Adding upstream version 5.28.2+dfsg1+~cs23.11.12.3.upstream/5.28.2+dfsg1+_cs23.11.12.3upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

5 files changed, 1492 insertions, 0 deletions

diff --git a/lib/core/connect.js b/lib/core/connect.js
new file mode 100644
index 0000000..3309117
--- /dev/null
+++ b/lib/core/connect.js
@@ -0,0 +1,189 @@
+'use strict'
+
+const net = require('net')
+const assert = require('assert')
+const util = require('./util')
+const { InvalidArgumentError, ConnectTimeoutError } = require('./errors')
+
+let tls // include tls conditionally since it is not always available
+
+// TODO: session re-use does not wait for the first
+// connection to resolve the session and might therefore
+// resolve the same servername multiple times even when
+// re-use is enabled.
+
+let SessionCache
+// FIXME: remove workaround when the Node bug is fixed
+// https://github.com/nodejs/node/issues/49344#issuecomment-1741776308
+if (global.FinalizationRegistry && !process.env.NODE_V8_COVERAGE) {
+  SessionCache = class WeakSessionCache {
+    constructor (maxCachedSessions) {
+      this._maxCachedSessions = maxCachedSessions
+      this._sessionCache = new Map()
+      this._sessionRegistry = new global.FinalizationRegistry((key) => {
+        if (this._sessionCache.size < this._maxCachedSessions) {
+          return
+        }
+
+        const ref = this._sessionCache.get(key)
+        if (ref !== undefined && ref.deref() === undefined) {
+          this._sessionCache.delete(key)
+        }
+      })
+    }
+
+    get (sessionKey) {
+      const ref = this._sessionCache.get(sessionKey)
+      return ref ? ref.deref() : null
+    }
+
+    set (sessionKey, session) {
+      if (this._maxCachedSessions === 0) {
+        return
+      }
+
+      this._sessionCache.set(sessionKey, new WeakRef(session))
+      this._sessionRegistry.register(session, sessionKey)
+    }
+  }
+} else {
+  SessionCache = class SimpleSessionCache {
+    constructor (maxCachedSessions) {
+      this._maxCachedSessions = maxCachedSessions
+      this._sessionCache = new Map()
+    }
+
+    get (sessionKey) {
+      return this._sessionCache.get(sessionKey)
+    }
+
+    set (sessionKey, session) {
+      if (this._maxCachedSessions === 0) {
+        return
+      }
+
+      if (this._sessionCache.size >= this._maxCachedSessions) {
+        // remove the oldest session
+        const { value: oldestKey } = this._sessionCache.keys().next()
+        this._sessionCache.delete(oldestKey)
+      }
+
+      this._sessionCache.set(sessionKey, session)
+    }
+  }
+}
+
+function buildConnector ({ allowH2, maxCachedSessions, socketPath, timeout, ...opts }) {
+  if (maxCachedSessions != null && (!Number.isInteger(maxCachedSessions) || maxCachedSessions < 0)) {
+    throw new InvalidArgumentError('maxCachedSessions must be a positive integer or zero')
+  }
+
+  const options = { path: socketPath, ...opts }
+  const sessionCache = new SessionCache(maxCachedSessions == null ? 100 : maxCachedSessions)
+  timeout = timeout == null ? 10e3 : timeout
+  allowH2 = allowH2 != null ? allowH2 : false
+  return function connect ({ hostname, host, protocol, port, servername, localAddress, httpSocket }, callback) {
+    let socket
+    if (protocol === 'https:') {
+      if (!tls) {
+        tls = require('tls')
+      }
+      servername = servername || options.servername || util.getServerName(host) || null
+
+      const sessionKey = servername || hostname
+      const session = sessionCache.get(sessionKey) || null
+
+      assert(sessionKey)
+
+      socket = tls.connect({
+        highWaterMark: 16384, // TLS in node can't have bigger HWM anyway...
+        ...options,
+        servername,
+        session,
+        localAddress,
+        // TODO(HTTP/2): Add support for h2c
+        ALPNProtocols: allowH2 ? ['http/1.1', 'h2'] : ['http/1.1'],
+        socket: httpSocket, // upgrade socket connection
+        port: port || 443,
+        host: hostname
+      })
+
+      socket
+        .on('session', function (session) {
+          // TODO (fix): Can a session become invalid once established? Don't think so?
+          sessionCache.set(sessionKey, session)
+        })
+    } else {
+      assert(!httpSocket, 'httpSocket can only be sent on TLS update')
+      socket = net.connect({
+        highWaterMark: 64 * 1024, // Same as nodejs fs streams.
