Merge branch 'levsha/IDX-2857-wait-for-the-artifact-to-be-published-' into 'master'

IDX-2857: wait for the artifact to be published.

Check that the artifact is in the bazel cache and only finish and return
url when it is there.
This will avoid races and still allow to work with bazel cache in async
mode. 

See merge request dfinity-lab/public/ic!12567

Author: marko-k0

bazel/BUILD.bazel

@@ -136,3 +136,9 @@ version_file_path(
     name = "version_file_path",
     visibility = ["//rs/tests:__subpackages__"],
 )
+
+sh_binary(
+    name = "sha256sum2url_sh",
+    srcs = ["sha256sum2url.sh"],
+    visibility = ["//visibility:public"],
+)

bazel/defs.bzl

@@ -61,23 +61,25 @@ def _sha256sum2url_impl(ctx):
     """
     Returns cas url pointing to the artifact with checksum specified.
 
-    The rule does not check existance of the artifact!
-    Ensure that the corresponding rule that creates the artifact is remote cacheable!
+    Waits for the artifact to be published before returning url.
     """
     out = ctx.actions.declare_file(ctx.label.name)
     ctx.actions.run(
-        executable = "awk",
-        arguments = ["-v", "out=" + out.path, "-v", "base_url=" + ctx.attr.base_url, '{ printf "%s/cas/%s", base_url, $1 > out }', ctx.file.src.path],
+        executable = ctx.executable._sha256sum2url_sh,
         inputs = [ctx.file.src],
         outputs = [out],
+        env = {
+            "SHASUMFILE": ctx.file.src.path,
+            "OUT": out.path,
+        },
     )
     return [DefaultInfo(files = depset([out]), runfiles = ctx.runfiles(files = [out]))]
 
 sha256sum2url = rule(
     implementation = _sha256sum2url_impl,
     attrs = {
         "src": attr.label(allow_single_file = True),
-        "base_url": attr.string(default = "http://artifacts.idx.proxy-global.dfinity.network:8080"),
+        "_sha256sum2url_sh": attr.label(executable = True, cfg = "exec", default = "//bazel:sha256sum2url_sh"),
     },
 )
 

bazel/sha256sum2url.sh

@@ -0,0 +1,18 @@
+#!/usr/bin/env bash
+
+set -eEuo pipefail
+
+# TODO(IDX-2857): add timeout.
+
+BASE_URL_DIRECT='https://artifacts.idx.dfinity.network'
+BASE_URL_PROXY='http://artifacts.idx.proxy-global.dfinity.network:8080'
+
+SHASUM="$(cat "${SHASUMFILE}")"
+
+DIRECT_URL="${BASE_URL_DIRECT}/cas/${SHASUM}"
+
+while ! curl --head --fail "${DIRECT_URL}"; do
+    sleep 5
+done
+
+echo -n "${BASE_URL_PROXY}/cas/${SHASUM}" >"${OUT}"