# Curl Object

class pycurl.Curl

  Creates a new Curl Object which corresponds to a `CURL` handle in libcurl. Curl objects automatically set CURLOPT_VERBOSE to 0, CURLOPT_NOPROGRESS to 1, provide a default CURLOPT_USERAGENT and setup CURLOPT_ERRORBUFFER to point to a private error buffer.

  Implicitly calls `pycurl.global_init()` if the latter has not yet been called.

  Curl objects have the following methods:

  close() → None

    Close handle and end curl session.

    Corresponds to curl_easy_cleanup in libcurl. This method is automatically called by pycurl when a Curl object no longer has any references to it, but can also be called explicitly.

  setopt(option, value) → None

    Set curl session option. Corresponds to curl_easy_setopt in libcurl.

    option specifies which option to set. PycURL defines constants corresponding to `CURLOPT_*` constants in libcurl, except that the `CURLOPT_` prefix is removed. For example, `CURLOPT_URL` is exposed in PycURL as `pycurl.URL`, with some exceptions as detailed below. For convenience, `CURLOPT_*` constants are also exposed on the Curl objects themselves:

        import pycurl
        c = pycurl.Curl()
        c.setopt(pycurl.URL, "http://www.python.org/")
        # Same as:
        c.setopt(c.URL, "http://www.python.org/")

    The following are exceptions to option constant naming convention:

    - `CURLOPT_FILETIME` is mapped as `pycurl.OPT_FILETIME`

    - `CURLOPT_CERTINFO` is mapped as `pycurl.OPT_CERTINFO`

    - `CURLOPT_COOKIELIST` is mapped as `pycurl.COOKIELIST` and, as of PycURL 7.43.0.2, also as `pycurl.OPT_COOKIELIST`

    - `CURLOPT_RTSP_CLIENT_CSEQ` is mapped as `pycurl.OPT_RTSP_CLIENT_CSEQ`

    - `CURLOPT_RTSP_REQUEST` is mapped as `pycurl.OPT_RTSP_REQUEST`

    - `CURLOPT_RTSP_SERVER_CSEQ` is mapped as `pycurl.OPT_RTSP_SERVER_CSEQ`

    - `CURLOPT_RTSP_SESSION_ID` is mapped as `pycurl.OPT_RTSP_SESSION_ID`

    - `CURLOPT_RTSP_STREAM_URI` is mapped as `pycurl.OPT_RTSP_STREAM_URI`

    - `CURLOPT_RTSP_TRANSPORT` is mapped as `pycurl.OPT_RTSP_TRANSPORT`

    value specifies the value to set the option to. Different options accept values of different types:

    - Options specified by curl_easy_setopt as accepting `1` or an integer value accept Python integers, long integers (on Python 2.x) and booleans:

          c.setopt(pycurl.FOLLOWLOCATION, True)
          c.setopt(pycurl.FOLLOWLOCATION, 1)
          # Python 2.x only:
          c.setopt(pycurl.FOLLOWLOCATION, 1L)

    - Options specified as accepting strings by `curl_easy_setopt` accept byte strings (`str` on Python 2, `bytes` on Python 3) and Unicode strings with ASCII code points only. For more information, please refer to String And Unicode Handling. Example:

          c.setopt(pycurl.URL, "http://www.python.org/")
          c.setopt(pycurl.URL, u"http://www.python.org/")
          # Python 3.x only:
          c.setopt(pycurl.URL, b"http://www.python.org/")

    - `HTTP200ALIASES`, `HTTPHEADER`, `POSTQUOTE`, `PREQUOTE`, `PROXYHEADER` and `QUOTE` accept a list or tuple of strings. The same rules apply to these strings as do to string option values. Example:

          c.setopt(pycurl.HTTPHEADER, ["Accept:"])
          c.setopt(pycurl.HTTPHEADER, ("Accept:",))

    - `READDATA` accepts a file object or any Python object which has a `read` method. On Python 2, a file object will be passed directly to libcurl and may result in greater transfer efficiency, unless PycURL has been compiled with `AVOID_STDIO` option. On Python 3 and on Python 2 when the value is not a true file object, `READDATA` is emulated in PycURL via `READFUNCTION`. The file should generally be opened in binary mode. Example:

          f = open('file.txt', 'rb')
          c.setopt(c.READDATA, f)

