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diff --git a/external/unbound/pythonmod/doc/examples/example4.rst b/external/unbound/pythonmod/doc/examples/example4.rst deleted file mode 100644 index 338210990..000000000 --- a/external/unbound/pythonmod/doc/examples/example4.rst +++ /dev/null @@ -1,178 +0,0 @@ -DNS-based language dictionary -============================= - -This example shows how to create a simple language dictionary based on **DNS** -service within 15 minutes. The translation will be performed using TXT resource -records. - -Key parts ---------- - -Initialization -~~~~~~~~~~~~~~ - -On **init()** module loads dictionary from a text file containing records in -``word [tab] translation`` format. - -:: - - def init(id, cfg): - log_info("pythonmod: dict init") - f = open("examples/dict_data.txt", "r") - ... - -The suitable file can be found at http://slovnik.zcu.cz - -DNS query and word lookup -~~~~~~~~~~~~~~~~~~~~~~~~~ - -Let's define the following format od DNS queries: -``word1[.]word2[.] ... wordN[.]{en,cs}[._dict_.cz.]``. -Word lookup is done by simple ``dict`` lookup from broken DNS request. -Query name is divided into a list of labels. This list is accessible as -``qname_list`` attribute. - -:: - - aword = ' '.join(qstate.qinfo.qname_list[0:-4]) #skip last four labels - adict = qstate.qinfo.qname_list[-4] #get 4th label from the end - - words = [] #list of words - if (adict == "en") and (aword in en_dict): - words = en_dict[aword] - - if (adict == "cs") and (aword in cz_dict): - words = cz_dict[aword] # CS -> EN - -In the first step, we get a string in the form: -``word1[space]word2[space]...word[space]``. -In the second assignment, fourth label from the end is obtained. This label -should contains *"cs"* or *"en"*. This label determines the direction of -translation. - -Forming of a DNS reply -~~~~~~~~~~~~~~~~~~~~~~ - -DNS reply is formed only on valid match and added as TXT answer. - -:: - - msg = DNSMessage(qstate.qinfo.qname_str, RR_TYPE_TXT, RR_CLASS_IN, PKT_AA) - - for w in words: - msg.answer.append("%s 300 IN TXT \"%s\"" % (qstate.qinfo.qname_str, w.replace("\"", "\\\""))) - - if not msg.set_return_msg(qstate): - qstate.ext_state[id] = MODULE_ERROR - return True - - qstate.return_rcode = RCODE_NOERROR - qstate.ext_state[id] = MODULE_FINISHED - return True - -In the first step, a :class:`DNSMessage` instance is created for a given query -*(type TXT)*. -The fourth argument specifies the flags *(authoritative answer)*. -In the second step, we append TXT records containing the translation *(on the -right side of RR)*. -Then, the response is finished and ``qstate.return_msg`` contains new response. -If no error, the module sets :attr:`module_qstate.return_rcode` and -:attr:`module_qstate.ext_state`. - -**Steps:** - -1. create :class:`DNSMessage` instance -2. append TXT records containing the translation -3. set response to ``qstate.return_msg`` - -Testing -------- - -Run the Unbound server: - -``root@localhost>unbound -dv -c ./test-dict.conf`` - -In case you use own configuration file, don't forget to enable Python module:: - - module-config: "validator python iterator" - -and use valid script path:: - - python-script: "./examples/dict.py" - -The translation from english word *"a bar fly"* to Czech can be done by doing: - -``>>>dig TXT @127.0.0.1 a.bar.fly.en._dict_.cz`` - -:: - - ; (1 server found) - ;; global options: printcmd - ;; Got answer: - ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 48691 - ;; flags: aa rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 0 - - ;; QUESTION SECTION: - ;a.bar.fly.en._dict_.cz. IN TXT - - ;; ANSWER SECTION: - a.bar.fly.en._dict_.cz. 300 IN TXT "barov\253 povale\232" - - ;; Query time: 5 msec - ;; SERVER: 127.0.0.1#53(127.0.0.1) - ;; WHEN: Mon Jan 01 17:44:18 2009 - ;; MSG SIZE rcvd: 67 - -``>>>dig TXT @127.0.0.1 nic.cs._dict_.cz`` - -:: - - ; <<>> DiG 9.5.0-P2 <<>> TXT @127.0.0.1 nic.cs._dict_.cz - ; (1 server found) - ;; global options: printcmd - ;; Got answer: - ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 58710 - ;; flags: aa rd ra; QUERY: 1, ANSWER: 6, AUTHORITY: 0, ADDITIONAL: 0 - - ;; QUESTION SECTION: - ;nic.cs._dict_.cz. IN TXT - - ;; ANSWER SECTION: - nic.cs._dict_.cz. 300 IN TXT "aught" - nic.cs._dict_.cz. 300 IN TXT "naught" - nic.cs._dict_.cz. 300 IN TXT "nihil" - nic.cs._dict_.cz. 300 IN TXT "nix" - nic.cs._dict_.cz. 300 IN TXT "nothing" - nic.cs._dict_.cz. 300 IN TXT "zilch" - - ;; Query time: 0 msec - ;; SERVER: 127.0.0.1#53(127.0.0.1) - ;; WHEN: Mon Jan 01 17:45:39 2009 - ;; MSG SIZE rcvd: 143 - - Proof that the unbound still works as resolver. - -``>>>dig A @127.0.0.1 www.nic.cz`` - -:: - - ; (1 server found) - ;; global options: printcmd - ;; Got answer: - ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 19996 - ;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 3, ADDITIONAL: 5 - - ;; QUESTION SECTION: - ;www.nic.cz. IN A - - ;; ANSWER SECTION: - www.nic.cz. 1662 IN A 217.31.205.50 - - ;; AUTHORITY SECTION: - ... - -Complete source code --------------------- - -.. literalinclude:: ../../examples/dict.py - :language: python |