Here's an example of a barebones gall agent that just starts a thread:
thread-starter.hoon
/+ default-agent, dbug
=* card card:agent:gall
%- agent:dbug
^- agent:gall
|_ =bowl:gall
+* this .
def ~(. (default-agent this %|) bowl)
::
++ on-init on-init:def
++ on-save on-save:def
++ on-load on-load:def
++ on-poke
|= [=mark =vase]
^- (quip card _this)
?+ mark (on-poke:def mark vase)
%noun
?+ q.vase (on-poke:def mark vase)
(pair term term)
=/ tid `@ta`(cat 3 'thread_' (scot %uv (sham eny.bowl)))
=/ ta-now `@ta`(scot %da now.bowl)
=/ start-args [~ `tid byk.bowl(r da+now.bowl) p.q.vase !>(q.q.vase)]
:_ this
:~
[%pass /thread/[ta-now] %agent [our.bowl %spider] %poke %spider-start !>(start-args)]
==
==
==
++ on-watch on-watch:def
++ on-leave on-leave:def
++ on-peek on-peek:def
++ on-agent
|= [=wire =sign:agent:gall]
^- (quip card _this)
?+ -.wire (on-agent:def wire sign)
%thread
?+ -.sign (on-agent:def wire sign)
%poke-ack
?~ p.sign
%- (slog leaf+"Thread started successfully" ~)
`this
%- (slog leaf+"Thread failed to start" u.p.sign)
`this
==
==
++ on-arvo on-arvo:def
++ on-fail on-fail:def
--
And here's a minimal thread to test it with:
test-thread.hoon
/- spider
=, strand=strand:spider
^- thread:spider
|= arg=vase
=/ m (strand ,vase)
^- form:m
|= strand-input:strand
?+ q.arg [~ %fail %not-foo ~]
%foo
[~ %done arg]
==
Save them as /app/thread-starter.hoon and /ted/test-thread.hoon respectively in the %base desk, |commit %base, and start the app with |rein %base [& %thread-starter].
Now you can poke it with a pair of thread name and argument like:
:thread-starter [%test-thread %foo]You should see Thread started successfully.
Now try poking it with [%fake-thread %foo], you should see something like:
Thread failed to start
/app/spider/hoon:<[355 5].[355 60]>
[%no-file-for-thread %fake-thread]
/app/spider/hoon:<[354 5].[355 60]>
/app/spider/hoon:<[353 3].[359 19]>
/app/spider/hoon:<[350 3].[359 19]>
/app/spider/hoon:<[346 3].[359 19]>
/app/spider/hoon:<[343 3].[359 19]>
/app/spider/hoon:<[341 3].[359 19]>
/app/spider/hoon:<[340 3].[359 19]>
/app/spider/hoon:<[336 3].[359 19]>
/app/spider/hoon:<[335 3].[359 19]>
/app/spider/hoon:<[202 24].[202 68]>
/app/spider/hoon:<[200 7].[207 9]>
/app/spider/hoon:<[199 5].[208 17]>
/app/spider/hoon:<[197 5].[208 17]>
/app/spider/hoon:<[196 5].[208 17]>
/sys/vane/gall/hoon:<[1.370 9].[1.370 37]>Analysis
We can ignore the input logic, here's the important part:
=/ tid `@ta`(cat 3 'thread_' (scot %uv (sham eny.bowl)))
=/ ta-now `@ta`(scot %da now.bowl)
=/ start-args [~ `tid byk.bowl(r da+now.bowl) p.q.vase !>(q.q.vase)]
:_ this
:~
[%pass /thread/[ta-now] %agent [our.bowl %spider] %poke %spider-start !>(start-args)]
==
You can generate a tid any way you like, just make sure it's unique. Here we just use the hash of some entropy prefixed with thread_.
Then it's just a poke to %spider with the mark %spider-start and a vase containing start-args. Spider will then respond with a %poke-ack with a (unit tang) which will be ~ if it started successfully or else contain an error and a traceback if it failed. Here we test for this and print the result:
++ on-agent
|= [=wire =sign:agent:gall]
^- (quip card _this)
?+ -.wire (on-agent:def wire sign)
%thread
?+ -.sign (on-agent:def wire sign)
%poke-ack
?~ p.sign
%- (slog leaf+"Thread started successfully" ~)
`this
%- (slog leaf+"Thread failed to start" u.p.sign)
`this
==
==