* actually disable stdout/stderr. stdout>stderr
* for pure runner this turns it off for real this time.
* this also just makes the agent container type send stdout to stderr, since
we're not using stdout for function output anymore this is pretty
straightforward hopefully.
* I added a panic and some type checking printlns to ensure this is true for
pure_runner, both stdout and stderr are off, also added a unit test from agent
to ensure this behavior from its container type, which pure_runner utilizes
(no integration test though)
* tests ensure that logs still work if not trying to disable them (full agent)
* handle non ghost swapping
* disable pure runner logging
there's a racey bug where the logger is being written to when it's closing,
but this led to figuring out that we don't need the logger at all in pure
runner really, the syslog thing isn't an in process fn thing and we don't need
the logs from attach for anything further in pure runner. so this disables the
logger at the docker level, to save sending the bytes back over the wire, this
could be a nice little performance bump too. of course, with this, it means
agents can be configured to not log debug or have logs to store at all, and
not a lot of guards have been put on this for 'full' agent mode while it hangs
on a cross feeling the breeze awaiting its demise - the default configuration
remains the same, and no behavior changes in 'full' agent are here.
it was a lot smoother to make the noop than to try to plumb in 'nil' for
stdout/stderr, this has a lot lower risk of nil panic issues for the same
effect, though it's not perfect relying on type casting, plumbing in an
interface to check has the same issues (loss of interface adherence for any
decorator), so this seems ok. defaulting to not having a logger was similarly
painful, and ended up with this. but open to ideas.
* replace usage of old null reader writer impl
* make Read return io.EOF for io.Copy usage
Now obsoleted driver.PrepareCookie() call handled image and
container creation. In agent, going forward we will need finer
grained control over the timeouts implied by the contexts.
For this reason, with this change, we split PrepareCookie()
into Validate/Pull/Create calls under Cookie interface.
Moving the timeout management of various docker operations
to agent. This allows for finer control over what operation
should use. For instance, for pause/unpause our tolerance
is very low to avoid resource issues. For docker remove,
the consequences of failure will lead to potential agent
failure and therefore we wait up to 10 minute.
For cookie create/prepare (which includes docker-pull)
we cap this at 10 minutes by default.
With new UDS/FDK contract, health check is now obsoleted
as container advertise health using UDS availibility.
* get rid of old format stuff, utils usage, fix up for fdk2.0 interface
* pure agent format removal, TODO remove format field, fix up all tests
* shitter's clogged
* fix agent tests
* start rolling through server tests
* tests compile, some failures
* remove json / content type detection on invoke/httptrigger, fix up tests
* remove hello, fixup system tests
the fucking status checker test just hangs and it's testing that it doesn't
work so the test passes but the test doesn't pass fuck life it's not worth it
* fix migration
* meh
* make dbhelper shut up about dbhelpers not being used
* move fail status at least into main thread, jfc
* fix status call to have FN_LISTENER
also turns off the stdout/stderr blocking between calls, because it's
impossible to debug without that (without syslog), now that stdout and stderr
go to the same place (either to host stderr or nowhere) and isn't used for
function output this shouldn't be a big fuss really
* remove stdin
* cleanup/remind: fixed bug where watcher would leak if container dies first
* silence system-test logs until fail, fix datastore tests
postgres does weird things with constraints when renaming tables, took the
easy way out
system-tests were loud as fuck and made you download a circleci text file of
the logs, made them only yell when they goof
* fix fdk-go dep for test image. fun
* fix swagger and remove test about format
* update all the gopkg files
* add back FN_FORMAT for fdks that assert things. pfft
* add useful error for functions that exit
this error is really confounding because containers can exit for all manner of
reason, we're just guessing that this is the most likely cause for now, and
this error message should very likely change or be removed from the client
path anyway (context.Canceled wasn't all that useful either, but anyway, I'd
been hunting for this... so found it). added a test to avoid being publicly
shamed for 1 line commits (beware...).
Streaming docker events is useful as we can record/capture some
asynchronous containers events such as out-of-memory. For now,
we record these in opencensus/prometheus stats.
* Define an interface for IOFS handling. Add no-op and temporary directory implementations.
