```
#### `QueryDict.__getitem__(key)`
Returns the value for the given key. If the key has more than one value,
it returns the last value. Raises
`django.utils.datastructures.MultiValueDictKeyError` if the key does not
exist. (This is a subclass of Python's standard [`KeyError`](https://docs.python.org/3/library/exceptions.html#KeyError), so you can
stick to catching `KeyError`.)
#### `QueryDict.__setitem__(key, value)`
Sets the given key to `[value]` (a list whose single element is
`value`). Note that this, as other dictionary functions that have side
effects, can only be called on a mutable `QueryDict` (such as one that
was created via [`QueryDict.copy()`](#django.http.QueryDict.copy)).
#### `QueryDict.__contains__(key)`
Returns `True` if the given key is set. This lets you do, e.g., `if "foo"
in request.GET`.
#### `QueryDict.get(key, default=None)`
Uses the same logic as [`__getitem__()`](#django.http.QueryDict.__getitem__), with a hook for returning a
default value if the key doesn't exist.
#### `QueryDict.setdefault(key, default=None)`
Like [`dict.setdefault()`](https://docs.python.org/3/library/stdtypes.html#dict.setdefault), except it uses [`__setitem__()`](#django.http.QueryDict.__setitem__) internally.
#### `QueryDict.update(other_dict)`
Takes either a `QueryDict` or a dictionary. Like [`dict.update()`](https://docs.python.org/3/library/stdtypes.html#dict.update),
except it *appends* to the current dictionary items rather than replacing
them. For example:
```
>>> q = QueryDict('a=1', mutable=True)
>>> q.update({'a': '2'})
>>> q.getlist('a')
['1', '2']
>>> q['a'] # returns the last
'2'
```
#### `QueryDict.items()`
Like [`dict.items()`](https://docs.python.org/3/library/stdtypes.html#dict.items), except this uses the same last-value logic as
[`__getitem__()`](#django.http.QueryDict.__getitem__). For example:
```
>>> q = QueryDict('a=1&a=2&a=3')
>>> q.items()
[('a', '3')]
```
#### `QueryDict.iteritems()`
Like `dict.iteritems()`, except this uses the same last-value logic as
[`__getitem__()`](#django.http.QueryDict.__getitem__).
Python 2 のみで使えます。
#### `QueryDict.iterlists()`
Like [`QueryDict.iteritems()`](#django.http.QueryDict.iteritems) except it includes all values, as a list,
for each member of the dictionary.
Python 2 のみで使えます。
#### `QueryDict.values()`
Like [`dict.values()`](https://docs.python.org/3/library/stdtypes.html#dict.values), except this uses the same last-value logic as
[`__getitem__()`](#django.http.QueryDict.__getitem__). For example:
```
>>> q = QueryDict('a=1&a=2&a=3')
>>> q.values()
['3']
```
#### `QueryDict.itervalues()`
Just like [`QueryDict.values()`](#django.http.QueryDict.values), except an iterator.
Python 2 のみで使えます。
In addition, `QueryDict` has the following methods:
#### `QueryDict.copy()`
Returns a copy of the object using [`copy.deepcopy()`](https://docs.python.org/3/library/copy.html#copy.deepcopy). This copy will
be mutable even if the original was not.
#### `QueryDict.getlist(key, default=None)`
Returns a list of the data with the requested key. Returns an empty list if
the key doesn't exist and a default value wasn't provided. It's guaranteed
to return a list unless the default value provided isn't a list.
#### `QueryDict.setlist(key, list_)`
Sets the given key to `list_` (unlike [`__setitem__()`](#django.http.QueryDict.__setitem__)).
#### `QueryDict.appendlist(key, item)`
Appends an item to the internal list associated with key.
#### `QueryDict.setlistdefault(key, default_list=None)`
Like [`setdefault()`](#django.http.QueryDict.setdefault), except it takes a list of values instead of a
single value.
