build: do not bundle management API docs by default

This reduces the build time and binary size

GitOrigin-RevId: 527ff9f044ac347cbf96195f5e3560fd1680fde5

BUILD.bazel

@@ -1,3 +1,4 @@
+load("@bazel_skylib//rules:common_settings.bzl", "bool_flag")
 load("@bazel_gazelle//:def.bzl", "gazelle")
 load("@rules_pkg//:pkg.bzl", "pkg_tar")
 load("@io_bazel_rules_go//go:def.bzl", "nogo")
@@ -36,6 +37,19 @@ flake8_lint_config(
     ],
 )
 
+# Add a build flag to enable bundling the management API documentation with the
+# binaries. This can be enabled by passing --//:mgmtapi_bundle_doc=true when
+# invoking bazel
+bool_flag(
+    name = "mgmtapi_bundle_doc",
+    build_setting_default = False,
+)
+
+config_setting(
+    name = "mgmtapi_bundle_doc_build",
+    flag_values = {":mgmtapi_bundle_doc": "true"},
+)
+
 # This is the SCION distributable package. It contains all (binary) services,
 # and the required tools.
 pkg_tar(

control/mgmtapi/BUILD.bazel

@@ -29,7 +29,10 @@ go_library(
         "spec.go",
         ":api_generated",  # keep
     ],
-    embedsrcs = [":bundle"],  # keep
+    embedsrcs = select({
+        "//:mgmtapi_bundle_doc_build": [":bundle"],
+        "//conditions:default": [":dummy.html"],
+    }),  # keep
     importpath = "github.com/scionproto/scion/control/mgmtapi",
     visibility = ["//visibility:public"],
     deps = [

control/mgmtapi/spec.go

@@ -16,15 +16,19 @@ package mgmtapi
 
 import (
 	"bytes"
-	_ "embed"
+	"embed"
 	"net/http"
 	"time"
+
+	"github.com/scionproto/scion/private/mgmtapi"
 )
 
-//go:embed index.html
-var index []byte
+//go:embed *.html
+var f embed.FS
 
 var (
+	index = mgmtapi.ResolveIndex(f)
+
 	modtime = time.Now()
 
 	spec = func() []byte {

daemon/mgmtapi/BUILD.bazel

@@ -29,10 +29,14 @@ go_library(
         "spec.go",
         ":api_generated",  # keep
     ],
-    embedsrcs = [":bundle"],  # keep
+    embedsrcs = select({
+        "//:mgmtapi_bundle_doc_build": [":bundle"],
+        "//conditions:default": [":dummy.html"],
+    }),  # keep
     importpath = "github.com/scionproto/scion/daemon/mgmtapi",
     visibility = ["//visibility:public"],
     deps = [
+        "//private/mgmtapi:go_default_library",
         "//private/mgmtapi/cppki/api:go_default_library",
         "//private/mgmtapi/segments/api:go_default_library",
         "@com_github_deepmap_oapi_codegen//pkg/runtime:go_default_library",  # keep

daemon/mgmtapi/spec.go

@@ -16,15 +16,19 @@ package mgmtapi
 
 import (
 	"bytes"
-	_ "embed"
+	"embed"
 	"net/http"
 	"time"
+
+	"github.com/scionproto/scion/private/mgmtapi"
 )
 
-//go:embed index.html
-var index []byte
+//go:embed *.html
+var f embed.FS
 
 var (
+	index = mgmtapi.ResolveIndex(f)
+
 	modtime = time.Now()
 
 	spec = func() []byte {

dispatcher/mgmtapi/BUILD.bazel

@@ -29,10 +29,14 @@ go_library(
         "spec.go",
         ":api_generated",  # keep
     ],
-    embedsrcs = [":bundle"],  # keep
+    embedsrcs = select({
+        "//:mgmtapi_bundle_doc_build": [":bundle"],
+        "//conditions:default": [":dummy.html"],
+    }),  # keep
     importpath = "github.com/scionproto/scion/dispatcher/mgmtapi",
     visibility = ["//visibility:public"],
     deps = [
+        "//private/mgmtapi:go_default_library",
         "@com_github_getkin_kin_openapi//openapi3:go_default_library",  # keep
         "@com_github_go_chi_chi_v5//:go_default_library",  # keep
     ],

dispatcher/mgmtapi/spec.go

@@ -16,15 +16,19 @@ package mgmtapi
 
 import (
 	"bytes"
-	_ "embed"
+	"embed"
 	"net/http"
 	"time"
+
+	"github.com/scionproto/scion/private/mgmtapi"
 )
 