* Move IOFS stuff out into separate file, add basic tmpfs implementation for linux only
* Switch between directory and tmpfs based on platform and config
* Respect FN_IOFS_OPTS
* Make directory iofs default on all platforms
* At least try to clean up a bit on failure
* Add backout if IOFS creation fails
* Add comment about iofs.Close
Largely a removal job, however many tests, particularly system level
ones relied on Routes. These have been migrated to use Fns.
* Add 410 response to swagger
* No app names in log tags
* Adding constraint in GetCall for FnID
* Adding test to check FnID is required on call
* Add fn_id to call selector
* Fix text in docker mem warning
* Correct buildConfig func name
* Test fix up
* Removing CPU setting from Agent test
CPU setting has been deprecated, but the code base is still riddled
with it. This just removes it from this layer. Really we need to
remove it from Call.
* Remove fn id check on calls
* Reintroduce fn id required on call
* Adding fnID to calls for execute test
* Correct setting of app id in middleware
* Removes root middlewares ability to redirect fun invocations
* Add over sized test check
* Removing call fn id check
* POC code for inotify UDS-io-socket
* http-stream format
introducing the `http-stream` format support in fn. there are many details for
this, none of which can be linked from github :( -- docs are coming (I could
even try to add some here?). this is kinda MVP-ish level, but does not
implement the remaining spec, ie 'headers' fixing up / invoke fixing up. the
thinking being we can land this to test fdks / cli with and start splitting
work up on top of this. all other formats work the same as previous (no
breakage, only new stuff)
with the cli you can set `format: http-stream` and deploy, and then invoke a
function via the `http-stream` format. this uses unix domain socket (uds) on
the container instead of previous stdin/stdout, and fdks will have to support
this in a new fashion (will see about getting docs on here). fdk-go works,
which is here: https://github.com/fnproject/fdk-go/pull/30 . the output looks
the same as an http format function when invoking a function. wahoo.
there's some amount of stuff we can clean up here, enumerated:
* the cleanup of the sock files is iffy, high pri here
* permissions are a pain in the ass and i punted on dealing with them. you can
run `sudo ./fnserver` if running locally, it may/may not work in dind(?) ootb
* no pipe usage at all (yay), still could reduce buffer usage around the pipe
behavior, we could clean this up potentially before removal (and tests)
* my brain can’t figure out if dispatchOldFormats changes pipe behavior, but
tests work
* i marked XXX to do some clean up which will follow soon… need this to test fdk
tho so meh, any thoughts on those marked would be appreciated however (1 less
decision for me). mostly happy w/ general shape/plumbing tho
* there are no tests atm, this is a tricky dance indeed. attempts were made.
need to futz with the permission stuff before committing to adding any tests
here, which I don't like either. also, need to get the fdk-go based test image
updated according to the fdk-go, and there's a dance there too. rumba time..
* delaying the big big cleanup until we have good enough fdk support to kill
all the other formats.
open to ideas on how to maneuver landing stuff...
* fix unmount
* see if the tests work on ci...
* add call id header
* fix up makefile
* add configurable iofs opts
* add format file describing http-stream contract
* rm some cruft
* default iofs to /tmp, remove mounting
out of the box fn we can't mount. /tmp will provide a memory backed fs for us
on most systems, this will be fine for local developing and this can be
configured to be wherever for anyone that wants to make things more difficult
for themselves.
also removes the mounting, this has to be done as root. we can't do this in
the oss fn (short of requesting root, but no). in the future, we may want to
have a knob here to have a function that can be configured in fn that allows
further configuration here. since we don't know what we need in this dept
really, not doing that yet (it may be the case that it could be done
operationally outside of fn, eg, but not if each directory needs to be
configured itself, which seems likely, anyway...)
* add WIP note just in case...
* fn: check context timeout when waiting for non-blocking attach
With this change, we no longer allow docker client AttachToContainerNonBlocking
to block on Success channel more than our context deadline/timeout.