#### `QueryDict.lists()`
Like [`items()`](#django.http.QueryDict.items), except it includes all values, as a list, for each
member of the dictionary. For example:
```
>>> q = QueryDict('a=1&a=2&a=3')
>>> q.lists()
[('a', ['1', '2', '3'])]
```
#### `QueryDict.pop(key)`
Returns a list of values for the given key and removes them from the
dictionary. Raises `KeyError` if the key does not exist. For example:
```
>>> q = QueryDict('a=1&a=2&a=3', mutable=True)
>>> q.pop('a')
['1', '2', '3']
```
#### `QueryDict.popitem()`
Removes an arbitrary member of the dictionary (since there's no concept
of ordering), and returns a two value tuple containing the key and a list
of all values for the key. Raises `KeyError` when called on an empty
dictionary. For example:
```
>>> q = QueryDict('a=1&a=2&a=3', mutable=True)
>>> q.popitem()
('a', ['1', '2', '3'])
```
#### `QueryDict.dict()`
Returns a `dict` representation of `QueryDict`. For every (key, list)
pair in `QueryDict`, `dict` will have (key, item), where item is one
element of the list, using the same logic as [`QueryDict.__getitem__()`](#django.http.QueryDict.__getitem__):
```
>>> q = QueryDict('a=1&a=3&a=5')
>>> q.dict()
{'a': '5'}
```
#### `QueryDict.urlencode(safe=None)`
Returns a string of the data in query string format. For example:
```
>>> q = QueryDict('a=2&b=3&b=5')
>>> q.urlencode()
'a=2&b=3&b=5'
```
Use the `safe` parameter to pass characters which don't require encoding.
For example:
```
>>> q = QueryDict(mutable=True)
>>> q['next'] = '/a&b/'
>>> q.urlencode(safe='/')
'next=/a%26b/'
```
## `HttpResponse` オブジェクト
#### `class HttpResponse`
In contrast to [`HttpRequest`](#django.http.HttpRequest) objects, which are created automatically by
Django, [`HttpResponse`](#django.http.HttpResponse) objects are your responsibility. Each view you
write is responsible for instantiating, populating, and returning an
[`HttpResponse`](#django.http.HttpResponse).
[`HttpResponse`](#django.http.HttpResponse) クラスは [`django.http`](#module-django.http) モジュール内に存在します。
### 使い方
#### 文字列を引き渡す
一般的な使い方は、[`HttpResponse`](#django.http.HttpResponse) コンストラクタに、文字列として、ページの内容を引き渡すことです:
```
>>> from django.http import HttpResponse
>>> response = HttpResponse("Here's the text of the Web page.")
>>> response = HttpResponse("Text only, please.", content_type="text/plain")
```
内容を段階的に追加したい場合は、`response` をファイルライクなオブジェクトとして使うことができます:
```
>>> response = HttpResponse()
>>> response.write("Here's the text of the Web page.
")
>>> response.write("Here's another paragraph.
")
```
#### イテレータを引き渡す
最後に、`HttpResponse` に文字列ではなくイテレータを引き渡すことができます。`HttpResponse` はイテレータをただちに消費し、その内容を文字列と保持してから破棄します。`close()` メソッドで、ファイルやジェネレータのようなオブジェクト即座に閉じられます。
レスポンスに対して、イテレータからクライアントにストリーミングさせる必要がある場合には、代わりに [`StreamingHttpResponse`](#django.http.StreamingHttpResponse) クラスを使う必要があります。
> **Changed in Django 1.10**
>
> `close()` メソッドを持つオブジェクトは、かつては WSGI サーバーがレスポンス上で `close()` を呼んだときに閉じられていました。
#### ヘッダーフィールドをセットする
レスポンス上でヘッダーフィールドをセットしたり削除するためには、ディクショナリのように扱ってください:
```
>>> response = HttpResponse()
>>> response['Age'] = 120
>>> del response['Age']
```
ディクショナリとは異なり、ヘッダーフィールドが存在しないときでも `del` が `KeyError` を投げない点に注意してください。
For setting the `Cache-Control` and `Vary` header fields, it is recommended
to use the [`patch_cache_control()`](/ja/1.11/ref/utils/#django.utils.cache.patch_cache_control) and
[`patch_vary_headers()`](/ja/1.11/ref/utils/#django.utils.cache.patch_vary_headers) methods from
[`django.utils.cache`](/ja/1.11/ref/utils/#module-django.utils.cache), since these fields can have multiple, comma-separated
values. The "patch" methods ensure that other values, e.g. added by a
middleware, are not removed.
