homebridge-prometheus-exporter/code-generation/config-scheme-gen.js

#!/usr/bin/env node

const { parseSchema } = require('json-schema-to-zod')
const { schema } = require('../config.schema.json')
const { format } = require('prettier')
const { join, basename } = require('path')
const prettierConfig = require('../prettier.config')
const { writeFileSync, readFileSync } = require('fs')

const file = join(__dirname, '../src/generated/config_boundary.ts')

console.log(`Starting code generation for ${file}`)

const zodSchema = parseSchema(schema, false)

const code = format(
    `
// Auto-generated by "${join(basename(__dirname), basename(__filename))}", don’t manually edit

import { z } from 'zod'

export const ConfigBoundary = ${zodSchema}
`,
    { filepath: 'codegen.ts', ...prettierConfig },
)

writeFileSync(file, code)

const note = 'AUTOGENERATED CONFIG DOCS'
const comment = (...strings) => `<!-- ${strings.join(' ')} -->`
const readmePath = join(__dirname, '../README.md')
const readme = readFileSync(readmePath).toString()
const regex = new RegExp(`${comment(note, 'BEGIN')}.*${comment(note, 'END')}`, 'mgs')
if (!readme.match(regex)) {
    console.log('Could not update README.md')
    process.exit(1)
}

writeFileSync(
    readmePath,
    readme.replace(
        regex,
        `${comment(note, 'BEGIN')}\n\`\`\`json5\n${generateDocs(schema)}\n\`\`\`\n${comment(note, 'END')}`,
    ),
)

function generateDocs(schema) {
    const doc = indent(
        Object.entries(schema.properties)
            .map(([property, definition]) => {
                const lines = []

                if (definition.title) {
                    lines.push(`// ${definition.title}`)
                }
                if (definition.description) {
                    lines.push(`//\n// ${wordwrap(definition.description, 80, '\n// ')}`)
                }
                if (definition.default !== undefined) {
                    lines.push(`//\n// Default: ${JSON.stringify(definition.default)}`)
                }

                lines.push(`${JSON.stringify(property)}: ${JSON.stringify('<' + definition.type + '>')}`)

                return lines.join('\n')
            })
            .join(',\n\n\n'),
        6,
    )

    return `{
  // ...
  "platforms": [
    {
      "platform": "PrometheusExporter",


${doc}
    }
  ]
}`
}

function wordwrap(word, length, wrap = '\n') {
    const wrapped = []
    while (word.length > length) {
        const cut = word.substring(0, length)
        const pos = cut.lastIndexOf(' ')
        wrapped.push(cut.substring(0, pos))
        word = word.substring(pos + 1)
    }

    wrapped.push(word)

    return wrapped.join(wrap)
}

function indent(string, indent) {
    return string.replace(/^(.+)$/gm, `${' '.repeat(indent)}$1`)
}

console.log(`Finished code generation for ${file}`)