+        ...options,
+        localAddress,
+        port: port || 80,
+        host: hostname
+      })
+    }
+
+    // Set TCP keep alive options on the socket here instead of in connect() for the case of assigning the socket
+    if (options.keepAlive == null || options.keepAlive) {
+      const keepAliveInitialDelay = options.keepAliveInitialDelay === undefined ? 60e3 : options.keepAliveInitialDelay
+      socket.setKeepAlive(true, keepAliveInitialDelay)
+    }
+
+    const cancelTimeout = setupTimeout(() => onConnectTimeout(socket), timeout)
+
+    socket
+      .setNoDelay(true)
+      .once(protocol === 'https:' ? 'secureConnect' : 'connect', function () {
+        cancelTimeout()
+
+        if (callback) {
+          const cb = callback
+          callback = null
+          cb(null, this)
+        }
+      })
+      .on('error', function (err) {
+        cancelTimeout()
+
+        if (callback) {
+          const cb = callback
+          callback = null
+          cb(err)
+        }
+      })
+
+    return socket
+  }
+}
+
+function setupTimeout (onConnectTimeout, timeout) {
+  if (!timeout) {
+    return () => {}
+  }
+
+  let s1 = null
+  let s2 = null
+  const timeoutId = setTimeout(() => {
+    // setImmediate is added to make sure that we priotorise socket error events over timeouts
+    s1 = setImmediate(() => {
+      if (process.platform === 'win32') {
+        // Windows needs an extra setImmediate probably due to implementation differences in the socket logic
+        s2 = setImmediate(() => onConnectTimeout())
+      } else {
+        onConnectTimeout()
+      }
+    })
+  }, timeout)
+  return () => {
+    clearTimeout(timeoutId)
+    clearImmediate(s1)
+    clearImmediate(s2)
+  }
+}
+
+function onConnectTimeout (socket) {
+  util.destroy(socket, new ConnectTimeoutError())
+}
+
+module.exports = buildConnector
diff --git a/lib/core/errors.js b/lib/core/errors.js
new file mode 100644
index 0000000..7af704b
--- /dev/null
+++ b/lib/core/errors.js
@@ -0,0 +1,230 @@
+'use strict'
+
+class UndiciError extends Error {
+  constructor (message) {
+    super(message)
+    this.name = 'UndiciError'
+    this.code = 'UND_ERR'
+  }
+}
+
+class ConnectTimeoutError extends UndiciError {
+  constructor (message) {
+    super(message)
+    Error.captureStackTrace(this, ConnectTimeoutError)
+    this.name = 'ConnectTimeoutError'
+    this.message = message || 'Connect Timeout Error'
+    this.code = 'UND_ERR_CONNECT_TIMEOUT'
+  }
+}
+
+class HeadersTimeoutError extends UndiciError {
+  constructor (message) {
+    super(message)
+    Error.captureStackTrace(this, HeadersTimeoutError)
+    this.name = 'HeadersTimeoutError'
+    this.message = message || 'Headers Timeout Error'
+    this.code = 'UND_ERR_HEADERS_TIMEOUT'
+  }
+}
+
+class HeadersOverflowError extends UndiciError {
+  constructor (message) {
+    super(message)
+    Error.captureStackTrace(this, HeadersOverflowError)
+    this.name = 'HeadersOverflowError'
+    this.message = message || 'Headers Overflow Error'
+    this.code = 'UND_ERR_HEADERS_OVERFLOW'
+  }
+}
+
+class BodyTimeoutError extends UndiciError {
+  constructor (message) {
+    super(message)
+    Error.captureStackTrace(this, BodyTimeoutError)
+    this.name = 'BodyTimeoutError'
+    this.message = message || 'Body Timeout Error'
+    this.code = 'UND_ERR_BODY_TIMEOUT'
+  }
+}
+
+class ResponseStatusCodeError extends UndiciError {
+  constructor (message, statusCode, headers, body) {
+    super(message)
+    Error.captureStackTrace(this, ResponseStatusCodeError)
+    this.name = 'ResponseStatusCodeError'
+    this.message = message || 'Response Status Code Error'
+    this.code = 'UND_ERR_RESPONSE_STATUS_CODE'
+    this.body = body
+    this.status = statusCode
+    this.statusCode = statusCode
+    this.headers = headers
+  }
+}
+
+class InvalidArgumentError extends UndiciError {
+  constructor (message) {
+    super(message)
+    Error.captureStackTrace(this, InvalidArgumentError)
+    this.name = 'InvalidArgumentError'
+    this.message = message || 'Invalid Argument Error'
+    this.code = 'UND_ERR_INVALID_ARG'
+  }
+}
+
+class InvalidReturnValueError extends UndiciError {
+  constructor (message) {
+    super(message)
+    Error.captureStackTrace(this, InvalidReturnValueError)
+    this.name = 'InvalidReturnValueError'
+    this.message = message || 'Invalid Return Value Error'
+    this.code = 'UND_ERR_INVALID_RETURN_VALUE'
+  }
+}
+
+class RequestAbortedError extends UndiciError {
+  constructor (message) {
+    super(message)
+    Error.captureStackTrace(this, RequestAbortedError)
+    this.name = 'AbortError'
+    this.message = message || 'Request aborted'
+    this.code = 'UND_ERR_ABORTED'
+  }
+}
+
+class InformationalError extends UndiciError {
+  constructor (message) {
+    super(message)
+    Error.captureStackTrace(this, InformationalError)
+    this.name = 'InformationalError'
+    this.message = message || 'Request information'
+    this.code = 'UND_ERR_INFO'
+  }
+}
+
+class RequestContentLengthMismatchError extends UndiciError {
+  constructor (message) {
+    super(message)
+    Error.captureStackTrace(this, RequestContentLengthMismatchError)
+    this.name = 'RequestContentLengthMismatchError'
+    this.message = message || 'Request body length does not match content-length header'
+    this.code = 'UND_ERR_REQ_CONTENT_LENGTH_MISMATCH'
+  }
+}
+
+class ResponseContentLengthMismatchError extends UndiciError {
+  constructor (message) {
+    super(message)
+    Error.captureStackTrace(this, ResponseContentLengthMismatchError)
+    this.name = 'ResponseContentLengthMismatchError'
+    this.message = message || 'Response body length does not match content-length header'
+    this.code = 'UND_ERR_RES_CONTENT_LENGTH_MISMATCH'
+  }
+}
+
+class ClientDestroyedError extends UndiciError {
+  constructor (message) {
+    super(message)
+    Error.captureStackTrace(this, ClientDestroyedError)
+    this.name = 'ClientDestroyedError'
+    this.message = message || 'The client is destroyed'
