Curl Object¶

class pycurl.Curl → New Curl object¶

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.

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/")

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