bake: x-bake extension field with compose

bake/compose.go

@@ -80,13 +80,15 @@ func ParseCompose(dt []byte) (*Config, error) {
 					return val, ok
 				})),
 				CacheFrom: s.Build.CacheFrom,
-				// TODO: add platforms
+			}
+			if err = t.composeExtTarget(s.Build.Extensions); err != nil {
+				return nil, err
 			}
 			if s.Build.Target != "" {
 				target := s.Build.Target
 				t.Target = &target
 			}
-			if s.Image != "" {
+			if len(t.Tags) == 0 && s.Image != "" {
 				t.Tags = []string{s.Image}
 			}
 			c.Targets = append(c.Targets, t)
@@ -111,3 +113,82 @@ func flatten(in compose.MappingWithEquals) compose.Mapping {
 	}
 	return out
 }
+
+// composeExtTarget converts Compose build extension x-bake to bake Target
+// https://github.com/compose-spec/compose-spec/blob/master/spec.md#extension
+func (t *Target) composeExtTarget(exts map[string]interface{}) error {
+	if ext, ok := exts["x-bake"]; ok {
+		for key, val := range ext.(map[string]interface{}) {
+			switch key {
+			case "tags":
+				if res, k := val.(string); k {
+					t.Tags = append(t.Tags, res)
+				} else {
+					for _, res := range val.([]interface{}) {
+						t.Tags = append(t.Tags, res.(string))
+					}
+				}
+			case "cache-from":
+				t.CacheFrom = []string{} // Needed to override the main field
+				if res, k := val.(string); k {
+					t.CacheFrom = append(t.CacheFrom, res)
+				} else {
+					for _, res := range val.([]interface{}) {
+						t.CacheFrom = append(t.CacheFrom, res.(string))
+					}
+				}
+			case "cache-to":
+				if res, k := val.(string); k {
+					t.CacheTo = append(t.CacheTo, res)
+				} else {
+					for _, res := range val.([]interface{}) {
+						t.CacheTo = append(t.CacheTo, res.(string))
+					}
+				}
+			case "secret":
+				if res, k := val.(string); k {
+					t.Secrets = append(t.Secrets, res)
+				} else {
+					for _, res := range val.([]interface{}) {
+						t.Secrets = append(t.Secrets, res.(string))
+					}
+				}
+			case "ssh":
+				if res, k := val.(string); k {
+					t.SSH = append(t.SSH, res)
+				} else {
+					for _, res := range val.([]interface{}) {
+						t.SSH = append(t.SSH, res.(string))
+					}
+				}
+			case "platforms":
+				if res, k := val.(string); k {
+					t.Platforms = append(t.Platforms, res)
+				} else {
+					for _, res := range val.([]interface{}) {
+						t.Platforms = append(t.Platforms, res.(string))
+					}
+				}
+			case "output":
+				if res, k := val.(string); k {
+					t.Outputs = append(t.Outputs, res)
+				} else {
+					for _, res := range val.([]interface{}) {
+						t.Outputs = append(t.Outputs, res.(string))
+					}
+				}
+			case "pull":
+				if res, ok := val.(bool); ok {
+					t.Pull = &res
+				}
+			case "no-cache":
+				if res, ok := val.(bool); ok {
+					t.NoCache = &res
+				}
+			default:
+				return fmt.Errorf("compose file invalid: unkwown %s field for x-bake", key)
+			}
+		}
+	}
+	return nil
+}