HTTP header fields cannot contain newlines. An attempt to set a header field
containing a newline character (CR or LF) will raise `BadHeaderError`
#### Telling the browser to treat the response as a file attachment
To tell the browser to treat the response as a file attachment, use the
`content_type` argument and set the `Content-Disposition` header. For example,
this is how you might return a Microsoft Excel spreadsheet:
```
>>> response = HttpResponse(my_data, content_type='application/vnd.ms-excel')
>>> response['Content-Disposition'] = 'attachment; filename="foo.xls"'
```
There's nothing Django-specific about the `Content-Disposition` header, but
it's easy to forget the syntax, so we've included it here.
### 属性
#### `HttpResponse.content`
内容を表すバイト文字列で、必要に応じて Unicode オブジェクトからエンコードされます。
#### `HttpResponse.charset`
応答がエンコードされる文字セットを示す文字列です。 `HttpResponse` のインスタンス化の際に指定されなかった場合、`content_type` から抽出され、もしこれが失敗した場合は、`DEFAULT_CHARSET` 設定が使用されます。
#### `HttpResponse.status_code`
レスポンスの [**HTTP status code**](https://datatracker.ietf.org/doc/html/rfc7231.html#section-6) です。
[`reason_phrase`](#django.http.HttpResponse.reason_phrase) が明示的にセットされていない限り、コンストラクタの外で `status_code` の値を変更すると\`\`reason\_phrase\`\` の値も変更されます。
#### `HttpResponse.reason_phrase`
The HTTP reason phrase for the response. It uses the [**HTTP standard's**](https://datatracker.ietf.org/doc/html/rfc7231.html#section-6.1) default reason phrases.
Unless explicitly set, `reason_phrase` is determined by the value of
[`status_code`](#django.http.HttpResponse.status_code).
#### `HttpResponse.streaming`
これは常に `False` です。
この属性は、ミドルウェアが通常のレスポンスとは違う形でストリーミングレスポンスを扱えるようにするために存在しています。
#### `HttpResponse.closed`
レスポンスが閉じられた場合、`True` となります。
### メソッド
#### `HttpResponse.__init__(content='', content_type=None, status=200, reason=None, charset=None)`
Instantiates an `HttpResponse` object with the given page content and
content type.
`content` should be an iterator or a string. If it's an
iterator, it should return strings, and those strings will be
joined together to form the content of the response. If it is not
an iterator or a string, it will be converted to a string when
accessed.
`content_type` is the MIME type optionally completed by a character set
encoding and is used to fill the HTTP `Content-Type` header. If not
specified, it is formed by the [`DEFAULT_CONTENT_TYPE`](/ja/1.11/ref/settings/#std-setting-DEFAULT_CONTENT_TYPE) and
[`DEFAULT_CHARSET`](/ja/1.11/ref/settings/#std-setting-DEFAULT_CHARSET) settings, by default: "text/html; charset=utf-8".
`status` is the [**HTTP status code**](https://datatracker.ietf.org/doc/html/rfc7231.html#section-6) for the response.
`reason` is the HTTP response phrase. If not provided, a default phrase
will be used.
`charset` is the charset in which the response will be encoded. If not
given it will be extracted from `content_type`, and if that
is unsuccessful, the [`DEFAULT_CHARSET`](/ja/1.11/ref/settings/#std-setting-DEFAULT_CHARSET) setting will be used.
#### `HttpResponse.__setitem__(header, value)`
Sets the given header name to the given value. Both `header` and
`value` should be strings.
#### `HttpResponse.__delitem__(header)`
Deletes the header with the given name. Fails silently if the header
doesn't exist. Case-insensitive.
#### `HttpResponse.__getitem__(header)`
Returns the value for the given header name. Case-insensitive.
#### `HttpResponse.has_header(header)`
Returns `True` or `False` based on a case-insensitive check for a
header with the given name.
