Feature/1363: Additional configuration for JSON parser

docs/DATA_FORMATS_INPUT.md

@@ -104,9 +104,23 @@ but can be overridden using the `name_override` config option.
 
 #### JSON Configuration:
 
-The JSON data format supports specifying "tag keys". If specified, keys
-will be searched for in the root-level of the JSON blob. If the key(s) exist,
-they will be applied as tags to the Telegraf metrics.
+The JSON data format supports specifying "tag_keys", "string_keys", and "json_query". 
+If specified, keys in "tag_keys" and "string_keys" will be searched for in the root-level 
+and any nested lists of the JSON blob. All int and float values are added to fields by default. 
+If the key(s) exist, they will be applied as tags or fields to the Telegraf metrics.  
+If "string_keys" is specified, the string will be added as a field.
+
+The "json_query" configuration is a gjson path to an JSON object or list of JSON objects.  
+If this path leads to an array of values or single data point an error will be thrown.  If this 
+configuration is specified, only the result of the query will be parsed and returned as metrics.  
+
+Object paths are specified using gjson path format, which is denoted by object keys 
+concatenated with "." to go deeper in nested JSON objects.  
+Additional information on gjson paths can be found here: https://github.com/tidwall/gjson#path-syntax
+
+The JSON data format also supports extracting time values through the config "json_time_key" and "json_time_format". 
+If "json_time_key" is set, "json_time_format" must be specified.  The "json_time_key" describes the name of the field containing time information.  The "json_time_format" must be a recognized Go time format.  
+More info on time formats can be found here: https://golang.org/src/time/format.go
 
 For example, if you had this configuration:
 
@@ -124,11 +138,25 @@ For example, if you had this configuration:
   ## https://github.com/influxdata/telegraf/blob/master/docs/DATA_FORMATS_INPUT.md
   data_format = "json"
 
-  ## List of tag names to extract from top-level of JSON server response
+  ## List of tag names to extract from JSON server response
   tag_keys = [
     "my_tag_1",
     "my_tag_2"
   ]
+
+  ## List of field names to extract from JSON and add as string fields
+  # string_fields = []
+
+  ## gjson query path to specify a specific chunk of JSON to be parsed with the above configuration
+  ## if not specified, the whole file will be parsed. 
+  ## gjson query paths are described here: 
+  # json_query = ""
+
+  ## holds the name of the tag of timestamp
+  # json_time_key = ""
+
+  ## holds the format of timestamp to be parsed
+  # json_time_format = ""
 ```
 
 with this JSON output from a command:
@@ -173,6 +201,19 @@ For example, if the following configuration:
     "my_tag_1",
     "my_tag_2"
   ]
+
+  ## List of field names to extract from JSON and add as string fields
+  # string_fields = []
+
+  ## gjson query path to specify a specific chunk of JSON to be parsed with the above configuration
+  ## if not specified, the whole file will be parsed
+  # json_query = ""
+
+  ## holds the name of the tag of timestamp
+  # json_time_key = "b_time"
+
+  ## holds the format of timestamp to be parsed
+  # json_time_format = "02 Jan 06 15:04 MST"
 ```
 