    - `WRITEDATA` and `WRITEHEADER` accept a file object or any Python object which has a `write` method. On Python 2, a file object will be passed directly to libcurl and may result in greater transfer efficiency, unless PycURL has been compiled with `AVOID_STDIO` option. On Python 3 and on Python 2 when the value is not a true file object, `WRITEDATA` is emulated in PycURL via `WRITEFUNCTION`. The file should generally be opened in binary mode. Example:

          f = open('/dev/null', 'wb')
          c.setopt(c.WRITEDATA, f)

    - `*FUNCTION` options accept a function. Supported callbacks are documented in Callbacks. Example:

          # Python 2
          import StringIO
          b = StringIO.StringIO()
          c.setopt(pycurl.WRITEFUNCTION, b.write)

    - `SHARE` option accepts a CurlShare Object.

    - `STDERR` option is not currently supported.

    It is possible to set integer options - and only them - that PycURL does not know about by using the numeric value of the option constant directly. For example, `pycurl.VERBOSE` has the value 42, and may be set as follows:

        c.setopt(42, 1)

    setopt can reset some options to their default value, performing the job of `pycurl.Curl.unsetopt()`, if `None` is passed for the option value. The following two calls are equivalent:

        c.setopt(c.URL, None)
        c.unsetopt(c.URL)

    Raises TypeError when the option value is not of a type accepted by the respective option, and pycurl.error exception when libcurl rejects the option or its value.

  perform() → None

    Perform a file transfer.

    Corresponds to curl_easy_perform in libcurl.

    Raises pycurl.error exception upon failure.

  perform_rb() → response_body

    Perform a file transfer and return response body as a byte string.

    This method arranges for response body to be saved in a StringIO (Python 2) or BytesIO (Python 3) instance, then invokes perform to perform the file transfer, then returns the value of the StringIO/BytesIO instance which is a `str` instance on Python 2 and `bytes` instance on Python 3. Errors during transfer raise `pycurl.error` exceptions just like in perform.

    Use perform_rs to retrieve response body as a string (`str` instance on both Python 2 and 3).

    Raises `pycurl.error` exception upon failure.

    Added in version 7.43.0.2.

  perform_rs() → response_body

    Perform a file transfer and return response body as a string.

    On Python 2, this method arranges for response body to be saved in a StringIO instance, then invokes perform to perform the file transfer, then returns the value of the StringIO instance. This behavior is identical to perform_rb.

    On Python 3, this method arranges for response body to be saved in a BytesIO instance, then invokes perform to perform the file transfer, then decodes the response body in Python’s default encoding and returns the decoded body as a Unicode string (`str` instance). Note: decoding happens after the transfer finishes, thus an encoding error implies the transfer/network operation succeeded.

    Any transfer errors raise `pycurl.error` exception, just like in perform.

    Use perform_rb to retrieve response body as a byte string (`bytes` instance on Python 3) without attempting to decode it.

    Raises `pycurl.error` exception upon failure.

    Added in version 7.43.0.2.

  getinfo(option) → Result

    Extract and return information from a curl session, decoding string data in Python’s default encoding at the time of the call. Corresponds to curl_easy_getinfo in libcurl. The `getinfo` method should not be called unless `perform` has been called and finished.

    option is a constant corresponding to one of the `CURLINFO_*` constants in libcurl. Most option constant names match the respective `CURLINFO_*` constant names with the `CURLINFO_` prefix removed, for example `CURLINFO_CONTENT_TYPE` is accessible as `pycurl.CONTENT_TYPE`. Exceptions to this rule are as follows:

    - `CURLINFO_FILETIME` is mapped as `pycurl.INFO_FILETIME`

    - `CURLINFO_COOKIELIST` is mapped as `pycurl.INFO_COOKIELIST`

    - `CURLINFO_CERTINFO` is mapped as `pycurl.INFO_CERTINFO`

    - `CURLINFO_RTSP_CLIENT_CSEQ` is mapped as `pycurl.INFO_RTSP_CLIENT_CSEQ`

    - `CURLINFO_RTSP_CSEQ_RECV` is mapped as `pycurl.INFO_RTSP_CSEQ_RECV`

    - `CURLINFO_RTSP_SERVER_CSEQ` is mapped as `pycurl.INFO_RTSP_SERVER_CSEQ`

    - `CURLINFO_RTSP_SESSION_ID` is mapped as `pycurl.INFO_RTSP_SESSION_ID`

    The type of return value depends on the option, as follows:

    - Options documented by libcurl to return an integer value return a Python integer (`long` on Python 2, `int` on Python 3).

