Initial version of a RabbitMQ/AMQP sink

.github/workflows/Release.yml

@@ -44,16 +44,16 @@ jobs:
     # Use dnf to install build dependencies
     - name: Install build dependencies
       run: |
-          wget -q https://go.dev/dl/go1.22.4.linux-amd64.tar.gz --output-document=- | \
+          dnf --assumeyes install \
-          tar --directory=/usr/local --extract --gzip
+              http://mirror.centos.org/centos/8-stream/AppStream/x86_64/os/Packages/golang-1.21.7-1.module_el8+960+4060efbe.x86_64.rpm \
-          export PATH=/usr/local/go/bin:/usr/local/go/pkg/tool/linux_amd64:$PATH
+              http://mirror.centos.org/centos/8-stream/AppStream/x86_64/os/Packages/golang-bin-1.21.7-1.module_el8+960+4060efbe.x86_64.rpm \
-          go version
+              http://mirror.centos.org/centos/8-stream/AppStream/x86_64/os/Packages/golang-src-1.21.7-1.module_el8+960+4060efbe.noarch.rpm \
+              http://mirror.centos.org/centos/8-stream/AppStream/x86_64/os/Packages/go-toolset-1.21.7-1.module_el8+960+4060efbe.x86_64.rpm
 
     - name: RPM build MetricCollector
       id: rpmbuild
       run: |
           git config --global --add safe.directory /__w/cc-metric-collector/cc-metric-collector
-          export PATH=/usr/local/go/bin:/usr/local/go/pkg/tool/linux_amd64:$PATH
           make RPM
 
     # AlmaLinux 8 is a derivate of RedHat Enterprise Linux 8 (UBI8),
@@ -114,16 +114,16 @@ jobs:
     # Use dnf to install build dependencies
     - name: Install build dependencies
       run: |
-          wget -q https://go.dev/dl/go1.22.4.linux-amd64.tar.gz --output-document=- | \
+          dnf --assumeyes --disableplugin=subscription-manager install \
-          tar --directory=/usr/local --extract --gzip
+              http://mirror.centos.org/centos/8-stream/AppStream/x86_64/os/Packages/golang-1.21.7-1.module_el8+960+4060efbe.x86_64.rpm \
-          export PATH=/usr/local/go/bin:/usr/local/go/pkg/tool/linux_amd64:$PATH
+              http://mirror.centos.org/centos/8-stream/AppStream/x86_64/os/Packages/golang-bin-1.21.7-1.module_el8+960+4060efbe.x86_64.rpm \
-          go version
+              http://mirror.centos.org/centos/8-stream/AppStream/x86_64/os/Packages/golang-src-1.21.7-1.module_el8+960+4060efbe.noarch.rpm \
+              http://mirror.centos.org/centos/8-stream/AppStream/x86_64/os/Packages/go-toolset-1.21.7-1.module_el8+960+4060efbe.x86_64.rpm
 
     - name: RPM build MetricCollector
       id: rpmbuild
       run: |
           git config --global --add safe.directory /__w/cc-metric-collector/cc-metric-collector
-          export PATH=/usr/local/go/bin:/usr/local/go/pkg/tool/linux_amd64:$PATH
           make RPM
 
     # See: https://github.com/actions/upload-artifact
@@ -165,7 +165,7 @@ jobs:
     # Use official golang package
     - name: Install Golang
       run: |
-          wget -q https://go.dev/dl/go1.22.4.linux-amd64.tar.gz --output-document=- | \
+          wget -q https://go.dev/dl/go1.21.1.linux-amd64.tar.gz --output-document=- | \
           tar --directory=/usr/local --extract --gzip
           export PATH=/usr/local/go/bin:/usr/local/go/pkg/tool/linux_amd64:$PATH
           go version

