* return bad function http resp error
this was being thrown into the fn server logs but it's relatively easy to get
this to crop up if a function user forgets that they left a `println` laying
around that gets written to stdout, it garbles the http (or json, in its case)
output and they just see 'internal server error'. for certain clients i could
see that we really do want to keep this as 'internal server error' but for
things like e.g. docker image not authorized we're showing that in the
response, so this seems apt.
json likely needs the same treatment, will file a bug.
as always, my error messages are rarely helpful enough, help me please :)
closes#355
* add formatting directive
* fix up http error
* output bad jasons to user
closes#729
woo
* pipe swapparoo each slot
previously, we made a pair of pipes for stdin and stdout for each container,
and then handed them out to each call (slot) to use. this meant that multiple
calls could have a handle on the same stdin pipe and stdout pipe to read/write
to/from from fn's perspective and could mix input/output and get garbage. this
also meant that each was blocked on the previous' reads.
now we make a new pipe every time we get a slot, and swap it out with the
previous ones. calls are no longer blocked from fn's perspective, and we don't
have to worry about timing out dispatch for any hot format. there is still the
issue that if a function does not finish reading the input from the previous
task, from its perspective, and reads the next call's it can error out the
second call. with fn deadline we provide the necessary tools to skirt this,
but without some additional coordination am not sure this is a closable hole
with our current protocols since terminating a previous calls input requires
some protocol specific bytes to go in (json in particular is tricky). anyway,
from fn's side fixing pipes was definitely a hole, but this client hole is
still hanging out. there was an attempt to send an io.EOF but the issue is
that will shut down docker's read on the stdin pipe (and the container). poop.
this adds a test for this behavior, and makes sure 2 containers don't get
launched.
this also closes the response writer header race a little, but not entirely, I
think there's still a chance that we read a full response from a function and
get a timeout while we're changing the headers. I guess we need a thread safe
header bucket, otherwise we have to rely on timings (racy). thinking on it.
* fix stats mu race
* Improve deadline handling in streaming protocols
* Move special headers handling down to the protocols
* Adding function format documentation for JSON changes
* Add tests for request url and method in JSON protocol
* Fix protocol missing fn-specific info
* Fix import
* Add panic for something that should never happen
we were using the httputil.DumpRequest when there is a perfectly good
req.Write method hanging out in the stdlib, that even does the chunked thing
that a few people ran into if they don't provide a content length:
https://golang.org/pkg/net/http/#Request.Write -- so we shouldn't run into
that issue again. I hit this in testing and it was not very fun to debug, so
added a test that repro'd it on master and fixes it here. of course, adding a
content length works too. tested this and it appears to work pretty well, also
cleaned up the control flow a little bit in http protocol.
possible breakages:
* `FN_HEADER` on cold are no longer `s/-/_/` -- this is so that cold functions
can rebuild the headers as they were when they came in on the request (fdks,
specifically), there's no guarantee that a reversal `s/_/-/` is the original
header on the request.
* app and route config no longer `s/-/_/` -- it seemed really weird to rewrite
the users config vars on these. should just pass them exactly as is to env.
* headers no longer contain the environment vars (previously, base config; app
config, route config, `FN_PATH`, etc.), these are still available in the
environment.
this gets rid of a lot of the code around headers, specifically the stuff that
shoved everything into headers when constructing a call to begin with. now we
just store the headers separately and add a few things, like FN_CALL_ID to
them, and build a separate 'config' now to store on the call. I thought
'config' was more aptly named, 'env' was confusing, though now 'config' is
exactly what 'base_vars' was, which is only the things being put into the env.
we weren't storing this field in the db, this doesn't break unless there are
messages in a queue from another version, anyway, don't think we're there and
don't expect any breakage for anybody with field name changes.
this makes the configuration stuff pretty straight forward, there's just two
separate buckets of things, and cold just needs to mash them together into the
env, and otherwise hot containers just need to put 'config' in the env, and then
hot format can shove 'headers' in however they'd like. this seems better than
my last idea about making this easier but worse (RIP).
this means:
* headers no longer contain all vars, the set of base vars can only be found
in the environment.
* headers is only the headers from request + call_id, deadline, method, url
* for cold, we simply add the headers to the environment, prepending
`FN_HEADER_` to them, BUT NOT upper casing or `s/-/_/`
* fixes issue where async hot functions would end up with `Fn_header_`
prefixed headers
* removes idea of 'base' vars and 'env'. this was a strange concept. now we just have
'config' which was base vars, and headers, which was base_env+headers; i.e.
they are disjoint now.
* casing for all headers will lean to be `My-Header` style, which should help
with consistency. notable exceptions for cold only are FN_CALL_ID, FN_METHOD,
and FN_REQUEST_URL -- this is simply to avoid breakage, in either hot format
they appear as `Fn_call_id` still.
* removes FN_PARAM stuff
* updated doc with behavior
weird things left:
`Fn_call_id` e.g. isn't a correctly formatted http header, it should likely be
`Fn-Call-Id` but I wanted to live to fight another day on this one, it would
add some breakage.
examples to be posted of each format below
closes#329
*) Updated fn-test-utils to latest fdk-go
*) Added hot-json to runner tests
*) Removed anon function in FromRequest which had
a side effect to set req.URL.Host. This is now more
explicit and eliminates some corresponding logic in
protocol http.
*) in gin, http request RequestURI is not set, removed
code that references this. (use Call.URL instead)
* route updated_at
* add app created at, fix some route updated_at bugs
* add app updated_at
TODO need to add tests through front end
TODO for validation we don't really want to use the validate wrapper since
it's a programmer error and not a user error, hopefully tests block this.
* add tests for timestamps to exist / change on apps&routes
* route equals at done, fix tests wit dis
* fix up the equals sugar
* add swagger
* fix rebase
* precisely allocate maps in clone
* vetted
* meh
* fix api tests
* wip
* wip
* Added more fields to JSON and added blank line between objects.
* Update tests.
* wip
* Updated to represent recent discussions.
* Fixed up the json test
* More docs
* Changed from blank line to bracket, newline, open bracket.
* Blank line added back, easier for delimiting.
this change makes Dispatch write request body and
http headers directly to pipe one by one
in case of non-empty request body,
if not - write headers and close finalize JSON
What's new?
- better error handling
- still need to decode JSON from function because we need status code and body
- prevent request body to be a problem by deferring its close
- moving examples around: putting http and json samples into one folder
* 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)