    - Options documented by libcurl to return a floating point value return a Python `float`.

    - Options documented by libcurl to return a string value return a Python string (`str` on Python 2 and Python 3). On Python 2, the string contains whatever data libcurl returned. On Python 3, the data returned by libcurl is decoded using the default string encoding at the time of the call. If the data cannot be decoded using the default encoding, `UnicodeDecodeError` is raised. Use getinfo_raw to retrieve the data as `bytes` in these cases.

    - `SSL_ENGINES` and `INFO_COOKIELIST` return a list of strings. The same encoding caveats apply; use getinfo_raw to retrieve the data as a list of byte strings.

    - `INFO_CERTINFO` returns a list with one element per certificate in the chain, starting with the leaf; each element is a sequence of (key, value) tuples where both `key` and `value` are strings. String encoding caveats apply; use getinfo_raw to retrieve certificate data as byte strings.

    On Python 2, `getinfo` and `getinfo_raw` behave identically.

    Example usage:

        import pycurl
        c = pycurl.Curl()
        c.setopt(pycurl.OPT_CERTINFO, 1)
        c.setopt(pycurl.URL, "https://python.org")
        c.setopt(pycurl.FOLLOWLOCATION, 1)
        c.perform()
        print(c.getinfo(pycurl.HTTP_CODE))
        # --> 200
        print(c.getinfo(pycurl.EFFECTIVE_URL))
        # --> "https://www.python.org/"
        certinfo = c.getinfo(pycurl.INFO_CERTINFO)
        print(certinfo)
        # --> [(('Subject', 'C = AU, ST = Some-State, O = PycURL test suite,
                 CN = localhost'), ('Issuer', 'C = AU, ST = Some-State,
                 O = PycURL test suite, OU = localhost, CN = localhost'),
                ('Version', '0'), ...)]

    Raises pycurl.error exception upon failure.

  getinfo_raw(option) → Result

    Extract and return information from a curl session, returning string data as byte strings. Corresponds to curl_easy_getinfo in libcurl. The `getinfo_raw` method should not be called unless `perform` has been called and finished.

    option is a constant corresponding to one of the `CURLINFO_*` constants in libcurl. Most option constant names match the respective `CURLINFO_*` constant names with the `CURLINFO_` prefix removed, for example `CURLINFO_CONTENT_TYPE` is accessible as `pycurl.CONTENT_TYPE`. Exceptions to this rule are as follows:

    - `CURLINFO_FILETIME` is mapped as `pycurl.INFO_FILETIME`

    - `CURLINFO_COOKIELIST` is mapped as `pycurl.INFO_COOKIELIST`

    - `CURLINFO_CERTINFO` is mapped as `pycurl.INFO_CERTINFO`

    - `CURLINFO_RTSP_CLIENT_CSEQ` is mapped as `pycurl.INFO_RTSP_CLIENT_CSEQ`

    - `CURLINFO_RTSP_CSEQ_RECV` is mapped as `pycurl.INFO_RTSP_CSEQ_RECV`

    - `CURLINFO_RTSP_SERVER_CSEQ` is mapped as `pycurl.INFO_RTSP_SERVER_CSEQ`

    - `CURLINFO_RTSP_SESSION_ID` is mapped as `pycurl.INFO_RTSP_SESSION_ID`

    The type of return value depends on the option, as follows:

    - Options documented by libcurl to return an integer value return a Python integer (`long` on Python 2, `int` on Python 3).

    - Options documented by libcurl to return a floating point value return a Python `float`.

    - Options documented by libcurl to return a string value return a Python byte string (`str` on Python 2, `bytes` on Python 3). The string contains whatever data libcurl returned. Use getinfo to retrieve this data as a Unicode string on Python 3.