.github/workflows/runonce.yml

@@ -91,16 +91,16 @@ jobs:
     # Use dnf to install build dependencies
     - name: Install build dependencies
       run: |
-          wget -q https://go.dev/dl/go1.22.4.linux-amd64.tar.gz --output-document=- | \
+          dnf --assumeyes install \
-          tar --directory=/usr/local --extract --gzip
+              http://mirror.centos.org/centos/8-stream/AppStream/x86_64/os/Packages/golang-1.21.7-1.module_el8+960+4060efbe.x86_64.rpm \
-          export PATH=/usr/local/go/bin:/usr/local/go/pkg/tool/linux_amd64:$PATH
+              http://mirror.centos.org/centos/8-stream/AppStream/x86_64/os/Packages/golang-bin-1.21.7-1.module_el8+960+4060efbe.x86_64.rpm \
-          go version
+              http://mirror.centos.org/centos/8-stream/AppStream/x86_64/os/Packages/golang-src-1.21.7-1.module_el8+960+4060efbe.noarch.rpm \
+              http://mirror.centos.org/centos/8-stream/AppStream/x86_64/os/Packages/go-toolset-1.21.7-1.module_el8+960+4060efbe.x86_64.rpm
 
     - name: RPM build MetricCollector
       id: rpmbuild
       run: |
           git config --global --add safe.directory /__w/cc-metric-collector/cc-metric-collector
-          export PATH=/usr/local/go/bin:/usr/local/go/pkg/tool/linux_amd64:$PATH
           make RPM
 
   #
@@ -129,16 +129,16 @@ jobs:
     # Use dnf to install build dependencies
     - name: Install build dependencies
       run: |
-          wget -q https://go.dev/dl/go1.22.4.linux-amd64.tar.gz --output-document=- | \
+          dnf --assumeyes --disableplugin=subscription-manager install \
-          tar --directory=/usr/local --extract --gzip
+              http://mirror.centos.org/centos/8-stream/AppStream/x86_64/os/Packages/golang-1.21.7-1.module_el8+960+4060efbe.x86_64.rpm \
-          export PATH=/usr/local/go/bin:/usr/local/go/pkg/tool/linux_amd64:$PATH
+              http://mirror.centos.org/centos/8-stream/AppStream/x86_64/os/Packages/golang-bin-1.21.7-1.module_el8+960+4060efbe.x86_64.rpm \
-          go version
+              http://mirror.centos.org/centos/8-stream/AppStream/x86_64/os/Packages/golang-src-1.21.7-1.module_el8+960+4060efbe.noarch.rpm \
+              http://mirror.centos.org/centos/8-stream/AppStream/x86_64/os/Packages/go-toolset-1.21.7-1.module_el8+960+4060efbe.x86_64.rpm
 
     - name: RPM build MetricCollector
       id: rpmbuild
       run: |
           git config --global --add safe.directory /__w/cc-metric-collector/cc-metric-collector
-          export PATH=/usr/local/go/bin:/usr/local/go/pkg/tool/linux_amd64:$PATH
           make RPM
 
   #
@@ -165,7 +165,7 @@ jobs:
     # Use official golang package
     - name: Install Golang
       run: |
-          wget -q https://go.dev/dl/go1.22.4.linux-amd64.tar.gz --output-document=- | \
+          wget -q https://go.dev/dl/go1.21.1.linux-amd64.tar.gz --output-document=- | \
           tar --directory=/usr/local --extract --gzip
           export PATH=/usr/local/go/bin:/usr/local/go/pkg/tool/linux_amd64:$PATH
           go version

