diff --git a/CHANGELOG.md b/CHANGELOG.md
index 21839b50b378f8e5e2399248ac35b970bae8db0c..68893bf6ca135eb7e6a09742461ec8a787d9686b 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -44,6 +44,7 @@
- [#3455](https://github.com/influxdata/telegraf/pull/3455): Add tag/integer pair for result to net_response.
- [#4010](https://github.com/influxdata/telegraf/pull/3455): Add application_insights output plugin.
- [#4167](https://github.com/influxdata/telegraf/pull/4167): Added several important elasticsearch cluster health metrics.
+- [#4094](https://github.com/influxdata/telegraf/pull/4094): Add batch mode to mqtt output.
### Bugfixes
diff --git a/etc/telegraf.conf b/etc/telegraf.conf
index ef0f95cafc854b07e5246b6df57c89b0793103af..1e7e8bed1f6fa549ec5fde57a68e6083439825e4 100644
--- a/etc/telegraf.conf
+++ b/etc/telegraf.conf
@@ -198,6 +198,26 @@
# data_format = "influx"
+# # Send metrics to Azure Application Insights
+# [[outputs.application_insights]]
+# ## Instrumentation key of the Application Insights resource.
+# instrumentation_key = "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxx"
+#
+# ## Timeout for closing (default: 5s).
+# # timeout = "5s"
+#
+# ## Enable additional diagnostic logging.
+# # enable_diagnosic_logging = false
+#
+# ## Context Tag Sources add Application Insights context tags to a tag value.
+# ##
+# ## For list of allowed context tag keys see:
+# ## https://github.com/Microsoft/ApplicationInsights-Go/blob/master/appinsights/contracts/contexttagkeys.go
+# # [outputs.application_insights.context_tag_sources]
+# # "ai.cloud.role" = "kubernetes_container_name"
+# # "ai.cloud.roleInstance" = "kubernetes_pod_name"
+
+
# # Configuration for AWS CloudWatch output.
# [[outputs.cloudwatch]]
# ## Amazon REGION
@@ -341,6 +361,40 @@
# servers = ["127.0.0.1:12201", "192.168.1.1:12201"]
+# # A plugin that can transmit metrics over HTTP
+# [[outputs.http]]
+# ## URL is the address to send metrics to
+# url = "http://127.0.0.1:8080/metric"
+#
+# ## Timeout for HTTP message
+# # timeout = "5s"
+#
+# ## HTTP method, one of: "POST" or "PUT"
+# # method = "POST"
+#
+# ## HTTP Basic Auth credentials
+# # username = "username"
+# # password = "pa$$word"
+#
+# ## Additional HTTP headers
+# # [outputs.http.headers]
+# # # Should be set to "application/json" for json data_format
+# # Content-Type = "text/plain; charset=utf-8"
+#
+# ## Optional TLS Config
+# # tls_ca = "/etc/telegraf/ca.pem"
+# # tls_cert = "/etc/telegraf/cert.pem"
+# # tls_key = "/etc/telegraf/key.pem"
+# ## Use TLS but skip chain & host verification
+# # insecure_skip_verify = false
+#
+# ## Data format to output.
+# ## Each data format has it's own unique set of configuration options, read
+# ## more about them here:
+# ## https://github.com/influxdata/telegraf/blob/master/docs/DATA_FORMATS_OUTPUT.md
+# # data_format = "influx"
+
+
# # Configuration for sending metrics to an Instrumental project
# [[outputs.instrumental]]
# ## Project API Token (required)
@@ -527,16 +581,22 @@
# ## ex: prefix/web01.example.com/mem
# topic_prefix = "telegraf"
#
+# ## QoS policy for messages
+# ## 0 = at most once
+# ## 1 = at least once
+# ## 2 = exactly once
+# # qos = 2
+#
# ## username and password to connect MQTT server.
# # username = "telegraf"
# # password = "metricsmetricsmetricsmetrics"
#
-# ## Timeout for write operations. default: 5s
-# # timeout = "5s"
-#
# ## client ID, if not set a random ID is generated
# # client_id = ""
#
+# ## Timeout for write operations. default: 5s
+# # timeout = "5s"
+#
# ## Optional TLS Config
# # tls_ca = "/etc/telegraf/ca.pem"
# # tls_cert = "/etc/telegraf/cert.pem"
@@ -544,6 +604,10 @@
# ## Use TLS but skip chain & host verification
# # insecure_skip_verify = false
#
+# ## When true, metrics will be sent in one MQTT message per flush. Otherwise,
+# ## metrics are written one metric per MQTT message.
+# # batch = false
+#
# ## Data format to output.
# ## Each data format has its own unique set of configuration options, read
# ## more about them here:
@@ -1169,6 +1233,11 @@
# # tls_key = "/etc/telegraf/key.pem"
# ## Use TLS but skip chain & host verification
# # insecure_skip_verify = true
+#
+# ## Consul checks' tag splitting
+# # When tags are formatted like "key:value" with ":" as a delimiter then
+# # they will be splitted and reported as proper key:value in Telegraf
+# # tag_delimiter = ":"
# # Read metrics from one or many couchbase clusters
@@ -1791,19 +1860,19 @@
# ## List of metrics collected on above servers
# ## Each metric consists in a name, a jmx path and either
# ## a pass or drop slice attribute.
-# ## This collect all heap memory usage metrics.