* fn: move nbio chan handling in attach to docker from docker-client
fixes#1101
additional context:
* this was introduced in docker 1.13 (1/2017), we require docker 17.10
(10/2017), this should not have any issues dependency-wise, as `docker-init`
is in the docker install from that point in time. unless explicitly removed,
it should be in the dind container we use as well...
* the PR that introduced this to docker is
https://github.com/moby/moby/pull/26061 for additional context
* it may be wise to put this through some paces, if anybody has any...
interesting... function containers. the tests seem to work fine, however, and
this shouldn't be something users have to think about (?) at all, just
something that we are doing. this isn't the default in docker for
compatibility reasons, which is maybe a yellow flag but I am not sure tbh
* fn: introducing docker-syslog driver as default logger
With this change, fn-agent prefers RFC2454 docker-syslog driver
for logging stdout/stderr from containers. The advantage
of this is to offload it to docker itself instead of
streaming stderr along with stdout, which gets multiplexed
through single connection via docker-API.
The change will need support from FDKs in order to log
correct call-id and supress '\n' that splits syslog lines.
* fn: cleanup of docker private registry code
Start using URL parsed ServerAddress and its subdomains
for easier image ensure/pull in docker driver. Previous
code to lookup substrings was faulty without proper
URL parse and hostname tokenization. When searching
for a registry config, if image name does not contain
a registry and if there's a private registry configured,
then search for hub.docker.com and index.docker.io. This
is similar to previous code but with correct subdomain
matching.
* fn-dataplane: take port into account in auth configs
* fn: runner status and docker load images
Introducing a function run for pure runner Status
calls. Previously, Status gRPC calls returned active
inflight request counts with the purpose of a simple
health checker. However this is not sufficient since
it does not show if agent or docker is healthy. With
this change, if pure runner is configured with a status
image, that image is executed through docker. The
call uses zero memory/cpu/tmpsize settings to ensure
resource tracker does not block it.
However, operators might not always have a docker
repository accessible/available for status image. Or
operators might not want the status to go over the
network. To allow such cases, and in general possibly
caching docker images, added a new environment variable
FN_DOCKER_LOAD_FILE. If this is set, fn-agent during
startup will load these images that were previously
saved with 'docker save' into docker.
* add DateTime sans mgo
* change all uses of strfmt.DateTime to common.DateTime, remove test strfmt usage
* remove api tests, system-test dep on api test
multiple reasons to remove the api tests:
* awkward dependency with fn_go meant generating bindings on a branched fn to
vendor those to test new stuff. this is at a minimum not at all intuitive,
worth it, nor a fun way to spend the finite amount of time we have to live.
* api tests only tested a subset of functionality that the server/ api tests
already test, and we risk having tests where one tests some thing and the
other doesn't. let's not. we have too many test suites as it is, and these
pretty much only test that we updated the fn_go bindings, which is actually a
hassle as noted above and the cli will pretty quickly figure out anyway.
* fn_go relies on openapi, which relies on mgo, which is deprecated and we'd
like to remove as a dependency. openapi is a _huge_ dep built in a NIH
fashion, that cannot simply remove the mgo dep as users may be using it.
we've now stolen their date time and otherwise killed usage of it in fn core,
for fn_go it still exists but that's less of a problem.
* update deps
removals:
* easyjson
* mgo
* go-openapi
* mapstructure
* fn_go
* purell
* go-validator
also, had to lock docker. we shouldn't use docker on master anyway, they
strongly advise against that. had no luck with latest version rev, so i locked
it to what we were using before. until next time.
the rest is just playing dep roulette, those end up removing a ton tho
* fix exec test to work
* account for john le cache
In pure-runner and LB agent, service providers might want to set specific driver options.
For example, to add cpu-shares to functions, LB can add the information as extensions
to the Call and pass this via gRPC to runners. Runners then pick these extensions from
gRPC call and pass it to driver. Using a custom driver implementation, pure-runners can
process these extensions to modify docker.CreateContainerOptions.
To achieve this, LB agents can now be configured using a call overrider.
Pure-runners can be configured using a custom docker driver.
RunnerCall and Call interfaces both expose call extensions.
An example to demonstrate this is implemented in test/fn-system-tests/system_test.go
which registers a call overrider for LB agent as well as a simple custom docker driver.