collectors/ipmiMetric.go

@@ -12,7 +12,6 @@ import (
 	"strconv"
 	"strings"
 	"time"
-
 	cclog "github.com/ClusterCockpit/cc-metric-collector/pkg/ccLogger"
 	lp "github.com/ClusterCockpit/cc-metric-collector/pkg/ccMetric"
 )
@@ -55,30 +54,15 @@ func (m *IpmiCollector) Init(config json.RawMessage) error {
 	// Check if executables ipmitool or ipmisensors are found
 	p, err := exec.LookPath(m.config.IpmitoolPath)
 	if err == nil {
-		command := exec.Command(p)
+		m.ipmitool = p
-		err := command.Run()
-		if err != nil {
-			cclog.ComponentError(m.name, fmt.Sprintf("Failed to execute %s: %v", p, err.Error()))
-			m.ipmitool = ""
-		} else {
-			m.ipmitool = p
-		}
 	}
 	p, err = exec.LookPath(m.config.IpmisensorsPath)
 	if err == nil {
-		command := exec.Command(p)
+		m.ipmisensors = p
-		err := command.Run()
-		if err != nil {
-			cclog.ComponentError(m.name, fmt.Sprintf("Failed to execute %s: %v", p, err.Error()))
-			m.ipmisensors = ""
-		} else {
-			m.ipmisensors = p
-		}
 	}
 	if len(m.ipmitool) == 0 && len(m.ipmisensors) == 0 {
-		return errors.New("no usable IPMI reader found")
+		return errors.New("no IPMI reader found")
 	}
-
 	m.init = true
 	return nil
 }
@@ -135,8 +119,8 @@ func (m *IpmiCollector) readIpmiTool(cmd string, output chan lp.CCMetric) {
 		cclog.ComponentError(
 			m.name,
 			fmt.Sprintf("readIpmiTool(): Failed to wait for the end of command \"%s\": %v\n", command.String(), err),
+			fmt.Sprintf("readIpmiTool(): command stderr: \"%s\"\n", string(errMsg)),
 		)
-		cclog.ComponentError(m.name, fmt.Sprintf("readIpmiTool(): command stderr: \"%s\"\n", strings.TrimSpace(string(errMsg))))
 		return
 	}
 }

docs/configuration.md

@@ -12,8 +12,8 @@ The global file contains the paths to the other four files and some global optio
   "collectors" : "collectors.json",
   "receivers" : "receivers.json",
   "router" : "router.json",
-  "interval": "10s",
+  "interval": 10,
-  "duration": "1s"
+  "duration": 1
 }
 ```
 

receivers/natsReceiver.go

@@ -4,7 +4,6 @@ import (
 	"encoding/json"
 	"errors"
 	"fmt"
-	"os"
 	"time"
 
 	cclog "github.com/ClusterCockpit/cc-metric-collector/pkg/ccLogger"
@@ -14,13 +13,10 @@ import (
 )
 
 type NatsReceiverConfig struct {
-	Type     string `json:"type"`
+	Type    string `json:"type"`
-	Addr     string `json:"address"`
+	Addr    string `json:"address"`
-	Port     string `json:"port"`
+	Port    string `json:"port"`
-	Subject  string `json:"subject"`
+	Subject string `json:"subject"`
-	User     string `json:"user,omitempty"`
-	Password string `json:"password,omitempty"`
-	NkeyFile string `json:"nkey_file,omitempty"`
 }
 
 type NatsReceiver struct {
@@ -113,7 +109,6 @@ func (r *NatsReceiver) Close() {
 
 // NewNatsReceiver creates a new Receiver which subscribes to messages from a NATS server
 func NewNatsReceiver(name string, config json.RawMessage) (Receiver, error) {
-	var uinfo nats.Option = nil
 	r := new(NatsReceiver)
 	r.name = fmt.Sprintf("NatsReceiver(%s)", name)
 
@@ -138,22 +133,10 @@ func NewNatsReceiver(name string, config json.RawMessage) (Receiver, error) {
 		"source": r.name,
 	}
 
-	if len(r.config.User) > 0 && len(r.config.Password) > 0 {
-		uinfo = nats.UserInfo(r.config.User, r.config.Password)
-	} else if len(r.config.NkeyFile) > 0 {
-		_, err := os.Stat(r.config.NkeyFile)
-		if err == nil {
-			uinfo = nats.UserCredentials(r.config.NkeyFile)
-		} else {
-			cclog.ComponentError(r.name, "NKEY file", r.config.NkeyFile, "does not exist: %v", err.Error())
-			return nil, err
-		}
-	}
-
 	// Connect to NATS server
 	url := fmt.Sprintf("nats://%s:%s", r.config.Addr, r.config.Port)
 	cclog.ComponentDebug(r.name, "NewNatsReceiver", url, "Subject", r.config.Subject)
-	if nc, err := nats.Connect(url, uinfo); err == nil {
+	if nc, err := nats.Connect(url); err == nil {
 		r.nc = nc
 	} else {
 		r.nc = nil

receivers/natsReceiver.md

@@ -10,10 +10,7 @@ The `nats` receiver can be used receive metrics from the NATS network. The `nats
     "type": "nats",
     "address" : "nats-server.example.org",
     "port" : "4222",
-    "subject" : "subject",
+    "subject" : "subject"
-    "user": "natsuser",
-    "password": "natssecret",
-    "nkey_file": "/path/to/nkey_file"
   }
 }
 ```
@@ -22,9 +19,6 @@ The `nats` receiver can be used receive metrics from the NATS network. The `nats
 - `address`: Address of the NATS control server
 - `port`: Port of the NATS control server
 - `subject`: Subscribes to this subject and receive metrics
-- `user`: Connect to nats using this user
-- `password`: Connect to nats using this password
-- `nkey_file`: Path to credentials file with NKEY
 
