calls, apps, and routes listing were previously returning the entire data set,
which just won't scale. this adds pagination with cursoring forward to each of
these endpoints (see the [docs](docs/definitions.md)).
the patch is really mostly tests, shouldn't be that bad to pick through.
some blarble about implementation is in order:
calls are sorted by ids but allow searching within certain `created_at` ranges
(finally). this is because sorting by `created_at` isn't feasible when
combined with paging, as `created_at` is not guaranteed to be unique -- id's
are (eliding theoreticals). i.e. on a page boundary, if there are 200 calls
with the same `created_at`, providing a `cursor` of that `created_at` will
skip over the remaining N calls with that `created_at`. also using id will be
better on the index anyway (well, less of them). yay having sortable ids! I
can't discern any issues doing this, as even if 200 calls have the same
created_at, they will have different ids, and the sort should allow paginating
them just fine. ids are also url safe, so the id works as the cursor value
just fine.
apps and routes are sorted by alphabetical order. as they aren't guaranteed to
be url safe, we are base64'ing them in the front end to a url safe format and
then returning them, and then base64 decoding them when we get them. this does
mean that they can be relatively large if the path/app is long, but if we
don't want to add ids then they were going to be pretty big anyway. a bonus
that this kind of obscures them. if somebody has better idea on formatting, by
all means.
notably, we are not using the sql paging facilities, and we are baking our own
based on cursors, which ends up being much more efficient for querying longer
lists of resources. this also should be easy to implement in other non-sql dbs
and the cursoring formats we can change on the fly since we are just exposing
them as opaque strings. the front end deals with the base64 / formatting, etc
and the back end is taking raw values (strfmt.DateTime or the id for calls).
the cursor that is being passed to/by the user is simply the last resource on the
previous page, so in theory we don't even need to return it, but it does make
it a little easier to use, also, cursor being blank on the last page depends
on page full-ness, so sometimes users will get a cursor when there are no
results on next page (1/N chance, and it's not really end of world -- actually
searching for the next thing would make things more complex). there are ample
tests for this behavior.
I've turned off all query parameters allowing `LIKE` queries on certain listing
endpoints, as we should not expose sql behavior through our API in the event
that we end up not using a sql db down the road. I think we should only allow
prefix matching, which sql can support as well as other types of databases
relatively cheaply, but this is not hooked up here as it didn't 'just work'
when I was fiddling with it (can add later, they're unnecessary and weren't
wired in before in front end).
* remove route listing across apps (unused)
* fix panic when doing `/app//`. this is prob possible for other types of
endpoints, out of scope here. added a guard in front of all endpoints for this
* adds `from_time` and `to_time` query parameters to calls, so you can e.g.
list the last hour of tasks. these are not required and default to
oldest/newest.
* hooked back up the datastore tests to the sql db, only run with sqlite atm,
but these are useful, added a lot to them too.
* added a bunch of tests to the front end, so pretty sure this all works now.
* added to swagger, we'll need to re-gen. also wrote some words about
pagination workings, I'm not sure how best to link to these, feedback welcome.
* not sure how we want to manage indexes, but we may need to add some (looking
at created_at, mostly)
* `?route` changed to `?path` in routes listing, to keep consistency with
everything else
* don't 404 when searching for calls where the route doesn't exist, just
return an empty list (it's a query param ffs)
closes#141
this adds `FN_` in front of env vars that we are injecting into calls, for
namespacing reasons. this will break code relying on the current variables but
if we want to do this, the chance is now really. alternatively, we could
maintain both the old and new for a short period of time to ease the
adjustment (speak now...). updated the docs, as well.
this also adds tests for the notoriously finicky configuration of the env vars
and headers when setting up a call. this won't test the container / request
for the call is actually receiving them, but it's a decent start and will yell
loudly enough upon formatting breakage.
