tools/bzl/js.bzl

load("@npm//@bazel/rollup:index.bzl", "rollup_bundle")
load("@npm//@bazel/terser:index.bzl", "terser_minified")
load("//tools/bzl:genrule2.bzl", "genrule2")

ComponentInfo = provider()

def _js_component(ctx):
    dir = ctx.outputs.zip.path + ".dir"
    name = ctx.outputs.zip.basename
    if name.endswith(".zip"):
        name = name[:-4]
    dest = "%s/%s" % (dir, name)
    cmd = " && ".join([
        "TZ=UTC",
        "export TZ",
        "mkdir -p %s" % dest,
        "cp %s %s/" % (" ".join([s.path for s in ctx.files.srcs]), dest),
        "cd %s" % dir,
        "find . -exec touch -t 198001010000 '{}' ';'",
        "zip -Xqr ../%s *" % ctx.outputs.zip.basename,
    ])

    ctx.actions.run_shell(
        inputs = ctx.files.srcs,
        outputs = [ctx.outputs.zip],
        command = cmd,
        mnemonic = "GenJsComponentZip",
    )

    licenses = []
    if ctx.file.license:
        licenses.append(ctx.file.license)

    return [
        ComponentInfo(
            transitive_licenses = depset(licenses),
            transitive_versions = depset(),
            transitive_zipfiles = list([ctx.outputs.zip]),
        ),
    ]

js_component = rule(
    _js_component,
    attrs = {
        "srcs": attr.label_list(allow_files = [".js"]),
        "license": attr.label(allow_single_file = True),
    },
    outputs = {
        "zip": "%{name}.zip",
    },
)

def polygerrit_plugin(name, app, plugin_name = None):
    """Produces plugin file set with minified javascript.

    This rule minifies a plugin javascript file, potentially renames it, and produces a file set.
    Output of this rule is a FileSet with "${plugin_name}.js".

    Args:
      name: String, rule name.
      app: String, the main or root source file. This must be single JavaScript file.
      plugin_name: String, plugin name. ${name} is used if not provided.
    """
    if not plugin_name:
        plugin_name = name

    terser_minified(
        name = plugin_name + ".min",
        sourcemap = False,
        src = app,
    )

    native.genrule(
        name = name + "_rename_js",
        srcs = [plugin_name + ".min"],
        outs = [plugin_name + ".js"],
        cmd = "cp $< $@",
        output_to_bindir = True,
    )

    native.filegroup(
        name = name,
        srcs = [plugin_name + ".js"],
    )

def gerrit_js_bundle(name, entry_point, srcs = []):
    """Produces a Gerrit JavaScript bundle archive.

    This rule bundles and minifies the javascript files of a frontend plugin and
    produces a file archive.
    Output of this rule is an archive with "${name}.jar" with specific layout for
    Gerrit frontend plugins. That archive should be provided to gerrit_plugin
    rule as resource_jars attribute.

    Args:
      name: Rule name.
      srcs: Plugin sources.
      entry_point: Plugin entry_point.
    """

    bundle = name + "-bundle"
    minified = name + ".min"
    main = name + ".js"

    rollup_bundle(
        name = bundle,
        srcs = srcs,
        entry_point = entry_point,
        format = "iife",
        rollup_bin = "//tools/node_tools:rollup-bin",
        sourcemap = "hidden",
        deps = [
            "@tools_npm//rollup-plugin-node-resolve",
        ],
    )

    terser_minified(
        name = minified,
        sourcemap = False,
        src = bundle,
    )

    native.genrule(
        name = name + "_rename_js",
        srcs = [minified],
        outs = [main],
        cmd = "cp $< $@",
        output_to_bindir = True,
    )

    genrule2(
        name = name,
        srcs = [main],
        outs = [name + ".jar"],
        cmd = " && ".join([
            "mkdir $$TMP/static",
            "cp $(SRCS) $$TMP/static",
            "cd $$TMP",
            "zip -Drq $$ROOT/$@ -g .",
        ]),
    )