+    this.code = 'UND_ERR_DESTROYED'
+  }
+}
+
+class ClientClosedError extends UndiciError {
+  constructor (message) {
+    super(message)
+    Error.captureStackTrace(this, ClientClosedError)
+    this.name = 'ClientClosedError'
+    this.message = message || 'The client is closed'
+    this.code = 'UND_ERR_CLOSED'
+  }
+}
+
+class SocketError extends UndiciError {
+  constructor (message, socket) {
+    super(message)
+    Error.captureStackTrace(this, SocketError)
+    this.name = 'SocketError'
+    this.message = message || 'Socket error'
+    this.code = 'UND_ERR_SOCKET'
+    this.socket = socket
+  }
+}
+
+class NotSupportedError extends UndiciError {
+  constructor (message) {
+    super(message)
+    Error.captureStackTrace(this, NotSupportedError)
+    this.name = 'NotSupportedError'
+    this.message = message || 'Not supported error'
+    this.code = 'UND_ERR_NOT_SUPPORTED'
+  }
+}
+
+class BalancedPoolMissingUpstreamError extends UndiciError {
+  constructor (message) {
+    super(message)
+    Error.captureStackTrace(this, NotSupportedError)
+    this.name = 'MissingUpstreamError'
+    this.message = message || 'No upstream has been added to the BalancedPool'
+    this.code = 'UND_ERR_BPL_MISSING_UPSTREAM'
+  }
+}
+
+class HTTPParserError extends Error {
+  constructor (message, code, data) {
+    super(message)
+    Error.captureStackTrace(this, HTTPParserError)
+    this.name = 'HTTPParserError'
+    this.code = code ? `HPE_${code}` : undefined
+    this.data = data ? data.toString() : undefined
+  }
+}
+
+class ResponseExceededMaxSizeError extends UndiciError {
+  constructor (message) {
+    super(message)
+    Error.captureStackTrace(this, ResponseExceededMaxSizeError)
+    this.name = 'ResponseExceededMaxSizeError'
+    this.message = message || 'Response content exceeded max size'
+    this.code = 'UND_ERR_RES_EXCEEDED_MAX_SIZE'
+  }
+}
+
+class RequestRetryError extends UndiciError {
+  constructor (message, code, { headers, data }) {
+    super(message)
+    Error.captureStackTrace(this, RequestRetryError)
+    this.name = 'RequestRetryError'
+    this.message = message || 'Request retry error'
+    this.code = 'UND_ERR_REQ_RETRY'
+    this.statusCode = code
+    this.data = data
+    this.headers = headers
+  }
+}
+
+module.exports = {
+  HTTPParserError,
+  UndiciError,
+  HeadersTimeoutError,
+  HeadersOverflowError,
+  BodyTimeoutError,
+  RequestContentLengthMismatchError,
+  ConnectTimeoutError,
+  ResponseStatusCodeError,
+  InvalidArgumentError,
+  InvalidReturnValueError,
+  RequestAbortedError,
+  ClientDestroyedError,
+  ClientClosedError,
+  InformationalError,
+  SocketError,
+  NotSupportedError,
+  ResponseContentLengthMismatchError,
+  BalancedPoolMissingUpstreamError,
+  ResponseExceededMaxSizeError,
+  RequestRetryError
+}
diff --git a/lib/core/request.js b/lib/core/request.js
new file mode 100644
index 0000000..3697e6a
--- /dev/null
+++ b/lib/core/request.js
@@ -0,0 +1,499 @@
+'use strict'
+
+const {
+  InvalidArgumentError,
+  NotSupportedError
+} = require('./errors')
+const assert = require('assert')
+const { kHTTP2BuildRequest, kHTTP2CopyHeaders, kHTTP1BuildRequest } = require('./symbols')
+const util = require('./util')
+
+// tokenRegExp and headerCharRegex have been lifted from
+// https://github.com/nodejs/node/blob/main/lib/_http_common.js
+
+/**
+ * Verifies that the given val is a valid HTTP token
+ * per the rules defined in RFC 7230
+ * See https://tools.ietf.org/html/rfc7230#section-3.2.6
+ */
+const tokenRegExp = /^[\^_`a-zA-Z\-0-9!#$%&'*+.|~]+$/
+
+/**
+ * Matches if val contains an invalid field-vchar
+ *  field-value    = *( field-content / obs-fold )
+ *  field-content  = field-vchar [ 1*( SP / HTAB ) field-vchar ]
+ *  field-vchar    = VCHAR / obs-text
+ */
+const headerCharRegex = /[^\t\x20-\x7e\x80-\xff]/
+
+// Verifies that a given path is valid does not contain control chars \x00 to \x20
+const invalidPathRegex = /[^\u0021-\u00ff]/
+
+const kHandler = Symbol('handler')
+
+const channels = {}
+
+let extractBody
+
+try {
+  const diagnosticsChannel = require('diagnostics_channel')
+  channels.create = diagnosticsChannel.channel('undici:request:create')
+  channels.bodySent = diagnosticsChannel.channel('undici:request:bodySent')
+  channels.headers = diagnosticsChannel.channel('undici:request:headers')
+  channels.trailers = diagnosticsChannel.channel('undici:request:trailers')
+  channels.error = diagnosticsChannel.channel('undici:request:error')
+} catch {
+  channels.create = { hasSubscribers: false }
+  channels.bodySent = { hasSubscribers: false }
+  channels.headers = { hasSubscribers: false }
+  channels.trailers = { hasSubscribers: false }
+  channels.error = { hasSubscribers: false }
+}
+
+class Request {
+  constructor (origin, {
+    path,
+    method,
+    body,
+    headers,
+    query,
+    idempotent,
+    blocking,
+    upgrade,
+    headersTimeout,
+    bodyTimeout,
+    reset,
+    throwOnError,
+    expectContinue
+  }, handler) {
+    if (typeof path !== 'string') {
+      throw new InvalidArgumentError('path must be a string')
+    } else if (
+      path[0] !== '/' &&
+      !(path.startsWith('http://') || path.startsWith('https://')) &&
+      method !== 'CONNECT'
+    ) {
+      throw new InvalidArgumentError('path must be an absolute URL or start with a slash')
+    } else if (invalidPathRegex.exec(path) !== null) {
+      throw new InvalidArgumentError('invalid request path')
+    }
+
+    if (typeof method !== 'string') {
+      throw new InvalidArgumentError('method must be a string')
+    } else if (tokenRegExp.exec(method) === null) {
+      throw new InvalidArgumentError('invalid request method')
+    }
+
+    if (upgrade && typeof upgrade !== 'string') {
+      throw new InvalidArgumentError('upgrade must be a string')
+    }
+
+    if (headersTimeout != null && (!Number.isFinite(headersTimeout) || headersTimeout < 0)) {
+      throw new InvalidArgumentError('invalid headersTimeout')
+    }
+
