Cross compile docker script

[ethanfrey]

Closes #8

Dockerfile that builds linux and osx right now.
Details and README in the build directory.

@shanev can you please checkout this branch and validate that make test works out of the box (using my generated .dylib, not yours).

[shanev]

@ethanfrey This is the result of make test:

go test -v ./api
dyld: Library not loaded: /code/target/x86_64-apple-darwin/release/deps/libgo_cosmwasm.dylib
  Referenced from: /var/folders/jr/f46xqp790tl7sw7xlf3jjcg40000gn/T/go-build317794611/b001/api.test
  Reason: image not found
FAIL	github.com/confio/go-cosmwasm/api	0.003s
FAIL
make: *** [test] Error 1

[ethanfrey]

Remote debugging here:

https://stackoverflow.com/questions/17703510/dyld-library-not-loaded-reason-image-not-found

Please try:

otool -L ./api/libgo_cosmwasm.dylib

Maybe try setting DYLD_LIBRARY_PATH to point it to the proper location

[shanev]

After otool -L ./api/libgo_cosmwasm.dylib:

./api/libgo_cosmwasm.dylib:
	/code/target/x86_64-apple-darwin/release/deps/libgo_cosmwasm.dylib (compatibility version 0.0.0, current version 0.0.0)
	/usr/lib/libSystem.B.dylib (compatibility version 1.0.0, current version 1213.0.0)
	/usr/lib/libresolv.9.dylib (compatibility version 1.0.0, current version 1.0.0)

[ethanfrey]

@shanev I made another attempt here, maybe these work?
Can you check this out again and try make test and otool -L ./api/libgo_cosmwasm.dylib?

[shanev]

make test:

go test -v ./api
=== RUN   TestInitAndReleaseCache
thread '<unnamed>' panicked at 'called `Result::unwrap()` on an `Err` value: Os { code: 13, kind: PermissionDenied, message: "Permission denied" }', src/libcore/result.rs:1084:5
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace.
--- PASS: TestInitAndReleaseCache (0.00s)
    api_test.go:40: /var/folders/jr/f46xqp790tl7sw7xlf3jjcg40000gn/T/go-cosmwasm208121230
=== RUN   TestCreateAndGet
--- PASS: TestCreateAndGet (0.08s)
=== RUN   TestCreateFailsWithBadData
thread '<unnamed>' panicked at 'called `Result::unwrap()` on an `Err` value: ValidationError { msg: "Bad magic number" }', src/libcore/result.rs:1084:5
--- PASS: TestCreateFailsWithBadData (0.00s)
=== RUN   TestInstantiate
--- PASS: TestInstantiate (0.08s)
=== RUN   TestHandle
--- PASS: TestHandle (0.07s)
=== RUN   TestMultipleInstances
--- PASS: TestMultipleInstances (0.07s)
=== RUN   TestQueryFails
--- PASS: TestQueryFails (0.00s)
PASS
ok  	github.com/confio/go-cosmwasm/api	(cached)

otool -L ./api/libgo_cosmwasm.dylib:

./api/libgo_cosmwasm.dylib:
	/code/target/x86_64-apple-darwin/release/deps/libgo_cosmwasm.dylib (compatibility version 0.0.0, current version 0.0.0)
	/usr/lib/libSystem.B.dylib (compatibility version 1.0.0, current version 1213.0.0)
	/usr/lib/libresolv.9.dylib (compatibility version 1.0.0, current version 1.0.0)

[ethanfrey]

Looks like the otool output is the same.

make test is still using a cached test, doesn't rebuild on .dylib changes. You actually have to edit api.go and then run the tests again to ensure it will run the linkage step again (edit the file that declares linkage in the cgo header, not any other file).

Anyway, with the otool output, I will take it that nothing changed.

[ethanfrey]

With a bit of help, I discovered a solution to the problem, properly setting @rpath when compiling the libraries. I managed to get a valid build to work on an osx machine. But it needs some fixes, it leaves root files all over the target dir and breaks native cargo build on macos. Resolving these issues, then soon should have Dockerfied cross compilation, at least for linux and osx

[ethanfrey]

Validated to work on osx - both the cross-compile output and the native cargo build command.