third_party/WebKit/Source/modules/fetch/Headers.cpp

// Copyright 2014 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "modules/fetch/Headers.h"

#include "bindings/core/v8/Dictionary.h"
#include "bindings/core/v8/ExceptionState.h"
#include "bindings/core/v8/V8IteratorResultValue.h"
#include "core/dom/Iterator.h"
#include "core/fetch/FetchUtils.h"
#include "wtf/NotFound.h"
#include "wtf/PassRefPtr.h"
#include "wtf/RefPtr.h"
#include "wtf/text/WTFString.h"

namespace blink {

namespace {

class HeadersIterationSource final
    : public PairIterable<String, String>::IterationSource {
 public:
  explicit HeadersIterationSource(const FetchHeaderList* headers)
      : m_headers(headers->clone()), m_current(0) {
    m_headers->sortAndCombine();
  }

  bool next(ScriptState* scriptState,
            String& key,
            String& value,
            ExceptionState& exception) override {
    // This simply advances an index and returns the next value if any; the
    // iterated list is not exposed to script so it will never be mutated
    // during iteration.
    if (m_current >= m_headers->size())
      return false;

    const FetchHeaderList::Header& header = m_headers->entry(m_current++);
    key = header.first;
    value = header.second;
    return true;
  }

  DEFINE_INLINE_VIRTUAL_TRACE() {
    visitor->trace(m_headers);
    PairIterable<String, String>::IterationSource::trace(visitor);
  }

 private:
  const Member<FetchHeaderList> m_headers;
  size_t m_current;
};

}  // namespace

Headers* Headers::create() {
  return new Headers;
}

Headers* Headers::create(ExceptionState&) {
  return create();
}

Headers* Headers::create(const Headers* init, ExceptionState& exceptionState) {
  // "The Headers(|init|) constructor, when invoked, must run these steps:"
  // "1. Let |headers| be a new Headers object."
  Headers* headers = create();
  // "2. If |init| is given, fill headers with |init|. Rethrow any exception."
  headers->fillWith(init, exceptionState);
  // "3. Return |headers|."
  return headers;
}

Headers* Headers::create(const Vector<Vector<String>>& init,
                         ExceptionState& exceptionState) {
  // The same steps as above.
  Headers* headers = create();
  headers->fillWith(init, exceptionState);
  return headers;
}

Headers* Headers::create(const Dictionary& init,
                         ExceptionState& exceptionState) {
  // "The Headers(|init|) constructor, when invoked, must run these steps:"
  // "1. Let |headers| be a new Headers object."
  Headers* headers = create();
  // "2. If |init| is given, fill headers with |init|. Rethrow any exception."
  headers->fillWith(init, exceptionState);
  // "3. Return |headers|."
  return headers;
}

Headers* Headers::create(FetchHeaderList* headerList) {
  return new Headers(headerList);
}

Headers* Headers::clone() const {
  FetchHeaderList* headerList = m_headerList->clone();
  Headers* headers = create(headerList);
  headers->m_guard = m_guard;
  return headers;
}

void Headers::append(const String& name,
                     const String& value,
                     ExceptionState& exceptionState) {
  // "To append a name/value (|name|/|value|) pair to a Headers object
  // (|headers|), run these steps:"
  // "1. If |name| is not a name or |value| is not a value, throw a
  //     TypeError."
  if (!FetchHeaderList::isValidHeaderName(name)) {
    exceptionState.throwTypeError("Invalid name");
    return;
  }
  if (!FetchHeaderList::isValidHeaderValue(value)) {
    exceptionState.throwTypeError("Invalid value");
    return;
  }
  // "2. If guard is |request|, throw a TypeError."
  if (m_guard == ImmutableGuard) {
    exceptionState.throwTypeError("Headers are immutable");
    return;
  }
  // "3. Otherwise, if guard is |request| and |name| is a forbidden header
  //     name, return."
  if (m_guard == RequestGuard && FetchUtils::isForbiddenHeaderName(name))
    return;
  // "4. Otherwise, if guard is |request-no-CORS| and |name|/|value| is not a
  //     simple header, return."
  if (m_guard == RequestNoCORSGuard &&
      !FetchUtils::isSimpleHeader(AtomicString(name), AtomicString(value)))
    return;
  // "5. Otherwise, if guard is |response| and |name| is a forbidden response
  //     header name, return."
  if (m_guard == ResponseGuard &&
      FetchUtils::isForbiddenResponseHeaderName(name))
    return;
  // "6. Append |name|/|value| to header list."
  m_headerList->append(name, value);
}

