EU Datacenter Support

Adds support for `WithRegion` and the new `RegionEU` flag

CHANGELOG.md

@@ -1,5 +1,13 @@
 # Changelog
 
+## March 24, 2021
+### Added
+- Support for EU region
+- Allow using custom `*http.Client`
+### Removed
+### Changed
+- `customerio.NewAPIClient` and `customerio.NewTrackClient`  have a new variadic parameter for options in order to choose US/EU region and/or customer HTTP client.
+
 ## December 3, 2020
 ### Added
 - Support for transactional api

README.md

@@ -49,13 +49,14 @@ You'll be able to integrate **fully** with [Customer.io](http://customer.io) wit
 
 ### Setup
 
-Create an instance of the client with your [customer.io](http://customer.io) credentials
-which can be found on the [customer.io integration screen](https://manage.customer.io/integration).
+Create an instance of the client with your [Customer.io credentials](https://fly.customer.io/settings/api_credentials).
 
 ```go
-track := customerio.NewTrackClient("YOUR SITE ID", "YOUR API SECRET KEY")
+track := customerio.NewTrackClient("YOUR SITE ID", "YOUR API SECRET KEY", customerio.WithRegion(customerio.RegionUS))
 ```
 
+Your account region—`RegionUS` or `RegionEU`—is optional. If you do not specify your region, we assume that your account is based in the US (`RegionUS`). If your account is based in the EU and you do not provide the correct region, we'll route requests from the US to `RegionEU` accordingly, however this may cause data to be logged in the US. 
+
 ### Identify logged in customers
 
