Adds support for removing/keeping tags from metrics

closes #706

CHANGELOG.md

@@ -1,5 +1,20 @@
 ## v0.13 [unreleased]
 
+### Release Notes
+- `tagexclude` and `tagexclude` are now available, which can be used to remove
+tags from measurements on inputs and outputs. See 
+[the configuration doc](https://github.com/influxdata/telegraf/blob/master/docs/CONFIGURATION.md)
+for more details.
+- **Measurement filtering:** All measurement filters now match based on glob
+only. Previously there was an undocumented behavior where filters would match
+based on _prefix_ in addition to globs. This means that a filter like
+`fielddrop = ["time_"]` will need to be changed to `fielddrop = ["time_*"]`
+
+### Features
+- [#1017](https://github.com/influxdata/telegraf/pull/1017): taginclude and tagexclude arguments.
+
+### Bugfixes
+
 ## v0.12.1 [2016-04-14]
 
 ### Release Notes

Godeps

@@ -16,6 +16,7 @@ github.com/eapache/go-resiliency b86b1ec0dd4209a588dc1285cdd471e73525c0b3
 github.com/eapache/queue ded5959c0d4e360646dc9e9908cff48666781367
 github.com/eclipse/paho.mqtt.golang 0f7a459f04f13a41b7ed752d47944528d4bf9a86
 github.com/go-sql-driver/mysql 1fca743146605a172a266e1654e01e5cd5669bee
+github.com/gobwas/glob d877f6352135181470c40c73ebb81aefa22115fa
 github.com/golang/protobuf 552c7b9542c194800fd493123b3798ef0a832032
 github.com/golang/snappy 427fb6fc07997f43afa32f35e850833760e489a7
 github.com/gonuts/go-shellquote e842a11b24c6abfb3dd27af69a17f482e4b483c2

agent/accumulator.go

@@ -96,6 +96,7 @@ func (ac *accumulator) AddFields(
 			tags[k] = v
 		}
 	}
+	ac.inputConfig.Filter.FilterTags(tags)
 
 	result := make(map[string]interface{})
 	for k, v := range fields {

agent/accumulator_test.go

@@ -300,3 +300,35 @@ func TestAddBools(t *testing.T) {
 		fmt.Sprintf("acctest,acc=test,default=tag value=false %d", now.UnixNano()),
 		actual)
 }
+
+// Test that tag filters get applied to metrics.
+func TestAccFilterTags(t *testing.T) {
+	a := accumulator{}
+	now := time.Now()
+	a.metrics = make(chan telegraf.Metric, 10)
+	defer close(a.metrics)
+	filter := internal_models.Filter{
+		TagExclude: []string{"acc"},
+	}
+	assert.NoError(t, filter.CompileFilter())
+	a.inputConfig = &internal_models.InputConfig{}
+	a.inputConfig.Filter = filter
+
+	a.Add("acctest", float64(101), map[string]string{})
+	a.Add("acctest", float64(101), map[string]string{"acc": "test"})
+	a.Add("acctest", float64(101), map[string]string{"acc": "test"}, now)
+
+	testm := <-a.metrics
+	actual := testm.String()
+	assert.Contains(t, actual, "acctest value=101")
+
+	testm = <-a.metrics
+	actual = testm.String()
+	assert.Contains(t, actual, "acctest value=101")
+
+	testm = <-a.metrics
+	actual = testm.String()
+	assert.Equal(t,
+		fmt.Sprintf("acctest value=101 %d", now.UnixNano()),
+		actual)
+}

docs/CONFIGURATION.md

@@ -3,11 +3,20 @@
 ## Generating a Configuration File
 
 A default Telegraf config file can be generated using the -sample-config flag:
-`telegraf -sample-config > telegraf.conf`
+
+```
+telegraf -sample-config > telegraf.conf
+```
 
 To generate a file with specific inputs and outputs, you can use the
 -input-filter and -output-filter flags:
-`telegraf -sample-config -input-filter cpu:mem:net:swap -output-filter influxdb:kafka`
+
+```
+telegraf -sample-config -input-filter cpu:mem:net:swap -output-filter influxdb:kafka
+```
+
+You can see the latest config file with all available plugins
+[here](https://github.com/influxdata/telegraf/blob/master/etc/telegraf.conf)
 
 ## Environment Variables
 
@@ -17,8 +26,8 @@ for numbers and booleans they should be plain (ie, $INT_VAR, $BOOL_VAR)
 
 ## `[global_tags]` Configuration
 
-Global tags can be specific in the `[global_tags]` section of the config file in
-key="value" format. All metrics being gathered on this host will be tagged
+Global tags can be specified in the `[global_tags]` section of the config file
+in key="value" format. All metrics being gathered on this host will be tagged
 with the tags specified here.
 