 ### Debugging
 

sinks/README.md

@@ -17,7 +17,7 @@ This folder contains the SinkManager and sink implementations for the cc-metric-
 The configuration file for the sinks is a list of configurations. The `type` field in each specifies which sink to initialize.
 
 ```json
-{
+[
   "mystdout" : {
     "type" : "stdout",
     "meta_as_tags" : [
@@ -31,7 +31,7 @@ The configuration file for the sinks is a list of configurations. The `type` fie
     "database" : "ccmetric",
     "password" : "<jwt token>"
   }
-}
+]
 ```
 
 

sinks/amqpSink.go

@@ -0,0 +1,352 @@
+package sinks
+
+import (
+	"bytes"
+	"context"
+	"encoding/json"
+	"fmt"
+	"net"
+	"sync"
+	"time"
+
+	cclog "github.com/ClusterCockpit/cc-metric-collector/pkg/ccLogger"
+	lp "github.com/ClusterCockpit/cc-metric-collector/pkg/ccMetric"
+	influx "github.com/influxdata/line-protocol/v2/lineprotocol"
+	amqp "github.com/rabbitmq/amqp091-go"
+	"golang.org/x/exp/slices"
+)
+
+type AmqpSinkConfig struct {
+	// defines JSON tags for 'type' and 'meta_as_tags' (string list)
+	// See: metricSink.go
+	defaultSinkConfig
+	// Additional config options, for AmqpSink
+	QueueName string `json:"queue_name"`
+	// Maximum number of points sent to server in single request.
+	// Default: 1000
+	BatchSize int `json:"batch_size,omitempty"`
+
+	// Time interval for delayed sending of metrics.
+	// If the buffers are already filled before the end of this interval,
+	// the metrics are sent without further delay.
+	// Default: 1s
+	FlushInterval string `json:"flush_delay,omitempty"`
+	flushDelay    time.Duration
+
+	Hostname       string `json:"hostname"`
+	Port           int    `json:"port"`
+	PublishTimeout string `json:"publish_timeout,omitempty"`
+	publishTimeout time.Duration
+	Username       string `json:"username,omitempty"`
+	Password       string `json:"password,omitempty"`
+}
+
+type AmqpSink struct {
+	// declares elements 	'name' and 'meta_as_tags' (string to bool map!)
+	sink
+	config AmqpSinkConfig // entry point to the AmqpSinkConfig
+	// influx line protocol encoder
+	encoder influx.Encoder
+	// number of records stored in the encoder
+	numRecordsInEncoder int
+	// List of tags and meta data tags which should be used as tags
+	extended_tag_list []key_value_pair
+	// Flush() runs in another goroutine and accesses the influx line protocol encoder,
+	// so this encoderLock has to protect the encoder and numRecordsInEncoder
+	encoderLock sync.Mutex
+
+	// timer to run Flush()
+	flushTimer *time.Timer
+	// Lock to assure that only one timer is running at a time
+	timerLock sync.Mutex
+
+	// WaitGroup to ensure only one send operation is running at a time
+	sendWaitGroup sync.WaitGroup
+
+	client  *amqp.Connection
+	channel *amqp.Channel
+	queue   amqp.Queue
+}
+
+// Implement functions required for Sink interface
+// Write(...), Flush(), Close()
+// See: metricSink.go
+
+// Code to submit a single CCMetric to the sink
+func (s *AmqpSink) Write(m lp.CCMetric) error {
+
+	// Lock for encoder usage
+	s.encoderLock.Lock()
+
+	// Encode measurement name
+	s.encoder.StartLine(m.Name())
+
+	// copy tags and meta data which should be used as tags
+	s.extended_tag_list = s.extended_tag_list[:0]
+	for key, value := range m.Tags() {
+		s.extended_tag_list =
+			append(
+				s.extended_tag_list,
+				key_value_pair{
+					key:   key,
+					value: value,
+				},
+			)
+	}
+	for _, key := range s.config.MetaAsTags {
