiple or separate values with commas: key1=val1,key2=val2)
--show-secrets do not redact secret values in the output
--strip-trailing-cr strip trailing carriage return on input
--suppress stringArray allows suppression of the values listed in the diff output
-q, --suppress-secrets suppress secrets in the output
--three-way-merge use three-way-merge to compute patch and generate diff output
-f, --values valueFiles specify values in a YAML file (can specify multiple) (default [])
--version string specify the exact chart version to use. If this is not specified, the latest version is used
Global Flags:
--color color output. You can control the value for this flag via HELM_DIFF_COLOR=[true|false]. If both --no-color and --color are unspecified, coloring enabled only when the stdout is a term and TERM is not "dumb"
--no-color remove colors from the output. If both --no-color and --color are unspecified, coloring enabled only when the stdout is a term and TERM is not "dumb"
release:
$ helm diff release -h
This command compares the manifests details of a different releases created from the same chart
It can be used to compare the manifests of
- release1 with release2
$ helm diff release [flags] release1 release2
Example:
$ helm diff release my-prod my-stage
Usage:
diff release [flags] RELEASE release1 [release2]
Flags:
-C, --context int output NUM lines of context around changes (default -1)
--detailed-exitcode return a non-zero exit code when there are changes
-D, --find-renames float32 Enable rename detection if set to any value greater than 0. If specified, the value denotes the maximum fraction of changed content as lines added + removed compared to total lines in a diff for considering it a rename. Only objects of the same Kind are attempted to be matched
-h, --help help for release
--include-tests enable the diffing of the helm test hooks
--normalize-manifests normalize manifests before running diff to exclude style differences from the output
--output string Possible values: diff, simple, template. When set to "template", use the env var HELM_DIFF_TPL to specify the template. (default "diff")
--show-secrets do not redact secret values in the output
--strip-trailing-cr strip trailing carriage return on input
--suppress stringArray allows suppression of the values listed in the diff output
-q, --suppress-secrets suppress secrets in the output
Global Flags:
--color color output. You can control the value for this flag via HELM_DIFF_COLOR=[true|false]. If both --no-color and --color are unspecified, coloring enabled only when the stdout is a term and TERM is not "dumb"
--no-color remove colors from the output. If both --no-color and --color are unspecified, coloring enabled only when the stdout is a term and TERM is not "dumb"
revision:
$ helm diff revision -h
This command compares the manifests details of a named release.
It can be used to compare the manifests of
- latest REVISION with specified REVISION
$ helm diff revision [flags] RELEASE REVISION1
Example:
$ helm diff revision my-release 2
- REVISION1 with REVISION2
$ helm diff revision [flags] RELEASE REVISION1 REVISION2
Example:
$ helm diff revision my-release 2 3
Usage:
diff revision [flags] RELEASE REVISION1 [REVISION2]
Flags:
-C, --context int output NUM lines of context around changes (default -1)
--detailed-exitcode return a non-zero exit code when there are changes
-D, --find-renames float32 Enable rename detection if set to any value greater than 0. If specified, the value denotes the maximum fraction of changed content as lines added + removed compared to total lines in a diff for considering it a rename. Only objects of the same Kind are attempted to be matched
-h, --help help for revision
--include-tests enable the diffing of the helm test hooks
--normalize-manifests normalize manifests before running diff to exclude style differences from the output
--output string Possible values: diff, simple, template. When set to "template", use the env var HELM_DIFF_TPL to specify the template. (default "diff")
--show-secrets do not redact secret values in the output
--strip-trailing-cr strip trailing carriage return on input
--suppress stringArray allows suppression of the values listed in the diff output
-q, --suppress-secrets suppress secrets in the output
Global Flags:
--color color output. You can control the value for this flag via HELM_DIFF_COLOR=[true|false]. If both --no-color and --color are unspecified, coloring enabled only when the stdout is a term and TERM is not "dumb"
--no-color remove colors from the output. If both --no-color and --color are unspecified, coloring enabled only when the stdout is a term and TERM is not "dumb"
rollback:
$ helm diff rollback -h
This command compares the latest manifest details of a named release
with specific revision values to rollback.
It forecasts/visualizes changes, that a helm rollback could perform.
Usage:
diff rollback [flags] [RELEASE] [REVISION]
Examples:
helm diff rollback my-release 2
Flags:
-C, --context int output NUM lines of context around changes (default -1)
--detailed-exitcode return a non-zero exit code when there are changes
-D, --find-renames float32 Enable rename detection if set to any value greater than 0. If specified, the value denotes the maximum fraction of changed content as lines added + removed compared to total lines in a diff for considering it a rename. Only objects of the same Kind are attempted to be matched
-h, --help help for rollback
--include-tests enable the diffing of the helm test hooks
--normalize-manifests normalize manifests before running diff to exclude style differences from the output
--output string Possible values: diff, simple, template. When set to "template", use the env var HELM_DIFF_TPL to specify the template. (default "diff")
--show-secrets do not redact secret values in the output
--strip-trailing-cr strip trailing carriage return on input
--suppress stringArray allows suppression of the values listed in the diff output
-q, --suppress-secrets suppress secrets in the output
Global Flags:
--color color output. You can control the value for this flag via HELM_DIFF_COLOR=[true|false]. If both --no-color and --color are unspecified, coloring enabled only when the stdout is a term and TERM is not "dumb"
--no-color remove colors from the output. If both --no-color and --color are unspecified, coloring enabled only when the stdout is a term and TERM is not "dumb"
Build
Clone the repository into your $GOPATH
and then build it.
$ mkdir -p $GOPATH/src/github.com/databus23/
$ cd $GOPATH/src/github.com/databus23/
$ git clone https://github.com/databus23/helm-diff.git
$ cd helm-diff
$ make install
The above will install this plugin into your $HELM_HOME/plugins
directory.
Prerequisites
- You need to have Go installed. Make sure to set
$GOPATH
Running Tests
Automated tests are implemented with testing.
To run all tests:
go test -v ./...
Release
Bump version
in plugin.yaml
:
$ code plugin.yaml
$ git commit -m 'Bump helm-diff version to 3.x.y'
Set GITHUB_TOKEN
and run:
$ make docker-run-release