From 8f76ab4f5335c23f57be87811a9e4c72f5dd92ad Mon Sep 17 00:00:00 2001
From: Angus Lees <gus@inodes.org>
Date: Thu, 22 Jun 2017 09:27:50 +1000
Subject: [PATCH] Add native convenience functions to parse JSON and YAML
Fixes #12
---
Makefile | 7 ++++-
README.md | 1 +
cmd/root.go | 2 ++
lib/kubecfg.libsonnet | 11 ++++++++
lib/kubecfg_test.jsonnet | 20 +++++++++++++
utils/nativefuncs.go | 33 ++++++++++++++++++++++
utils/nativefuncs_test.go | 59 +++++++++++++++++++++++++++++++++++++++
7 files changed, 132 insertions(+), 1 deletion(-)
create mode 100644 lib/kubecfg.libsonnet
create mode 100644 lib/kubecfg_test.jsonnet
create mode 100644 utils/nativefuncs.go
create mode 100644 utils/nativefuncs_test.go
diff --git a/Makefile b/Makefile
index 4f36f1fd..48969bc1 100644
--- a/Makefile
+++ b/Makefile
@@ -12,9 +12,14 @@ all: kubecfg
kubecfg:
$(GO) build $(GO_FLAGS) .
-test:
+test: gotest jsonnettest
+
+gotest:
$(GO) test $(GO_FLAGS) $(GO_PACKAGES)
+jsonnettest: kubecfg lib/kubecfg_test.jsonnet
+ ./kubecfg -J lib show lib/kubecfg_test.jsonnet
+
vet:
$(GO) vet $(GO_FLAGS) $(GO_PACKAGES)
diff --git a/README.md b/README.md
index 7adc1f01..969bebf8 100644
--- a/README.md
+++ b/README.md
@@ -63,6 +63,7 @@ avoid an immediate `Killed: 9`.
- Supports JSON, YAML or jsonnet files (by file suffix).
- Best-effort sorts objects before updating, so that dependencies are
pushed to the server before objects that refer to them.
+- Additional jsonnet builtin functions. See `lib/kubecfg.libsonnet`.
## Infrastructure-as-code Philosophy
diff --git a/cmd/root.go b/cmd/root.go
index 1bf86f61..9be10471 100644
--- a/cmd/root.go
+++ b/cmd/root.go
@@ -91,6 +91,8 @@ func JsonnetVM(cmd *cobra.Command) (*jsonnet.VM, error) {
vm.ExtVar(kv[0], kv[1])
}
+ utils.RegisterNativeFuncs(vm)
+
return vm, nil
}
diff --git a/lib/kubecfg.libsonnet b/lib/kubecfg.libsonnet
new file mode 100644
index 00000000..a6e271b4
--- /dev/null
+++ b/lib/kubecfg.libsonnet
@@ -0,0 +1,11 @@
+{
+ // parseJson(data): parses the `data` string as a json document, and
+ // returns the resulting jsonnet object.
+ parseJson:: std.native("parseJson"),
+
+ // parseYaml(data): parse the `data` string as a YAML stream, and
+ // returns an *array* of the resulting jsonnet objects. A single
+ // YAML document will still be returned as an array with one
+ // element.
