gapi: Bring back puppet and langpuppet

This reverts commit e767655ede.

In addition, it applies required changes to function with the new CLI backend.

puppet/puppet.go

@@ -0,0 +1,160 @@
+// Mgmt
+// Copyright (C) 2013-2024+ James Shubin and the project contributors
+// Written by James Shubin <james@shubin.ca> and the project contributors
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program.  If not, see <https://www.gnu.org/licenses/>.
+//
+// Additional permission under GNU GPL version 3 section 7
+//
+// If you modify this program, or any covered work, by linking or combining it
+// with embedded mcl code and modules (and that the embedded mcl code and
+// modules which link with this program, contain a copy of their source code in
+// the authoritative form) containing parts covered by the terms of any other
+// license, the licensors of this program grant you additional permission to
+// convey the resulting work. Furthermore, the licensors of this program grant
+// the original author, James Shubin, additional permission to update this
+// additional permission if he deems it necessary to achieve the goals of this
+// additional permission.
+
+// Package puppet provides the integration entrypoint for the puppet language.
+package puppet
+
+import (
+	"bufio"
+	"fmt"
+	"io"
+	"os/exec"
+	"strconv"
+	"strings"
+
+	"github.com/purpleidea/mgmt/util/errwrap"
+	"github.com/purpleidea/mgmt/yamlgraph"
+)
+
+const (
+	// PuppetYAMLBufferSize is the maximum buffer size for the yaml input data
+	PuppetYAMLBufferSize = 65535
+)
+
+func (obj *GAPI) runPuppetCommand(cmd *exec.Cmd) ([]byte, error) {
+	if obj.data.Debug {
+		obj.data.Logf("running command: %v", cmd)
+	}
+
+	stdout, err := cmd.StdoutPipe()
+	if err != nil {
+		return nil, errwrap.Wrapf(err, "error opening pipe to puppet command")
+	}
+	stderr, err := cmd.StderrPipe()
+	if err != nil {
+		return nil, errwrap.Wrapf(err, "error opening error pipe to puppet command")
+	}
+
+	if err := cmd.Start(); err != nil {
+		return nil, errwrap.Wrapf(err, "error starting puppet command")
+	}
+
+	// XXX: the current implementation is likely prone to fail
+	// as soon as the YAML data overflows the buffer.
+	data := make([]byte, PuppetYAMLBufferSize)
+	var result []byte
+	for err == nil {
+		var count int
+		count, err = stdout.Read(data)
+		if err != nil && err != io.EOF {
+			obj.data.Logf("error reading YAML data from puppet: %v", err)
+			return nil, err
+		}
+		// Slicing down to the number of actual bytes is important, the YAML parser
+		// will choke on an oversized slice. http://stackoverflow.com/a/33726617/3356612
+		result = append(result, data[0:count]...)
+	}
+	if obj.data.Debug {
+		obj.data.Logf("read %d bytes of data from puppet", len(result))
+	}
+	for scanner := bufio.NewScanner(stderr); scanner.Scan(); {
+		obj.data.Logf("(output) %v", scanner.Text())
+	}
+	if err := cmd.Wait(); err != nil {
+		return nil, errwrap.Wrapf(err, "error waiting for puppet command to complete")
+	}
+
+	return result, nil
+}
+
+// ParseConfigFromPuppet returns the graph configuration structure from the mode
+// and input values, including possibly some file and directory paths.
+func (obj *GAPI) ParseConfigFromPuppet() (*yamlgraph.GraphConfig, error) {
+	var args []string
+	switch obj.Mode {
+	case "agent":
+		args = []string{"mgmtgraph", "print"}
+	case "file":
+		args = []string{"mgmtgraph", "print", "--manifest", obj.puppetFile}
+	case "string":
+		args = []string{"mgmtgraph", "print", "--code", obj.puppetString}
+	case "dir":
+		// TODO: run the code from the obj.puppetDir directory path
+		return nil, fmt.Errorf("not implemented") // XXX: not implemented
+	default:
+		panic(fmt.Sprintf("%s: unhandled case: %s", Name, obj.Mode))
+	}
+
+	if obj.puppetConf != "" {
+		args = append(args, "--config="+obj.puppetConf)
+	}
+
+	cmd := exec.Command("puppet", args...)
+
+	obj.data.Logf("launching translator")
+
+	var config yamlgraph.GraphConfig
+	if data, err := obj.runPuppetCommand(cmd); err != nil {
+		return nil, errwrap.Wrapf(err, "could not run puppet command")
+	} else if err := config.Parse(data); err != nil {
+		return nil, errwrap.Wrapf(err, "could not parse YAML output")
+	}
+
+	return &config, nil
+}
+
+// refreshInterval returns the graph refresh interval from the puppet
+// configuration.
+func (obj *GAPI) refreshInterval() int {
+	if obj.data.Debug {
+		obj.data.Logf("determining graph refresh interval")
+	}
+	var cmd *exec.Cmd
+	if obj.puppetConf != "" {
+		cmd = exec.Command("puppet", "config", "print", "runinterval", "--config", obj.puppetConf)
+	} else {
+		cmd = exec.Command("puppet", "config", "print", "runinterval")
+	}
+
+	obj.data.Logf("inspecting runinterval configuration")
+
+	interval := 1800
+	data, err := obj.runPuppetCommand(cmd)
+	if err != nil {
+		obj.data.Logf("could not determine configured run interval (%v), using default of %v", err, interval)
+		return interval
+	}
+	result, err := strconv.ParseInt(strings.TrimSpace(string(data)), 10, 0)
+	if err != nil {
+		obj.data.Logf("error reading numeric runinterval value (%v), using default of %v", err, interval)
+		return interval
+	}
+
+	return int(result)
+}