-//go:embed index.html
-var index []byte
+//go:embed *.html
+var f embed.FS
 
 var (
+	index = mgmtapi.ResolveIndex(f)
+
 	modtime = time.Now()
 
 	spec = func() []byte {

gateway/mgmtapi/BUILD.bazel

@@ -29,10 +29,14 @@ go_library(
         "spec.go",
         ":api_generated",  # keep
     ],
-    embedsrcs = [":bundle"],  # keep
+    embedsrcs = select({
+        "//:mgmtapi_bundle_doc_build": [":bundle"],
+        "//conditions:default": [":dummy.html"],
+    }),  # keep
     importpath = "github.com/scionproto/scion/gateway/mgmtapi",
     visibility = ["//visibility:public"],
     deps = [
+        "//private/mgmtapi:go_default_library",
         "@com_github_deepmap_oapi_codegen//pkg/runtime:go_default_library",  # keep
         "@com_github_getkin_kin_openapi//openapi3:go_default_library",  # keep
         "@com_github_go_chi_chi_v5//:go_default_library",  # keep

gateway/mgmtapi/spec.go

@@ -16,15 +16,19 @@ package mgmtapi
 
 import (
 	"bytes"
-	_ "embed"
+	"embed"
 	"net/http"
 	"time"
+
+	"github.com/scionproto/scion/private/mgmtapi"
 )
 
-//go:embed index.html
-var index []byte
+//go:embed *.html
+var f embed.FS
 
 var (
+	index = mgmtapi.ResolveIndex(f)
+
 	modtime = time.Now()
 
 	spec = func() []byte {

private/mgmtapi/BUILD.bazel

@@ -6,7 +6,9 @@ go_library(
         "config.go",
         "errors.go",
         "helpers.go",
+        "spec.go",
     ],
+    embedsrcs = ["index.html"],
     importpath = "github.com/scionproto/scion/private/mgmtapi",
     visibility = ["//visibility:public"],
     deps = ["//private/config:go_default_library"],

private/mgmtapi/index.html

@@ -0,0 +1,13 @@
+<!DOCTYPE html>
+<html>
+
+<body>
+    <h1>Service Management UI not bundled</h1>
+
+    The service management UI is not bundled in this binary.
+
+    The OpenAPI spec is available at <a href="./spec.json">/spec.json</a>
+
+</body>
+
+</html>

private/mgmtapi/spec.go

@@ -0,0 +1,37 @@
+// Copyright 2022 Anapaya Systems
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package mgmtapi
+
+import (
+	"embed"
+	"errors"
+	"io/fs"
+)
+
+//go:embed index.html
+var index []byte
+
+// ResolveIndex resolves the service management API index page from the passed
+// filesystem. If it is not present, a placeholder is returned.
+func ResolveIndex(f embed.FS) []byte {
+	raw, err := f.ReadFile("index.html")
+	if errors.Is(err, fs.ErrNotExist) {
+		return append([]byte(nil), index...)
+	}
+	if err != nil {
+		panic(err)
+	}
+	return raw
+}

router/mgmtapi/BUILD.bazel

@@ -29,7 +29,10 @@ go_library(
         "spec.go",
         ":api_generated",  # keep
     ],
-    embedsrcs = [":bundle"],  # keep
+    embedsrcs = select({
+        "//:mgmtapi_bundle_doc_build": [":bundle"],
+        "//conditions:default": [":dummy.html"],
+    }),  # keep
     importpath = "github.com/scionproto/scion/router/mgmtapi",
     visibility = ["//visibility:public"],
     deps = [

router/mgmtapi/spec.go

@@ -16,15 +16,19 @@ package mgmtapi
 
 import (
 	"bytes"
-	_ "embed"
+	"embed"
 	"net/http"
 	"time"
+
+	"github.com/scionproto/scion/private/mgmtapi"
 )
 
-//go:embed index.html
-var index []byte
+//go:embed *.html
+var f embed.FS
 
 var (
+	index = mgmtapi.ResolveIndex(f)
+
 	modtime = time.Now()
 
 	spec = func() []byte {