 Tracking data of logged in customers is a key part of [Customer.io](http://customer.io). In order to
@@ -194,7 +195,7 @@ You can also send attachments with your message. Use `Attach` to encode attachme
 ```go
 import "github.com/customerio/go-customerio"
 
-client := customerio.NewAPIClient("<extapikey>");
+client := customerio.NewAPIClient("<extapikey>", customerio.WithRegion(customerio.RegionUS));
 
 // TransactionalMessageId — the ID of the transactional message you want to send.
 // To                     — the email address of your recipients.

api.go

@@ -16,12 +16,17 @@ type APIClient struct {
 
 // NewAPIClient prepares a client for use with the Customer.io API, see: https://customer.io/docs/api/#apicoreintroduction
 // using an App API Key from https://fly.customer.io/settings/api_credentials?keyType=app
-func NewAPIClient(key string) *APIClient {
-	return &APIClient{
+func NewAPIClient(key string, opts ...option) *APIClient {
+	client := &APIClient{
 		Key:    key,
 		Client: http.DefaultClient,
 		URL:    "https://api.customer.io",
 	}
+
+	for _, opt := range opts {
+		opt.api(client)
+	}
+	return client
 }
 
 func (c *APIClient) doRequest(ctx context.Context, verb, requestPath string, body interface{}) ([]byte, int, error) {
@@ -30,7 +35,7 @@ func (c *APIClient) doRequest(ctx context.Context, verb, requestPath string, bod
 		return nil, 0, err
 	}
 
-	req, err := http.NewRequest("POST", c.URL+requestPath, bytes.NewBuffer(b))
+	req, err := http.NewRequest(verb, c.URL+requestPath, bytes.NewBuffer(b))
 	if err != nil {
 		return nil, 0, err
 	}

customerio.go

@@ -39,24 +39,30 @@ func (e ParamError) Error() string { return e.Param + ": missing" }
 
 // NewTrackClient prepares a client for use with the Customer.io track API, see: https://customer.io/docs/api/#apitrackintroduction
 // using a Tracking Site ID and API Key pair from https://fly.customer.io/settings/api_credentials
-func NewTrackClient(siteID, apiKey string) *CustomerIO {
-	return NewCustomerIO(siteID, apiKey)
-}
-
-// NewCustomerIO prepares a client for use with the Customer.io track API, see: https://customer.io/docs/api/#apitrackintroduction
-// deprecated in favour of NewTrackClient
-func NewCustomerIO(siteID, apiKey string) *CustomerIO {
+func NewTrackClient(siteID, apiKey string, opts ...option) *CustomerIO {
 	client := &http.Client{
 		Transport: &http.Transport{
 			MaxIdleConnsPerHost: 100,
 		},
 	}
-	return &CustomerIO{
+	c := &CustomerIO{
 		siteID: siteID,
 		apiKey: apiKey,
 		URL:    "https://track.customer.io",
 		Client: client,
 	}
+
+	for _, opt := range opts {
+		opt.track(c)
+	}
+
+	return c
+}
+
+// NewCustomerIO prepares a client for use with the Customer.io track API, see: https://customer.io/docs/api/#apitrackintroduction
+// deprecated in favour of NewTrackClient
+func NewCustomerIO(siteID, apiKey string) *CustomerIO {
+	return NewTrackClient(siteID, apiKey)
 }
 
 // Identify identifies a customer and sets their attributes

examples/transactional.go

@@ -12,7 +12,7 @@ func main() {
 
 	ctx := context.Background()
 
-	client := customerio.NewAPIClient("<your-key-here>")
+	client := customerio.NewAPIClient("<your-key-here>", customerio.WithRegion(customerio.RegionUS))
 
 	req := customerio.SendEmailRequest{
 		Identifiers: map[string]string{

options.go

@@ -0,0 +1,46 @@
+package customerio
+
+import "net/http"
+
+type option struct {
+	api   func(*APIClient)
+	track func(*CustomerIO)
+}
+
+type region struct {
+	apiURL   string
+	trackURL string
+}
+
+var (
+	RegionUS = region{
+		apiURL:   "https://api.customer.io",
+		trackURL: "https://track.customer.io",
+	}
+	RegionEU = region{
+		apiURL:   "https://api-eu.customer.io",
+		trackURL: "https://track-eu.customer.io",
+	}
+)
+
+func WithRegion(r region) option {
+	return option{
+		api: func(a *APIClient) {
+			a.URL = r.apiURL
+		},
+		track: func(c *CustomerIO) {
+			c.URL = r.trackURL
+		},
+	}
+}
+
+func WithHTTPClient(client *http.Client) option {
+	return option{
+		api: func(a *APIClient) {
+			a.Client = client
+		},
+		track: func(c *CustomerIO) {
+			c.Client = client
+		},
+	}
+}

options_test.go

@@ -0,0 +1,45 @@
+package customerio
+
+import (
+	"net/http"
+	"reflect"
+	"testing"
+)
+
+func TestAPIOptions(t *testing.T) {
+
+	client := NewAPIClient("mykey")
+	if client.URL != RegionUS.apiURL {
+		t.Errorf("wrong default url. got: %s, want: %s", client.URL, RegionUS.apiURL)
+	}
+
+	client = NewAPIClient("mykey", WithRegion(RegionEU))
+	if client.URL != RegionEU.apiURL {
+		t.Errorf("wrong url. got: %s, want: %s", client.URL, RegionEU.apiURL)
+	}
+
+	hc := &http.Client{}
+	client = NewAPIClient("mykey", WithHTTPClient(hc))
+	if !reflect.DeepEqual(client.Client, hc) {
+		t.Errorf("wrong http client. got: %#v, want: %#v", client.Client, hc)
+	}
+}
+
+func TestTrackOptions(t *testing.T) {
+
+	client := NewTrackClient("site_id", "api_key")
+	if client.URL != RegionUS.trackURL {
+		t.Errorf("wrong default url. got: %s, want: %s", client.URL, RegionUS.trackURL)
+	}
+
+	client = NewTrackClient("site_id", "api_key", WithRegion(RegionEU))
+	if client.URL != RegionEU.trackURL {
+		t.Errorf("wrong url. got: %s, want: %s", client.URL, RegionEU.trackURL)
+	}
+
+	hc := &http.Client{}
+	client = NewTrackClient("site_id", "api_key", WithHTTPClient(hc))
+	if !reflect.DeepEqual(client.Client, hc) {
+		t.Errorf("wrong http client. got: %#v, want: %#v", client.Client, hc)
+	}
+}