j2udev / readme-generator-for-helm

Auto generate READMEs for Helm Charts

Readme Generator For Helm

This tool is forked from bitnami labs. Please see their README for more detailed information. This fork adds the ability to specify an environment variable column and also adds a check modifier to inform users to visit the values.yaml for the default value of more involved parameters.

TLDR

Install this tool with npm:

npm install -g https://github.com/j2udevelopment/readme-generator-for-helm

It can be run with environment variable support

readme-generator -r README.md -v values.yaml -e

or without

readme-generator -r README.md -v values.yaml

If you use the environment variable flag, you just need to specify an additional argument for each respective parameter, i.e.

## @param my-custom-param.foo MY_CUSTOM_FOO_VAR [optional modifier] My foo parameter description
## @param my-custom-param.bar MY_CUSTOM_BAR_VAR [optional modifier] My bar parameter description
##
my-custom-param:
  foo: bar
  bar: baz

If your parameter isn't associated with an environment variable, just use N/A

## @param my-custom-param.foo N/A [optional modifier] My foo parameter description
## @param my-custom-param.bar N/A [optional modifier] My bar parameter description
##
my-custom-param:
  foo: bar
  bar: baz

The modifiers will affect what is added to the default value column for params that don't necessarily have a default value, or that have a value too complicated for a simple markdown table cell. The available modifiers are array, object, string, or check.

---

Autogenerate Helm Charts READMEs' tables based on values YAML file metadata.

How it works

The tools expects some metadata for the descriptions in the provided values.yaml file. It will parse and check the metadata against the real values. If the metadata is consistent with the real values, it will generate and insert the values table into the provided README.md file. If the metadata is not correct it will print the full list of errors. It checks whether there are metadata for non existing values or there are missing metadata for an existing value.

The table that will be inserted into the readme.md will have the following structure:

## Parameters

### Section 1 title

| Name      | Description             | Default        |
|:----------|:------------------------|:---------------|
| `value_1` | Description for value 1 | `defaultValue` |
| `value_2` | Description for value 2 | `defaultValue` |
| `value_3` | Description for value 3 | `defaultValue` |

### Section 2 title

| Name      | Description             | Default        |
|:----------|:------------------------|:---------------|
| `value_1` | Description for value 1 | `defaultValue` |
| `value_2` | Description for value 2 | `defaultValue` |
| `value_3` | Description for value 3 | `defaultValue` |

...

The number of # characters needed for the sections title is dynamically calculated, and the title of the Parameters section can be configured via the configuration file.

Requirements

The project has been developed and tested with node version 12.21.0.

Install

Execute the following commands to install the tool:

git clone https://github.com/bitnami-labs/readme-generator-for-helm
npm install -g readme-generator-for-helm

Test

We use Jest to implement the tests. In order to test your changes execute the following command:

npm run-script test

Basic usage

Usage: readme-generator [options]

Options:
  -r, --readme <path>   Path to the README.md file
  -v, --values <path>   Path to the values.yaml file
  -c, --config <path>   Path to the config file
  -m, --metadata <path> Path to the metadata file
  -h, --help            display help for command

Metadata

For the tool to work, you need to add some metadata to your values.yaml file.

By default we use a format similar to Javadoc, using @xxx for tags followed by the tag structure.

The following are the tags supported at this very moment:

• For a parameter: ## @param (fullKeyPath) [modifier?] Description.
• For a section: ## @section Section Title".
• To skip an object and all its childrens: ## @skip fullKeyPath.

All the tags as well as the two initial # characters for the comments style can be configured in the configuration file.

IMPORTANT: tags' order or position in the file is NOT important except for the @section tag. The @section that will include in the section all the parameters after it until a new section is found or the file ends.

The modifier is optional and it will let you override the value of an object. Currently there two modifiers supported:

• [array] Indicates that the value of the parameter must be set to [].
• [object] Indicates that the value of the parameter must be set to {}.
• [string] Indicates that the value of the parameter must be set to "".
• [check] Indicates that the value of the parameter can be obtained in the chart's values.yaml file, useful for long strings or arrays.

The modifiers are also customizable via the configuration file.

Configuration file

The configuration file has the following structure:

{
  "comments": {
    "format": "##"                       <-- Which is the comments format in the values YAML
  },
  "tags": {
    "param": "@param",                   <-- Tag that indicates a parameter
    "section": "@section",               <-- Tag that indicates a section
    "skip": "@skip"                      <-- Tag that indicates the object must be skipped
  },
  "modifiers": {
    "array": "array",                    <-- Modifier that indicates an array type
    "object": "object"                   <-- Modifier that indicates an object type
    "string": "string"                   <-- Modifier that indicates an string type
    "check": "check"                     <-- Modifier that indicates to check the real value at the values.yaml
  },
  "regexp": {
    "paramsSectionTitle": "Parameters"   <-- Title of the parameters section to replace in the README.md
  }
}

Generate values.yaml Schema

The readme-generator-for-helm can also use the metadata in the values.yaml to generate an schemaObject as output by using the --metadata option. File generated will be a JSON file formated according to the OpenAPIv3 SchemaObject definition.