+		if value, ok := m.GetMeta(key); ok {
+			s.extended_tag_list =
+				append(
+					s.extended_tag_list,
+					key_value_pair{
+						key:   key,
+						value: value,
+					},
+				)
+		}
+	}
+
+	// Encode tags (they musts be in lexical order)
+	slices.SortFunc(
+		s.extended_tag_list,
+		func(a key_value_pair, b key_value_pair) int {
+			if a.key < b.key {
+				return -1
+			}
+			if a.key > b.key {
+				return +1
+			}
+			return 0
+		},
+	)
+	for i := range s.extended_tag_list {
+		s.encoder.AddTag(
+			s.extended_tag_list[i].key,
+			s.extended_tag_list[i].value,
+		)
+	}
+
+	// Encode fields
+	for key, value := range m.Fields() {
+		s.encoder.AddField(key, influx.MustNewValue(value))
+	}
+
+	// Encode time stamp
+	s.encoder.EndLine(m.Time())
+
+	// Check for encoder errors
+	if err := s.encoder.Err(); err != nil {
+		// Unlock encoder usage
+		s.encoderLock.Unlock()
+
+		return fmt.Errorf("encoding failed: %v", err)
+	}
+	s.numRecordsInEncoder++
+
+	if s.config.flushDelay == 0 {
+		// Unlock encoder usage
+		s.encoderLock.Unlock()
+
+		// Directly flush if no flush delay is configured
+		return s.Flush()
+	} else if s.numRecordsInEncoder == s.config.BatchSize {
+		// Unlock encoder usage
+		s.encoderLock.Unlock()
+
+		// Stop flush timer
+		if s.flushTimer != nil {
+			if ok := s.flushTimer.Stop(); ok {
+				cclog.ComponentDebug(s.name, "Write(): Stopped flush timer. Batch size limit reached before flush delay")
+				s.timerLock.Unlock()
+			}
+		}
+
+		// Flush if batch size is reached
+		return s.Flush()
+	} else if s.timerLock.TryLock() {
+
+		// Setup flush timer when flush delay is configured
+		// and no other timer is already running
+		if s.flushTimer != nil {
+
+			// Restarting existing flush timer
+			cclog.ComponentDebug(s.name, "Write(): Restarting flush timer")
+			s.flushTimer.Reset(s.config.flushDelay)
+		} else {
+
+			// Creating and starting flush timer
+			cclog.ComponentDebug(s.name, "Write(): Starting new flush timer")
+			s.flushTimer = time.AfterFunc(
+				s.config.flushDelay,
+				func() {
+					defer s.timerLock.Unlock()
+					cclog.ComponentDebug(s.name, "Starting flush triggered by flush timer")
+					if err := s.Flush(); err != nil {
+						cclog.ComponentError(s.name, "Flush triggered by flush timer: flush failed:", err)
+					}
+				})
+		}
+	}
+
+	// Unlock encoder usage
+	s.encoderLock.Unlock()
+	return nil
+}
+
+// If the sink uses batched sends internally, you can tell to flush its buffers
+func (s *AmqpSink) Flush() error {
+
+	// Lock for encoder usage
+	// Own lock for as short as possible: the time it takes to clone the buffer.
+	s.encoderLock.Lock()
+
+	buf := slices.Clone(s.encoder.Bytes())
+	numRecordsInBuf := s.numRecordsInEncoder
+	s.encoder.Reset()
+	s.numRecordsInEncoder = 0
+
+	// Unlock encoder usage
+	s.encoderLock.Unlock()
+
+	if len(buf) == 0 {
+		return nil
+	}
+
+	cclog.ComponentDebug(s.name, "Flush(): Flushing", numRecordsInBuf, "metrics")
+
+	// Asynchron send of encoder metrics
+	s.sendWaitGroup.Add(1)
+	go func() {
+		defer s.sendWaitGroup.Done()
+		//startTime := time.Now()
+		ctx, cancel := context.WithTimeout(context.Background(), s.config.flushDelay)
+		defer cancel()
+		err := s.channel.PublishWithContext(ctx, "", s.queue.Name, false, false, amqp.Publishing{
+			ContentType: "text/plain",
+			Body:        buf,
+		})
+		if err != nil {
+			cclog.ComponentError(s.name, err.Error())
+		}
