JSON Schema for Humans

Quickly generate a beautiful HTML static page documenting a JSON schema

Features

Support for JSON Schema Draft-07
Since the result is static, it is easier to host and faster to load
Different templates to choose from (See here)
Anchor links, allow to send a user to a specific section of the documentation
Support for references (even circular!)

Installation

pip install json-schema-for-humans

Usage

Options for generation of the doc are documented using this very library

They can be supplied in various ways:

Using a JSON or YAML configuration file with the CLI option --config-file
Using the CLI option --config
Using a ConfigurationOption from code

More details are available in the appropriate sections below.

From CLI

generate-schema-doc [OPTIONS] SCHEMA_FILE [RESULT_FILE]

SCHEMA_FILE must be a valid JSON Schema (in JSON or YAML format)

The default value for RESULT_FILE is schema_doc.html

CLI options

--config

Supply generation config parameters. The parameters are documented in the JSON schema config_schema.json at the root of the repo or see the generated doc.

Each parameter is in the format --config parameter_name=parameter_value. Example: --config expand_buttons=true. The parameter value must be valid JSON.

For flags, you can also omit the value for true or prefix the parameter name with no_ for false. Example: --config expand_buttons or --config no_expand_buttons.

--config-file

Path to a JSON or YAML configuration file respecting the schema config_schema.json.

Example: --config-file jsfh-conf.yaml where jsfh-conf.yaml is in the current directory and contains the following:

description_is_markdown: false
expand_buttons: true
copy_js: false

From code

There are 3 methods that one could use:

Method Name	Schema input	Output	CSS and JS copied?
generate_from_schema	`schema_file` as str, Path (from pathlib) or a file object	Rendered HTML as a str	No
generate_from_filename	`schema_file_name` as a str or Path	Rendered HTML written to the file at path `result_file_name`	Yes
generate_from_file_object	`schema_file` as an open file object (read mode)	Rendered HTML written to the file at `result_file`, which must be an open file object (in write mode)	Yes

Notes:

When using file objects, it is assumed that files are opened with encoding "utf-8"
CSS and JS files are copied to the current working directory with names "schema_doc.css" and "schema_doc.min.js" respectively
Other parameters of these methods are analogous to the CLI parameters documented above.

The GenerationConfiguration object

To reduce the number of parameters to pass from function to function in the code, there is a GenerationConfiguration object that should be used for providing options.

Example:

from json_schema_for_humans.generate import GenerationConfiguration, generate_from_filename


config = GenerationConfiguration(copy_css=False, expand_buttons=True)

generate_from_filename("my_schema.json", "schema_doc.html", config=config)

# Your doc is now in a file named "schema_doc.html". Next to it, "schema_doc.min.js" was copied, but not "schema_doc.css"
# Your doc will contain a "Expand all" and a "Collapse all" button at the top

Pre-load schemas

generate_from_schema has a loaded_schemas parameter that can be used to pre-load schemas. This must be a dict with the key being the real path of the schema file and the value being the result of loading the schema (with json.load or yaml.safe_load, for example).

This should not be necessary in normal scenarios.

What's supported

See the excellent Understanding JSON Schema to understand what are those checks

The following are supported:

Types
Regular expressions
String length
Numeric types multiples and range
Constant and enumerated values
Required properties
Pattern properties
Default values
Array minItems, maxItems, uniqueItems, items (schema that must apply to all of the array items), and contains
Combining schema with oneOf, allOf, anyOf, and not
Examples
Conditional subschemas

These are not supported at the moment (PRs welcome!):

String format
Property names and size
Array items at specific index (for example, first item must be a string and second must be an integer)
Property dependencies
Media

References

References are supported:

To another part of the schema, e.g. { $ref: "#/definitions/something" }
To a local file, {"$ref": "references.json"}, {"$ref": "references.json#/definitions/something"}
To a URL, {"$ref": "http://example.com/schema.json"}, {"$ref": "http://example.com/schema.json#/definitions/something"}

You can have a description next to a $ref, it will be displayed in priority to the description from the referenced element.

If you have several attributes using the same definition, the definition will only be rendered once. All other usages of the same definition will be replaced with an anchor link to the first render of the definition. This can be turned off using --config no_link_to_reused_ref. See With references in the examples.

Templates

Templates control the style of the generated documentation.

js

This is the default template. It uses Bootstrap along with minimal Javascript to allow for the following:

Properties are in expandable dynamic sections. You can include a button to expand or collapse all. (See here)
Conditional subschemas (anyOf, oneOf, allOf) are in tabbed sections
Anchor links will scroll to, expand, and animate the target section
Long descriptions are collapsed by default

When using this template, you need to include the Javascript file (schema_doc.min.js) that is automatically copied next to the output HTML file (schema_doc.html by default).

flat

Note: This template is a work in progress

It is sometimes not possible or desirable to include custom Javascript in documentation. This template addresses this issue by removing interactive elements in favor of simpler HTML.

At the moment, this means the whole documentation is generated without any collapsible sections, which may make it hard to understand the schema structure. Contributions are welcomed to improve it!

Contributing

See CONTRIBUTING.md

azaroth42/json-schema-for-humans