pkg/tool/file: support file-related tasks
Updates #39
Change-Id: I0fc36d7414b76e9a741bf3d2616653f96fc462bd
Reviewed-on: https://cue-review.googlesource.com/c/cue/+/1925
Reviewed-by: Marcel van Lohuizen <mpvl@google.com>
diff --git a/pkg/tool/file/file.go b/pkg/tool/file/file.go
new file mode 100644
index 0000000..e5673cc
--- /dev/null
+++ b/pkg/tool/file/file.go
@@ -0,0 +1,98 @@
+// Copyright 2019 CUE Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package file provides file operations for cue tasks.
+package file
+
+import (
+ "io/ioutil"
+ "os"
+ "path/filepath"
+
+ "cuelang.org/go/cue"
+ "cuelang.org/go/internal/task"
+)
+
+func init() {
+ task.Register("tool/file.Read", newReadCmd)
+ task.Register("tool/file.Append", newAppendCmd)
+ task.Register("tool/file.Create", newCreateCmd)
+ task.Register("tool/file.Glob", newGlobCmd)
+}
+
+func newReadCmd(v cue.Value) (task.Runner, error) { return &cmdRead{}, nil }
+func newAppendCmd(v cue.Value) (task.Runner, error) { return &cmdAppend{}, nil }
+func newCreateCmd(v cue.Value) (task.Runner, error) { return &cmdCreate{}, nil }
+func newGlobCmd(v cue.Value) (task.Runner, error) { return &cmdGlob{}, nil }
+
+type cmdRead struct{}
+type cmdAppend struct{}
+type cmdCreate struct{}
+type cmdGlob struct{}
+
+func lookupStr(v cue.Value, str string) string {
+ str, _ = v.Lookup(str).String()
+ return str
+}
+
+func (c *cmdRead) Run(ctx *task.Context, v cue.Value) (res interface{}, err error) {
+ b, err := ioutil.ReadFile(lookupStr(v, "filename"))
+ if err != nil {
+ return nil, err
+ }
+ update := map[string]interface{}{"contents": b}
+
+ switch v.Lookup("contents").IncompleteKind() &^ cue.BottomKind {
+ case cue.BytesKind:
+ case cue.StringKind:
+ update["contents"] = string(b)
+ }
+ return update, nil
+}
+
+func (c *cmdAppend) Run(ctx *task.Context, v cue.Value) (res interface{}, err error) {
+ filename := lookupStr(v, "filename")
+ mode, err := v.Lookup("permissions").Int64()
+ if err != nil {
+ return nil, err
+ }
+
+ f, err := os.OpenFile(filename, os.O_APPEND|os.O_WRONLY, os.FileMode(mode))
+ if err != nil {
+ return nil, err
+ }
+ defer f.Close()
+
+ b, _ := v.Lookup("contents").Bytes()
+ if _, err := f.Write(b); err != nil {
+ return nil, err
+ }
+ return nil, nil
+}
+
+func (c *cmdCreate) Run(ctx *task.Context, v cue.Value) (res interface{}, err error) {
+ filename := lookupStr(v, "filename")
+ mode, err := v.Lookup("permissions").Int64()
+ if err != nil {
+ return nil, err
+ }
+
+ b, _ := v.Lookup("contents").Bytes()
+ return nil, ioutil.WriteFile(filename, b, os.FileMode(mode))
+}
+
+func (c *cmdGlob) Run(ctx *task.Context, v cue.Value) (res interface{}, err error) {
+ m, err := filepath.Glob(lookupStr(v, "glob"))
+ return m, err
+}