 ## `[agent]` Configuration
@@ -47,36 +56,42 @@ ie, a jitter of 5s and flush_interval 10s means flushes will happen every 10-15s
 * **quiet**: Run telegraf in quiet mode.
 * **hostname**: Override default hostname, if empty use os.Hostname().
 
-## `[inputs.xxx]` Configuration
-
-There are some configuration options that are configurable per input:
-
-* **name_override**: Override the base name of the measurement.
-(Default is the name of the input).
-* **name_prefix**: Specifies a prefix to attach to the measurement name.
-* **name_suffix**: Specifies a suffix to attach to the measurement name.
-* **tags**: A map of tags to apply to a specific input's measurements.
-* **interval**: How often to gather this metric. Normal plugins use a single
-global interval, but if one particular input should be run less or more often,
-you can configure that here.
-
-#### Input Filters
+#### Measurement Filtering
 
-There are also filters that can be configured per input:
+Filters can be configured per input or output, see below for examples.
 
 * **namepass**: An array of strings that is used to filter metrics generated by the
 current input. Each string in the array is tested as a glob match against
 measurement names and if it matches, the field is emitted.
 * **namedrop**: The inverse of pass, if a measurement name matches, it is not emitted.
 * **fieldpass**: An array of strings that is used to filter metrics generated by the
 current input. Each string in the array is tested as a glob match against field names
-and if it matches, the field is emitted.
+and if it matches, the field is emitted. fieldpass is not available for outputs.
 * **fielddrop**: The inverse of pass, if a field name matches, it is not emitted.
+fielddrop is not available for outputs.
 * **tagpass**: tag names and arrays of strings that are used to filter
 measurements by the current input. Each string in the array is tested as a glob
 match against the tag name, and if it matches the measurement is emitted.
 * **tagdrop**: The inverse of tagpass. If a tag matches, the measurement is not
 emitted. This is tested on measurements that have passed the tagpass test.
+* **tagexclude**: tagexclude can be used to exclude a tag from measurement(s).
+As opposed to tagdrop, which will drop an entire measurement based on it's 
+tags, tagexclude simply strips the given tag keys from the measurement.
+* **taginclude**: taginclude is the inverse of tagexclude. It will only include
+the tag keys in the final measurement.
+
+## Input Configuration
+
+Some configuration options are configurable per input:
+
+* **name_override**: Override the base name of the measurement.
+(Default is the name of the input).
+* **name_prefix**: Specifies a prefix to attach to the measurement name.
+* **name_suffix**: Specifies a suffix to attach to the measurement name.
+* **tags**: A map of tags to apply to a specific input's measurements.
+* **interval**: How often to gather this metric. Normal plugins use a single
+global interval, but if one particular input should be run less or more often,
+you can configure that here.
 
 #### Input Configuration Examples
 
@@ -155,6 +170,20 @@ fields which begin with `time_`.
   namepass = ["rest_client_*"]
 ```
 
+#### Input Config: taginclude and tagexclude
+
+```toml
+# Only include the "cpu" tag in the measurements for the cpu plugin.
+[[inputs.cpu]]
+  percpu = true
+  totalcpu = true
+  taginclude = ["cpu"]
+
+# Exclude the "fstype" tag from the measurements for the disk plugin.
+[[inputs.disk]]
+  tagexclude = ["fstype"]
+```
+
 #### Input config: prefix, suffix, and override
 
 This plugin will emit measurements with the name `cpu_total`
@@ -180,6 +209,9 @@ This will emit measurements with the name `foobar`
 This plugin will emit measurements with two additional tags: `tag1=foo` and
 `tag2=bar`
 
+NOTE: Order matters, the `[inputs.cpu.tags]` table must be at the _end_ of the
+plugin definition.
+
 ```toml
 [[inputs.cpu]]
   percpu = false
@@ -208,15 +240,12 @@ to avoid measurement collisions:
   fielddrop = ["cpu_time*"]
 ```
 
-## `[outputs.xxx]` Configuration
+## Output Configuration
 
 Telegraf also supports specifying multiple output sinks to send data to,
 configuring each output sink is different, but examples can be
 found by running `telegraf -sample-config`.
 
-Outputs also support the same configurable options as inputs
-(namepass, namedrop, tagpass, tagdrop)
-
 ```toml
 [[outputs.influxdb]]
   urls = [ "http://localhost:8086" ]

