Agunua is a Python library for the development of Gemini clients.
You need Python 3, PySocks, PyOpenSSL and netaddr. You can install the dependencies with pip `pip3 install agunua`.
Parameters in the `GeminiUri()` constructor (you can find their
default values at the beginning of the file `Agunua/__init__.py`):
- `url`: the URL to load
- `insecure`: accept invalid certificates (signed by unknown CA, for instance)
- `tofu`: performs TOFU (Trust On First Use) validation
- `accept_expired`: accept expired certificates (`insecure = True` is not sufficient for that)
- `get_content`: retrieve the actual resource (default is to get metadata only)
- `parse_content`: if it is gemtext (text/gemini), parse and extract links
- `maxlines`: if it is text, maximum number of lines retrieved. Set to None if you don't want a limit
- `maxsize`: maximum size in bytes to retrieve. Set to None if you don't want a limit
- `binary`: (automatic if the content is text). Retrieve as binary content, don't play with end-of-lines
- `follow-redirect`: automatically follow Gemini redirections
- `redirect_depth`: maximum number of redirections followed
- `iri`: handle IRI (URI in Unicode)
- `force_ipv4`: use the IPv4 protocol only
- `force_ipv6`: use the IPv6 protocol only
- `send_sni`: send the TLS Server Name Indication
- `connect_to`: use the host name in the URI for the Gemini request but connect only to this host (name or address). Useful when the host is multihomed.
- `clientcert`: the filename of a client certificate that will be sent to the server.
- `clientkey`: the filename of the private key of the above certificate.
- `use_socks`: use a SOCKS5 proxy (for instance for `.onion` capsules). The value must be a tuple (socks proxy name, socks proxy port).
If the URL is invalid (wrong syntax), you won't get a `GeminiUri` object. If you get one, it does not mean the resource has been retrieved successfully. See the attribute `network_success` for that, and then the attribute `status_code` (that you have to interpret yourself, in most cases).
Attributes of `GeminiUri` objects (not all of them will always be present; for instance, if you did not ask to get content, you won't have an attribute `size`; if the status code is not 20 - OK - you won't get a mediatype; etc):
- `network_success`: resource was retrieved successfully
- `status_code`: if retrieved successfully, the Gemini two-digit status code
- `error`: if `network_success` is false, this is the reason
- `ip_address`: IP address used for the retrieval (except is SOCKS was used)
- `meta`: the `meta` field of the Gemini protocol. It depends on the status code. Read the Gemini specification for detail.
- `binary`: if you asked for binary access, it will be True. If you asked for text access (binary=False in the constructor) and asked to ge the content (get_content=True), it will be set to False if decoding went well and True if the decoding failed, for instance because the file did not match the announced "charset".
- `links`: an array of the links found in the document (if you've set `parse_content`)
- `payload`: the content
- `size`: the size of the payload. Since Gemini does not have a way to indicate at the beginning the payload size, this will be obtained only if `get_content`is true, and it will be limited by the parameter `maxsize`
- `mediatype`: the media type (MIME type) of the resource, such as `text/gemini` or `image/jpeg`
- `lang`: the human language of the resource, as standardized in BCP 47
- `charset`: actually the encoding of the resource such as UTF-8 or US-ASCII
- `tls_version`: the TLS version, for instance, "TLSv1.3"
- `no_shutdown`: set to True if the server did not properly close the TLS session. It may mean that the content was truncated. Meaningful only with `get_content=True` and if you asked for the whole file.
- The rest is related to certificates:
- `issuer`: the CA (Certificate Authority)
- `subject`: the name in the certificate (X.509 calls it "subject")
- `cert_not_after`: expiration date
- `cert_not_before`: inception date
- `cert_algo`: algorithm used by the CA
- `cert_key_type`: algorithm of the public key
- `keystring`: the public key
- `cert_key_size`: size of the public key
BCP 47 (RFC on codes for languages)
See `sample-client.py`. (In the source code, the test suite under `tests/` is also a good way to learn about how to use the library.) Agunua is used in the Manisha monitoring tool and in the Lupa crawler.
`agunua` is a simple Gemini command-line client, a bit like curl. Most parameters of the library `GeminiUri()` constructor can be set via options. Important: the default value is not always the same with the command-line tool. For instance, it defaults to actually retrieving the content.
Details on the command-line client
Download an entire capsule
Another command-line client, `geminitrack`, allows you to retrieve an entire capsule, for instance for backups.
Details on geminitrack
Agunua is a melanesian serpent god. Caduceus would have been better for a Python + Gemini project since there are two snakes on a caduceus but it was already used.
GPL. See LICENSE.
Stéphane Bortzmeyer <email@example.com>.
Gitlab site on the Web.
Use the Gitlab issue tracker to report bugs or wishes.
Reference site on Gemini
Other Gemini clients in Python