This started as an attempt to placate GitHub's code scanner,
but it's also probably generally a good idea.
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
There are a few remaining uses of testing.AllocsPerRun:
Two in which we only log the number of allocations,
and one in which dynamically calculate the allocations
target based on a different AllocsPerRun run.
This also allows us to tighten the "no allocs"
test in wgengine/filter.
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
The code goes to some effort to send a single JSON object
when there's only a single line and a JSON array when there
are multiple lines.
It makes the code more complex and more expensive;
when we add a second line, we have to use a second buffer
to duplicate the first one after adding a leading square brackets.
The savings come to two bytes. Instead, always send an array.
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
+ add a test for parseAndRemoveLogLevel()
+ add a test for drainPendingMessages()
+ test JSON log encoding including several special cases
Other tests frequently send logs but a) don't check the result and
b) do so by happenstance, such that the code in encode() was not
consistently being exercised and leading to spurious changes in
code coverage. These tests attempt to more systematically test
the logging function.
This is the second attempt to add these tests, the first attempt
(in https://github.com/tailscale/tailscale/pull/1114) had two issues:
1. httptest.NewServer creates multiple goroutine handlers, and
logtail uses goroutines to upload, but the first version had no
locking in the server to guard this.
Moved data handling into channels to get synchronization.
2. The channel to notify the test of the arrival of data had a depth
of 1, in cases where the Logger sent multiple uploads it would
block the server.
This resulted in the first iteration of these tests being flaky,
and we reverted it.
This new version of the tests has passed with
go test -race -count=10000
and seems solid.
Signed-off-by: Denton Gentry <dgentry@tailscale.com>
This reverts commit e4f53e9b6f.
At least two of these tests are flakey, reverting until they can be
made more robust.
Signed-off-by: Denton Gentry <dgentry@tailscale.com>
* logtail: test parseAndRemoveLogLevel()
Signed-off-by: Denton Gentry <dgentry@tailscale.com>
* logtail: test JSON log encoding.
Expand TestUploadMessages to also exercise the encoding functions
in logtail, like JSON logging and timestamps.
Other tests frequently send logs but a) don't check the result and
b) do so by happenstance, such that the lines in encode() were not
consistently being exercised and leading to spurious changes in
code coverage.
Signed-off-by: Denton Gentry <dgentry@tailscale.com>
* logtail: add a test for drainPendingMessages
Make the client buffer some messages before the upload server
becomes available.
Signed-off-by: Denton Gentry <dgentry@tailscale.com>
* logtail: use %q, raw strings, and io.WriteString
%q escapes binary characters for us.
raw strings avoid so much backslash escaping
Signed-off-by: Denton Gentry <dgentry@tailscale.com>
Right now TestFastShutdown tries to upload logs to localhost:1234,
which will most likely respond with an error. However if one has an
actual service running on port 1234, it would receive a connection
attempting to POST every time the unit test runs.
Start a local server and direct the upload there instead.
Signed-off-by: Denton Gentry <dgentry@tailscale.com>
Start an HTTP server to accept POST requests, and upload some logs to
it. Check that uploaded logs were received.
Code in logtail:drainPending was not being reliably exercised by other
tests. This shows up in code coverage reports, as lines of code in
drainPending are alternately added and subtracted from code coverage.
This test will reliably exercise and verify this code.
Signed-off-by: Denton Gentry <dgentry@tailscale.com>
If a test calls log.Printf, 'go test' horrifyingly rearranges the
output to no longer be in chronological order, which makes debugging
virtually impossible. Let's stop that from happening by making
log.Printf panic if called from any module, no matter how deep, during
tests.
This required us to change the default error handler in at least one
http.Server, as well as plumbing a bunch of logf functions around,
especially in magicsock and wgengine, but also in logtail and backoff.
To add insult to injury, 'go test' also rearranges the output when a
parent test has multiple sub-tests (all the sub-test's t.Logf is always
printed after all the parent tests t.Logf), so we need to screw around
with a special Logf that can point at the "current" t (current_t.Logf)
in some places. Probably our entire way of using subtests is wrong,
since 'go test' would probably like to run them all in parallel if you
called t.Parallel(), but it definitely can't because the're all
manipulating the shared state created by the parent test. They should
probably all be separate toplevel tests instead, with common
setup/teardown logic. But that's a job for another time.
Signed-off-by: Avery Pennarun <apenwarr@tailscale.com>
