* move calls to logstore, implement s3
closes#482
the basic motivation is that logs and calls will be stored with a very high
write rate, while apps and routes will be relatively infrequently updated; it
follows that we should likely split up their storage location, to back them
with appropriate storage facilities. s3 is a good candidate for ingesting
higher write rate data than a sql database, and will make it easier to manage
that data set. can read #482 for more detailed justification.
summary:
* calls api moved from datastore to logstore
* logstore used in front-end to serve calls endpoints
* agent now throws calls into logstore instead of datastore
* s3 implementation of calls api for logstore
* s3 logs key changed (nobody using / nbd?)
* removed UpdateCall api (not in use)
* moved call tests from datastore to logstore tests
* mock logstore now tested (prev. sqlite3 only)
* logstore tests run against every datastore (mysql, pg; prev. only sqlite3)
* simplify NewMock in tests
commentary:
brunt of the work is implementing the listing of calls in GetCalls for the s3
logstore implementation. the GetCalls API requires returning items in the
newest to oldest order, and the s3 api lists items in lexicographic order
based on created_at. An easy thing to do here seemed to be to reverse the
encoding of our id format to return a lexicographically descending order,
since ids are time based, reasonably encoded to be lexicographically
sortable, and de-duped (unlike created_at). This seems to work pretty well,
it's not perfect around the boundaries of to_time and from_time and a tiny
amount of results may be omitted, but to me this doesn't seem like a deal
breaker to get 6999 results instead of 7000 when trying to get calls between
3:00pm and 4:00pm Monday 3 weeks ago. Of course, without to_time and
from_time, there are no issues in listing results. We could use created at and
encode it, but it would be an additional marker for point lookup (GetCall)
since we would have to search for a created_at stamp, search for ids around
that until we find the matching one, just to do a point lookup. So, the
tradeoff here seems worth it. There is additional optimization around to_time
to seek over newer results (since we have descending order).
The other complication in GetCalls is returning a list of calls for a given
path. Since the keys to do point lookups are only app_id + call_id, and we
need listing across an app as well, this leads us to the 'marker' collection
which is sorted by app_id + path + call_id, to allow quick listing by path.
All in all, it should be pretty straightforward to follow the implementation
and I tried to be lavish with the comments, please let me know if anything
needs further clarification in the code.
The implementation itself has some glaring inefficiencies, but they're
relatively minute: json encoding is kinda lazy, but workable; s3 doesn't offer
batch retrieval, so we point look up each call one by one in get call; not
re-using buffers -- but the seeking around the keys should all be relatively
fast, not too worried about performance really and this isn't a hot path for
reads (need to make a cut point and turn this in!).
Interestingly, in testing, minio performs significantly worse than pg for
storing both logs and calls (or just logs, I tested that too). minio seems to
have really high cpu consumption, but in any event, we won't be using minio,
we'll be using a cloud object store that implements the s3 api. Anyway, mostly
a knock on using minio for high performance, not really anything to do with
this, just thought it was interesting.
I think it's safe to remove UpdateCall, admittedly this made implementing the
s3 api a lot easier. This operation may also be something we never need, it
was unused at present and was only in the cards for a previous hybrid
implementation, which we've now abandoned. If we need, we can always resurrect
from git.
Also not worried about changing the log key, we need to put a prefix on this
thing anyway, but I don't think anybody is using this anyway. in any event, it
simply means old logs won't show up through the API, but aside from nobody
using this yet, that doesn't seem a big deal breaker really -- new logs will
appear fine.
future:
TODO make logstore implementation optional for datastore, check in front-end
at runtime and offer a nil logstore that errors appropriately
TODO low hanging fruit optimizations of json encoding, re-using buffers for
download, get multiple calls at a time, id reverse encoding could be optimized
like normal encoding to not be n^2
TODO api for range removal of logs and calls
* address review comments
* push id to_time magic into id package
* add note about s3 key sizes
* fix validation check
Oracle Linux 7.4 backported versions still having issues
with freezing/terminating containers. 17.10.0-ce seems like
a resonable lowest common denominator.
when the annotations change, we need to get a different slot key to launch new
containers with these annotations and let the old containers die off unused.
