Refacture structure proposal. (#1793)

command/pipe-main.go

@@ -0,0 +1,111 @@
+/*
+ * Minio Client, (C) 2015 Minio, Inc.
+ *
+ * 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 command
+
+import (
+	"os"
+	"syscall"
+
+	"github.com/minio/cli"
+	"github.com/minio/minio/pkg/probe"
+)
+
+var (
+	pipeFlags = []cli.Flag{
+		cli.BoolFlag{
+			Name:  "help, h",
+			Usage: "Help of pipe.",
+		},
+	}
+)
+
+// Display contents of a file.
+var pipeCmd = cli.Command{
+	Name:   "pipe",
+	Usage:  "Write contents of stdin to one target. When no target is specified, it writes to stdout.",
+	Action: mainPipe,
+	Flags:  append(pipeFlags, globalFlags...),
+	CustomHelpTemplate: `NAME:
+   mc {{.Name}} - {{.Usage}}
+
+USAGE:
+   mc {{.Name}} [FLAGS] [TARGET]
+
+FLAGS:
+  {{range .Flags}}{{.}}
+  {{end}}
+EXAMPLES:
+   1. Write contents of stdin to a file on local filesystem.
+      $ mc {{.Name}} /tmp/hello-world.go
+
+   2. Write contents of stdin to an object on Amazon S3 cloud storage.
+      $ mc {{.Name}} s3/personalbuck/meeting-notes.txt
+
+   3. Copy an ISO image to an object on Amazon S3 cloud storage.
+      $ cat debian-8.2.iso | mc {{.Name}} s3/ferenginar/gnuos.iso
+
+   4. Stream MySQL database dump to Amazon S3 directly.
+      $ mysqldump -u root -p ******* accountsdb | mc {{.Name}} s3/ferenginar/backups/accountsdb-oct-9-2015.sql
+`,
+}
+
+func pipe(targetURL string) *probe.Error {
+	if targetURL == "" {
+		// When no target is specified, pipe cat's stdin to stdout.
+		return catOut(os.Stdin).Trace()
+	}
+
+	// Stream from stdin to multiple objects until EOF.
+	// Ignore size, since os.Stat() would not return proper size all the time
+	// for local filesystem for example /proc files.
+	_, err := putTargetStream(targetURL, os.Stdin, -1)
+	// TODO: See if this check is necessary.
+	switch e := err.ToGoError().(type) {
+	case *os.PathError:
+		if e.Err == syscall.EPIPE {
+			// stdin closed by the user. Gracefully exit.
+			return nil
+		}
+	}
+	return err.Trace(targetURL)
+}
+
+// check pipe input arguments.
+func checkPipeSyntax(ctx *cli.Context) {
+	if len(ctx.Args()) > 1 {
+		cli.ShowCommandHelpAndExit(ctx, "pipe", 1) // last argument is exit code.
+	}
+}
+
+// mainPipe is the main entry point for pipe command.
+func mainPipe(ctx *cli.Context) {
+	// Set global flags from context.
+	setGlobalsFromContext(ctx)
+
+	// validate pipe input arguments.
+	checkPipeSyntax(ctx)
+
+	if len(ctx.Args()) == 0 {
+		err := pipe("")
+		fatalIf(err.Trace("stdout"), "Unable to write to one or more targets.")
+	} else {
+		// extract URLs.
+		URLs := ctx.Args()
+		err := pipe(URLs[0])
+		fatalIf(err.Trace(URLs[0]), "Unable to write to one or more targets.")
+	}
+}