+ parseYaml:: std.native("parseYaml"),
+}
diff --git a/lib/kubecfg_test.jsonnet b/lib/kubecfg_test.jsonnet
new file mode 100644
index 00000000..8184ee4b
--- /dev/null
+++ b/lib/kubecfg_test.jsonnet
@@ -0,0 +1,20 @@
+// Run me with `../kubecfg show kubecfg_test.jsonnet`
+local kubecfg = import "kubecfg.libsonnet";
+
+assert kubecfg.parseJson("[3, 4]") == [3, 4];
+
+local x = kubecfg.parseYaml("---
+- 3
+- 4
+---
+foo: bar
+baz: xyzzy
+");
+assert x == [[3, 4], {foo: "bar", baz: "xyzzy"}] : "got " + x;
+
+// Kubecfg wants to see something that looks like a k8s object
+{
+ apiVersion: "test",
+ kind: "Result",
+ result: "SUCCESS"
+}
diff --git a/utils/nativefuncs.go b/utils/nativefuncs.go
new file mode 100644
index 00000000..a6b4731e
--- /dev/null
+++ b/utils/nativefuncs.go
@@ -0,0 +1,33 @@
+package utils
+
+import (
+ "bytes"
+ "encoding/json"
+ "io"
+
+ jsonnet "github.com/strickyak/jsonnet_cgo"
+ "k8s.io/client-go/pkg/util/yaml"
+)
+
+func RegisterNativeFuncs(vm *jsonnet.VM) {
+ vm.NativeCallback("parseJson", []string{"json"}, func(data []byte) (res interface{}, err error) {
+ err = json.Unmarshal(data, &res)
+ return
+ })
+
+ vm.NativeCallback("parseYaml", []string{"yaml"}, func(data []byte) ([]interface{}, error) {
+ ret := []interface{}{}
+ d := yaml.NewYAMLToJSONDecoder(bytes.NewReader(data))
+ for {
+ var doc interface{}
+ if err := d.Decode(&doc); err != nil {
+ if err == io.EOF {
+ break
+ }
+ return nil, err
+ }
+ ret = append(ret, doc)
+ }
+ return ret, nil
+ })
+}
diff --git a/utils/nativefuncs_test.go b/utils/nativefuncs_test.go
new file mode 100644
index 00000000..6bcbc771
--- /dev/null
+++ b/utils/nativefuncs_test.go
@@ -0,0 +1,59 @@
+package utils
+
+import (
+ "testing"
+
+ jsonnet "github.com/strickyak/jsonnet_cgo"
+)
+
+// check there is no err, and a == b.
+func check(t *testing.T, err error, actual, expected string) {
+ if err != nil {
+ t.Errorf("Expected %q, got error: %q", expected, err.Error())
+ } else if actual != expected {
+ t.Errorf("Expected %q, got %q", expected, actual)
+ }
+}
+
+func TestParseJson(t *testing.T) {
+ vm := jsonnet.Make()
+ defer vm.Destroy()
+ RegisterNativeFuncs(vm)
+
+ _, err := vm.EvaluateSnippet("failtest", `std.native("parseJson")("barf{")`)
+ if err == nil {
+ t.Errorf("parseJson succeeded on invalid json")
+ }
+
+ x, err := vm.EvaluateSnippet("test", `std.native("parseJson")("null")`)
+ check(t, err, x, "null\n")
+
+ x, err = vm.EvaluateSnippet("test", `
+ local a = std.native("parseJson")('{"foo": 3, "bar": 4}');
+ a.foo + a.bar`)
+ check(t, err, x, "7\n")
+}
+
+func TestParseYaml(t *testing.T) {
+ vm := jsonnet.Make()
+ defer vm.Destroy()
+ RegisterNativeFuncs(vm)
+
+ _, err := vm.EvaluateSnippet("failtest", `std.native("parseYaml")("[barf")`)
+ if err == nil {
+ t.Errorf("parseYaml succeeded on invalid yaml")
+ }
+
+ x, err := vm.EvaluateSnippet("test", `std.native("parseYaml")("")`)
+ check(t, err, x, "[ ]\n")
+
+ x, err = vm.EvaluateSnippet("test", `
+ local a = std.native("parseYaml")("foo:\n- 3\n- 4\n")[0];
+ a.foo[0] + a.foo[1]`)
+ check(t, err, x, "7\n")
+
+ x, err = vm.EvaluateSnippet("test", `
+ local a = std.native("parseYaml")("---\nhello\n---\nworld");
+ a[0] + a[1]`)
+ check(t, err, x, "\"helloworld\"\n")
+}
--
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