functionsMetaData.ts

import { existsSync, readJSON, writeFile } from 'fs-extra'
import { join } from 'pathe'

import { NEXT_PLUGIN, NEXT_PLUGIN_NAME } from '../constants'

import { resolveModuleRoot } from './config'

const getNextRuntimeVersion = async (packageJsonPath: string, useNodeModulesPath: boolean) => {
  if (!existsSync(packageJsonPath)) {
    return
  }

  const packagePlugin = await readJSON(packageJsonPath)

  return useNodeModulesPath ? packagePlugin.version : packagePlugin.dependencies[NEXT_PLUGIN]
}

const PLUGIN_PACKAGE_PATH = '.netlify/plugins/package.json'

const nextPluginVersion = async () => {
  const moduleRoot = resolveModuleRoot(NEXT_PLUGIN)
  const nodeModulesPath = moduleRoot ? join(moduleRoot, 'package.json') : null

  return (
    (await getNextRuntimeVersion(nodeModulesPath, true)) ||
    (await getNextRuntimeVersion(PLUGIN_PACKAGE_PATH, false)) ||
    // The runtime version should always be available, but if it's not, return 'unknown'
    'unknown'
  )
}

export const getPluginVersion = async () => `${NEXT_PLUGIN_NAME}@${await nextPluginVersion()}`

// The information needed to create a function configuration file
export interface FunctionInfo {
  // The name of the function, e.g. `___netlify-handler`
  functionName: string

  // The name of the function that will be displayed in logs, e.g. `Next.js SSR handler`
  functionTitle: string

  // The directory where the function is located, e.g. `.netlify/functions`
  functionsDir: string
}

/**
 * Creates a function configuration file for the given function.
 *
 * @param functionInfo The information needed to create a function configuration file
 */
export const writeFunctionConfiguration = async (functionInfo: FunctionInfo) => {
  const { functionName, functionTitle, functionsDir } = functionInfo
  const generator = await getPluginVersion()

  const metadata = {
    config: {
      name: functionTitle,
      generator,
    },
    version: 1,
  }

  await writeFile(join(functionsDir, functionName, `${functionName}.json`), JSON.stringify(metadata))
}