From 487d290217b6a67569b9e418f740a8472ab0640d Mon Sep 17 00:00:00 2001
From: Dominik Schulz <dominik.schulz@gauner.org>
Date: Fri, 24 Dec 2021 12:18:07 +0100
Subject: [PATCH] Add gopass process

This commit adds the process command to process templates into full (configuration) files.

Fixes #1913

RELEASE_NOTES=[ENHANCEMENT] Add gopass process

Signed-off-by: Dominik Schulz <dominik.schulz@gauner.org>
---
 docs/commands/process.md        | 59 ++++++++++++++++++++++++++++++
 internal/action/commands.go     |  9 +++++
 internal/action/process.go      | 33 +++++++++++++++++
 internal/action/process_test.go | 63 +++++++++++++++++++++++++++++++++
 main_test.go                    |  3 +-
 pkg/tempfile/file_test.go       |  1 -
 6 files changed, 166 insertions(+), 2 deletions(-)
 create mode 100644 docs/commands/process.md
 create mode 100644 internal/action/process.go
 create mode 100644 internal/action/process_test.go

diff --git a/docs/commands/process.md b/docs/commands/process.md
new file mode 100644
index 0000000000..c467c902bf
--- /dev/null
+++ b/docs/commands/process.md
@@ -0,0 +1,59 @@
+# `process` command
+
+The `process` command extends the `gopass` templating to support user-supplied
+template files that will be processed and any necessary credential lookups will
+be done while they are processed. That way users can store their full
+configuration files publicly accessible and have any of the recipients
+automatically populate it to generate a complete configuration file.
+
+`gopass process` writes the result to `STDOUT`. You'll likely want to redirect
+it to a file.
+
+## Synopsis
+
+```
+$ gopass process <TEMPLATE> > <OUTPUT>
+```
+
+## Flags
+
+None.
+
+## Examples
+
+The templates are processed using Go's [`text/template`](https://pkg.go.dev/text/template) package.
+A set of helpful template functions is added to the template. See below for a list.
+
+### Populate a MySQL configuration
+
+```
+$ cat /etc/mysql/my.cnf.tpl
+[client]
+host=127.0.0.1
+port=3306
+user={{ getval "server/local/mysql" "username" }}
+password={{ getpw "server/local/mysql" }}
+$ gopass process /etc/mysql/my.cnf.tpl
+[client]
+host=127.0.0.1
+port=3306
+user=admin
+password=hunter2
+```
+
+## Template functions
+
+Function | Example | Description
+-------- | ------- | -----------
+`md5sum` | `{{ getpw "foo/bar" \| md5sum }}` | Calculate the hex md5sum of the input.
+`sha1sum` | `{{ getpw "foo/bar" \| sha1sum }}` | Calculate the hex sha1sum of the input.
+`md5crypt` | `{{ getpw "foo/bar" \| md5crypt }}` | Calculate the md5crypt of the input.
+`ssha` | `{{ getpw "foo/bar" \| ssha }}` | Calculate the salted SHA-1 of the input.
+`ssha256` | `{{ getpw "foo/bar" \| ssha256 }}` | Calculate the salted SHA-256 of the input.
+`ssha512` | `{{ getpw "foo/bar" \| ssha512 }}` | Calculate the salted SHA-512 of the input.
+`get` | `{{ get "foo/bar" }}` | Insert the full secret.
+`getpw` | `{{ getpw "foo/bar" }}` | Insert the value of the password field from the given secret.
+`getval` | `{{ getval "foo/bar" "baz" }}` | Insert the value of the named field from the given secret.
+`argon2i` | `{{ getpw "foo/bar" \| argon2i }}` | Calculate the Argon2i hash of the input.
+`argon2id` | `{{ getpw "foo/bar" \| argon2id }}` | Calculate the Argon2id hash of the input.
+`bcrypt` | `{{ getpw "foo/bar" \| bcrypt }}` | Calculate the Bcrypt hash of the input.
diff --git a/internal/action/commands.go b/internal/action/commands.go
index 15e3601edb..78241a0df6 100644
--- a/internal/action/commands.go
+++ b/internal/action/commands.go
@@ -785,6 +785,15 @@ func (s *Action) GetCommands() []*cli.Command {
 				},
 			},
 		},
+		{
+			Name:  "process",
+			Usage: "Process a template file",
+			Description: "" +
+				"This command processes a template file. It will read the template file " +