bake/compose_test.go

@@ -214,3 +214,70 @@ networks:
 	_, err := ParseCompose(dt)
 	require.NoError(t, err)
 }
+
+func TestComposeExt(t *testing.T) {
+	var dt = []byte(`
+services:
+  addon:
+    image: ct-addon:bar
+    build:
+      context: .
+      dockerfile: ./Dockerfile
+      cache_from:
+        - user/app:cache
+      args:
+        CT_ECR: foo
+        CT_TAG: bar
+      x-bake:
+        tags:
+          - ct-addon:foo
+          - ct-addon:alp
+        platforms:
+          - linux/amd64
+          - linux/arm64
+        cache-from:
+          - type=local,src=path/to/cache
+        cache-to: local,dest=path/to/cache
+        pull: true
+
+  aws:
+    image: ct-fake-aws:bar
+    build:
+      dockerfile: ./aws.Dockerfile
+      args:
+        CT_ECR: foo
+        CT_TAG: bar
+      x-bake:
+        secret:
+          - id=mysecret,src=/local/secret
+          - id=mysecret2,src=/local/secret2
+        ssh: default
+        platforms: linux/arm64
+        output: type=docker
+        no-cache: true
+`)
+
+	c, err := ParseCompose(dt)
+	require.NoError(t, err)
+	require.Equal(t, 2, len(c.Targets))
+	sort.Slice(c.Targets, func(i, j int) bool {
+		return c.Targets[i].Name < c.Targets[j].Name
+	})
+	require.Equal(t, c.Targets[0].Args, map[string]string{"CT_ECR": "foo", "CT_TAG": "bar"})
+	require.Equal(t, c.Targets[0].Tags, []string{"ct-addon:foo", "ct-addon:alp"})
+	require.Equal(t, c.Targets[0].Platforms, []string{"linux/amd64", "linux/arm64"})
+	require.Equal(t, c.Targets[0].CacheFrom, []string{"type=local,src=path/to/cache"})
+	require.Equal(t, c.Targets[0].CacheTo, []string{"local,dest=path/to/cache"})
+	require.Equal(t, c.Targets[0].Pull, newBool(true))
+	require.Equal(t, c.Targets[1].Tags, []string{"ct-fake-aws:bar"})
+	require.Equal(t, c.Targets[1].Secrets, []string{"id=mysecret,src=/local/secret", "id=mysecret2,src=/local/secret2"})
+	require.Equal(t, c.Targets[1].SSH, []string{"default"})
+	require.Equal(t, c.Targets[1].Platforms, []string{"linux/arm64"})
+	require.Equal(t, c.Targets[1].Outputs, []string{"type=docker"})
+	require.Equal(t, c.Targets[1].NoCache, newBool(true))
+}
+
+func newBool(val bool) *bool {
+	b := val
+	return &b
+}

docs/reference/buildx_bake.md

@@ -686,3 +686,108 @@ $ docker buildx bake --print app
   }
 }
 ```
+
+### Extension field with Compose
+
+[Special extension](https://github.com/compose-spec/compose-spec/blob/master/spec.md#extension)
+field `x-bake` can be used in your compose file to evaluate fields that are not
+(yet) available in the [build definition](https://github.com/compose-spec/compose-spec/blob/master/build.md#build-definition).
+
+```yaml
+# docker-compose.yml
+services:
+  addon:
+    image: ct-addon:bar
+    build:
+      context: .
+      dockerfile: ./Dockerfile
+      args:
+        CT_ECR: foo
+        CT_TAG: bar
+      x-bake:
+        tags:
+          - ct-addon:foo
+          - ct-addon:alp
+        platforms:
+          - linux/amd64
+          - linux/arm64
+        cache-from:
+          - user/app:cache
+          - type=local,src=path/to/cache
+        cache-to: type=local,dest=path/to/cache
+        pull: true
+
+  aws:
+    image: ct-fake-aws:bar
+    build:
+      dockerfile: ./aws.Dockerfile
+      args:
+        CT_ECR: foo
+        CT_TAG: bar
+      x-bake:
+        secret:
+          - id=mysecret,src=./secret
+          - id=mysecret2,src=./secret2
+        platforms: linux/arm64
+        output: type=docker
+        no-cache: true
+```
+
+```console
+$ docker buildx bake --print
+{
+  "target": {
+    "addon": {
+      "context": ".",
+      "dockerfile": "./Dockerfile",
+      "args": {
+        "CT_ECR": "foo",
+        "CT_TAG": "bar"
+      },
+      "tags": [
+        "ct-addon:foo",
+        "ct-addon:alp"
+      ],
+      "cache-from": [
+        "user/app:cache",
+        "type=local,src=path/to/cache"
+      ],
+      "cache-to": [
+        "type=local,dest=path/to/cache"
+      ],
+      "platforms": [
+        "linux/amd64",
+        "linux/arm64"
+      ],
+      "pull": true
+    },
+    "aws": {
+      "context": ".",
+      "dockerfile": "./aws.Dockerfile",
+      "args": {
+        "CT_ECR": "foo",
+        "CT_TAG": "bar"
+      },
+      "tags": [
+        "ct-fake-aws:bar"
+      ],
+      "secret": [
+        "id=mysecret,src=./secret",
+        "id=mysecret2,src=./secret2"
+      ],
+      "platforms": [
+        "linux/arm64"
+      ],
+      "output": [
+        "type=docker"
+      ],
+      "no-cache": true
+    }
+  }
+}
+```
+
+Complete list of valid fields for `x-bake`:
+
+`tags`, `cache-from`, `cache-to`, `secret`, `ssh`, `platforms`, `output`,
+`pull`, `no-cache`