recwatch: Remove the ConfigWatch functionality

This is some now dead code which was buggy and badly written. Time to
get rid of unnecessary technical debt so that we can move forward!

hcl/gapi.go

@@ -24,7 +24,6 @@ import (
 
 	"github.com/purpleidea/mgmt/gapi"
 	"github.com/purpleidea/mgmt/pgraph"
-	"github.com/purpleidea/mgmt/recwatch"
 	"github.com/purpleidea/mgmt/resources"
 
 	errwrap "github.com/pkg/errors"
@@ -50,7 +49,6 @@ type GAPI struct {
 	data        gapi.Data
 	wg          sync.WaitGroup
 	closeChan   chan struct{}
-	configWatcher *recwatch.ConfigWatcher
 }
 
 // Cli takes a cli.Context, and returns our GAPI if activated. All arguments
@@ -103,8 +101,6 @@ func (obj *GAPI) Init(d gapi.Data) error {
 	obj.data = d
 	obj.closeChan = make(chan struct{})
 	obj.initialized = true
-	obj.configWatcher = recwatch.NewConfigWatcher()
-
 	return nil
 }
 
@@ -195,7 +191,6 @@ func (obj *GAPI) Close() error {
 		return fmt.Errorf("%s: GAPI is not initialized", Name)
 	}
 
-	obj.configWatcher.Close()
 	close(obj.closeChan)
 	obj.wg.Wait()
 	obj.initialized = false

lang/gapi.go

@@ -25,7 +25,6 @@ import (
 
 	"github.com/purpleidea/mgmt/gapi"
 	"github.com/purpleidea/mgmt/pgraph"
-	"github.com/purpleidea/mgmt/recwatch"
 	"github.com/purpleidea/mgmt/resources"
 
 	multierr "github.com/hashicorp/go-multierror"
@@ -54,7 +53,6 @@ type GAPI struct {
 	initialized bool
 	closeChan   chan struct{}
 	wg          *sync.WaitGroup // sync group for tunnel go routines
-	configWatcher *recwatch.ConfigWatcher
 }
 
 // Cli takes a cli.Context, and returns our GAPI if activated. All arguments
@@ -112,7 +110,6 @@ func (obj *GAPI) Init(data gapi.Data) error {
 	obj.closeChan = make(chan struct{})
 	obj.wg = &sync.WaitGroup{}
 	obj.initialized = true
-	obj.configWatcher = recwatch.NewConfigWatcher()
 	return nil
 }
 
@@ -262,7 +259,6 @@ func (obj *GAPI) Close() error {
 	if !obj.initialized {
 		return fmt.Errorf("%s: GAPI is not initialized", Name)
 	}
-	obj.configWatcher.Close()
 	obj.LangClose() // close lang, esp. if blocked in Stream() wait
 	close(obj.closeChan)
 	obj.wg.Wait()