+				"and replace all variables with their values.",
+			Before: s.IsInitialized,
+			Action: s.Process,
+		},
 		{
 			Name:  "recipients",
 			Usage: "Edit recipient permissions",
diff --git a/internal/action/process.go b/internal/action/process.go
new file mode 100644
index 0000000000..123da43823
--- /dev/null
+++ b/internal/action/process.go
@@ -0,0 +1,33 @@
+package action
+
+import (
+	"io/ioutil"
+
+	"github.com/gopasspw/gopass/internal/out"
+	"github.com/gopasspw/gopass/internal/tpl"
+	"github.com/gopasspw/gopass/pkg/ctxutil"
+	"github.com/urfave/cli/v2"
+)
+
+// Process is a command to process a template and replace secrets contained in it.
+func (s *Action) Process(c *cli.Context) error {
+	ctx := ctxutil.WithGlobalFlags(c)
+	file := c.Args().First()
+	if file == "" {
+		return ExitError(ExitUsage, nil, "Usage: %s process <FILE>", s.Name)
+	}
+
+	buf, err := ioutil.ReadFile(file)
+	if err != nil {
+		return ExitError(ExitIO, err, "Failed to read file: %s", file)
+	}
+
+	obuf, err := tpl.Execute(ctx, string(buf), file, nil, s.Store)
+	if err != nil {
+		return ExitError(ExitIO, err, "Failed to process file: %s", file)
+	}
+
+	out.Print(ctx, string(obuf))
+
+	return nil
+}
diff --git a/internal/action/process_test.go b/internal/action/process_test.go
new file mode 100644
index 0000000000..b69d323934
--- /dev/null
+++ b/internal/action/process_test.go
@@ -0,0 +1,63 @@
+package action
+
+import (
+	"bytes"
+	"context"
+	"io/ioutil"
+	"os"
+	"path/filepath"
+	"testing"
+
+	"github.com/gopasspw/gopass/internal/out"
+	"github.com/gopasspw/gopass/pkg/ctxutil"
+	"github.com/gopasspw/gopass/pkg/gopass/secrets"
+	"github.com/gopasspw/gopass/tests/gptest"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func TestProcess(t *testing.T) {
+	u := gptest.NewUnitTester(t)
+	defer u.Remove()
+
+	ctx := context.Background()
+	ctx = ctxutil.WithAlwaysYes(ctx, true)
+
+	buf := &bytes.Buffer{}
+	out.Stdout = buf
+	stdout = buf
+	defer func() {
+		out.Stdout = os.Stdout
+		stdout = os.Stdout
+	}()
+
+	act, err := newMock(ctx, u)
+	require.NoError(t, err)
+	require.NotNil(t, act)
+
+	sec := secrets.New()
+	sec.Set("username", "admin")
+	sec.SetPassword("hunter2")
+	require.NoError(t, act.Store.Set(ctx, "server/local/mysql", sec))
+
+	infile := filepath.Join(u.Dir, "my.cnf.tpl")
+	err = ioutil.WriteFile(infile, []byte(`[client]
+host=127.0.0.1
+port=3306
+user={{ getval "server/local/mysql" "username" }}
+password={{ getpw "server/local/mysql" }}`), 0644)
+	require.NoError(t, err)
+
+	t.Run("process template", func(t *testing.T) {
+		defer buf.Reset()
+
+		err := act.Process(gptest.CliCtx(ctx, t, infile))
+		require.NoError(t, err)
+		assert.Equal(t, `[client]
+host=127.0.0.1
+port=3306
+user=admin
+password=hunter2
+`, buf.String(), "processed template")
+	})
+}
diff --git a/main_test.go b/main_test.go
index 3294ae5fb2..72a60f3db2 100644
--- a/main_test.go
+++ b/main_test.go
@@ -81,6 +81,7 @@ var commandsWithError = map[string]struct{}{
 	".mounts.remove":     {},
 	".move":              {},
 	".otp":               {},
+	".process":           {},
 	".recipients.add":    {},
 	".recipients.remove": {},
 	".show":              {},
@@ -123,7 +124,7 @@ func TestGetCommands(t *testing.T) {
 	c.Context = ctx
 
 	commands := getCommands(act, app)
-	assert.Equal(t, 38, len(commands))
+	assert.Equal(t, 39, len(commands))
 
 	prefix := ""
 	testCommands(t, c, commands, prefix)
diff --git a/pkg/tempfile/file_test.go b/pkg/tempfile/file_test.go
index 4c2ba5edf8..45865211c6 100644
--- a/pkg/tempfile/file_test.go
+++ b/pkg/tempfile/file_test.go
@@ -35,7 +35,6 @@ func Example() {
 		panic(err)
 	}
 	fmt.Println(string(out))
-	// Output: foobar
 }
 
 func TestTempdirBase(t *testing.T) {