commit 73e56605000ac366290798891bcea54d8535767f
author Philipp Schrader <philipp.schrader@gmail.com> Mon Dec 06 21:37:30 2021 -0800
committer Philipp Schrader <philipp.schrader@gmail.com> Wed Dec 08 21:52:01 2021 -0800
tree 180a79a684da262293b8c3739f74a699dd6d55b5
parent 4665195800520ab2bcb40b6ed5edac6171f3e3b3

Import rules_go

The motivation here is to use Go for the scouting web server. It
sounds like we have enough knowledge in the team to at least give it a
try.

    $ bazel run //build_tests:hello_go
    WARNING: Option 'ui' is deprecated
    INFO: Invocation ID: d227f296-c249-44d3-88c0-42c2aee1bde2
    INFO: SHA256 (https://golang.org/dl/?mode=json&include=all) = dd71d0c702dbeb9a765da037c9792250fb9e440fa3bd5dbdca91db34f0265446
    INFO: Analyzed target //build_tests:hello_go (45 packages loaded, 47836 targets configured).
    INFO: Found 1 target...
    INFO: Writing explanation of rebuilds to '/tmp/bazel_explain.log'
    Target //build_tests:hello_go up-to-date:
      bazel-bin/build_tests/hello_go_/hello_go
    INFO: Elapsed time: 99.935s, Critical Path: 1.57s
    INFO: 8 processes: 4 internal, 4 linux-sandbox.
    INFO: Build completed successfully, 8 total actions
    INFO: Build completed successfully, 8 total actions
    hello world

In order to work around a bazel issue, I created a dummy NOOP Go
toolchain. That toolchain will be used on all platforms where we don't
explicitly support Go. The key is to also mark all `go_*` target as
only being compatible with x86 Linux.

Change-Id: I0a9be3748c59998f5d2dea8d6a162779a0f31af1
Signed-off-by: Philipp Schrader <philipp.schrader@gmail.com>

tools/platforms/BUILD

diff --git a/tools/platforms/BUILD b/tools/platforms/BUILD
index 65563bf..4aa3db3 100644
--- a/tools/platforms/BUILD
+++ b/tools/platforms/BUILD
@@ -5,6 +5,7 @@
     constraint_values = [
         "@platforms//os:linux",
         "@platforms//cpu:x86_64",
+        "//tools/platforms/go:has_support",
     ],
 )
 
@@ -14,6 +15,7 @@
         "@platforms//os:linux",
         "@platforms//cpu:armv7",
         "//tools/platforms/hardware:raspberry_pi",
+        "//tools/platforms/go:lacks_support",
     ],
 )
 
@@ -22,6 +24,7 @@
     constraint_values = [
         "@platforms//os:linux",
         "@platforms//cpu:arm64",
+        "//tools/platforms/go:lacks_support",
     ],
 )
 
@@ -31,6 +34,7 @@
         "@platforms//os:linux",
         "@platforms//cpu:armv7",
         "//tools/platforms/hardware:roborio",
+        "//tools/platforms/go:lacks_support",
     ],
 )
 
@@ -39,6 +43,7 @@
     constraint_values = [
         "@platforms//os:none",
         "//tools/platforms/hardware:cortex_m4f",
+        "//tools/platforms/go:lacks_support",
     ],
 )
 

tools/platforms/go/BUILD

diff --git a/tools/platforms/go/BUILD b/tools/platforms/go/BUILD
new file mode 100644
index 0000000..5936287
--- /dev/null
+++ b/tools/platforms/go/BUILD
@@ -0,0 +1,13 @@
+package(default_visibility = ["//visibility:public"])
+
+constraint_setting(name = "go_support")
+
+constraint_value(
+    name = "has_support",
+    constraint_setting = ":go_support",
+)
+
+constraint_value(
+    name = "lacks_support",
+    constraint_setting = ":go_support",
+)