The `linkerd install` output relies on Helm templates in the `chart`
directory. In production cli builds, these templates are compiled into
the binary. In development, they are read from the file system. This
development code path relied on GOPATH to determine the location of the
`chart` directory. In anticipation of Go Modules support (#1488), we
cannot assume the repo is within the GOPATH.
This change removes the GOPATH dependency, and instead relies on
`runtime.Caller` to determine the root of the code repo. This change
only affects development (!prod) builds.
Prerequisite to #1488.
Signed-off-by: Andrew Seigner <siggy@buoyant.io>
# Problem
In order to switch Linkerd template rendering to use `.yaml` files, static
assets must be bundled in the Go binary for use by `linkerd install`.
# Solution
The solution should not affect the local development process of building and
testing.
[vfsgen](https://github.com/shurcooL/vfsgen) generates Go code that statically
implements the provided `http.FileSystem`. Paired with `go generate` and Go
[build tags](https://golang.org/pkg/go/build/), we can continue to use the
template files on disk when developing with no change required.
In `!prod` Go builds, the `cli/static/templates.go` file provides a
`http.FileSystem` to the local templates. In `prod` Go builds, `go generate
./cli` generates `cli/static/generated_templates.gogen.go` that statically
provides the template files.
When built with `-tags prod`, the executable will be built with the staticlly
generated file instead of the local files.
# Validation
The binaries were compiled locally with `bin/docker-build`. The binaries were
then tested with `bin/test-run (pwd)/target/cli/darwin/linkerd`. All tests
passed.
No change was required to successfully run `bin/go-run cli install`. No change
was required to run `bin/linkerd install`.
Fixes#2153
Signed-off-by: Kevin Leimkuhler <kevin@kleimkuhler.com>
Andrew Seigner
Alejandro Pedraza
Kevin Leimkuhler