Better build instructions, please

[Nuru]

I was trying to make a pretty simple PR, just change a tiny bit of HTML and CSS, but building Atlantis proved challenging. I am new to go and its build requirements, but even accounting for that I think it was harder than it needed to be.

First of all, despite the comprehensive documentation on how to run and test Atlantis locally, I could find nothing about how to build it locally. So I tried using make, but ran into lots of problems (output edited for brevity, go 1.12.7 installed):

$ make build-service
CGO_ENABLED=0 GOOS=linux GOARCH=amd64 go build -mod=vendor -v -o atlantis .
build flag -mod=vendor only valid when using modules
make: *** [build-service] Error 1

$ make dist
/bin/sh: go-bindata-assetfs: command not found
make: *** [dist] Error 127

$ go get github.com/elazarl/go-bindata-assetfs/...
$ make dist
/bin/sh: go-bindata-assetfs: command not found
make: *** [dist] Error 127

$ export PATH=$GOPATH/bin:$PATH
$ make dist
rm -f server/static/bindata_assetfs.go && go-bindata-assetfs -pkg static -prefix server server/static/... && mv bindata_assetfs.go server/static
mv: rename bindata_assetfs.go to server/static/bindata_assetfs.go: No such file or directory
make: *** [dist] Error 1

$ make release
...
Packaging...
find: ./output: No such file or directory

$ mkdir output
$ make release
...
./scripts/binary-release.sh
-> running clean up....
-> building...
Error reading packages: exit status 1
Stderr: go: downloading github.com/google/go-github/v28 v28.0.0
...

Packaging...


-----------------------------------
Output:
total 0
drwxr-xr-x   2 user  admin    68B Sep 20 02:12 .
drwxr-xr-x  31 user  admin   1.0K Sep 20 02:12 ..

$ make build-service
CGO_ENABLED=0 GOOS=linux GOARCH=amd64 go build -mod=vendor -v -o atlantis .
build github.com/runatlantis/atlantis: cannot load github.com/runatlantis/atlantis/server/static: no Go source files

$ mv bindata.go server/static/bindata_assetfs.go
$ make build-service
CGO_ENABLED=0 GOOS=linux GOARCH=amd64 go build -mod=vendor -v -o atlantis .
build flag -mod=vendor only valid when using modules
make: *** [build-service] Error 1

$ make release
./scripts/binary-release.sh
-> running clean up....
-> building...
Number of parallel builds: 7

-->       linux/386: github.com/runatlantis/atlantis
-->     linux/amd64: github.com/runatlantis/atlantis
-->    darwin/amd64: github.com/runatlantis/atlantis
-->       linux/arm: github.com/runatlantis/atlantis

Packaging...
--> darwin_amd64
  adding: atlantis (deflated 59%)
--> linux_386
  adding: atlantis (deflated 55%)
--> linux_amd64
  adding: atlantis (deflated 59%)
--> linux_arm
  adding: atlantis (deflated 56%)


-----------------------------------
Output:
total 106752
drwxr-xr-x  10 user  admin   340B Sep 20 02:40 .
drwxr-xr-x  31 user  admin   1.0K Sep 20 02:32 ..
-rw-r--r--   1 user  admin    13M Sep 20 02:40 atlantis_darwin_amd64.zip
-rw-r--r--   1 user  admin    13M Sep 20 02:40 atlantis_linux_386.zip
-rw-r--r--   1 user  admin    13M Sep 20 02:40 atlantis_linux_amd64.zip
-rw-r--r--   1 user  admin    12M Sep 20 02:40 atlantis_linux_arm.zip
drwxr-xr-x   3 user  admin   102B Sep 20 02:40 darwin_amd64
drwxr-xr-x   3 user  admin   102B Sep 20 02:40 linux_386
drwxr-xr-x   3 user  admin   102B Sep 20 02:40 linux_amd64
drwxr-xr-x   3 user  admin   102B Sep 20 02:40 linux_arm

So at the very least, the build of bindata_assetfs.go needs to be fixed.

Ideally, the release target would depend on the needed artifacts and automatically build them. Also the build-service target should work to build a local version for dev/test.

[jamengual]

Closed due to inactivity, if this still needed comment and we will reopen but check the latest docs/features first.
Thanks.