third_party/repo: add TF_SYSTEM_LIBS to unbundle deps

Signed-off-by: Jason Zaman <jason@perfinion.com>

1 files changed, 32 insertions, 11 deletions

diff --git a/third_party/repo.bzl b/third_party/repo.bzl
index 9cee1fcc4b..fb33c389ac 100644
--- a/third_party/repo.bzl
+++ b/third_party/repo.bzl
@@ -35,6 +35,15 @@ def _get_env_var(ctx, name):
   else:
     return None
 
+# Checks if we should use the system lib instead of the bundled one
+def _use_system_lib(ctx, name):
+  syslibenv = _get_env_var(ctx, "TF_SYSTEM_LIBS")
+  if syslibenv:
+    for n in syslibenv.strip().split(","):
+      if n.strip() == name:
+        return True
+  return False
+
 # Executes specified command with arguments and calls 'fail' if it exited with
 # non-zero code
 def _execute_and_check_ret_code(repo_ctx, cmd_and_args):
@@ -75,17 +84,28 @@ def _tf_http_archive(ctx):
          "Even if you don't have permission to mirror the file, please " +
          "put the correctly formatted mirror URL there anyway, because " +
          "someone will come along shortly thereafter and mirror the file.")
-  ctx.download_and_extract(
-      ctx.attr.urls,
-      "",
-      ctx.attr.sha256,
-      ctx.attr.type,
-      ctx.attr.strip_prefix)
-  if ctx.attr.delete:
-    _apply_delete(ctx, ctx.attr.delete)
-  if ctx.attr.patch_file != None:
-    _apply_patch(ctx, ctx.attr.patch_file)
-  if ctx.attr.build_file != None:
+
+  use_syslib = _use_system_lib(ctx, ctx.attr.name)
+  if not use_syslib:
+    ctx.download_and_extract(
+        ctx.attr.urls,
+        "",
+        ctx.attr.sha256,
+        ctx.attr.type,
+        ctx.attr.strip_prefix)
+    if ctx.attr.delete:
+      _apply_delete(ctx, ctx.attr.delete)
+    if ctx.attr.patch_file != None:
+      _apply_patch(ctx, ctx.attr.patch_file)
+
+  if use_syslib and ctx.attr.system_build_file != None:
+    # Use BUILD.bazel to avoid conflict with third party projects with
+    # BUILD or build (directory) underneath.
+    ctx.template("BUILD.bazel", ctx.attr.system_build_file, {
+        "%prefix%": ".." if _repos_are_siblings() else "external",
+    }, False)
+
+  elif ctx.attr.build_file != None:
     # Use BUILD.bazel to avoid conflict with third party projects with
     # BUILD or build (directory) underneath.
     ctx.template("BUILD.bazel", ctx.attr.build_file, {
@@ -102,6 +122,7 @@ tf_http_archive = repository_rule(
         "delete": attr.string_list(),
         "patch_file": attr.label(),
         "build_file": attr.label(),
+        "system_build_file": attr.label(),
     })
 """Downloads and creates Bazel repos for dependencies.