+    if (bodyTimeout != null && (!Number.isFinite(bodyTimeout) || bodyTimeout < 0)) {
+      throw new InvalidArgumentError('invalid bodyTimeout')
+    }
+
+    if (reset != null && typeof reset !== 'boolean') {
+      throw new InvalidArgumentError('invalid reset')
+    }
+
+    if (expectContinue != null && typeof expectContinue !== 'boolean') {
+      throw new InvalidArgumentError('invalid expectContinue')
+    }
+
+    this.headersTimeout = headersTimeout
+
+    this.bodyTimeout = bodyTimeout
+
+    this.throwOnError = throwOnError === true
+
+    this.method = method
+
+    this.abort = null
+
+    if (body == null) {
+      this.body = null
+    } else if (util.isStream(body)) {
+      this.body = body
+
+      const rState = this.body._readableState
+      if (!rState || !rState.autoDestroy) {
+        this.endHandler = function autoDestroy () {
+          util.destroy(this)
+        }
+        this.body.on('end', this.endHandler)
+      }
+
+      this.errorHandler = err => {
+        if (this.abort) {
+          this.abort(err)
+        } else {
+          this.error = err
+        }
+      }
+      this.body.on('error', this.errorHandler)
+    } else if (util.isBuffer(body)) {
+      this.body = body.byteLength ? body : null
+    } else if (ArrayBuffer.isView(body)) {
+      this.body = body.buffer.byteLength ? Buffer.from(body.buffer, body.byteOffset, body.byteLength) : null
+    } else if (body instanceof ArrayBuffer) {
+      this.body = body.byteLength ? Buffer.from(body) : null
+    } else if (typeof body === 'string') {
+      this.body = body.length ? Buffer.from(body) : null
+    } else if (util.isFormDataLike(body) || util.isIterable(body) || util.isBlobLike(body)) {
+      this.body = body
+    } else {
+      throw new InvalidArgumentError('body must be a string, a Buffer, a Readable stream, an iterable, or an async iterable')
+    }
+
+    this.completed = false
+
+    this.aborted = false
+
+    this.upgrade = upgrade || null
+
+    this.path = query ? util.buildURL(path, query) : path
+
+    this.origin = origin
+
+    this.idempotent = idempotent == null
+      ? method === 'HEAD' || method === 'GET'
+      : idempotent
+
+    this.blocking = blocking == null ? false : blocking
+
+    this.reset = reset == null ? null : reset
+
+    this.host = null
+
+    this.contentLength = null
+
+    this.contentType = null
+
+    this.headers = ''
+
+    // Only for H2
+    this.expectContinue = expectContinue != null ? expectContinue : false
+
+    if (Array.isArray(headers)) {
+      if (headers.length % 2 !== 0) {
+        throw new InvalidArgumentError('headers array must be even')
+      }
+      for (let i = 0; i < headers.length; i += 2) {
+        processHeader(this, headers[i], headers[i + 1])
+      }
+    } else if (headers && typeof headers === 'object') {
+      const keys = Object.keys(headers)
+      for (let i = 0; i < keys.length; i++) {
+        const key = keys[i]
+        processHeader(this, key, headers[key])
+      }
+    } else if (headers != null) {
+      throw new InvalidArgumentError('headers must be an object or an array')
+    }
+
+    if (util.isFormDataLike(this.body)) {
+      if (util.nodeMajor < 16 || (util.nodeMajor === 16 && util.nodeMinor < 8)) {
+        throw new InvalidArgumentError('Form-Data bodies are only supported in node v16.8 and newer.')
+      }
+
+      if (!extractBody) {
+        extractBody = require('../fetch/body.js').extractBody
+      }
+
+      const [bodyStream, contentType] = extractBody(body)
+      if (this.contentType == null) {
+        this.contentType = contentType
+        this.headers += `content-type: ${contentType}\r\n`
+      }
+      this.body = bodyStream.stream
+      this.contentLength = bodyStream.length
+    } else if (util.isBlobLike(body) && this.contentType == null && body.type) {
+      this.contentType = body.type
+      this.headers += `content-type: ${body.type}\r\n`
+    }
+
+    util.validateHandler(handler, method, upgrade)
+
+    this.servername = util.getServerName(this.host)
+
+    this[kHandler] = handler
+
+    if (channels.create.hasSubscribers) {
+      channels.create.publish({ request: this })
+    }
+  }
+
+  onBodySent (chunk) {
+    if (this[kHandler].onBodySent) {
+      try {
+        return this[kHandler].onBodySent(chunk)
+      } catch (err) {
+        this.abort(err)
+      }
+    }
+  }
+
+  onRequestSent () {
+    if (channels.bodySent.hasSubscribers) {
+      channels.bodySent.publish({ request: this })
+    }
+
+    if (this[kHandler].onRequestSent) {
+      try {
+        return this[kHandler].onRequestSent()
+      } catch (err) {
+        this.abort(err)
+      }
+    }
+  }
+
+  onConnect (abort) {
+    assert(!this.aborted)
+    assert(!this.completed)
+
+    if (this.error) {
+      abort(this.error)
+    } else {
+      this.abort = abort
+      return this[kHandler].onConnect(abort)
+    }
+  }
+
+  onHeaders (statusCode, headers, resume, statusText) {
+    assert(!this.aborted)
+    assert(!this.completed)
+
+    if (channels.headers.hasSubscribers) {
+      channels.headers.publish({ request: this, response: { statusCode, headers, statusText } })
+    }
+
+    try {
+      return this[kHandler].onHeaders(statusCode, headers, resume, statusText)
+    } catch (err) {
+      this.abort(err)
+    }
+  }
+
+  onData (chunk) {
+    assert(!this.aborted)
+    assert(!this.completed)
+
+    try {
+      return this[kHandler].onData(chunk)
+    } catch (err) {
+      this.abort(err)
+      return false
+    }
+  }
+
+  onUpgrade (statusCode, headers, socket) {
+    assert(!this.aborted)
+    assert(!this.completed)
+
+    return this[kHandler].onUpgrade(statusCode, headers, socket)
+  }
+
+  onComplete (trailers) {
+    this.onFinally()
+
+    assert(!this.aborted)
+
+    this.completed = true
+    if (channels.trailers.hasSubscribers) {
+      channels.trailers.publish({ request: this, trailers })
+    }
+
+    try {
+      return this[kHandler].onComplete(trailers)
+    } catch (err) {
+      // TODO (fix): This might be a bad idea?