#### `HttpResponse.setdefault(header, value)`
Sets a header unless it has already been set.
#### `HttpResponse.set_cookie(key, value='', max_age=None, expires=None, path='/', domain=None, secure=None, httponly=False)`
Sets a cookie. The parameters are the same as in the
[`Morsel`](https://docs.python.org/3/library/http.cookies.html#http.cookies.Morsel) cookie object in the Python standard library.
- `max_age` should be a number of seconds, or `None` (default) if
the cookie should last only as long as the client's browser session.
If `expires` is not specified, it will be calculated.
- `expires` should either be a string in the format
`"Wdy, DD-Mon-YY HH:MM:SS GMT"` or a `datetime.datetime` object
in UTC. If `expires` is a `datetime` object, the `max_age`
will be calculated.
- Use `domain` if you want to set a cross-domain cookie. For example,
`domain=".lawrence.com"` will set a cookie that is readable by
the domains www.lawrence.com, blogs.lawrence.com and
calendars.lawrence.com. Otherwise, a cookie will only be readable by
the domain that set it.
- Use `httponly=True` if you want to prevent client-side
JavaScript from having access to the cookie.
[HTTPOnly](https://www.owasp.org/index.php/HTTPOnly) is a flag included in a Set-Cookie HTTP response
header. It is not part of the [**RFC 2109**](https://datatracker.ietf.org/doc/html/rfc2109.html) standard for cookies,
and it isn't honored consistently by all browsers. However,
when it is honored, it can be a useful way to mitigate the
risk of a client-side script from accessing the protected cookie
data.
> **Warning**
>
> Both [**RFC 2109**](https://datatracker.ietf.org/doc/html/rfc2109.html) and [**RFC 6265**](https://datatracker.ietf.org/doc/html/rfc6265.html) state that user agents should support
> cookies of at least 4096 bytes. For many browsers this is also the
> maximum size. Django will not raise an exception if there's an attempt
> to store a cookie of more than 4096 bytes, but many browsers will not
> set the cookie correctly.
#### `HttpResponse.set_signed_cookie(key, value, salt='', max_age=None, expires=None, path='/', domain=None, secure=None, httponly=False)`
Like [`set_cookie()`](#django.http.HttpResponse.set_cookie), but
[cryptographic signing](/ja/1.11/topics/signing/) the cookie before setting
it. Use in conjunction with [`HttpRequest.get_signed_cookie()`](#django.http.HttpRequest.get_signed_cookie).
You can use the optional `salt` argument for added key strength, but
you will need to remember to pass it to the corresponding
[`HttpRequest.get_signed_cookie()`](#django.http.HttpRequest.get_signed_cookie) call.
#### `HttpResponse.delete_cookie(key, path='/', domain=None)`
Deletes the cookie with the given key. Fails silently if the key doesn't
exist.
Due to the way cookies work, `path` and `domain` should be the same
values you used in `set_cookie()` -- otherwise the cookie may not be
deleted.
#### `HttpResponse.write(content)`
This method makes an [`HttpResponse`](#django.http.HttpResponse) instance a file-like object.
#### `HttpResponse.flush()`
This method makes an [`HttpResponse`](#django.http.HttpResponse) instance a file-like object.
#### `HttpResponse.tell()`
This method makes an [`HttpResponse`](#django.http.HttpResponse) instance a file-like object.
#### `HttpResponse.getvalue()`
Returns the value of [`HttpResponse.content`](#django.http.HttpResponse.content). This method makes
an [`HttpResponse`](#django.http.HttpResponse) instance a stream-like object.
#### `HttpResponse.readable()`
> **New in Django 1.10**
>
> Always `False`. This method makes an [`HttpResponse`](#django.http.HttpResponse) instance a
> stream-like object.
#### `HttpResponse.seekable()`
> **New in Django 1.10**
>
> Always `False`. This method makes an [`HttpResponse`](#django.http.HttpResponse) instance a
> stream-like object.
#### `HttpResponse.writable()`
Always `True`. This method makes an [`HttpResponse`](#django.http.HttpResponse) instance a
stream-like object.
