add peertube engine

[mikeri]

What does this PR do?

Adds a peertube engine

Why is this change important?

This will let users search for videos on peertube

How to test this PR locally?

Perform a video search

[kvch]

When I tested this engine I got the following error:

ERROR:searx.search:engine peertube : requests exception(search duration : 0.5958149433135986 s, timeout: 2.0 s): HTTPSConnectionPool(host='peertube.live', port=443): Max retries exceeded with url: /api/v1/search/videos/?pageno
=0&search=horse&languageOneOf=hu (Caused by SSLError(SSLError("bad handshake: Error([('SSL routines', 'tls_process_server_certificate', 'certificate verify failed')],)",),))
Traceback (most recent call last):
  File "/home/n/p/searx/venv3.6/lib/python3.6/site-packages/urllib3/contrib/pyopenssl.py", line 485, in wrap_socket
    cnx.do_handshake()
  File "/home/n/p/searx/venv3.6/lib/python3.6/site-packages/OpenSSL/SSL.py", line 1915, in do_handshake
    self._raise_ssl_error(self._ssl, result)
  File "/home/n/p/searx/venv3.6/lib/python3.6/site-packages/OpenSSL/SSL.py", line 1647, in _raise_ssl_error
    _raise_current_error()
  File "/home/n/p/searx/venv3.6/lib/python3.6/site-packages/OpenSSL/_util.py", line 54, in exception_from_error_queue
    raise exception_type(errors)
OpenSSL.SSL.Error: [('SSL routines', 'tls_process_server_certificate', 'certificate verify failed')]

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/home/n/p/searx/venv3.6/lib/python3.6/site-packages/urllib3/connectionpool.py", line 672, in urlopen
    chunked=chunked,
  File "/home/n/p/searx/venv3.6/lib/python3.6/site-packages/urllib3/connectionpool.py", line 376, in _make_request
    self._validate_conn(conn)
  File "/home/n/p/searx/venv3.6/lib/python3.6/site-packages/urllib3/connectionpool.py", line 994, in _validate_conn
    conn.connect()
  File "/home/n/p/searx/venv3.6/lib/python3.6/site-packages/urllib3/connection.py", line 360, in connect
    ssl_context=context,
  File "/home/n/p/searx/venv3.6/lib/python3.6/site-packages/urllib3/util/ssl_.py", line 370, in ssl_wrap_socket
    return context.wrap_socket(sock, server_hostname=server_hostname)
  File "/home/n/p/searx/venv3.6/lib/python3.6/site-packages/urllib3/contrib/pyopenssl.py", line 491, in wrap_socket
    raise ssl.SSLError("bad handshake: %r" % e)
ssl.SSLError: ("bad handshake: Error([('SSL routines', 'tls_process_server_certificate', 'certificate verify failed')],)",)

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/home/n/p/searx/venv3.6/lib/python3.6/site-packages/requests/adapters.py", line 449, in send
    timeout=timeout
  File "/home/n/p/searx/venv3.6/lib/python3.6/site-packages/urllib3/connectionpool.py", line 720, in urlopen
    method, url, error=e, _pool=self, _stacktrace=sys.exc_info()[2]
  File "/home/n/p/searx/venv3.6/lib/python3.6/site-packages/urllib3/util/retry.py", line 436, in increment
    raise MaxRetryError(_pool, url, error or ResponseError(cause))
urllib3.exceptions.MaxRetryError: HTTPSConnectionPool(host='peertube.live', port=443): Max retries exceeded with url: /api/v1/search/videos/?pageno=0&search=horse&languageOneOf=hu (Caused by SSLError(SSLError("bad handshake: E
rror([('SSL routines', 'tls_process_server_certificate', 'certificate verify failed')],)",),))

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/home/n/p/searx/searx/search.py", line 160, in search_one_http_request_safe
    search_results = search_one_http_request(engine, query, request_params)
  File "/home/n/p/searx/searx/search.py", line 97, in search_one_http_request
    response = send_http_request(engine, request_params)
  File "/home/n/p/searx/searx/search.py", line 81, in send_http_request
    return req(request_params['url'], **request_args)
  File "/home/n/p/searx/searx/poolrequests.py", line 133, in get
    return request('get', url, **kwargs)
  File "/home/n/p/searx/searx/poolrequests.py", line 109, in request
    response = session.request(method=method, url=url, **kwargs)
  File "/home/n/p/searx/venv3.6/lib/python3.6/site-packages/requests/sessions.py", line 533, in request
    resp = self.send(prep, **send_kwargs)
  File "/home/n/p/searx/venv3.6/lib/python3.6/site-packages/requests/sessions.py", line 646, in send
    r = adapter.send(request, **kwargs)
  File "/home/n/p/searx/venv3.6/lib/python3.6/site-packages/requests/adapters.py", line 514, in send
    raise SSLError(e, request=request)
requests.exceptions.SSLError: HTTPSConnectionPool(host='peertube.live', port=443): Max retries exceeded with url: /api/v1/search/videos/?pageno=0&search=horse&languageOneOf=hu (Caused by SSLError(SSLError("bad handshake: Error
([('SSL routines', 'tls_process_server_certificate', 'certificate verify failed')],)",),))

It seems that the service does not provide a proper HTTPS connection. Do you mind changing the base_url? Also, could you please set it to be disabled by default?

[mikeri]

Indeed, the peertube.live certificate expired on August 1st, after I pushed the commit. Hence the issue is related to that specific peertube instance, not to the engine. I've changed the default base_url to peer.tube (although I have the impression peertube.live is usually a better/faster instance) and disabled the peertube engine in settings.yml.

[kvch]

Thank you!