+      this.onError(err)
+    }
+  }
+
+  onError (error) {
+    this.onFinally()
+
+    if (channels.error.hasSubscribers) {
+      channels.error.publish({ request: this, error })
+    }
+
+    if (this.aborted) {
+      return
+    }
+    this.aborted = true
+
+    return this[kHandler].onError(error)
+  }
+
+  onFinally () {
+    if (this.errorHandler) {
+      this.body.off('error', this.errorHandler)
+      this.errorHandler = null
+    }
+
+    if (this.endHandler) {
+      this.body.off('end', this.endHandler)
+      this.endHandler = null
+    }
+  }
+
+  // TODO: adjust to support H2
+  addHeader (key, value) {
+    processHeader(this, key, value)
+    return this
+  }
+
+  static [kHTTP1BuildRequest] (origin, opts, handler) {
+    // TODO: Migrate header parsing here, to make Requests
+    // HTTP agnostic
+    return new Request(origin, opts, handler)
+  }
+
+  static [kHTTP2BuildRequest] (origin, opts, handler) {
+    const headers = opts.headers
+    opts = { ...opts, headers: null }
+
+    const request = new Request(origin, opts, handler)
+
+    request.headers = {}
+
+    if (Array.isArray(headers)) {
+      if (headers.length % 2 !== 0) {
+        throw new InvalidArgumentError('headers array must be even')
+      }
+      for (let i = 0; i < headers.length; i += 2) {
+        processHeader(request, headers[i], headers[i + 1], true)
+      }
+    } else if (headers && typeof headers === 'object') {
+      const keys = Object.keys(headers)
+      for (let i = 0; i < keys.length; i++) {
+        const key = keys[i]
+        processHeader(request, key, headers[key], true)
+      }
+    } else if (headers != null) {
+      throw new InvalidArgumentError('headers must be an object or an array')
+    }
+
+    return request
+  }
+
+  static [kHTTP2CopyHeaders] (raw) {
+    const rawHeaders = raw.split('\r\n')
+    const headers = {}
+
+    for (const header of rawHeaders) {
+      const [key, value] = header.split(': ')
+
+      if (value == null || value.length === 0) continue
+
+      if (headers[key]) headers[key] += `,${value}`
+      else headers[key] = value
+    }
+
+    return headers
+  }
+}
+
+function processHeaderValue (key, val, skipAppend) {
+  if (val && typeof val === 'object') {
+    throw new InvalidArgumentError(`invalid ${key} header`)
+  }
+
+  val = val != null ? `${val}` : ''
+
+  if (headerCharRegex.exec(val) !== null) {
+    throw new InvalidArgumentError(`invalid ${key} header`)
+  }
+
+  return skipAppend ? val : `${key}: ${val}\r\n`
+}
+
+function processHeader (request, key, val, skipAppend = false) {
+  if (val && (typeof val === 'object' && !Array.isArray(val))) {
+    throw new InvalidArgumentError(`invalid ${key} header`)
+  } else if (val === undefined) {
+    return
+  }
+
+  if (
+    request.host === null &&
+    key.length === 4 &&
+    key.toLowerCase() === 'host'
+  ) {
+    if (headerCharRegex.exec(val) !== null) {
+      throw new InvalidArgumentError(`invalid ${key} header`)
+    }
+    // Consumed by Client
+    request.host = val
+  } else if (
+    request.contentLength === null &&
+    key.length === 14 &&
+    key.toLowerCase() === 'content-length'
+  ) {
+    request.contentLength = parseInt(val, 10)
+    if (!Number.isFinite(request.contentLength)) {
+      throw new InvalidArgumentError('invalid content-length header')
+    }
+  } else if (
+    request.contentType === null &&
+    key.length === 12 &&
+    key.toLowerCase() === 'content-type'
+  ) {
+    request.contentType = val
+    if (skipAppend) request.headers[key] = processHeaderValue(key, val, skipAppend)
+    else request.headers += processHeaderValue(key, val)
+  } else if (
+    key.length === 17 &&
+    key.toLowerCase() === 'transfer-encoding'
+  ) {
+    throw new InvalidArgumentError('invalid transfer-encoding header')
+  } else if (
+    key.length === 10 &&
+    key.toLowerCase() === 'connection'
+  ) {
+    const value = typeof val === 'string' ? val.toLowerCase() : null
+    if (value !== 'close' && value !== 'keep-alive') {
+      throw new InvalidArgumentError('invalid connection header')
+    } else if (value === 'close') {
+      request.reset = true
+    }
+  } else if (
+    key.length === 10 &&
+    key.toLowerCase() === 'keep-alive'
+  ) {
+    throw new InvalidArgumentError('invalid keep-alive header')
+  } else if (
+    key.length === 7 &&
+    key.toLowerCase() === 'upgrade'
+  ) {
+    throw new InvalidArgumentError('invalid upgrade header')
+  } else if (
+    key.length === 6 &&
+    key.toLowerCase() === 'expect'
+  ) {
+    throw new NotSupportedError('expect header not supported')
+  } else if (tokenRegExp.exec(key) === null) {
+    throw new InvalidArgumentError('invalid header key')
+  } else {
+    if (Array.isArray(val)) {
+      for (let i = 0; i < val.length; i++) {
+        if (skipAppend) {
+          if (request.headers[key]) request.headers[key] += `,${processHeaderValue(key, val[i], skipAppend)}`
+          else request.headers[key] = processHeaderValue(key, val[i], skipAppend)
+        } else {
+          request.headers += processHeaderValue(key, val[i])
+        }
+      }
+    } else {
+      if (skipAppend) request.headers[key] = processHeaderValue(key, val, skipAppend)
+      else request.headers += processHeaderValue(key, val)
+    }
+  }
+}
+
+module.exports = Request
diff --git a/lib/core/symbols.js b/lib/core/symbols.js
new file mode 100644
index 0000000..68d8566
--- /dev/null
+++ b/lib/core/symbols.js
@@ -0,0 +1,63 @@
+module.exports = {
+  kClose: Symbol('close'),
+  kDestroy: Symbol('destroy'),
+  kDispatch: Symbol('dispatch'),
+  kUrl: Symbol('url'),
+  kWriting: Symbol('writing'),
+  kResuming: Symbol('resuming'),
+  kQueue: Symbol('queue'),
+  kConnect: Symbol('connect'),
+  kConnecting: Symbol('connecting'),
+  kHeadersList: Symbol('headers list'),
+  kKeepAliveDefaultTimeout: Symbol('default keep alive timeout'),
