bazel: Add json_data and writers

api/bazel/BUILD

@@ -1,4 +1,6 @@
 load("@io_bazel_rules_go//proto:compiler.bzl", "go_proto_compiler")
+load("//:utils.bzl", "json_data")
+load(":repository_locations.bzl", "REPOSITORY_LOCATIONS_SPEC")
 
 licenses(["notice"])  # Apache 2
 
@@ -15,3 +17,8 @@ go_proto_compiler(
     valid_archive = False,
     visibility = ["//visibility:public"],
 )
+
+json_data(
+    name = "repository_locations",
+    data = REPOSITORY_LOCATIONS_SPEC,
+)

bazel/BUILD

@@ -1,8 +1,10 @@
 load("@rules_cc//cc:defs.bzl", "cc_library", "cc_proto_library")
 load("//bazel:envoy_build_system.bzl", "envoy_package")
 load("//bazel:envoy_internal.bzl", "envoy_select_force_libcpp")
+load("//bazel:utils.bzl", "json_data")
 load("@bazel_skylib//lib:selects.bzl", "selects")
 load("@bazel_skylib//rules:common_settings.bzl", "bool_flag")
+load(":repository_locations.bzl", "REPOSITORY_LOCATIONS_SPEC")
 
 licenses(["notice"])  # Apache 2
 
@@ -591,3 +593,8 @@ alias(
     name = "windows",
     actual = "@bazel_tools//src/conditions:windows",
 )
+
+json_data(
+    name = "repository_locations",
+    data = REPOSITORY_LOCATIONS_SPEC,
+)

bazel/api_binding.bzl

@@ -13,6 +13,7 @@ def _default_envoy_api_impl(ctx):
     ]
     for d in api_dirs:
         ctx.symlink(ctx.path(ctx.attr.envoy_root).dirname.get_child(ctx.attr.reldir).get_child(d), d)
+    ctx.symlink(ctx.path(ctx.attr.envoy_root).dirname.get_child("bazel").get_child("utils.bzl"), "utils.bzl")
 
 _default_envoy_api = repository_rule(
     implementation = _default_envoy_api_impl,

bazel/utils.bzl

@@ -0,0 +1,18 @@
+load("@bazel_skylib//rules:write_file.bzl", "write_file")
+
+def json_data(
+        name,
+        data,
+        visibility = ["//visibility:public"],
+        **kwargs):
+    """Write a bazel object to a file
+
+    The provided `data` object should be json serializable.
+    """
+    write_file(
+        name = name,
+        out = "%s.json" % name,
+        content = json.encode(data).split("\n"),
+        visibility = visibility,
+        **kwargs
+    )

contrib/BUILD

@@ -1,6 +1,14 @@
+load("//bazel:utils.bzl", "json_data")
+load(":contrib_build_config.bzl", "CONTRIB_EXTENSIONS")
+
 licenses(["notice"])  # Apache 2
 
 exports_files([
     "extensions_metadata.yaml",
     "contrib_build_config.bzl",
 ])
+
+json_data(
+    name = "contrib_extensions_build_config",
+    data = CONTRIB_EXTENSIONS,
+)

source/extensions/BUILD

@@ -1,6 +1,14 @@
+load("//bazel:utils.bzl", "json_data")
+load(":extensions_build_config.bzl", "EXTENSIONS")
+
 licenses(["notice"])  # Apache 2
 
 exports_files([
     "extensions_metadata.yaml",
     "extensions_build_config.bzl",
 ])
+
+json_data(
+    name = "extensions_build_config",
+    data = EXTENSIONS,
+)