+# ##Â This collect all heap memory usage metrics.
# [[inputs.jolokia.metrics]]
# name = "heap_memory_usage"
# mbean = "java.lang:type=Memory"
# attribute = "HeapMemoryUsage"
#
-# ## This collect thread counts metrics.
+# ##Â This collect thread counts metrics.
# [[inputs.jolokia.metrics]]
# name = "thread_count"
# mbean = "java.lang:type=Threading"
# attribute = "TotalStartedThreadCount,ThreadCount,DaemonThreadCount,PeakThreadCount"
#
-# ## This collect number of class loaded/unloaded counts metrics.
+# ##Â This collect number of class loaded/unloaded counts metrics.
# [[inputs.jolokia.metrics]]
# name = "class_count"
# mbean = "java.lang:type=ClassLoading"
@@ -2259,7 +2328,7 @@
# reverse_metric_names = true
-# # A plugin to collect stats from Opensmtpd - a validating, recursive, and caching DNS resolver
+# # A plugin to collect stats from Opensmtpd - a validating, recursive, and caching DNS resolver
# [[inputs.opensmtpd]]
# ## If running as a restricted user you can prepend sudo for additional access:
# #use_sudo = false
@@ -3561,3 +3630,4 @@
# [[inputs.zipkin]]
# # path = "/api/v1/spans" # URL path for span data
# # port = 9411 # Port on which Telegraf listens
+
diff --git a/plugins/outputs/mqtt/README.md b/plugins/outputs/mqtt/README.md
index 716806783047ac3ed59ed55e36baafd9d0582719..14c166f9eb8763630c3f48a3b8391a2c7d75570f 100644
--- a/plugins/outputs/mqtt/README.md
+++ b/plugins/outputs/mqtt/README.md
@@ -11,6 +11,9 @@ This plugin writes to a [MQTT Broker](http://http://mqtt.org/) acting as a mqtt
topic_prefix = "telegraf"
## QoS policy for messages
+ ## 0 = at most once
+ ## 1 = at least once
+ ## 2 = exactly once
qos = 2
## username and password to connect MQTT server.
@@ -30,17 +33,12 @@ This plugin writes to a [MQTT Broker](http://http://mqtt.org/) acting as a mqtt
## Use TLS but skip chain & host verification
# insecure_skip_verify = false
- ## Batch messages in a topic
- ## batch = false
- ## Flag to determine if messages sent in a topic in a flush interval,
- ## need to be batched into one message.
- ## batch = true, batches the messages in a topic to one messages
- ## batch = false, default behaviour
+ ## When true, metrics will be sent in one MQTT message per flush. Otherwise,
+ ## metrics are written one metric per MQTT message.
# batch = false
-
## Data format to output.
- data_format = "influx"
+ # data_format = "influx"
```
### Required parameters:
diff --git a/plugins/outputs/mqtt/mqtt.go b/plugins/outputs/mqtt/mqtt.go
index 5228a083a1f1045c59bc2400edc34cba337a4350..6231045b8a4e8cee618ba0a905c670fafd8a812b 100644
--- a/plugins/outputs/mqtt/mqtt.go
+++ b/plugins/outputs/mqtt/mqtt.go
@@ -23,16 +23,22 @@ var sampleConfig = `
## ex: prefix/web01.example.com/mem
topic_prefix = "telegraf"
+ ## QoS policy for messages
+ ## 0 = at most once
+ ## 1 = at least once
+ ## 2 = exactly once
+ # qos = 2
+
## username and password to connect MQTT server.
# username = "telegraf"
# password = "metricsmetricsmetricsmetrics"
- ## Timeout for write operations. default: 5s
- # timeout = "5s"
-
## client ID, if not set a random ID is generated
# client_id = ""
+ ## Timeout for write operations. default: 5s
+ # timeout = "5s"
+
## Optional TLS Config
# tls_ca = "/etc/telegraf/ca.pem"
# tls_cert = "/etc/telegraf/cert.pem"
@@ -40,20 +46,15 @@ var sampleConfig = `
## Use TLS but skip chain & host verification
# insecure_skip_verify = false
+ ## When true, metrics will be sent in one MQTT message per flush. Otherwise,
+ ## metrics are written one metric per MQTT message.
+ # batch = false
+
## Data format to output.
## Each data format has its own unique set of configuration options, read
## more about them here:
## https://github.com/influxdata/telegraf/blob/master/docs/DATA_FORMATS_OUTPUT.md
data_format = "influx"
-
- ## Batch messages in a topic
- ## batch = false
- ## Flag to determine if messages sent in a topic in a flush interval,
- ## need to be batched into one message.
- ## batch = true, batches the messages in a topic to one messages
- ## batch = false, default behaviour
- # batch = false
-
`
type MQTT struct {