+  kKeepAliveMaxTimeout: Symbol('max keep alive timeout'),
+  kKeepAliveTimeoutThreshold: Symbol('keep alive timeout threshold'),
+  kKeepAliveTimeoutValue: Symbol('keep alive timeout'),
+  kKeepAlive: Symbol('keep alive'),
+  kHeadersTimeout: Symbol('headers timeout'),
+  kBodyTimeout: Symbol('body timeout'),
+  kServerName: Symbol('server name'),
+  kLocalAddress: Symbol('local address'),
+  kHost: Symbol('host'),
+  kNoRef: Symbol('no ref'),
+  kBodyUsed: Symbol('used'),
+  kRunning: Symbol('running'),
+  kBlocking: Symbol('blocking'),
+  kPending: Symbol('pending'),
+  kSize: Symbol('size'),
+  kBusy: Symbol('busy'),
+  kQueued: Symbol('queued'),
+  kFree: Symbol('free'),
+  kConnected: Symbol('connected'),
+  kClosed: Symbol('closed'),
+  kNeedDrain: Symbol('need drain'),
+  kReset: Symbol('reset'),
+  kDestroyed: Symbol.for('nodejs.stream.destroyed'),
+  kMaxHeadersSize: Symbol('max headers size'),
+  kRunningIdx: Symbol('running index'),
+  kPendingIdx: Symbol('pending index'),
+  kError: Symbol('error'),
+  kClients: Symbol('clients'),
+  kClient: Symbol('client'),
+  kParser: Symbol('parser'),
+  kOnDestroyed: Symbol('destroy callbacks'),
+  kPipelining: Symbol('pipelining'),
+  kSocket: Symbol('socket'),
+  kHostHeader: Symbol('host header'),
+  kConnector: Symbol('connector'),
+  kStrictContentLength: Symbol('strict content length'),
+  kMaxRedirections: Symbol('maxRedirections'),
+  kMaxRequests: Symbol('maxRequestsPerClient'),
+  kProxy: Symbol('proxy agent options'),
+  kCounter: Symbol('socket request counter'),
+  kInterceptors: Symbol('dispatch interceptors'),
+  kMaxResponseSize: Symbol('max response size'),
+  kHTTP2Session: Symbol('http2Session'),
+  kHTTP2SessionState: Symbol('http2Session state'),
+  kHTTP2BuildRequest: Symbol('http2 build request'),
+  kHTTP1BuildRequest: Symbol('http1 build request'),
+  kHTTP2CopyHeaders: Symbol('http2 copy headers'),
+  kHTTPConnVersion: Symbol('http connection version'),
+  kRetryHandlerDefaultRetry: Symbol('retry agent default retry'),
+  kConstruct: Symbol('constructable')
+}
diff --git a/lib/core/util.js b/lib/core/util.js
new file mode 100644
index 0000000..8d5450b
--- /dev/null
+++ b/lib/core/util.js
@@ -0,0 +1,511 @@
+'use strict'
+
+const assert = require('assert')
+const { kDestroyed, kBodyUsed } = require('./symbols')
+const { IncomingMessage } = require('http')
+const stream = require('stream')
+const net = require('net')
+const { InvalidArgumentError } = require('./errors')
+const { Blob } = require('buffer')
+const nodeUtil = require('util')
+const { stringify } = require('querystring')
+
+const [nodeMajor, nodeMinor] = process.versions.node.split('.').map(v => Number(v))
+
+function nop () {}
+
+function isStream (obj) {
+  return obj && typeof obj === 'object' && typeof obj.pipe === 'function' && typeof obj.on === 'function'
+}
+
+// based on https://github.com/node-fetch/fetch-blob/blob/8ab587d34080de94140b54f07168451e7d0b655e/index.js#L229-L241 (MIT License)
+function isBlobLike (object) {
+  return (Blob && object instanceof Blob) || (
+    object &&
+    typeof object === 'object' &&
+    (typeof object.stream === 'function' ||
+      typeof object.arrayBuffer === 'function') &&
+    /^(Blob|File)$/.test(object[Symbol.toStringTag])
+  )
+}
+
+function buildURL (url, queryParams) {
+  if (url.includes('?') || url.includes('#')) {
+    throw new Error('Query params cannot be passed when url already contains "?" or "#".')
+  }
+
+  const stringified = stringify(queryParams)
+
+  if (stringified) {
+    url += '?' + stringified
+  }
+
+  return url
+}
+
+function parseURL (url) {
+  if (typeof url === 'string') {
+    url = new URL(url)
+
+    if (!/^https?:/.test(url.origin || url.protocol)) {
+      throw new InvalidArgumentError('Invalid URL protocol: the URL must start with `http:` or `https:`.')
+    }
+
+    return url
+  }
+
+  if (!url || typeof url !== 'object') {
+    throw new InvalidArgumentError('Invalid URL: The URL argument must be a non-null object.')
+  }
+
+  if (!/^https?:/.test(url.origin || url.protocol)) {
+    throw new InvalidArgumentError('Invalid URL protocol: the URL must start with `http:` or `https:`.')
+  }
+
+  if (!(url instanceof URL)) {
+    if (url.port != null && url.port !== '' && !Number.isFinite(parseInt(url.port))) {
+      throw new InvalidArgumentError('Invalid URL: port must be a valid integer or a string representation of an integer.')
+    }
+
+    if (url.path != null && typeof url.path !== 'string') {
+      throw new InvalidArgumentError('Invalid URL path: the path must be a string or null/undefined.')
+    }
+
+    if (url.pathname != null && typeof url.pathname !== 'string') {
+      throw new InvalidArgumentError('Invalid URL pathname: the pathname must be a string or null/undefined.')
+    }
+
+    if (url.hostname != null && typeof url.hostname !== 'string') {
+      throw new InvalidArgumentError('Invalid URL hostname: the hostname must be a string or null/undefined.')
+    }
+
+    if (url.origin != null && typeof url.origin !== 'string') {
+      throw new InvalidArgumentError('Invalid URL origin: the origin must be a string or null/undefined.')
+    }
+
+    const port = url.port != null
+      ? url.port
+      : (url.protocol === 'https:' ? 443 : 80)
+    let origin = url.origin != null
+      ? url.origin
+      : `${url.protocol}//${url.hostname}:${port}`
+    let path = url.path != null
+      ? url.path
+      : `${url.pathname || ''}${url.search || ''}`
+
+    if (origin.endsWith('/')) {
+      origin = origin.substring(0, origin.length - 1)
+    }
+
+    if (path && !path.startsWith('/')) {
+      path = `/${path}`
+    }
+    // new URL(path, origin) is unsafe when `path` contains an absolute URL
+    // From https://developer.mozilla.org/en-US/docs/Web/API/URL/URL:
+    // If first parameter is a relative URL, second param is required, and will be used as the base URL.