docs/LICENSE_OF_DEPENDENCIES.md

@@ -28,6 +28,5 @@
 - github.com/wvanbergen/kazoo-go [MIT LICENSE](https://github.com/wvanbergen/kazoo-go/blob/master/MIT-LICENSE)
 - gopkg.in/dancannon/gorethink.v1 [APACHE LICENSE](https://github.com/dancannon/gorethink/blob/v1.1.2/LICENSE)
 - gopkg.in/mgo.v2 [BSD LICENSE](https://github.com/go-mgo/mgo/blob/v2/LICENSE)
-- golang.org/x/crypto/* [BSD LICENSE](https://github.com/golang/crypto/blob/master/LICENSE)
-- internal Glob function [MIT LICENSE](https://github.com/ryanuber/go-glob/blob/master/LICENSE)
+- golang.org/x/crypto/ [BSD LICENSE](https://github.com/golang/crypto/blob/master/LICENSE)
 

internal/config/config.go

@@ -580,9 +580,9 @@ func (c *Config) addInput(name string, table *ast.Table) error {
 
 // buildFilter builds a Filter
 // (tagpass/tagdrop/namepass/namedrop/fieldpass/fielddrop) to
-// be inserted into the internal_models.OutputConfig/internal_models.InputConfig to be used for prefix
-// filtering on tags and measurements
-func buildFilter(tbl *ast.Table) internal_models.Filter {
+// be inserted into the internal_models.OutputConfig/internal_models.InputConfig
+// to be used for glob filtering on tags and measurements
+func buildFilter(tbl *ast.Table) (internal_models.Filter, error) {
 	f := internal_models.Filter{}
 
 	if node, ok := tbl.Fields["namepass"]; ok {
@@ -681,6 +681,33 @@ func buildFilter(tbl *ast.Table) internal_models.Filter {
 		}
 	}
 
+	if node, ok := tbl.Fields["tagexclude"]; ok {
+		if kv, ok := node.(*ast.KeyValue); ok {
+			if ary, ok := kv.Value.(*ast.Array); ok {
+				for _, elem := range ary.Value {
+					if str, ok := elem.(*ast.String); ok {
+						f.TagExclude = append(f.TagExclude, str.Value)
+					}
+				}
+			}
+		}
+	}
+
+	if node, ok := tbl.Fields["taginclude"]; ok {
+		if kv, ok := node.(*ast.KeyValue); ok {
+			if ary, ok := kv.Value.(*ast.Array); ok {
+				for _, elem := range ary.Value {
+					if str, ok := elem.(*ast.String); ok {
+						f.TagInclude = append(f.TagInclude, str.Value)
+					}
+				}
+			}
+		}
+	}
+	if err := f.CompileFilter(); err != nil {
+		return f, err
+	}
+
 	delete(tbl.Fields, "namedrop")
 	delete(tbl.Fields, "namepass")
 	delete(tbl.Fields, "fielddrop")
@@ -689,7 +716,9 @@ func buildFilter(tbl *ast.Table) internal_models.Filter {
 	delete(tbl.Fields, "pass")
 	delete(tbl.Fields, "tagdrop")
 	delete(tbl.Fields, "tagpass")
-	return f
+	delete(tbl.Fields, "tagexclude")
+	delete(tbl.Fields, "taginclude")
+	return f, nil
 }
 
 // buildInput parses input specific items from the ast.Table,
@@ -748,7 +777,11 @@ func buildInput(name string, tbl *ast.Table) (*internal_models.InputConfig, erro
 	delete(tbl.Fields, "name_override")
 	delete(tbl.Fields, "interval")
 	delete(tbl.Fields, "tags")
-	cp.Filter = buildFilter(tbl)
+	var err error
+	cp.Filter, err = buildFilter(tbl)
+	if err != nil {
+		return cp, err
+	}
 	return cp, nil
 }
 
@@ -864,13 +897,18 @@ func buildSerializer(name string, tbl *ast.Table) (serializers.Serializer, error
 	return serializers.NewSerializer(c)
 }
 
-// buildOutput parses output specific items from the ast.Table, builds the filter and returns an
+// buildOutput parses output specific items from the ast.Table,
+// builds the filter and returns an
 // internal_models.OutputConfig to be inserted into internal_models.RunningInput
 // Note: error exists in the return for future calls that might require error
 func buildOutput(name string, tbl *ast.Table) (*internal_models.OutputConfig, error) {
+	filter, err := buildFilter(tbl)
+	if err != nil {
+		return nil, err
+	}
 	oc := &internal_models.OutputConfig{
 		Name:   name,
-		Filter: buildFilter(tbl),
+		Filter: filter,
 	}
 	// Outputs don't support FieldDrop/FieldPass, so set to NameDrop/NamePass
 	if len(oc.Filter.FieldDrop) > 0 {