In this example, LB agent adds a key-value to extensions and runners add this key-value
as an environment variable to the container.
When TmpFsSize is not set in a route, docker fails to create a /tmp
mount that is writable. Forcing docker to explicitly to this if
read-only root directory is enabled (default).
* fn: size restricted tmpfs /tmp and read-only / support
*) read-only Root Fs Support
*) removed CPUShares from docker API. This was unused.
*) docker.Prepare() refactoring
*) added docker.configureTmpFs() for size limited tmpfs on /tmp
*) tmpfs size support in routes and resource tracker
*) fix fn-test-utils to handle sparse files better in create file
* test typo fix
* fn: allow specified docker networks in functions
If FN_DOCKER_NETWORK is specified with a list of
networks, then agent driver picks the least used
network to place functions on.
* add mutex comment
* fn: experimental prefork recycle and other improvements
*) Recycle and do not use same pool container again option.
*) Two state processing: initializing versus ready (start-kill).
*) Ready state is exempt from rate limiter.
* fn: experimental prefork pool multiple network support
In order to exceed 1023 container (bridge port) limit, add
multiple networks:
for i in fn-net1 fn-net2 fn-net3 fn-net4
do
docker network create $i
done
to Docker startup, (eg. dind preentry.sh), then provide this
to prefork pool using:
export FN_EXPERIMENTAL_PREFORK_NETWORKS="fn-net1 fn-net2 fn-net3 fn-net4"
which should be able to spawn 1023 * 4 containers.
* fn: fixup tests for cfg move
* fn: add ipc and pid namespaces into prefork pooling
* fn: revert ipc and pid namespaces for now
Pid/Ipc opens up the function container to pause container.
Added env FN_MAX_FS_SIZE_MB, which if defined and non-zero
is passed to docker as storage opt size. We do not validate
if this option is supported by docker currently. This is
because it's difficult to actually validate this since it
not only depends on storage driver and its backing filesystem,
but also the mount options used to mount that fs.
* fn: enable failing test back
* fn: fortifying the stderr output
Modified limitWriter to discard excess data instead
of returning error, this is to allow stderr/stdout
pipes flowing to avoid head-of-line blocking or
data corruption in container stdout/stderr output stream.
*) I/O protocol parse issues should shutdown the container as the container
goes to inconsistent state between calls. (eg. next call may receive previous
calls left overs.)
*) Move ghost read/write code into io_utils in common.
*) Clean unused error from docker Wait()
*) We can catch one case in JSON, if there's remaining unparsed data in
decoder buffer, we can shut the container
*) stdout/stderr when container is not handling a request are now blocked if freezer is also enabled.
*) if a fatal err is set for slot, we do not requeue it and proceed to shutdown
*) added a test function for a few cases with freezer strict behavior
* update vendor directory, add go.opencensus.io
* update imports
* oops
* s/opentracing/opencensus/ & remove prometheus / zipkin stuff & remove old stats
* the dep train rides again
* fix gin build
* deps from last guy
* start in on the agent metrics
* she builds
* remove tags for now, cardinality error is fussing. subscribe instead of register
* update to patched version of opencensus to proceed for now TODO switch to a release
* meh
fix imports
* println debug the bad boys
* lace it with the tags
* update deps again
* fix all inconsistent cardinality errors
* add our own logger
* fix init
* fix oom measure
* remove bugged removal code
* fix s3 measures
* fix prom handler nil
we have been getting these from attach all this time and never needed these
anyway.