void Headers::remove(const String& name, ExceptionState& exceptionState) {
  // "The delete(|name|) method, when invoked, must run these steps:"
  // "1. If name is not a name, throw a TypeError."
  if (!FetchHeaderList::isValidHeaderName(name)) {
    exceptionState.throwTypeError("Invalid name");
    return;
  }
  // "2. If guard is |immutable|, throw a TypeError."
  if (m_guard == ImmutableGuard) {
    exceptionState.throwTypeError("Headers are immutable");
    return;
  }
  // "3. Otherwise, if guard is |request| and |name| is a forbidden header
  //     name, return."
  if (m_guard == RequestGuard && FetchUtils::isForbiddenHeaderName(name))
    return;
  // "4. Otherwise, if guard is |request-no-CORS| and |name|/`invalid` is not
  //     a simple header, return."
  if (m_guard == RequestNoCORSGuard &&
      !FetchUtils::isSimpleHeader(AtomicString(name), "invalid"))
    return;
  // "5. Otherwise, if guard is |response| and |name| is a forbidden response
  //     header name, return."
  if (m_guard == ResponseGuard &&
      FetchUtils::isForbiddenResponseHeaderName(name))
    return;
  // "6. Delete |name| from header list."
  m_headerList->remove(name);
}

String Headers::get(const String& name, ExceptionState& exceptionState) {
  // "The get(|name|) method, when invoked, must run these steps:"
  // "1. If |name| is not a name, throw a TypeError."
  if (!FetchHeaderList::isValidHeaderName(name)) {
    exceptionState.throwTypeError("Invalid name");
    return String();
  }
  // "2. If there is no header in header list whose name is |name|,
  //     return null."
  // "3. Return the combined value given |name| and header list."
  String result;
  m_headerList->get(name, result);
  return result;
}

Vector<String> Headers::getAll(const String& name,
                               ExceptionState& exceptionState) {
  // "The getAll(|name|) method, when invoked, must run these steps:"
  // "1. If |name| is not a name, throw a TypeError."
  if (!FetchHeaderList::isValidHeaderName(name)) {
    exceptionState.throwTypeError("Invalid name");
    return Vector<String>();
  }
  // "2. Return the values of all headers in header list whose name is |name|,
  //     in list order, and the empty sequence otherwise."
  Vector<String> result;
  m_headerList->getAll(name, result);
  return result;
}

bool Headers::has(const String& name, ExceptionState& exceptionState) {
  // "The has(|name|) method, when invoked, must run these steps:"
  // "1. If |name| is not a name, throw a TypeError."
  if (!FetchHeaderList::isValidHeaderName(name)) {
    exceptionState.throwTypeError("Invalid name");
    return false;
  }
  // "2. Return true if there is a header in header list whose name is |name|,
  //     and false otherwise."
  return m_headerList->has(name);
}