I started on a test for this, but changing all combinations of each field in
isolation to change is not very fun without reflection, and there's still a
subset of fields we're managing, so it put us in about the same spot as we are
now.
There are alternative formulations of this, for instance see
https://www.reddit.com/r/golang/comments/5zctpf/unsafe_conversion_between_strings_and_byte_slices/
The problem manifested in the returned values from unsafeBytes occasionally
being broken. It's possible that by keeping a reference to the `a` parameter
alive, the original code would still work - however, this definitely seems like
a fix.
(A cast to `[]byte(a)` looks increasingly attractive, for all that it'll
perform small allocations and copies.)
* GRPC streams end with an EOF
The client should ensure that the final packet is followed by a GRPC
EOF. This has the benefit of permitting the client code to clean up resources.
* Don't require an entire HTTP request in RunnerCall
TryExec needs a handle on an incoming ReadCloser containing the body
of a request; however, everything else will already have been extracted
from the HTTP request in the case of lbAgent use.
(The point of this change is to simplify the interface for other uses.)
* Return error from GRPC layer explicitly
As per review
pureRunner is a not exported struct and it was set as return value for
few exported method, in this change we return Agent which is the
interface implemented by pureRunner to avoid to leak an unexprted type.
In one of the test we want a failure due to a 500 error returned by a
not existing local registry, the fake server address is set to localhost:5000
In a typical local env is quite likely to have a local registry running
and the default address usually is localhost:5000 and that will make the
test to return a 4xx error and not the expected 500 error, this change
just set a not standard port for the fake local registry to reduce the
chances to clash with an existing running one.
* support runner TLS certificates with specified certificate Common Names
* removes duplicate constant
* run in insecure mode by default but expose ability to create tls-secured runner pools programmatically
* fixes runner tests to use new tls interfaces
* App ID
* Clean-up
* Use ID or name to reference apps
* Can use app by name or ID
* Get rid of AppName for routes API and model
routes API is completely backwards-compatible
routes API accepts both app ID and name
* Get rid of AppName from calls API and model
* Fixing tests
* Get rid of AppName from logs API and model
* Restrict API to work with app names only
* Addressing review comments
* Fix for hybrid mode
* Fix rebase problems
* Addressing review comments
* Addressing review comments pt.2
* Fixing test issue
* Addressing review comments pt.3
* Updated docstring
* Adjust UpdateApp SQL implementation to work with app IDs instead of names
* Fixing tests
* fmt after rebase
* Make tests green again!
* Use GetAppByID wherever it is necessary
- adding new v2 endpoints to keep hybrid api/runner mode working
- extract CallBase from Call object to expose that to a user
(it doesn't include any app reference, as we do for all other API objects)
* Get rid of GetAppByName
* Adjusting server router setup
* Make hybrid work again
* Fix datastore tests
* Fixing tests
* Do not ignore app_id
* Resolve issues after rebase
* Updating test to make it work as it was
* Tabula rasa for migrations
* Adding calls API test
- we need to ensure we give "App not found" for the missing app and missing call in first place
- making previous test work (request missing call for the existing app)
* Make datastore tests work fine with correctly applied migrations
* Make CallFunction middleware work again
had to adjust its implementation to set app ID before proceeding
* The biggest rebase ever made
* Fix 8's migration
* Fix tests
* Fix hybrid client
* Fix tests problem
* Increment app ID migration version
* Fixing TestAppUpdate
* Fix rebase issues
* Addressing review comments
* Renew vendor
* Updated swagger doc per recommendations
another bone head fail here. hopefully can leave this alone meow...
newID does not get inlined, but doesn't allocate to trigger any stack
expansion either. net perf hit on my laptop is 5ns, and we get a test out of
it. it will push a new stack, so it's not negligible overhead and we could
avoid it. we could keep the logic in both places just to have a test for it
separate instead of re-using the function in the hot path. up to us.
the error itself from up/down & dirty can be improved to show direction and
version information to help a user of the package determine where things went
wrong, which is useful when a series of migrations are run and the db error
itself is not clear about what went wrong exactly.
* Move delegated agent creation within NewLBAgent so we can hide the fact we disable docker
* Move delegated agent creation within NewPureRunner for better encapsulation