I ran cpu profiles of dockerd and this was 90% of docker cpu usage (json
logs). woot. this will reduce i/o quite a bit, and we don't have to worry
about them taking up any disk space either.
from tests i get about 50% speedup with these off. the hunt continues...
closes#317
we could fiddle with this, but we need to at least bound these. this
accomplishes that. 1m is picked since that's our default max log size for the
time being per call, it also takes a little time to generate that many bytes
through logs, typically (i.e. without trying to). I tested with 0, which
spiked the i/o rate on my machine because it's constantly deleting the json
log file. I also tested with 1k and it was similar (for a task that generated
about 1k in logs quickly) -- in testing, this halved my throughput, whereas
using 1m did not change the throughput at all. trying the 'none' driver and
'syslog' driver weren't great, 'none' turns off all stderr and 'syslog' blocks
every log line (boo). anyway, this option seems to have no affect on the
output we get in 'attach', which is what we really care about (i.e. docker is
not logically capping this, just swapping out the log file).
using 1m for this, e.g. if we have 500 hot containers on a machine we have
potentially half a gig of worthless logs laying around. we don't need the
docker logs laying around at all really, but short of writing a storage driver
ourselves there don't seem to be too many better options. open to idears, but
this is likely to hold us over for some time.
* add per call stats field as histogram
this will add a histogram of up to 240 data points of call data, produced
every second, stored at the end of a call invocation in the db. the same
metrics are also still shipped to prometheus (prometheus has the
not-potentially-reduced version). for the API reference, see the updates to
the swagger spec, this is just added onto the get call endpoint.
this does not add any extra db calls and the field for stats in call is a json
blob, which is easily modified to add / omit future fields. this is just
tacked on to the call we're making to InsertCall, and expect this to add very
little overhead; we are bounding the set to be relatively small, planning to
clean out the db of calls periodically, functions will generally be short, and
the same code used at a previous firm did not cause a notable db size increase
with production workload that is worse, wrt histogram size (I checked). the
code changes are really small aside from changing to strfmt.DateTime,
adding a migration and implementing sql.Valuer; needed to slightly modify the
swap function so that we can safely read `call.Stats` field to upload at end.
with the full histogram in hand, we can compute max/min/average/median/growth
rate/bernoulli distributions/whatever very easily in a UI or tooling. in
particular, this data is easily chartable [for a UI], which is beneficial.
* adds swagger spec of api update to calls endpoint
* adds migration for call.stats field
* adds call.stats field to sql queries
* change swapping of hot logger to exec, so we know that call.Stats is no
longer being modified after `exec` [in call.End]
* throws out docker stats between function invocations in hot functions (no
call to store them on, we could change this later for debug; they're in prom)
* tested in tests and API
closes#19
* add format of ints to swag
before returning the cookie in the driver, wait for health checks
https://docs.docker.com/engine/reference/builder/#healthcheck if provided.
for images that don't have health checks, this will have no affect (an added
call to inspect container, for hot it's small potatoes).
this will be useful for containers so that they can pull large files or do
setup that takes a while before accepting tasks. since this is before start,
it won't run into the idle timeout. we could likely use these for hot
containers in general and check between runs or something, but didn't do that
here.
one nascient concern is that for hot if the containers never become healthy
I don't think we will ever kill them and the slot will 'leak'. this is true
for this and for other cases (pulling image) I think, we should probably
recycle hot containers every hour or something which would also close this.
anyway, not a huge blocker I don't think, there will likely be 1 user of this
feature for a bit, it's not documented since we're not sure we want to support
it.
closes#336
* Docker stats to Prometheus
* Fix compilation error in docker_test
* Refactor docker driver Run function to wait for the container to have stopped before stopping the colleciton of statistics
* Fix go fmt errors
* Updates to sending docker stats to Prometheus
* remove new test TestWritResultImpl because we changes to support multiple waiters have been removed
* Update docker.Run to use channels not contextrs to shut down stats collector
currently:
* container ran out of memory (code 137)
* container exited with other code != 0
* unable to pull image (auth/404)
there may be others but this is a good start (the most common). notably, for
both hot and cold these should bubble up (if deterministic, which hub isn't
always), and these are useful for users to use in debugging why things aren't
working.
added tests to make sure that these behaviors are working.
also changed the behavior such that when the container exits we return a 502
instead of a 503, just to be able to distinguish the fact that fn is working
as expected but the container is acting funky (400 is weird here, so idk).
removed references to old IsUserVisible crap and slightly changed the
interface for RunResult for plumbing reasons (to get the error type,
specifically).
fixed an issue where if ~/.docker/config.json exists sometimes pulling images
wouldn't work deterministically (should be more inline w/ expectations now)
closes#275
* 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)
