Refactor logsapi package (#129)

* Refactor logsapi

* Add test for subscribing to logs API

* Further abstract sending logs api subscription request

* Make sure to close logsapi server at test end and unset env vars

* Test with different port

* Improve and consolidate tests

* Allow logsapi listenerhost to be set for testing

* Minor improvements

* Respond with status code 500 if json cannot be unmarshalled

* No reason to close the body, the server does

* Fix variable names and other updates from code review

* Don't use a variable for the error in the method signature

* Add code review suggestion that was overwritten by a push with --force

* Don't initialize logsAPIListener in function, it's already defined

* No need to send request in go routine if a buffered channel is used

* Cancel the background context when a shutdown event is received

* Define UnmarshalJSON function for a LogEvent

* Handle case when json doesn't unmarshal correctly

* Use anon struct in UnmarshalJSON function

* Simplify UnmarshalJSON function

* Check first byte of record to determine if it's an object or string

* Use json.Decoder in test

Author: estolfo

apm-lambda-extension/logsapi/client.go

@@ -22,7 +22,6 @@ import (
 	"encoding/json"
 	"fmt"
 	"io/ioutil"
-	"log"
 	"net/http"
 
 	"github.com/pkg/errors"
@@ -130,8 +129,18 @@ type SubscribeResponse struct {
 }
 
 // Subscribe calls the Logs API to subscribe for the log events.
-func (c *Client) Subscribe(types []EventType, bufferingCfg BufferingCfg, destination Destination, extensionId string) (*SubscribeResponse, error) {
-
+func (c *Client) Subscribe(types []EventType, destinationURI URI, extensionId string) (*SubscribeResponse, error) {
+	bufferingCfg := BufferingCfg{
+		MaxItems:  10000,
+		MaxBytes:  262144,
+		TimeoutMS: 25,
+	}
+	destination := Destination{
+		Protocol:   HttpProto,
+		URI:        destinationURI,
+		HttpMethod: HttpPost,
+		Encoding:   JSON,
+	}
 	data, err := json.Marshal(
 		&SubscribeRequest{
 			SchemaVersion: SchemaVersionLatest,
@@ -153,7 +162,6 @@ func (c *Client) Subscribe(types []EventType, bufferingCfg BufferingCfg, destina
 	defer resp.Body.Close()
 
 	if resp.StatusCode == http.StatusAccepted {
-		log.Println("Logs API is not supported. Is this extension running in a local sandbox?")
 		return nil, errors.Errorf("Logs API is not supported in this environment")
 	} else if resp.StatusCode != http.StatusOK {
 		body, err := ioutil.ReadAll(resp.Body)