recwatch/configwatch.go

@@ -1,148 +0,0 @@
-// Mgmt
-// Copyright (C) 2013-2018+ 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 <http://www.gnu.org/licenses/>.
-
-package recwatch
-
-import (
-	"log"
-	"sync"
-)
-
-// ConfigWatcher returns events on a channel anytime one of its files events.
-type ConfigWatcher struct {
-	Flags Flags
-
-	ch        chan string
-	wg        sync.WaitGroup
-	closechan chan struct{}
-	errorchan chan error
-}
-
-// NewConfigWatcher creates a new ConfigWatcher struct.
-func NewConfigWatcher() *ConfigWatcher {
-	return &ConfigWatcher{
-		ch:        make(chan string),
-		closechan: make(chan struct{}),
-		errorchan: make(chan error),
-	}
-}
-
-// Add new file paths to watch for events on.
-func (obj *ConfigWatcher) Add(file ...string) {
-	if len(file) == 0 {
-		return
-	}
-	if len(file) > 1 {
-		for _, f := range file { // add all the files...
-			obj.Add(f) // recurse
-		}
-		return
-	}
-	// otherwise, add the one file passed in...
-	obj.wg.Add(1)
-	go func() {
-		defer obj.wg.Done()
-		ch := obj.ConfigWatch(file[0])
-		for {
-			select {
-			case e, ok := <-ch:
-				if !ok { // channel closed
-					return
-				}
-				if e != nil {
-					obj.errorchan <- e
-					return
-				}
-				select {
-				case obj.ch <- file[0]: // send on channel
-				case <-obj.closechan:
-					return // never mind, close early!
-				}
-				continue
-				// not needed, closes via ConfigWatch() chan close
-				//case <-obj.closechan:
-				//	return
-			}
-		}
-	}()
-}
-
-// Error returns a channel of errors that notifies us of permanent issues.
-func (obj *ConfigWatcher) Error() <-chan error {
-	return obj.errorchan
-}
-
-// Events returns a channel to listen on for file events. It closes when it is
-// emptied after the Close() method is called. You can test for closure with the
-// f, more := <-obj.Events() pattern.
-func (obj *ConfigWatcher) Events() chan string {
-	return obj.ch
-}
-
-// Close shuts down the ConfigWatcher object. It closes the Events channel after
-// all the currently pending events have been emptied.
-func (obj *ConfigWatcher) Close() {
-	if obj.ch == nil {
-		return
-	}
-	close(obj.closechan)
-	obj.wg.Wait() // wait until everyone is done sending on obj.ch
-	//obj.ch <- "" // send finished message
-	close(obj.ch)
-	obj.ch = nil
-	close(obj.errorchan)
-}
-
-// ConfigWatch writes on the channel every time an event is seen for the path.
-func (obj *ConfigWatcher) ConfigWatch(file string) chan error {
-	ch := make(chan error)
-	go func() {
-		recWatcher, err := NewRecWatcher(file, false)
-		if err != nil {
-			ch <- err
-			close(ch)
-			return
-		}
-		recWatcher.Flags = obj.Flags
-		defer recWatcher.Close()
-		for {
-			if obj.Flags.Debug {
-				log.Printf("Watching: %v", file)
-			}
-			select {
-			case event, ok := <-recWatcher.Events():
-				if !ok { // channel is closed
-					close(ch)
-					return
-				}
-				if err := event.Error; err != nil {
-					ch <- err
-					close(ch)
-					return
-				}
-				select {
-				case ch <- nil: // send event!
-				case <-obj.closechan:
-					close(ch)
-					return
-				}
-			}
-		}
-		//close(ch)
-	}()
-	return ch
-}

yamlgraph/gapi.go

@@ -24,7 +24,6 @@ import (
 
 	"github.com/purpleidea/mgmt/gapi"
 	"github.com/purpleidea/mgmt/pgraph"
-	"github.com/purpleidea/mgmt/recwatch"
 	"github.com/purpleidea/mgmt/resources"
 
 	errwrap "github.com/pkg/errors"
@@ -50,7 +49,6 @@ type GAPI struct {
 	initialized bool
 	closeChan   chan struct{}
 	wg          sync.WaitGroup // sync group for tunnel go routines
-	configWatcher *recwatch.ConfigWatcher
 }
 
 // Cli takes a cli.Context, and returns our GAPI if activated. All arguments
@@ -103,7 +101,6 @@ func (obj *GAPI) Init(data gapi.Data) error {
 	obj.data = data // store for later
 	obj.closeChan = make(chan struct{})
 	obj.initialized = true
-	obj.configWatcher = recwatch.NewConfigWatcher()
 	return nil
 }
 
@@ -197,7 +194,6 @@ func (obj *GAPI) Close() error {
 	if !obj.initialized {
 		return fmt.Errorf("%s: GAPI is not initialized", Name)
 	}
-	obj.configWatcher.Close()
 	close(obj.closeChan)
 	obj.wg.Wait()
 	obj.initialized = false // closed = true

yamlgraph2/gapi.go

@@ -24,7 +24,6 @@ import (
 
 	"github.com/purpleidea/mgmt/gapi"
 	"github.com/purpleidea/mgmt/pgraph"
-	"github.com/purpleidea/mgmt/recwatch"
 	"github.com/purpleidea/mgmt/resources"
 
 	errwrap "github.com/pkg/errors"
@@ -50,7 +49,6 @@ type GAPI struct {
 	initialized bool
 	closeChan   chan struct{}
 	wg          sync.WaitGroup // sync group for tunnel go routines
-	configWatcher *recwatch.ConfigWatcher
 }
 
 // Cli takes a cli.Context, and returns our GAPI if activated. All arguments
@@ -103,7 +101,6 @@ func (obj *GAPI) Init(data gapi.Data) error {
 	obj.data = data // store for later
 	obj.closeChan = make(chan struct{})
 	obj.initialized = true
-	obj.configWatcher = recwatch.NewConfigWatcher()
 	return nil
 }
 
@@ -197,7 +194,6 @@ func (obj *GAPI) Close() error {
 	if !obj.initialized {
 		return fmt.Errorf("%s: GAPI is not initialized", Name)
 	}
-	obj.configWatcher.Close()
 	close(obj.closeChan)
 	obj.wg.Wait()
 	obj.initialized = false // closed = true