+    // If first parameter is an absolute URL, a given second param will be ignored.
+    url = new URL(origin + path)
+  }
+
+  return url
+}
+
+function parseOrigin (url) {
+  url = parseURL(url)
+
+  if (url.pathname !== '/' || url.search || url.hash) {
+    throw new InvalidArgumentError('invalid url')
+  }
+
+  return url
+}
+
+function getHostname (host) {
+  if (host[0] === '[') {
+    const idx = host.indexOf(']')
+
+    assert(idx !== -1)
+    return host.substring(1, idx)
+  }
+
+  const idx = host.indexOf(':')
+  if (idx === -1) return host
+
+  return host.substring(0, idx)
+}
+
+// IP addresses are not valid server names per RFC6066
+// > Currently, the only server names supported are DNS hostnames
+function getServerName (host) {
+  if (!host) {
+    return null
+  }
+
+  assert.strictEqual(typeof host, 'string')
+
+  const servername = getHostname(host)
+  if (net.isIP(servername)) {
+    return ''
+  }
+
+  return servername
+}
+
+function deepClone (obj) {
+  return JSON.parse(JSON.stringify(obj))
+}
+
+function isAsyncIterable (obj) {
+  return !!(obj != null && typeof obj[Symbol.asyncIterator] === 'function')
+}
+
+function isIterable (obj) {
+  return !!(obj != null && (typeof obj[Symbol.iterator] === 'function' || typeof obj[Symbol.asyncIterator] === 'function'))
+}
+
+function bodyLength (body) {
+  if (body == null) {
+    return 0
+  } else if (isStream(body)) {
+    const state = body._readableState
+    return state && state.objectMode === false && state.ended === true && Number.isFinite(state.length)
+      ? state.length
+      : null
+  } else if (isBlobLike(body)) {
+    return body.size != null ? body.size : null
+  } else if (isBuffer(body)) {
+    return body.byteLength
+  }
+
+  return null
+}
+
+function isDestroyed (stream) {
+  return !stream || !!(stream.destroyed || stream[kDestroyed])
+}
+
+function isReadableAborted (stream) {
+  const state = stream && stream._readableState
+  return isDestroyed(stream) && state && !state.endEmitted
+}
+
+function destroy (stream, err) {
+  if (stream == null || !isStream(stream) || isDestroyed(stream)) {
+    return
+  }
+
+  if (typeof stream.destroy === 'function') {
+    if (Object.getPrototypeOf(stream).constructor === IncomingMessage) {
+      // See: https://github.com/nodejs/node/pull/38505/files
+      stream.socket = null
+    }
+
+    stream.destroy(err)
+  } else if (err) {
+    process.nextTick((stream, err) => {
+      stream.emit('error', err)
+    }, stream, err)
+  }
+
+  if (stream.destroyed !== true) {
+    stream[kDestroyed] = true
+  }
+}
+
+const KEEPALIVE_TIMEOUT_EXPR = /timeout=(\d+)/
+function parseKeepAliveTimeout (val) {
+  const m = val.toString().match(KEEPALIVE_TIMEOUT_EXPR)
+  return m ? parseInt(m[1], 10) * 1000 : null
+}
+
+function parseHeaders (headers, obj = {}) {
+  // For H2 support
+  if (!Array.isArray(headers)) return headers
+
+  for (let i = 0; i < headers.length; i += 2) {
+    const key = headers[i].toString().toLowerCase()
+    let val = obj[key]
+
+    if (!val) {
+      if (Array.isArray(headers[i + 1])) {
+        obj[key] = headers[i + 1].map(x => x.toString('utf8'))
+      } else {
+        obj[key] = headers[i + 1].toString('utf8')
+      }
+    } else {
+      if (!Array.isArray(val)) {
+        val = [val]
+        obj[key] = val
+      }
+      val.push(headers[i + 1].toString('utf8'))
+    }
+  }
+
+  // See https://github.com/nodejs/node/pull/46528
+  if ('content-length' in obj && 'content-disposition' in obj) {
+    obj['content-disposition'] = Buffer.from(obj['content-disposition']).toString('latin1')
+  }
+
+  return obj
+}
+
+function parseRawHeaders (headers) {
+  const ret = []
+  let hasContentLength = false
+  let contentDispositionIdx = -1
+
+  for (let n = 0; n < headers.length; n += 2) {
+    const key = headers[n + 0].toString()
+    const val = headers[n + 1].toString('utf8')
+
+    if (key.length === 14 && (key === 'content-length' || key.toLowerCase() === 'content-length')) {
+      ret.push(key, val)
+      hasContentLength = true
+    } else if (key.length === 19 && (key === 'content-disposition' || key.toLowerCase() === 'content-disposition')) {
+      contentDispositionIdx = ret.push(key, val) - 1
+    } else {
+      ret.push(key, val)
+    }
+  }
+
+  // See https://github.com/nodejs/node/pull/46528
+  if (hasContentLength && contentDispositionIdx !== -1) {
+    ret[contentDispositionIdx] = Buffer.from(ret[contentDispositionIdx]).toString('latin1')
+  }
+
+  return ret
+}
+
+function isBuffer (buffer) {
+  // See, https://github.com/mcollina/undici/pull/319
+  return buffer instanceof Uint8Array || Buffer.isBuffer(buffer)
+}
+
+function validateHandler (handler, method, upgrade) {
+  if (!handler || typeof handler !== 'object') {
+    throw new InvalidArgumentError('handler must be an object')
+  }
+
+  if (typeof handler.onConnect !== 'function') {
+    throw new InvalidArgumentError('invalid onConnect method')
+  }
+
+  if (typeof handler.onError !== 'function') {
+    throw new InvalidArgumentError('invalid onError method')
+  }
+
+  if (typeof handler.onBodySent !== 'function' && handler.onBodySent !== undefined) {
+    throw new InvalidArgumentError('invalid onBodySent method')
+  }
+
+  if (upgrade || method === 'CONNECT') {
+    if (typeof handler.onUpgrade !== 'function') {
+      throw new InvalidArgumentError('invalid onUpgrade method')
+    }
+  } else {
+    if (typeof handler.onHeaders !== 'function') {
+      throw new InvalidArgumentError('invalid onHeaders method')
+    }
+
+    if (typeof handler.onData !== 'function') {
+      throw new InvalidArgumentError('invalid onData method')
+    }
+
+    if (typeof handler.onComplete !== 'function') {
+      throw new InvalidArgumentError('invalid onComplete method')
+    }
+  }
+}
+
+// A body is disturbed if it has been read from and it cannot
+// be re-used without losing state or data.