added back FXLB_WAIT to a couple places so the lb can ride again
one thing for feedback:
headers are a bit confusing at the moment (not from this change, but that
behavior is kept here for now), we've a chance to fix them. currently, headers
in the request __are not__ prefixed with `FN_HEADER_`, i.e. 'hot'+sync containers
will receive `Content-Length` in the http request headers, yet a 'cold'
container from the same request would receive `FN_HEADER_Content-Length` in
its environment. This is additionally confusing because if this function were
hot+async, it would receive `FN_HEADER_Content-Length` in the headers, where
just changing it to sync goes back to `Content-Length`. If that was confusing,
then point made ;)
I propose to remove the `FN_HEADER_` prefix for request headers in the
environment, so that the request headers and env will match, as request
headers already are of this format (not prefixed). please lmk thoughts here
Would be fine with going back to the 'plain' vars too, then this patch will
mostly just be adding tests and changing `FN_FORMAT` to `FORMAT`. obviously,
from the examples, it's a bit ingrained now. anyway, entirely up to y'all.
* fix docker build
this is trivially incorrect since glide doesn't actually provide reproducible
builds. the idea is to build with the deps that we have checked into git, so
that we actually know what code is executing so that we might debug it...
all for multi stage build instead of what we had, but adding the glide step is
wrong. i added a loud warning so as to discourage this behavior in the future.
* hang the runner, agent=new sheriff
tl;dr agent is now runner, with a hopefully saner api
the general idea is get rid of all the various 'task' structs now, change our
terminology to only be 'calls' now, push a lot of the http construction of a
call into the agent, allow calls to mutate their state around their execution
easily and to simplify the number of code paths, channels and context timeouts
in something [hopefully] easy to understand.
this introduces the idea of 'slots' which are either hot or cold and are
separate from reserving memory (memory is denominated in 'tokens' now).
a 'slot' is essentially a container that is ready for execution of a call, be
it hot or cold (it just means different things based on hotness). taking a
look into Submit should make these relatively easy to grok.
sorry, things were pretty broken especially wrt timings. I tried to keep good
notes (maybe too good), to highlight stuff so that we don't make the same
mistakes again (history repeating itself blah blah quote). even now, there is
lots of work to do :)
I encourage just reading the agent.go code, Submit is really simple and
there's a description of how the whole thing works at the head of the file
(after TODOs). call.go contains code for constructing calls, as well as Start
/ End (small atm). I did some amount of code massaging to try to make things
simple / straightforward / fit reasonable mental model, but as always am open
to critique (the more negative the better) as I'm just one guy and wth do i
know...
-----------------------------------------------------------------------------
below enumerates a number of changes as briefly as possible (heh..):
models.Call all the things
removes models.Task as models.Call is now what it previously was.
models.FnCall is now rid of in favor of models.Call, despite the datastore
only storing a few fields of it [for now]. we should probably store entire
calls in the db, since app & route configurations can change at any given
moment, it would be nice to see the parameters of each call (costs db space,
obviously).
this removes the endpoints for getting & deleting messages, we were just
looping back to localhost to call the MQ (wtf? this was for iron integration i
think) and just calls the MQ.
changes the name of the FnLog to LogStore, confusing cause there's also a
`FuncLogger` which uses the Logstore (punting). removes other `Fn` prefixed
structs (redundant naming convention).
removes some unused and/or weird structs (IDStatus, CompleteTime)
updates the swagger
makes the db methods consistent to use 'Call' nomenclature.
remove runner nuisances:
* push down registry stuff to docker driver
* remove Environment / Stats stuff of yore
* remove unused writers (now in FuncLogger)
* remove 2 of the task types, old hot stuff, runner, etc
fixes ram available calculation on startup to not always be 300GB (helps a lot
on a laptop!)
format for DOCKER_AUTH env now is not a list but a map (there are no docs,
would prefer to get rid of this altogether anyway). the ~/.docker/cfg expected
format is unchanged.
removes arbitrary task queue, if a machine is out of ram we can probably just
time out without queueing... (can open separate discussion) in any case the
old one didn't really account well for hot tasks, it just lined everyone up in
the task queue if there wasn't a place to run hot and then timed them out
[even if a slot became free].
removes HEADER_ prefixing on any headers in the request to a invoke a call.