void Headers::set(const String& name,
                  const String& value,
                  ExceptionState& exceptionState) {
  // "The set(|name|, |value|) method, when invoked, must run these steps:"
  // "1. If |name| is not a name or |value| is not a value, throw a
  //     TypeError."
  if (!FetchHeaderList::isValidHeaderName(name)) {
    exceptionState.throwTypeError("Invalid name");
    return;
  }
  if (!FetchHeaderList::isValidHeaderValue(value)) {
    exceptionState.throwTypeError("Invalid value");
    return;
  }
  // "2. If guard is |immutable|, throw a TypeError."
  if (m_guard == ImmutableGuard) {
    exceptionState.throwTypeError("Headers are immutable");
    return;
  }
  // "3. Otherwise, if guard is |request| and |name| is a forbidden header
  //     name, return."
  if (m_guard == RequestGuard && FetchUtils::isForbiddenHeaderName(name))
    return;
  // "4. Otherwise, if guard is |request-no-CORS| and |name|/|value| is not a
  //     simple header, return."
  if (m_guard == RequestNoCORSGuard &&
      !FetchUtils::isSimpleHeader(AtomicString(name), AtomicString(value)))
    return;
  // "5. Otherwise, if guard is |response| and |name| is a forbidden response
  //     header name, return."
  if (m_guard == ResponseGuard &&
      FetchUtils::isForbiddenResponseHeaderName(name))
    return;
  // "6. Set |name|/|value| in header list."
  m_headerList->set(name, value);
}

void Headers::fillWith(const Headers* object, ExceptionState& exceptionState) {
  ASSERT(m_headerList->size() == 0);
  // "To fill a Headers object (|this|) with a given object (|object|), run
  // these steps:"
  // "1. If |object| is a Headers object, copy its header list as
  //     |headerListCopy| and then for each |header| in |headerListCopy|,
  //     retaining order, append header's |name|/|header|'s value to
  //     |headers|. Rethrow any exception."
  for (size_t i = 0; i < object->m_headerList->list().size(); ++i) {
    append(object->m_headerList->list()[i]->first,
           object->m_headerList->list()[i]->second, exceptionState);
    if (exceptionState.hadException())
      return;
  }
}

void Headers::fillWith(const Vector<Vector<String>>& object,
                       ExceptionState& exceptionState) {
  ASSERT(!m_headerList->size());
  // "2. Otherwise, if |object| is a sequence, then for each |header| in
  //     |object|, run these substeps:
  //    1. If |header| does not contain exactly two items, throw a
  //       TypeError.
  //    2. Append |header|'s first item/|header|'s second item to
  //       |headers|. Rethrow any exception."
  for (size_t i = 0; i < object.size(); ++i) {
    if (object[i].size() != 2) {
      exceptionState.throwTypeError("Invalid value");
      return;
    }
    append(object[i][0], object[i][1], exceptionState);
    if (exceptionState.hadException())
      return;
  }
}

void Headers::fillWith(const Dictionary& object,
                       ExceptionState& exceptionState) {
  ASSERT(!m_headerList->size());
  const Vector<String>& keys = object.getPropertyNames(exceptionState);
  if (exceptionState.hadException() || !keys.size())
    return;

  // "3. Otherwise, if |object| is an open-ended dictionary, then for each
  //    |header| in object, run these substeps:
  //    1. Set |header|'s key to |header|'s key, converted to ByteString.
  //       Rethrow any exception.
  //    2. Append |header|'s key/|header|'s value to |headers|. Rethrow any
  //       exception."
  // FIXME: Support OpenEndedDictionary<ByteString>.
  for (size_t i = 0; i < keys.size(); ++i) {
    String value;
    if (!DictionaryHelper::get(object, keys[i], value)) {
      exceptionState.throwTypeError("Invalid value");
      return;
    }
    append(keys[i], value, exceptionState);
    if (exceptionState.hadException())
      return;
  }
}

Headers::Headers()
    : m_headerList(FetchHeaderList::create()), m_guard(NoneGuard) {}

Headers::Headers(FetchHeaderList* headerList)
    : m_headerList(headerList), m_guard(NoneGuard) {}

DEFINE_TRACE(Headers) {
  visitor->trace(m_headerList);
}

PairIterable<String, String>::IterationSource* Headers::startIteration(
    ScriptState*,
    ExceptionState&) {
  return new HeadersIterationSource(m_headerList);
}

}  // namespace blink