 with this JSON output from a command:
@@ -182,27 +223,89 @@ with this JSON output from a command:
     {
         "a": 5,
         "b": {
-            "c": 6
+            "c": 6,
+            "time":"04 Jan 06 15:04 MST"
         },
         "my_tag_1": "foo",
         "my_tag_2": "baz"
     },
     {
         "a": 7,
         "b": {
-            "c": 8
+            "c": 8,
+            "time":"11 Jan 07 15:04 MST"
         },
         "my_tag_1": "bar",
         "my_tag_2": "baz"
     }
 ]
 ```
 
-Your Telegraf metrics would get tagged with "my_tag_1" and "my_tag_2"
+Your Telegraf metrics would get tagged with "my_tag_1" and "my_tag_2" and fielded with "b_c"
+The metric's time will be a time.Time object, as specified by "b_time"
+
+```
+exec_mycollector,my_tag_1=foo,my_tag_2=baz b_c=6 1136387040000000000
+exec_mycollector,my_tag_1=bar,my_tag_2=baz b_c=8 1168527840000000000
+```
+
+If you want to only use a specific portion of your JSON, use the "json_query" 
+configuration to specify a path to a JSON object.
+
+For example, with the following config:
+```toml
+[[inputs.exec]]
+  ## Commands array
+  commands = ["/usr/bin/mycollector --foo=bar"]
+
+  ## measurement name suffix (for separating different commands)
+  name_suffix = "_mycollector"
+
+  ## Data format to consume.
+  ## 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_INPUT.md
+  data_format = "json"
+
+  ## List of tag names to extract from top-level of JSON server response
+  tag_keys = ["first"]
+
+  ## List of field names to extract from JSON and add as string fields
+  string_fields = ["last"]
+
+  ## gjson query path to specify a specific chunk of JSON to be parsed with the above configuration
+  ## if not specified, the whole file will be parsed
+  json_query = "obj.friends"
+
+  ## holds the name of the tag of timestamp
+  # json_time_key = ""
+
+  ## holds the format of timestamp to be parsed
+  # json_time_format = ""
+```
+
+with this JSON as input:
+```json
+{
+    "obj": {
+        "name": {"first": "Tom", "last": "Anderson"},
+        "age":37,
+        "children": ["Sara","Alex","Jack"],
+        "fav.movie": "Deer Hunter",
+        "friends": [
+            {"first": "Dale", "last": "Murphy", "age": 44},
+            {"first": "Roger", "last": "Craig", "age": 68},
+            {"first": "Jane", "last": "Murphy", "age": 47}
+        ]
+    }
+}
+```
+You would recieve 3 metrics tagged with "first", and fielded with "last" and "age"
 