#### `HttpResponse.writelines(lines)`
Writes a list of lines to the response. Line separators are not added. This
method makes an [`HttpResponse`](#django.http.HttpResponse) instance a stream-like object.
### `HttpResponse` subclasses
Django includes a number of `HttpResponse` subclasses that handle different
types of HTTP responses. Like `HttpResponse`, these subclasses live in
[`django.http`](#module-django.http).
#### `class HttpResponseRedirect`
The first argument to the constructor is required -- the path to redirect
to. This can be a fully qualified URL
(e.g. `'https://www.yahoo.com/search/'`), an absolute path with no domain
(e.g. `'/search/'`), or even a relative path (e.g. `'search/'`). In that
last case, the client browser will reconstruct the full URL itself
according to the current path. See [`HttpResponse`](#django.http.HttpResponse) for other optional
constructor arguments. Note that this returns an HTTP status code 302.
#### `url`
This read-only attribute represents the URL the response will redirect
to (equivalent to the `Location` response header).
#### `class HttpResponsePermanentRedirect`
Like [`HttpResponseRedirect`](#django.http.HttpResponseRedirect), but it returns a permanent redirect
(HTTP status code 301) instead of a "found" redirect (status code 302).
#### `class HttpResponseNotModified`
The constructor doesn't take any arguments and no content should be added
to this response. Use this to designate that a page hasn't been modified
since the user's last request (status code 304).
#### `class HttpResponseBadRequest`
Acts just like [`HttpResponse`](#django.http.HttpResponse) but uses a 400 status code.
#### `class HttpResponseNotFound`
Acts just like [`HttpResponse`](#django.http.HttpResponse) but uses a 404 status code.
#### `class HttpResponseForbidden`
Acts just like [`HttpResponse`](#django.http.HttpResponse) but uses a 403 status code.
#### `class HttpResponseNotAllowed`
Like [`HttpResponse`](#django.http.HttpResponse), but uses a 405 status code. The first argument
to the constructor is required: a list of permitted methods (e.g.
`['GET', 'POST']`).
#### `class HttpResponseGone`
Acts just like [`HttpResponse`](#django.http.HttpResponse) but uses a 410 status code.
#### `class HttpResponseServerError`
Acts just like [`HttpResponse`](#django.http.HttpResponse) but uses a 500 status code.
> **Note**
>
> If a custom subclass of [`HttpResponse`](#django.http.HttpResponse) implements a `render`
> method, Django will treat it as emulating a
> [`SimpleTemplateResponse`](/ja/1.11/ref/template-response/#django.template.response.SimpleTemplateResponse), and the
> `render` method must itself return a valid response object.
## `JsonResponse` objects
#### `class JsonResponse(data, encoder=DjangoJSONEncoder, safe=True, json_dumps_params=None, **kwargs)`
An [`HttpResponse`](#django.http.HttpResponse) subclass that helps to create a JSON-encoded
response. It inherits most behavior from its superclass with a couple
differences:
Its default `Content-Type` header is set to `application/json`.
The first parameter, `data`, should be a `dict` instance. If the
`safe` parameter is set to `False` (see below) it can be any
JSON-serializable object.
The `encoder`, which defaults to
[`django.core.serializers.json.DjangoJSONEncoder`](/ja/1.11/topics/serialization/#django.core.serializers.json.DjangoJSONEncoder), will be used to
serialize the data. See [JSON serialization](/ja/1.11/topics/serialization/#serialization-formats-json) for more details about this serializer.
The `safe` boolean parameter defaults to `True`. If it's set to
`False`, any object can be passed for serialization (otherwise only
`dict` instances are allowed). If `safe` is `True` and a non-`dict`
object is passed as the first argument, a [`TypeError`](https://docs.python.org/3/library/exceptions.html#TypeError) will be raised.
The `json_dumps_params` parameter is a dictionary of keyword arguments
to pass to the `json.dumps()` call used to generate the response.
