Designate/pdns breaks at semicolons in DNS record TXT values

[Alexander Monk]

Downstream report: https://phabricator.wikimedia.org/T203036

To reproduce the problem, I tried to make a TXT record called "designatetesting.testlabs.wmflabs.org.", comment "Alex testing https://phabricator.wikimedia.org/T87338#4274206", value "a=b; c=d; e=f;"
It went in fine and Horizon shows it fine, but look what happens when I ask pdns about it:

alex@alex-laptop:~$ dig designatetesting.testlabs.wmflabs.org TXT @labs-ns0.wikimedia.org

; <<>> DiG 9.11.3-1ubuntu1.1-Ubuntu <<>> designatetesting.testlabs.wmflabs.org TXT @labs-ns0.wikimedia.org
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 39511
;; flags: qr aa rd; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 1
;; WARNING: recursion requested but not available

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 2800
;; QUESTION SECTION:
;designatetesting.testlabs.wmflabs.org. IN TXT

;; ANSWER SECTION:
designatetesting.testlabs.wmflabs.org. 3600 IN TXT "a=b"

;; Query time: 197 msec
;; SERVER: 208.80.155.117#53(208.80.155.117)
;; WHEN: Tue Aug 28 23:51:28 BST 2018
;; MSG SIZE rcvd: 82

It (either pdns or designate) found the first semicolon and stopped there.
I believe that's mitaka. I can ask for details of the installation from it's administrators if that would be helpful.

[Dmitry Galkin (galkindmitrii)]

probably related to https://bugs.launchpad.net/designate/+bug/1755788