 ```
-exec_mycollector,my_tag_1=foo,my_tag_2=baz a=5,b_c=6
-exec_mycollector,my_tag_1=bar,my_tag_2=baz a=7,b_c=8
+exec_mycollector, "first":"Dale" "last":"Murphy","age":44
+exec_mycollector, "first":"Roger" "last":"Craig","age":68
+exec_mycollector, "first":"Jane" "last":"Murphy","age":47
 ```
 
 # Value:

internal/config/config.go

@@ -1261,6 +1261,42 @@ func buildParser(name string, tbl *ast.Table) (parsers.Parser, error) {
 		}
 	}
 
+	if node, ok := tbl.Fields["string_fields"]; 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 {
+						c.StringFields = append(c.StringFields, str.Value)
+					}
+				}
+			}
+		}
+	}
+
+	if node, ok := tbl.Fields["json_query"]; ok {
+		if kv, ok := node.(*ast.KeyValue); ok {
+			if str, ok := kv.Value.(*ast.String); ok {
+				c.JSONQuery = str.Value
+			}
+		}
+	}
+
+	if node, ok := tbl.Fields["json_time_key"]; ok {
+		if kv, ok := node.(*ast.KeyValue); ok {
+			if str, ok := kv.Value.(*ast.String); ok {
+				c.JSONTimeKey = str.Value
+			}
+		}
+	}
+
+	if node, ok := tbl.Fields["json_time_format"]; ok {
+		if kv, ok := node.(*ast.KeyValue); ok {
+			if str, ok := kv.Value.(*ast.String); ok {
+				c.JSONTimeFormat = str.Value
+			}
+		}
+	}
+
 	if node, ok := tbl.Fields["data_type"]; ok {
 		if kv, ok := node.(*ast.KeyValue); ok {
 			if str, ok := kv.Value.(*ast.String); ok {
@@ -1344,6 +1380,10 @@ func buildParser(name string, tbl *ast.Table) (parsers.Parser, error) {
 	delete(tbl.Fields, "separator")
 	delete(tbl.Fields, "templates")
 	delete(tbl.Fields, "tag_keys")
+	delete(tbl.Fields, "string_fields")
+	delete(tbl.Fields, "json_query")
+	delete(tbl.Fields, "json_time_key")
+	delete(tbl.Fields, "json_time_format")
 	delete(tbl.Fields, "data_type")
 	delete(tbl.Fields, "collectd_auth_file")
 	delete(tbl.Fields, "collectd_security_level")

internal/config/config_test.go

@@ -143,7 +143,10 @@ func TestConfig_LoadDirectory(t *testing.T) {
 		"Testdata did not produce correct memcached metadata.")
 
 	ex := inputs.Inputs["exec"]().(*exec.Exec)
-	p, err := parsers.NewJSONParser("exec", nil, nil)
+	p, err := parsers.NewParser(&parsers.Config{
+		MetricName: "exec",
+		DataFormat: "json",
+	})
 	assert.NoError(t, err)
 	ex.SetParser(p)
 	ex.Command = "/usr/bin/myothercollector --foo=bar"

plugins/inputs/exec/exec_test.go

@@ -93,7 +93,10 @@ func (r runnerMock) Run(e *Exec, command string, acc telegraf.Accumulator) ([]by
 }
 
 func TestExec(t *testing.T) {
-	parser, _ := parsers.NewJSONParser("exec", []string{}, nil)
+	parser, _ := parsers.NewParser(&parsers.Config{
+		DataFormat: "json",
+		MetricName: "exec",
+	})
 	e := &Exec{
 		runner:   newRunnerMock([]byte(validJson), nil),
 		Commands: []string{"testcommand arg1"},
@@ -119,7 +122,10 @@ func TestExec(t *testing.T) {
 }
 
 func TestExecMalformed(t *testing.T) {
-	parser, _ := parsers.NewJSONParser("exec", []string{}, nil)
+	parser, _ := parsers.NewParser(&parsers.Config{
+		DataFormat: "json",
+		MetricName: "exec",
+	})
 	e := &Exec{
 		runner:   newRunnerMock([]byte(malformedJson), nil),
 		Commands: []string{"badcommand arg1"},
@@ -132,7 +138,10 @@ func TestExecMalformed(t *testing.T) {
 }
 
 func TestCommandError(t *testing.T) {
-	parser, _ := parsers.NewJSONParser("exec", []string{}, nil)
+	parser, _ := parsers.NewParser(&parsers.Config{
+		DataFormat: "json",
+		MetricName: "exec",
+	})
 	e := &Exec{
 		runner:   newRunnerMock(nil, fmt.Errorf("exit status code 1")),
 		Commands: []string{"badcommand"},

plugins/inputs/http/http_test.go

@@ -26,7 +26,11 @@ func TestHTTPwithJSONFormat(t *testing.T) {
 		URLs: []string{url},
 	}
 	metricName := "metricName"