    - `SSL_ENGINES` and `INFO_COOKIELIST` return a list of byte strings. The same encoding caveats apply; use getinfo to retrieve the data as a list of potentially Unicode strings.

    - `INFO_CERTINFO` returns a list with one element per certificate in the chain, starting with the leaf; each element is a sequence of (key, value) tuples where both `key` and `value` are byte strings. String encoding caveats apply; use getinfo to retrieve certificate data as potentially Unicode strings.

    On Python 2, `getinfo` and `getinfo_raw` behave identically.

    Example usage:

        import pycurl
        c = pycurl.Curl()
        c.setopt(pycurl.OPT_CERTINFO, 1)
        c.setopt(pycurl.URL, "https://python.org")
        c.setopt(pycurl.FOLLOWLOCATION, 1)
        c.perform()
        print(c.getinfo_raw(pycurl.HTTP_CODE))
        # --> 200
        print(c.getinfo_raw(pycurl.EFFECTIVE_URL))
        # --> b"https://www.python.org/"
        certinfo = c.getinfo_raw(pycurl.INFO_CERTINFO)
        print(certinfo)
        # --> [((b'Subject', b'C = AU, ST = Some-State, O = PycURL test suite,
                 CN = localhost'), (b'Issuer', b'C = AU, ST = Some-State,
                 O = PycURL test suite, OU = localhost, CN = localhost'),
                (b'Version', b'0'), ...)]

    Raises pycurl.error exception upon failure.

    Added in version 7.43.0.2.

  reset() → None

    Reset all options set on curl handle to default values, but preserves live connections, session ID cache, DNS cache, cookies, and shares.

    Corresponds to curl_easy_reset in libcurl.

  unsetopt(option) → None

    Reset curl session option to its default value.

    Only some curl options may be reset via this method.

    libcurl does not provide a general way to reset a single option to its default value; `pycurl.Curl.reset()` resets all options to their default values, otherwise `pycurl.Curl.setopt()` must be called with whatever value is the default. For convenience, PycURL provides this unsetopt method to reset some of the options to their default values.

    Raises pycurl.error exception on failure.

    `c.unsetopt(option)` is equivalent to `c.setopt(option, None)`.

  pause(bitmask) → None

    Pause or unpause a curl handle. Bitmask should be a value such as PAUSE_RECV or PAUSE_CONT.

    Corresponds to curl_easy_pause in libcurl. The argument should be derived from the `PAUSE_RECV`, `PAUSE_SEND`, `PAUSE_ALL` and `PAUSE_CONT` constants.

    Raises pycurl.error exception upon failure.

  errstr() → string

    Return the internal libcurl error buffer of this handle as a string.

    Return value is a `str` instance on all Python versions. On Python 3, error buffer data is decoded using Python’s default encoding at the time of the call. If this decoding fails, `UnicodeDecodeError` is raised. Use errstr_raw to retrieve the error buffer as a byte string in this case.

    On Python 2, `errstr` and `errstr_raw` behave identically.

  errstr_raw() → byte string

    Return the internal libcurl error buffer of this handle as a byte string.

    Return value is a `str` instance on Python 2 and `bytes` instance on Python 3. Unlike errstr_raw, `errstr_raw` allows reading libcurl error buffer in Python 3 when its contents is not valid in Python’s default encoding.

    On Python 2, `errstr` and `errstr_raw` behave identically.

    Added in version 7.43.0.2.

  setopt_string(option, value) → None

    Set curl session option to a string value.

    This method allows setting string options that are not officially supported by PycURL, for example because they did not exist when the version of PycURL being used was released. `pycurl.Curl.setopt()` should be used for setting options that PycURL knows about.

    Warning: No checking is performed that option does, in fact, expect a string value. Using this method incorrectly can crash the program and may lead to a security vulnerability. Furthermore, it is on the application to ensure that the value object does not get garbage collected while libcurl is using it. libcurl copies most string options but not all; one option whose value is not copied by libcurl is CURLOPT_POSTFIELDS.

    option would generally need to be given as an integer literal rather than a symbolic constant.

    value can be a binary string or a Unicode string using ASCII code points, same as with string options given to PycURL elsewhere.

    Example setting URL via `setopt_string`:

        import pycurl
        c = pycurl.Curl()
        c.setopt_string(10002, "http://www.python.org/")