sapper2openapi.mjs

import { manifest } from '@sapper/internal/manifest-server'

export const definition = () => {
  const openapi = { openapi: '3.0.0', paths: {} }
  const routes = manifest.server_routes
  for (const route of routes) {
    const pattern = route.pattern.toString()
    let name = pattern.replace('^\\/', '').replace('\\/?$/', '')
    let params
    if (name.endsWith('\\/([^/]+?)')) {
      let prms = '/foo'
      name = name.replace('\\/([^/]+?)', '')
      while (name.endsWith('\\/([^/]+?)')) {
        name = name.replace('\\/([^/]+?)', '')
        prms += '/foo'
      }
      name = name.replace(/\\/gm, '')
      params = route.params(route.pattern.exec(name + prms))
    }
    name = name.replace(/\\/gm, '')
    for (const method of Object.keys(route.handlers)) {
      // last will win
      //if (!openapi.paths[name])
      openapi.paths[name] = {}
      //if (!openapi.paths[name][method])
      openapi.paths[name][method] = { parameters: [] }
      openapi.paths[name][method].responses = { 200: { description: 'Default response' } }
      if (params) {
        for (const param of Object.keys(params)) {
          openapi.paths[name][method].parameters.push({
            name: param,
            schema: {
              type: 'string',
            },
            in: 'path',
            required: true,
          })
        }
      } // else { // allow mix path and query
      let sc = route.handlers[method].toString().split('\n')
      const matchfuncparams = /\((\b\w*\b),(\b\w*\b),(\b\w*\b)\)\{/
      const maybe = matchfuncparams.exec(sc[0].replace(/\s/g, ''))
      let req
      if (maybe && maybe[1]) {
        req = maybe[1]
        sc.shift()
        const matchspread = new RegExp('{(.*)}=' + req + '.query')
        let prms
        for (const l of sc) {
          const maybe = matchspread.exec(l.replace(/\s/g, ''))
          if (maybe && maybe[1]) {
            prms = maybe[1].split(',')
            break
          }
        }
        if (prms) {
          for (const param of prms) {
            openapi.paths[name][method].parameters.push({
              name: param,
              schema: {
                type: 'string',
              },
              in: 'query',
              required: false,
            })
          }
        }
      }
    }
  }
  return openapi
}