Merge pull request #280 from vanstee/hcl-json-support

Support parsing json config with hcl v2

bake/bake.go

@@ -72,8 +72,8 @@ func ParseFile(fn string) (*Config, error) {
 
 type Config struct {
 	Variables []*Variable `json:"-" hcl:"variable,block"`
-	Groups    []*Group    `json:"groups" hcl:"group,block"`
+	Groups    []*Group    `json:"group" hcl:"group,block"`
-	Targets   []*Target   `json:"targets" hcl:"target,block"`
+	Targets   []*Target   `json:"target" hcl:"target,block"`
 	Remain    hcl.Body    `json:"-" hcl:",remain"`
 }
 

bake/hcl.go

@@ -8,6 +8,7 @@ import (
 	"github.com/hashicorp/hcl/v2/ext/userfunc"
 	"github.com/hashicorp/hcl/v2/hclsimple"
 	"github.com/hashicorp/hcl/v2/hclsyntax"
+	"github.com/hashicorp/hcl/v2/json"
 	"github.com/zclconf/go-cty/cty"
 	"github.com/zclconf/go-cty/cty/function"
 	"github.com/zclconf/go-cty/cty/function/stdlib"
@@ -103,10 +104,20 @@ type staticConfig struct {
 }
 
 func ParseHCL(dt []byte, fn string) (*Config, error) {
-	// Decode user defined functions.
+	// Decode user defined functions, first parsing as hcl and falling back to
-	file, diags := hclsyntax.ParseConfig(dt, fn, hcl.Pos{Line: 1, Column: 1})
+	// json, returning errors based on the file suffix.
-	if diags.HasErrors() {
+	file, hcldiags := hclsyntax.ParseConfig(dt, fn, hcl.Pos{Line: 1, Column: 1})
-		return nil, diags
+	if hcldiags.HasErrors() {
+		var jsondiags hcl.Diagnostics
+		file, jsondiags = json.Parse(dt, fn)
+		if jsondiags.HasErrors() {
+			fnl := strings.ToLower(fn)
+			if strings.HasSuffix(fnl, ".json") {
+				return nil, jsondiags
+			} else {
+				return nil, hcldiags
+			}
+		}
 	}
 
 	userFunctions, _, diags := userfunc.DecodeUserFunctions(file.Body, "function", func() *hcl.EvalContext {

bake/hcl_test.go

@@ -68,6 +68,66 @@ func TestParseHCL(t *testing.T) {
 		require.Equal(t, map[string]string{"IAMCROSS": "true"}, c.Targets[3].Args)
 	})
 
+	t.Run("BasicInJSON", func(t *testing.T) {
+		dt := []byte(`
+		{
+			"group": {
+				"default": {
+					"targets": ["db", "webapp"]
+				}
+			},
+			"target": {
+				"db": {
+					"context": "./db",
+					"tags": ["docker.io/tonistiigi/db"]
+				},
+				"webapp": {
+					"context": "./dir",
+					"dockerfile": "Dockerfile-alternate",
+					"args": {
+						"buildno": "123"
+					}
+				},
+				"cross": {
+					"platforms": [
+						"linux/amd64",
+						"linux/arm64"
+					]
+				},
+				"webapp-plus": {
+					"inherits": ["webapp", "cross"],
+					"args": {
+						"IAMCROSS": "true"
+					}
+				}
+			}
+		}
+		`)
+
+		c, err := ParseHCL(dt, "docker-bake.json")
+		require.NoError(t, err)
+
+		require.Equal(t, 1, len(c.Groups))
+		require.Equal(t, "default", c.Groups[0].Name)
+		require.Equal(t, []string{"db", "webapp"}, c.Groups[0].Targets)
+
+		require.Equal(t, 4, len(c.Targets))
+		require.Equal(t, c.Targets[0].Name, "db")
+		require.Equal(t, "./db", *c.Targets[0].Context)
+
+		require.Equal(t, c.Targets[1].Name, "webapp")
+		require.Equal(t, 1, len(c.Targets[1].Args))
+		require.Equal(t, "123", c.Targets[1].Args["buildno"])
+
+		require.Equal(t, c.Targets[2].Name, "cross")
+		require.Equal(t, 2, len(c.Targets[2].Platforms))
+		require.Equal(t, []string{"linux/amd64", "linux/arm64"}, c.Targets[2].Platforms)
+
+		require.Equal(t, c.Targets[3].Name, "webapp-plus")
+		require.Equal(t, 1, len(c.Targets[3].Args))
+		require.Equal(t, map[string]string{"IAMCROSS": "true"}, c.Targets[3].Args)
+	})
+
 	t.Run("WithFunctions", func(t *testing.T) {
 		dt := []byte(`
 		group "default" {