Experimental way to expose tasks, adding them to global scope.

features/expose.feature

@@ -0,0 +1,70 @@
+Feature: Exposing imported package tasks so they can be invoked without the alias.
+
+Background:
+  Given I'm in project dir
+
+
+Scenario: Expose tasks
+  Given file ./Oyafile containing
+    """
+    Project: main
+    """
+  And file ./project1/Oyafile containing
+    """
+    Values:
+      foo: project1
+
+    echo: |
+      echo "project1"
+    """
+  And file ./project2/Oyafile containing
+    """
+    Import:
+      p: /project1
+
+    Expose: p
+    """
+  And I'm in the ./project2 dir
+  When I run "oya run echo"
+  Then the command succeeds
+  And the command outputs
+  """
+  project1
+
+  """
+
+@current
+Scenario: Never overwrite existing an task when exposing tasks
+  Given file ./Oyafile containing
+    """
+    Project: main
+    """
+  And file ./project1/Oyafile containing
+    """
+    Values:
+      foo: project1
+
+    echo: |
+      echo "project1"
+    """
+  And file ./project2/Oyafile containing
+    """
+    Import:
+      p: /project1
+
+    Expose: p
+
+    echo: |
+      echo "project2"
+    """
+  And I'm in the ./project2 dir
+  When I run "oya run echo"
+  Then the command succeeds
+  And the command outputs
+  """
+  project2
+
+  """
+
+
+# TODO: Show as aliases when listing tasks.

pkg/oyafile/imports.go

@@ -36,11 +36,13 @@ func (oyafile *Oyafile) resolveImports(loader PackLoader) error {
 		if err != nil {
 			return err
 		}
+
+		// TODO(bilus): Extract function.
 		err = oyafile.Values.UpdateScopeAt(string(alias),
 			func(scope template.Scope) template.Scope {
 				// Values in the main Oyafile overwrite values in the pack Oyafile.
 				merged := packOyafile.Values.Merge(scope)
-				// Task is keeping a pointed to the scope.
+				// Task is keeping a pointer to the scope.
 				packOyafile.Values.Replace(merged)
 				return merged
 			}, false)
@@ -51,6 +53,13 @@ func (oyafile *Oyafile) resolveImports(loader PackLoader) error {
 		oyafile.Tasks.ImportTasks(alias, packOyafile.Tasks)
 	}
 
+	return oyafile.expose()
+}
+
+func (oyafile *Oyafile) expose() error {
+	for _, alias := range oyafile.ExposedAliases {
+		oyafile.Tasks.Expose(alias)
+	}
 	return nil
 }
 

pkg/oyafile/oyafile.go

@@ -27,16 +27,19 @@ type PackReference struct {
 type PackReplacements map[types.ImportPath]string
 
 type Oyafile struct {
-	Dir      string
-	Path     string
-	RootDir  string
-	Shell    string
-	Imports  map[types.Alias]types.ImportPath
-	Tasks    task.Table
-	Values   template.Scope
-	Project  string   // Project is set for root Oyafile.
-	Ignore   []string // Ignore contains directory exclusion rules.
-	Requires []PackReference
+	Dir     string
+	Path    string
+	RootDir string
+	Shell   string
+	Imports map[types.Alias]types.ImportPath
+	Tasks   task.Table
+	// ExposedAliases contains a list of imported packs' aliases that will
+	// be exposed to global scope.
+	ExposedAliases []types.Alias
+	Values         template.Scope
+	Project        string   // Project is set for root Oyafile.
+	Ignore         []string // Ignore contains directory exclusion rules.
+	Requires       []PackReference
 	// Replacements map packs to local paths relative to project root directory for development based on the Replace: directive.
 	Replacements PackReplacements
 	IsBuilt      bool

pkg/oyafile/parsing.go

@@ -13,6 +13,7 @@ import (
 )
 
 const StmtImport = "Import"
+const StmtExpose = "Expose"
 const StmtValues = "Values"
 const StmtProject = "Project"
 const StmtIgnore = "Ignore"
@@ -80,6 +81,8 @@ func parseStatement(name string, value interface{}, o *Oyafile) error {
 		return parseRequire(value, o)
 	case StmtReplace:
 		return parseReplace(value, o)
+	case StmtExpose:
+		return parseExpose(value, o)
 
 	default:
 		taskName := task.Name(name)
@@ -244,3 +247,13 @@ func parseReplace(value interface{}, o *Oyafile) error {
 	return nil
 