+	}()
+	return nil
+}
+
+// Close sink: close network connection, close files, close libraries, ...
+func (s *AmqpSink) Close() {
+
+	cclog.ComponentDebug(s.name, "CLOSE")
+
+	// Stop existing timer and immediately flush
+	if s.flushTimer != nil {
+		if ok := s.flushTimer.Stop(); ok {
+			s.timerLock.Unlock()
+		}
+	}
+
+	// Flush
+	if err := s.Flush(); err != nil {
+		cclog.ComponentError(s.name, "Close():", "Flush failed:", err)
+	}
+
+	// Wait for send operations to finish
+	s.sendWaitGroup.Wait()
+
+	s.client.Close()
+	s.client = nil
+}
+
+// New function to create a new instance of the sink
+// Initialize the sink by giving it a name and reading in the config JSON
+func NewAmqpSink(name string, config json.RawMessage) (Sink, error) {
+	s := new(AmqpSink)
+
+	// Set name of sampleSink
+	// The name should be chosen in such a way that different instances of AmqpSink can be distinguished
+	s.name = fmt.Sprintf("AmqpSink(%s)", name) // Always specify a name here
+
+	// Set defaults in s.config
+	// Allow overwriting these defaults by reading config JSON
+
+	s.config.PublishTimeout = "4s"
+	s.config.publishTimeout = time.Duration(4) * time.Second
+	s.config.Hostname = "localhost"
+	s.config.Port = 1883
+
+	// Read in the config JSON
+	if len(config) > 0 {
+		d := json.NewDecoder(bytes.NewReader(config))
+		d.DisallowUnknownFields()
+		if err := d.Decode(&s.config); err != nil {
+			cclog.ComponentError(s.name, "Error reading config:", err.Error())
+			return nil, err
+		}
+	}
+
+	// Create lookup map to use meta infos as tags in the output metric
+	s.meta_as_tags = make(map[string]bool)
+	for _, k := range s.config.MetaAsTags {
+		s.meta_as_tags[k] = true
+	}
+
+	// Check if all required fields in the config are set
+	// E.g. use 'len(s.config.Option) > 0' for string settings
+	if t, err := time.ParseDuration(s.config.PublishTimeout); err == nil {
+		s.config.publishTimeout = t
+	} else {
+		err := fmt.Errorf("to parse duration for PublishTimeout: %s", s.config.PublishTimeout)
+		cclog.ComponentError(s.name, err.Error())
+		return nil, err
+	}
+	if t, err := time.ParseDuration(s.config.FlushInterval); err == nil {
+		s.config.flushDelay = t
+	} else {
+		err := fmt.Errorf("to parse duration for FlushInterval: %s", s.config.FlushInterval)
+		cclog.ComponentError(s.name, err.Error())
+		return nil, err
+	}
+
+	url := net.JoinHostPort(s.config.Hostname, fmt.Sprintf("%d", s.config.Port))
+	userpart := ""
+	if len(s.config.Username) > 0 {
+		userpart = s.config.Username
+		if len(s.config.Password) > 0 {
+			userpart += ":" + s.config.Password
+		}
+		userpart += "@"
+	}
+	url = fmt.Sprintf("amqp://%s%s", userpart, url)
+
+	// Establish connection to the server, library, ...
+	// Check required files exist and lookup path(s) of executable(s)
+	c, err := amqp.Dial(url)
+	if err != nil {
+		return nil, err
+	}
+	s.client = c
+
+	ch, err := c.Channel()
+	if err != nil {
+		s.client.Close()
+		return nil, err
+	}
+	s.channel = ch
+
+	q, err := ch.QueueDeclare(
+		s.config.QueueName, // name
+		false,              // durable
+		false,              // delete when unused
+		false,              // exclusive
+		false,              // no-wait
+		nil,                // arguments
+	)
+	if err != nil {
+		s.channel.Close()
+		s.client.Close()
+		return nil, err
+	}
+	s.queue = q
+
+	// Return (nil, meaningful error message) in case of errors
+	return s, nil
+}

