This is an alternate way of solving the same problem as 4007a902a264e5ff2c3be6b269ade515c9c1c145,
but in a nicer way. Compared to using pointers, this approach more obviously preserves the original
behaviour, and is arguably more readable than the original code.
Credit to @rade for this approach.
Symptoms:
> app/control_router.go:44:38: error strings should not be capitalized or end with punctuation or a newline
This is blocking the build on:
https://circleci.com/gh/kinvolk/scope/363
gofmt load_container_filters.go
removed the environment variable for container label filters
Added the --app.container-label-filter command line argument, and load_container_filters.go now uses the results from that
Changed init() to InitializeTopologies()
Changed init() to InitializeTopologies() so that it can be called after the container filters are loaded from the command line argument. init() executes before main() in prog/main.go, so the flag parsing isn't finished before init() is called
Applied lint fixes
fixed lint issues
brought back the init function for api_topologies.go
Addressed many of the PR comments, except escaping colons
Renamed IsDesired to HasLabel in render/filters.go
Allows for the user to escape colons
added registry function for modifying the container filters
created a separate function that parses the container filter flags
simplified registry.addContainerFilters()
addressed review comments
switched API Topology Description IDs to constants
addressed review comments
joined constants
added test functions
addressed most of the review comments
Changed containerLabelFilters to an array of APItopologyOptions, placing the parsing in the Set() function. Removed parsing from HasLabel in render/filters.go
refactored code
added test that applies to the container filtering by labels
applied golint
made Registry items private and added a MakeRegistry() function
fixed usage of topologyRegistry.RendererForTopology
Added container label filters by exclusion
minor update to report_fixture
Modified container labels test to use existing report
I added labels to the existing containers in the fixed report for testing.
refactored code
refactored code
further code refactoring
addressed @ijsnellf's review comments
unexported Registry, and reduced duplicate code
addressed @ijsnellf's review comments
Addressed review comments
Addressed final review comments
Also:
- Parse targets on startup and catch badly formed ones before Scope can start.
- If no port is specified, use default port for scheme; if no scheme is specificed, use 4040.
- Use username as probe token
We fell victim to variable shadowing here. Each store would be fed the
original list of report keys, instead of only the ones that weren't
found in the previous store. So if a single report was missing from the
in-process cache, we would then fetch all reports from memcache. And if
that in turn was missing a single report we would fetch all reports from
S3.
We chain report stores for a reason - to reduce latency and, in case of
the in-process cache, eliminate decoding costs. So this bug has a huge
impact on query service performance.
To make matters worse, we return *all* the reports - now possibly in
triplicate. Fortunately, the SmartMerger filters these out, so at least
we were not incurring extra merge costs.
A lot of time could pass between recording the request count and hit
count pertaining to a particular report fetching batch, which skewed
calculations cache hit ratios.
Fix that by defering the request count recording to the end, which is
when we record the hit count.
Problem: Decoding a corrupt report grows the 'missing' list. Since we
are waiting for 'len(keys)-len(missing)' decoder go-routines, this
results in waiting for fewer go-routines than we should. The surplus
go-routines leak and we ignore their reports. And since the keys of the
ignored reports are not included in 'missing', we won't attempt to fetch
them from S3 either. Oops.
Fix: calculate the number of go-routines once, at the beginning.
The new probe will convert all node's LatestControls to Controls, so
the old app can consume them. Also, the new app will convert all
node's Controls to LatestControl, so it can consume the reports from
old probes.