 }
+
+func parseExpose(value interface{}, o *Oyafile) error {
+	aliasStr, ok := value.(string)
+	if !ok {
+		return fmt.Errorf("expected an import alias")
+	}
+	alias := types.Alias(aliasStr)
+	o.ExposedAliases = []types.Alias{alias}
+	return nil
+}

pkg/task/mocks.go

@@ -0,0 +1,13 @@
+package task
+
+import (
+	"io"
+
+	"github.com/tooploox/oya/pkg/template"
+)
+
+type MockTask struct{}
+
+func (MockTask) Exec(workDir string, args []string, scope template.Scope, stdout, stderr io.Writer) error {
+	return nil
+}

pkg/task/name.go

@@ -23,6 +23,17 @@ func (n Name) Split() (types.Alias, string) {
 	}
 }
 
+func (n Name) IsAliased(alias types.Alias) bool {
+	// TODO(bilus): Turn Name into a a struct.
+	actualAlias, _ := n.Split()
+	return actualAlias == alias
+}
+
+func (n Name) Unaliased() Name {
+	_, s := n.Split()
+	return Name(s)
+}
+
 func (n Name) IsBuiltIn() bool {
 	firstChar := string(n)[0:1]
 	return firstChar == strings.ToUpper(firstChar)

pkg/task/name_test.go

@@ -28,3 +28,26 @@ func TestName_Split_WithNestedAlias(t *testing.T) {
 	tu.AssertEqual(t, types.Alias("foo.bar"), alias)
 	tu.AssertEqual(t, "zoo", task)
 }
+
+func TestName_IsAliased(t *testing.T) {
+	testCases := []struct {
+		name      task.Name
+		alias     types.Alias
+		isAliased bool
+	}{
+		{task.Name("name"), types.Alias("alias"), false},
+		{task.Name("name").Aliased("alias"), types.Alias("alias"), true},
+		{task.Name("name").Aliased("otherAlias"), types.Alias("alias"), false},
+	}
+
+	for _, tc := range testCases {
+		tu.AssertEqual(t, tc.isAliased, tc.name.IsAliased(tc.alias))
+	}
+}
+
+func TestName_Unaliased(t *testing.T) {
+	globalName := task.Name("name")
+	aliasedName := globalName.Aliased(types.Alias("alias"))
+	tu.AssertEqual(t, globalName, aliasedName.Unaliased())
+	tu.AssertEqual(t, globalName, globalName.Unaliased())
+}

pkg/task/reference.go

@@ -0,0 +1,21 @@
+package task
+
+import (
+	"io"
+
+	"github.com/tooploox/oya/pkg/template"
+)
+
+type reference struct {
+	task Task
+}
+
+func NewReference(task Task) Task {
+	return reference{
+		task: task,
+	}
+}
+
+func (r reference) Exec(workDir string, args []string, scope template.Scope, stdout, stderr io.Writer) error {
+	return r.task.Exec(workDir, args, scope, stdout, stderr)
+}

pkg/task/table.go

@@ -1,8 +1,6 @@
 package task
 
 import (
-	"fmt"
-
 	"github.com/tooploox/oya/pkg/types"
 )
 
@@ -34,12 +32,31 @@ func (tt Table) AddDoc(taskName Name, s string) {
 }
 
 func (tt Table) ImportTasks(alias types.Alias, other Table) {
-	for key, t := range other.tasks {
+	for name, t := range other.tasks {
 		// TODO: Detect if task already set.
-		tt.AddTask(Name(fmt.Sprintf("%v.%v", alias, key)), t)
+		tt.AddTask(Name(name).Aliased(alias), t)
+	}
+}
+
+// Expose copies tasks under an alias to global scope (without the alias)
+// never overriding the existing global tasks.
+func (tt Table) Expose(alias types.Alias) {
+	for name, task := range tt.tasks {
+		if name.IsAliased(alias) {
+			globalName := name.Unaliased()
+			_, ok := tt.LookupTask(globalName)
+			if !ok {
+				tt.addTaskWithMeta(globalName, task, tt.meta[name])
+			}
+		}
 	}
 }
 
+func (tt Table) addTaskWithMeta(name Name, task Task, meta Meta) {
+	tt.tasks[name] = task
+	tt.meta[name] = meta
+}
+
 func (tt Table) ForEach(f func(taskName Name, task Task, meta Meta) error) error {
 	for taskName, task := range tt.tasks {
 		meta := tt.meta[taskName]

pkg/task/table_test.go

@@ -0,0 +1,24 @@
+package task_test
+
+import (
+	"testing"
+
+	"github.com/tooploox/oya/pkg/task"
+	"github.com/tooploox/oya/pkg/types"
+	tu "github.com/tooploox/oya/testutil"
+)
+
+func TestTable_Expose(t *testing.T) {
+	tt := task.NewTable()
+
+	globalName := task.Name("task")
+	aliasedName := globalName.Aliased("alias")
+	tt.AddTask(aliasedName, task.MockTask{})
+
+	tt.Expose(types.Alias("alias"))
+
+	_, ok := tt.LookupTask(aliasedName)
+	tu.AssertTrue(t, ok, "Aliased task not found")
+	_, ok = tt.LookupTask(globalName)
+	tu.AssertTrue(t, ok, "Global task not found")
+}

todo.org

@@ -59,6 +59,11 @@
   - State "CANCELLED"  from "TODO"       [2019-01-25 Fri 10:34] \\
     It's enough to have "install" task by convention in packs and then oya tasks will show it.
   :END:
+* TODO Experiment: exposing tasks
+** TODO PoC
+** TODO Flag for go import
+** TODO Multiple packages?
+** TODO Transient exposure (package exposing another package)
 * TODO Vendoring is only partially implemented
 ** TODO Simplify oya get/vendor (based on Import statements) TBD
 **** Just use Import