-	p, _ := parsers.NewJSONParser(metricName, nil, nil)
+
+	p, _ := parsers.NewParser(&parsers.Config{
+		DataFormat: "json",
+		MetricName: "metricName",
+	})
 	plugin.SetParser(p)
 
 	var acc testutil.Accumulator
@@ -63,8 +67,11 @@ func TestHTTPHeaders(t *testing.T) {
 		URLs:    []string{url},
 		Headers: map[string]string{header: headerValue},
 	}
-	metricName := "metricName"
-	p, _ := parsers.NewJSONParser(metricName, nil, nil)
+
+	p, _ := parsers.NewParser(&parsers.Config{
+		DataFormat: "json",
+		MetricName: "metricName",
+	})
 	plugin.SetParser(p)
 
 	var acc testutil.Accumulator
@@ -83,7 +90,10 @@ func TestInvalidStatusCode(t *testing.T) {
 	}
 
 	metricName := "metricName"
-	p, _ := parsers.NewJSONParser(metricName, nil, nil)
+	p, _ := parsers.NewParser(&parsers.Config{
+		DataFormat: "json",
+		MetricName: metricName,
+	})
 	plugin.SetParser(p)
 
 	var acc testutil.Accumulator
@@ -105,8 +115,10 @@ func TestMethod(t *testing.T) {
 		Method: "POST",
 	}
 
-	metricName := "metricName"
-	p, _ := parsers.NewJSONParser(metricName, nil, nil)
+	p, _ := parsers.NewParser(&parsers.Config{
+		DataFormat: "json",
+		MetricName: "metricName",
+	})
 	plugin.SetParser(p)
 
 	var acc testutil.Accumulator

plugins/inputs/httpjson/httpjson.go

@@ -181,7 +181,12 @@ func (h *HttpJson) gatherServer(
 		"server": serverURL,
 	}
 
-	parser, err := parsers.NewJSONParser(msrmnt_name, h.TagKeys, tags)
+	parser, err := parsers.NewParser(&parsers.Config{
+		DataFormat:  "json",
+		MetricName:  msrmnt_name,
+		TagKeys:     h.TagKeys,
+		DefaultTags: tags,
+	})
 	if err != nil {
 		return err
 	}

plugins/inputs/kafka_consumer/kafka_consumer_test.go

@@ -125,7 +125,10 @@ func TestRunParserAndGatherJSON(t *testing.T) {
 	k.acc = &acc
 	defer close(k.done)
 
-	k.parser, _ = parsers.NewJSONParser("kafka_json_test", []string{}, nil)
+	k.parser, _ = parsers.NewParser(&parsers.Config{
+		DataFormat: "json",
+		MetricName: "kafka_json_test",
+	})
 	go k.receiver()
 	in <- saramaMsg(testMsgJSON)
 	acc.Wait(1)

plugins/inputs/kafka_consumer_legacy/kafka_consumer_legacy_test.go

@@ -125,7 +125,10 @@ func TestRunParserAndGatherJSON(t *testing.T) {
 	k.acc = &acc
 	defer close(k.done)
 
-	k.parser, _ = parsers.NewJSONParser("kafka_json_test", []string{}, nil)
+	k.parser, _ = parsers.NewParser(&parsers.Config{
+		DataFormat: "json",
+		MetricName: "kafka_json_test",
+	})
 	go k.receiver()
 	in <- saramaMsg(testMsgJSON)
 	acc.Wait(1)

plugins/inputs/mqtt_consumer/mqtt_consumer_test.go

@@ -172,7 +172,10 @@ func TestRunParserAndGatherJSON(t *testing.T) {
 	n.acc = &acc
 	defer close(n.done)
 
-	n.parser, _ = parsers.NewJSONParser("nats_json_test", []string{}, nil)
+	n.parser, _ = parsers.NewParser(&parsers.Config{
+		DataFormat: "json",
+		MetricName: "nats_json_test",
+	})
 	go n.receiver()
 	in <- mqttMsg(testMsgJSON)
 

plugins/inputs/nats_consumer/nats_consumer_test.go

@@ -108,7 +108,10 @@ func TestRunParserAndGatherJSON(t *testing.T) {
 	n.acc = &acc
 	defer close(n.done)
 
-	n.parser, _ = parsers.NewJSONParser("nats_json_test", []string{}, nil)
+	n.parser, _ = parsers.NewParser(&parsers.Config{
+		DataFormat: "json",
+		MetricName: "nats_json_test",
+	})
 	n.wg.Add(1)
 	go n.receiver()
 	in <- natsMsg(testMsgJSON)

plugins/inputs/tcp_listener/tcp_listener_test.go

@@ -300,7 +300,10 @@ func TestRunParserJSONMsg(t *testing.T) {
 	listener.acc = &acc
 	defer close(listener.done)
 
-	listener.parser, _ = parsers.NewJSONParser("udp_json_test", []string{}, nil)
+	listener.parser, _ = parsers.NewParser(&parsers.Config{
+		DataFormat: "json",
+		MetricName: "udp_json_test",
+	})
 	listener.wg.Add(1)
 	go listener.tcpParser()