sinks/amqpSink.md

@@ -0,0 +1,33 @@
+## `amqp` sink
+
+The `amqp` sink publishes all metrics into a RabbitMQ network. The publishing key is the queue name in the configuration file
+
+### Configuration structure
+
+```json
+{
+  "<name>": {
+    "type": "amqp",
+    "queue_name" : "myqueue",
+    "batch_size" : 1000,
+    "flush_delay": "4s",
+    "publish_timeout": "1s",
+    "host": "dbhost.example.com",
+    "port": 5672,
+    "username": "exampleuser",
+    "password" : "examplepw",
+    "meta_as_tags" : [],
+  }
+}
+```
+
+- `type`: makes the sink an `amqp` sink, also `rabbitmq` is allowed as alias
+- `queue_name`: All metrics are published to this queue
+- `host`: Hostname of the RabbitMQ server
+- `port`: Port number of the RabbitMQ server
+- `username`: Username for basic authentication
+- `password`: Password for basic authentication
+- `meta_as_tags`: print all meta information as tags in the output (optional)
+- `publish_timeout`: Timeout for each publication operation (default `1s`)
+- `flush_delay`: Group metrics coming in to a single batch (default `4s`)
+- `batch_size`: Maximal batch size. If `batch_size` is reached before the end of `flush_delay`, the metrics are sent without further delay (default: `1000`)

sinks/natsSink.go

@@ -5,7 +5,6 @@ import (
 	"encoding/json"
 	"errors"
 	"fmt"
-	"os"
 	"sync"
 	"time"
 
@@ -23,7 +22,6 @@ type NatsSinkConfig struct {
 	User       string `json:"user,omitempty"`
 	Password   string `json:"password,omitempty"`
 	FlushDelay string `json:"flush_delay,omitempty"`
-	NkeyFile   string `json:"nkey_file,omitempty"`
 }
 
 type NatsSink struct {
@@ -44,13 +42,6 @@ func (s *NatsSink) connect() error {
 	var nc *nats.Conn
 	if len(s.config.User) > 0 && len(s.config.Password) > 0 {
 		uinfo = nats.UserInfo(s.config.User, s.config.Password)
-	} else if len(s.config.NkeyFile) > 0 {
-		if _, err := os.Stat(s.config.NkeyFile); err == nil {
-			uinfo = nats.UserCredentials(s.config.NkeyFile)
-		} else {
-			cclog.ComponentError(s.name, "NKEY file", s.config.NkeyFile, "does not exist: %v", err.Error())
-			return err
-		}
 	}
 	uri := fmt.Sprintf("nats://%s:%s", s.config.Host, s.config.Port)
 	cclog.ComponentDebug(s.name, "Connect to", uri)

sinks/natsSink.md

@@ -13,7 +13,6 @@ The `nats` sink publishes all metrics into a NATS network. The publishing key is
     "port": "4222",
     "user": "exampleuser",
     "password" : "examplepw",
-    "nkey_file": "/path/to/nkey_file",
     "meta_as_tags" : [],
   }
 }
@@ -26,4 +25,3 @@ The `nats` sink publishes all metrics into a NATS network. The publishing key is
 - `user`: Username for basic authentication
 - `password`: Password for basic authentication
 - `meta_as_tags`: print all meta information as tags in the output (optional)
-- `nkey_file`: Path to credentials file with NKEY

sinks/sinkManager.go

@@ -21,6 +21,8 @@ var AvailableSinks = map[string]func(name string, config json.RawMessage) (Sink,
 	"influxdb":    NewInfluxSink,
 	"influxasync": NewInfluxAsyncSink,
 	"http":        NewHttpSink,
+	"amqp":        NewAmqpSink,
+	"rabbitmq":    NewAmqpSink,
 }
 
 // Metric collector manager data structure