### 使い方
Typical usage could look like:
```
>>> from django.http import JsonResponse
>>> response = JsonResponse({'foo': 'bar'})
>>> response.content
b'{"foo": "bar"}'
```
#### Serializing non-dictionary objects
In order to serialize objects other than `dict` you must set the `safe`
parameter to `False`:
```
>>> response = JsonResponse([1, 2, 3], safe=False)
```
Without passing `safe=False`, a [`TypeError`](https://docs.python.org/3/library/exceptions.html#TypeError) will be raised.
> **Warning**
>
> Before the [5th edition of ECMAScript](http://www.ecma-international.org/ecma-262/5.1/index.html#sec-11.1.4)
> it was possible to poison the JavaScript `Array` constructor. For this
> reason, Django does not allow passing non-dict objects to the
> [`JsonResponse`](#django.http.JsonResponse) constructor by default. However, most
> modern browsers implement EcmaScript 5 which removes this attack vector.
> Therefore it is possible to disable this security precaution.
#### Changing the default JSON encoder
If you need to use a different JSON encoder class you can pass the `encoder`
parameter to the constructor method:
```
>>> response = JsonResponse(data, encoder=MyJSONEncoder)
```
## `StreamingHttpResponse` objects
#### `class StreamingHttpResponse`
The [`StreamingHttpResponse`](#django.http.StreamingHttpResponse) class is used to stream a response from
Django to the browser. You might want to do this if generating the response
takes too long or uses too much memory. For instance, it's useful for
[generating large CSV files](/ja/1.11/howto/outputting-csv/#streaming-csv-files).
> **Performance considerations**
>
> Django is designed for short-lived requests. Streaming responses will tie
> a worker process for the entire duration of the response. This may result
> in poor performance.
>
> Generally speaking, you should perform expensive tasks outside of the
> request-response cycle, rather than resorting to a streamed response.
The [`StreamingHttpResponse`](#django.http.StreamingHttpResponse) is not a subclass of [`HttpResponse`](#django.http.HttpResponse),
because it features a slightly different API. However, it is almost identical,
with the following notable differences:
- It should be given an iterator that yields strings as content.
- You cannot access its content, except by iterating the response object
itself. This should only occur when the response is returned to the client.
- It has no `content` attribute. Instead, it has a
[`streaming_content`](#django.http.StreamingHttpResponse.streaming_content) attribute.
- You cannot use the file-like object `tell()` or `write()` methods.
Doing so will raise an exception.
[`StreamingHttpResponse`](#django.http.StreamingHttpResponse) should only be used in situations where it is
absolutely required that the whole content isn't iterated before transferring
the data to the client. Because the content can't be accessed, many
middleware can't function normally. For example the `ETag` and
`Content-Length` headers can't be generated for streaming responses.
### 属性
#### `StreamingHttpResponse.streaming_content`
An iterator of strings representing the content.
#### `StreamingHttpResponse.status_code`
レスポンスの [**HTTP status code**](https://datatracker.ietf.org/doc/html/rfc7231.html#section-6) です。
[`reason_phrase`](#django.http.StreamingHttpResponse.reason_phrase) が明示的にセットされていない限り、コンストラクタの外で `status_code` の値を変更すると\`\`reason\_phrase\`\` の値も変更されます。
#### `StreamingHttpResponse.reason_phrase`
The HTTP reason phrase for the response. It uses the [**HTTP standard's**](https://datatracker.ietf.org/doc/html/rfc7231.html#section-6.1) default reason phrases.
Unless explicitly set, `reason_phrase` is determined by the value of
[`status_code`](#django.http.StreamingHttpResponse.status_code).
#### `StreamingHttpResponse.streaming`
This is always `True`.
## `FileResponse` objects
#### `class FileResponse`
[`FileResponse`](#django.http.FileResponse) is a subclass of [`StreamingHttpResponse`](#django.http.StreamingHttpResponse) optimized
for binary files. It uses [wsgi.file\_wrapper](https://www.python.org/dev/peps/pep-3333/#optional-platform-specific-file-handling) if provided by the wsgi server,
otherwise it streams the file out in small chunks.
`FileResponse` expects a file open in binary mode like so:
```
>>> from django.http import FileResponse
>>> response = FileResponse(open('myfile.png', 'rb'))
```