Initial commit

.gitignore

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+bazel-*
+.tags
+.tags.lock
+.tags.temp

WORKSPACE

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+workspace(name = "com_github_yujunz_rules_helm")
+
+load("@com_github_yujunz_rules_helm//helm:deps.bzl", "helm_register_toolchains", "helm_rules_dependencies")
+helm_rules_dependencies()
+helm_register_toolchains()

helm/BUILD.bazel

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+toolchain_type(
+    name = "toolchain",
+    visibility = ["//visibility:public"],
+)

helm/def.bzl

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+def _helm_chart_impl(ctx):
+    return []
+
+def helm_chart():
+    return rule(
+        implementation = _helm_chart_impl,
+        attrs = {},
+        toolchains = ["@com_github_yujunz_rules_helm//helm:toolchain"],
+        **kwargs
+    )

helm/deps.bzl

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+def helm_rules_dependencies():
+    pass
+
+def helm_register_toolchains():
+    pass

helm/platforms.bzl

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+BAZEL_HELM_OS_CONSTRAINTS = {
+    "darwin": "@bazel_tools//platforms:osx",
+    "linux": "@bazel_tools//platforms:linux",
+}
+
+BAZEL_HELM_ARCH_CONSTRAINTS = {
+    "amd64": "@bazel_tools//platforms:x86_64",
+}
+
+HELM_OS_ARCH = (
+    ("darwin", "amd64"),
+    ("linux", "amd64"),
+)
+
+def _generate_constraints(names, bazel_constraints):
+    return {
+        name: bazel_constraints.get(name, "@com_github_yujunz_rules_helm//helm/toolchain:" + name)
+        for name in names
+    }
+
+HELM_OS_CONSTRAINTS = _generate_constraints([p[0] for p in HELM_OS_ARCH], BAZEL_HELM_OS_CONSTRAINTS)
+HELM_ARCH_CONSTRAINTS = _generate_constraints([p[1] for p in HELM_OS_ARCH], BAZEL_HELM_ARCH_CONSTRAINTS)
+
+def _generate_platforms():
+    platforms = []
+    for os, arch in HELM_OS_ARCH:
+        constraints = [
+            HELM_OS_CONSTRAINTS[os],
+            HELM_ARCH_CONSTRAINTS[arch],
+        ]
+        platforms.append(struct(
+            name = os + "_" + arch,
+            os = os,
+            arch = arch,
+            constraints = constraints,
+        ))
+    return platforms
+
+PLATFORMS = _generate_platforms()
+
+def generate_toolchain_names():
+    # keep in sync with declare_toolchains
+    return ["helm_" + p.name for p in PLATFORMS]

helm/toolchain/BUILD.bazel

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+load(
+    ":toolchains.bzl",
+    "declare_constraints",
+)
+
+package(default_visibility = ["//visibility:public"])
+
+declare_constraints()
+
+filegroup(
+    name = "all_files",
+    testonly = True,
+    srcs = glob(["**"]),
+    visibility = ["//visibility:public"],
+)

helm/toolchain/toolchains.bzl

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+load(
+    "@com_github_yujunz_rules_helm//helm:platforms.bzl",
+    "HELM_ARCH_CONSTRAINTS",
+    "HELM_OS_CONSTRAINTS",
+    "PLATFORMS",
+)
+
+def declare_constraints():
+    """Generates constraint_values and platform targets for valid platforms.
+
+    Each constraint_value corresponds to a valid os or goarch.
+    The os and goarch values belong to the constraint_settings
+    @bazel_tools//platforms:os and @bazel_tools//platforms:cpu, respectively.
+    To avoid redundancy, if there is an equivalent value in @bazel_tools,
+    we define an alias here instead of another constraint_value.
+
+    Each platform defined here selects a os and goarch constraint value.
+    These platforms may be used with --platforms for cross-compilation,
+    though users may create their own platforms (and
+    @bazel_tools//platforms:default_platform will be used most of the time).
+    """
+    for os, constraint in HELM_OS_CONSTRAINTS.items():
+        if constraint.startswith("@com_github_yujunz_rules_helm//helm/toolchain:"):
+            native.constraint_value(
+                name = os,
+                constraint_setting = "@bazel_tools//platforms:os",
+            )
+        else:
+            native.alias(
+                name = os,
+                actual = constraint,
+            )
+
+    for arch, constraint in HELM_ARCH_CONSTRAINTS.items():
+        if constraint.startswith("@com_github_yujunz_rules_helm//helm/toolchain:"):
+            native.constraint_value(
+                name = arch,
+                constraint_setting = "@bazel_tools//platforms:cpu",
+            )
+        else:
+            native.alias(
+                name = arch,
+                actual = constraint,
+            )
+
+    for p in PLATFORMS:
+        native.platform(
+            name = p.name,
+            constraint_values = p.constraints,
+        )