(this was inconsistent with cli for test anyway)
removes TASK_ID header sent in to hot only (this is a dupe of FN_CALL_ID,
which has not been removed)
now user functions can reply directly to the client. this means that for
cold containers if they write to stdout it will send a 200 + headers. for
hot containers, the user can reply directly to the client from the container,
i.e. with its preferred status code / headers (vs. always getting a 200).
the dispatch itself is a little http specific atm, i think we can add an
interchange format but the current version is easily extended to add json for
now, separate discussion. this eliminates a lot of the request/response
rewriting and buffering we were doing (yey). now Dispatch ONLY does input and
output, vs. managing the call timeout and having access to a call's fields.
cache is pushed down into agent now instead of in the front end, would like to
push it down to the datastore actually but it's here for now anyway. cache
delete functions removed (b/c fn is distributed anyway?). added app caching,
should help with latency.
in general, a lot of server/runner.go got pushed down into the agent. i think
it will be useful in testing to be able to construct calls without having to
invoke http handlers + async also needs to construct calls without a handler.
safe shutdown actually works now for everything (leaked / didn't wait on
certain things before)
now we're waiting for hot slots to open up while we're attempting to get ram
to launch a container if we didn't find any hot slots to run the call in
immediately. we can change this policy really easily now (no more channel
jungle; still some channels). also looking for somewhere else to go while the
container is launching now. slots now get sent _out_ of a container, vs.
a container receiving calls, which makes this kind of policy easier to
implement. this fixes a number of bugs around things like trying to execute
calls against containers that have not and may never start and trying to
launch a bazillion containers when there are no free containers. the driver api
underwent some changes to make this possible (relatively minimal, added Wait).
the easiest way to think about this is that allocating ram has moved 'up'
instead of just wrapping launching containers, so that we can select on a
channel trying to find ram.
not dispatching hot calls to containers that died anymore either...
the timeout is now started at the beginning of Submit, rather than Dispatch or
the container itself having to manage the call timeout, which was an
inaccurate way of doing things since finding a slot / allocating ram / pulling
image can all take a non-trivial (timeout amount, even!) amount of time. this
makes for much more reasonable response times from fn under load, there's
still a little TODO about handling cold+timeout container removal response
times but it's much improved.
if call.Start is called with < call.timeout/2 time left, then the call will
not be executed and return a timeout. we can discuss. this makes async play
_a lot_ nicer, specifically. for large timeouts / 2 makes less sense.
env is no longer getting upper cased (admittedly, this can look a little weird
now). our whole route.Config/app.Config/env/headers stuff probably deserves a
whole discussion...
sync output no longer has the call id in json if there's an error / timeout.
we could add this back to signify that it's _us_ writing these but this was
out of place. FN_CALL_ID is still shipped out to get the id for sync calls,
and async [server] output remains unchanged.
async logs are now an entire raw http request (so that a user can write a 400
or something from their hot async container)
async hot now 'just works'
cold sync calls can now reply to the client before container removal, which
shaves a lot of latency off of those (still eat start). still need to figure
out async removal if timeout or something.
-----------------------------------------------------------------------------
i've located a number of bugs that were generally inherited, and also added
a number of TODOs in the head of the agent.go file according to robustness we
probably need to add. this is at least at parity with the previous
implementation, to my knowledge (hopefully/likely a good bit ahead). I can
memorialize these to github quickly enough, not that anybody searches before
adding bugs anyway (sigh).
the big thing to work on next imo is async being a lot more robust,
specifically to survive fn server failures / network issues.
thanks for review (gulp)
* Renamed a bunch of images to use fnproject org.
* Multi-stage build for Docker.
* Added tmp vendor dirs to gitignore.
* Run docker-build at beginning of test.
* Consolidating route type utilization
Fixes: #197
* Adding --version to fn init CLI command
* Updating functions_go to 0.1.36
* Updating route init process
* Updating tests
* Adding "memory" CLI flag to fn run
* Make CLI memory flag override what's in func.yaml
* Get rid of default value for memory flag
* Revert UX impact
func.yaml remains the same, no nested maps
