bare-operating-system/packages/bare-os-coreutils/lib/summon/summon-http.js

/** HTTP session for summon: redirects, cookies, caps. Uses ctx.httpFetch. */

var BARE_SUMMON_UA = 'Summon/0.1 (Bare OS; text)'
var BARE_SUMMON_MAX_REDIRECTS = 10
var BARE_SUMMON_DEFAULT_TIMEOUT = 20000
var BARE_SUMMON_DEFAULT_MAX_BYTES = 4 * 1024 * 1024

function bareSummonResolveFetch(ctx) {
  if (ctx && typeof ctx.httpFetch === 'function') return ctx.httpFetch
  if (ctx && ctx.bare && typeof ctx.bare.fetch === 'function')
    return ctx.bare.fetch
  if (typeof fetch === 'function') return fetch
  return null
}

function bareSummonHeadersToObject(h) {
  var out = {}
  if (!h) return out
  if (typeof h.forEach === 'function') {
    h.forEach(function (v, k) {
      out[String(k).toLowerCase()] = String(v)
    })
    return out
  }
  var k
  for (k in h) {
    if (Object.prototype.hasOwnProperty.call(h, k))
      out[String(k).toLowerCase()] = String(h[k])
  }
  return out
}

function bareSummonReadSetCookies(headers, res) {
  var out = []
  if (
    res &&
    typeof res.headers !== 'undefined' &&
    res.headers &&
    typeof res.headers.getSetCookie === 'function'
  ) {
    try {
      var g = res.headers.getSetCookie()
      if (Array.isArray(g)) return g
    } catch (e) {
      /* ignore */
    }
  }
  var raw = headers['set-cookie']
  if (!raw) return out
  if (Array.isArray(raw)) return raw
  return [String(raw)]
}

async function bareSummonFetch(ctx, urlStr, opts) {
  opts = opts || {}
  var fn = bareSummonResolveFetch(ctx)
  if (!fn) {
    return { ok: false, error: 'summon: no HTTP client (ctx.httpFetch)' }
  }
  var jar = opts.jar || bareSummonCreateCookieJar()
  var method = String(opts.method || 'GET').toUpperCase()
  var body = opts.body
  var maxRedir =
    opts.maxRedirects != null ? opts.maxRedirects : BARE_SUMMON_MAX_REDIRECTS
  var timeout =
    opts.timeoutMs != null ? opts.timeoutMs : BARE_SUMMON_DEFAULT_TIMEOUT
  var maxBytes =
    opts.maxBytes != null ? opts.maxBytes : BARE_SUMMON_DEFAULT_MAX_BYTES
  var current = urlStr
  var hops = 0
  var lastStatus = 0
  var headersOut = {}
  var text = ''
  var finalUrl = urlStr

  while (hops <= maxRedir) {
    var parsed = bareSummonParseUrl(current)
    if (!parsed || !bareSummonIsHttp(parsed)) {
      return { ok: false, error: 'summon: only http(s) URLs', url: current }
    }
    var hdr = {
      'user-agent': BARE_SUMMON_UA,
      accept: 'text/html,application/xhtml+xml;q=0.9,text/plain;q=0.8,*/*;q=0.1'
    }
    var cookie = jar.headerFor(current)
    if (cookie) hdr.cookie = cookie
    if (opts.headers) {
      var hk
      for (hk in opts.headers) {
        if (Object.prototype.hasOwnProperty.call(opts.headers, hk)) {
          hdr[hk] = opts.headers[hk]
        }
      }
    }
    var ac = null
    var timer = null
    if (typeof AbortController === 'function' && timeout > 0) {
      ac = new AbortController()
      timer = setTimeout(function () {
        try {
          ac.abort()
        } catch (e) {
          /* ignore */
        }
      }, timeout)
    }
    var res
    try {
      res = await fn(current, {
        method: method,
        headers: hdr,
        body: method === 'GET' || method === 'HEAD' ? undefined : body,
        redirect: 'manual',
        signal: ac ? ac.signal : undefined
      })
    } catch (err) {
      if (timer) clearTimeout(timer)
      return {
        ok: false,
        error:
          'summon: request failed: ' + ((err && err.message) || String(err)),
        url: current
      }
    }
    if (timer) clearTimeout(timer)
    lastStatus = res && res.status ? res.status : 0
    headersOut = bareSummonHeadersToObject(res && res.headers)
    var setc = bareSummonReadSetCookies(headersOut, res)
    for (var i = 0; i < setc.length; i++) jar.put(setc[i], current, opts)
    var loc = headersOut.location
    if (loc && lastStatus >= 300 && lastStatus < 400 && hops < maxRedir) {
      var next = bareSummonResolveUrl(loc, current)
      if (!next) break
      if (
        lastStatus === 303 ||
        ((lastStatus === 301 || lastStatus === 302) && method === 'POST')
      ) {
        method = 'GET'
        body = undefined
      }
      current = next.href
      hops++
      continue
    }
    finalUrl = current
    if (typeof res.text === 'function') {
      text = await res.text()
    } else if (typeof res.arrayBuffer === 'function') {
      var ab = await res.arrayBuffer()
      text = new TextDecoder('utf-8', { fatal: false }).decode(
        new Uint8Array(ab)
      )
    }
    if (text && text.length > maxBytes) text = text.slice(0, maxBytes)
    break
  }

  return {
    ok: lastStatus >= 200 && lastStatus < 400,
    status: lastStatus,
    url: finalUrl,
    headers: headersOut,
    body: text,
    jar: jar,
    redirects: hops
  }
}