+function isDisturbed (body) {
+  return !!(body && (
+    stream.isDisturbed
+      ? stream.isDisturbed(body) || body[kBodyUsed] // TODO (fix): Why is body[kBodyUsed] needed?
+      : body[kBodyUsed] ||
+        body.readableDidRead ||
+        (body._readableState && body._readableState.dataEmitted) ||
+        isReadableAborted(body)
+  ))
+}
+
+function isErrored (body) {
+  return !!(body && (
+    stream.isErrored
+      ? stream.isErrored(body)
+      : /state: 'errored'/.test(nodeUtil.inspect(body)
+      )))
+}
+
+function isReadable (body) {
+  return !!(body && (
+    stream.isReadable
+      ? stream.isReadable(body)
+      : /state: 'readable'/.test(nodeUtil.inspect(body)
+      )))
+}
+
+function getSocketInfo (socket) {
+  return {
+    localAddress: socket.localAddress,
+    localPort: socket.localPort,
+    remoteAddress: socket.remoteAddress,
+    remotePort: socket.remotePort,
+    remoteFamily: socket.remoteFamily,
+    timeout: socket.timeout,
+    bytesWritten: socket.bytesWritten,
+    bytesRead: socket.bytesRead
+  }
+}
+
+async function * convertIterableToBuffer (iterable) {
+  for await (const chunk of iterable) {
+    yield Buffer.isBuffer(chunk) ? chunk : Buffer.from(chunk)
+  }
+}
+
+let ReadableStream
+function ReadableStreamFrom (iterable) {
+  if (!ReadableStream) {
+    ReadableStream = require('stream/web').ReadableStream
+  }
+
+  if (ReadableStream.from) {
+    return ReadableStream.from(convertIterableToBuffer(iterable))
+  }
+
+  let iterator
+  return new ReadableStream(
+    {
+      async start () {
+        iterator = iterable[Symbol.asyncIterator]()
+      },
+      async pull (controller) {
+        const { done, value } = await iterator.next()
+        if (done) {
+          queueMicrotask(() => {
+            controller.close()
+          })
+        } else {
+          const buf = Buffer.isBuffer(value) ? value : Buffer.from(value)
+          controller.enqueue(new Uint8Array(buf))
+        }
+        return controller.desiredSize > 0
+      },
+      async cancel (reason) {
+        await iterator.return()
+      }
+    },
+    0
+  )
+}
+
+// The chunk should be a FormData instance and contains
+// all the required methods.
+function isFormDataLike (object) {
+  return (
+    object &&
+    typeof object === 'object' &&
+    typeof object.append === 'function' &&
+    typeof object.delete === 'function' &&
+    typeof object.get === 'function' &&
+    typeof object.getAll === 'function' &&
+    typeof object.has === 'function' &&
+    typeof object.set === 'function' &&
+    object[Symbol.toStringTag] === 'FormData'
+  )
+}
+
+function throwIfAborted (signal) {
+  if (!signal) { return }
+  if (typeof signal.throwIfAborted === 'function') {
+    signal.throwIfAborted()
+  } else {
+    if (signal.aborted) {
+      // DOMException not available < v17.0.0
+      const err = new Error('The operation was aborted')
+      err.name = 'AbortError'
+      throw err
+    }
+  }
+}
+
+function addAbortListener (signal, listener) {
+  if ('addEventListener' in signal) {
+    signal.addEventListener('abort', listener, { once: true })
+    return () => signal.removeEventListener('abort', listener)
+  }
+  signal.addListener('abort', listener)
+  return () => signal.removeListener('abort', listener)
+}
+
+const hasToWellFormed = !!String.prototype.toWellFormed
+
+/**
+ * @param {string} val
+ */
+function toUSVString (val) {
+  if (hasToWellFormed) {
+    return `${val}`.toWellFormed()
+  } else if (nodeUtil.toUSVString) {
+    return nodeUtil.toUSVString(val)
+  }
+
+  return `${val}`
+}
+
+// Parsed accordingly to RFC 9110
+// https://www.rfc-editor.org/rfc/rfc9110#field.content-range
+function parseRangeHeader (range) {
+  if (range == null || range === '') return { start: 0, end: null, size: null }
+
+  const m = range ? range.match(/^bytes (\d+)-(\d+)\/(\d+)?$/) : null
+  return m
+    ? {
+        start: parseInt(m[1]),
+        end: m[2] ? parseInt(m[2]) : null,
+        size: m[3] ? parseInt(m[3]) : null
+      }
+    : null
+}
+
+const kEnumerableProperty = Object.create(null)
+kEnumerableProperty.enumerable = true
+
+module.exports = {
+  kEnumerableProperty,
+  nop,
+  isDisturbed,
+  isErrored,
+  isReadable,
+  toUSVString,
+  isReadableAborted,
+  isBlobLike,
+  parseOrigin,
+  parseURL,
+  getServerName,
+  isStream,
+  isIterable,
+  isAsyncIterable,
+  isDestroyed,
+  parseRawHeaders,
+  parseHeaders,
+  parseKeepAliveTimeout,
+  destroy,
+  bodyLength,
+  deepClone,
+  ReadableStreamFrom,
+  isBuffer,
+  validateHandler,
+  getSocketInfo,
+  isFormDataLike,
+  buildURL,
+  throwIfAborted,
+  addAbortListener,
+  parseRangeHeader,
+  nodeMajor,
+  nodeMinor,
+  nodeHasAutoSelectFamily: nodeMajor > 18 || (nodeMajor === 18 && nodeMinor >= 13),
+  safeHTTPMethods: ['GET', 'HEAD', 'OPTIONS', 'TRACE']
+}