feat: authenticate with access token

README.md

@@ -70,6 +70,20 @@ if err != nil {
 }
 ```
 
+Authenticate with an Access Token
+- Implement your own OAuth flow and use the resulting `access_token` in the response
+
+```go
+sf, sfErr := salesforce.Init(salesforce.Creds{
+    Domain:      DOMAIN,
+    AccessToken: ACCESS_TOKEN,
+})
+if err != nil {
+    panic(err)
+}
+```
+
+
 ## SOQL
 Query Salesforce records
 - [Review Salesforce REST API resources for queries](https://developer.salesforce.com/docs/atlas.en-us.api_rest.meta/api_rest/resources_query.htm)

auth.go

@@ -26,15 +26,35 @@ type Creds struct {
 	SecurityToken  string
 	ConsumerKey    string
 	ConsumerSecret string
+	AccessToken    string
 }
 
+const (
+	grantTypePassword          = "password"
+	grantTypeClientCredentials = "client_credentials"
+)
+
 func validateAuth(sf Salesforce) error {
 	if sf.auth == nil || sf.auth.AccessToken == "" {
 		return errors.New("not authenticated: please use salesforce.Init()")
 	}
 	return nil
 }
 
+func validateSession(auth authentication) error {
+	if err := validateAuth(Salesforce{auth: &auth}); err != nil {
+		return err
+	}
+	resp, err := doRequest(http.MethodGet, "/limits", jsonType, auth, "")
+	if err != nil {
+		return err
+	}
+	if resp.StatusCode != http.StatusOK {
+		return processSalesforceError(*resp)
+	}
+	return nil
+}
+
 func doAuth(url string, body *strings.Reader) (*authentication, error) {
 	resp, err := http.Post(url, "application/x-www-form-urlencoded", body)
 	if err != nil {
@@ -61,7 +81,7 @@ func doAuth(url string, body *strings.Reader) (*authentication, error) {
 
 func usernamePasswordFlow(domain string, username string, password string, securityToken string, consumerKey string, consumerSecret string) (*authentication, error) {
 	payload := url.Values{
-		"grant_type":    {"password"},
+		"grant_type":    {grantTypePassword},
 		"client_id":     {consumerKey},
 		"client_secret": {consumerSecret},
 		"username":      {username},
@@ -78,7 +98,7 @@ func usernamePasswordFlow(domain string, username string, password string, secur
 
 func clientCredentialsFlow(domain string, consumerKey string, consumerSecret string) (*authentication, error) {
 	payload := url.Values{
-		"grant_type":    {"client_credentials"},
+		"grant_type":    {grantTypeClientCredentials},
 		"client_id":     {consumerKey},
 		"client_secret": {consumerSecret},
 	}
@@ -90,3 +110,11 @@ func clientCredentialsFlow(domain string, consumerKey string, consumerSecret str
 	}
 	return auth, nil
 }
+
+func setAccessToken(domain string, accessToken string) (*authentication, error) {
+	auth := &authentication{InstanceUrl: domain, AccessToken: accessToken}
+	if err := validateSession(*auth); err != nil {
+		return nil, err
+	}
+	return auth, nil
+}

auth_test.go

@@ -2,7 +2,6 @@ package salesforce
 
 import (
 	"net/http"
-	"net/http/httptest"
 	"reflect"
 	"testing"
 )
@@ -53,9 +52,7 @@ func Test_usernamePasswordFlow(t *testing.T) {
 	server, _ := setupTestServer(auth, http.StatusOK)
 	defer server.Close()
 
-	badServer := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-		w.WriteHeader(http.StatusForbidden)
-	}))
+	badServer, _ := setupTestServer(auth, http.StatusForbidden)
 	defer badServer.Close()
 
 	type args struct {
@@ -124,9 +121,7 @@ func Test_clientCredentialsFlow(t *testing.T) {
 	server, _ := setupTestServer(auth, http.StatusOK)
 	defer server.Close()
 
-	badServer := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-		w.WriteHeader(http.StatusForbidden)
-	}))
+	badServer, _ := setupTestServer(auth, http.StatusForbidden)
 	defer badServer.Close()
 
 	type args struct {
@@ -174,3 +169,67 @@ func Test_clientCredentialsFlow(t *testing.T) {
 		})
 	}
 }
+
+func Test_setAccessToken(t *testing.T) {
+	auth := authentication{
+		InstanceUrl: "example.com",
+		AccessToken: "1234",
+	}
+	server, _ := setupTestServer(auth, http.StatusOK)
+	defer server.Close()
+
+	badServer, _ := setupTestServer(auth, http.StatusForbidden)
+	defer badServer.Close()
+
+	type args struct {
+		domain      string
+		accessToken string
+	}
+	tests := []struct {
+		name    string
+		args    args
+		want    *authentication
+		wantErr bool
+	}{
+		{
+			name: "authentication_success",
+			args: args{
+				domain:      server.URL,
+				accessToken: "1234",
+			},
+			want:    &auth,
+			wantErr: false,
+		},
+		{
+			name: "authentication_fail_http_error",
+			args: args{
+				domain:      badServer.URL,
+				accessToken: "1234",
+			},
+			want:    nil,
+			wantErr: true,
+		},
+		{
+			name: "authentication_fail_no_token",
+			args: args{
+				domain:      server.URL,
+				accessToken: "",
+			},
+			want:    nil,
+			wantErr: true,
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			got, err := setAccessToken(tt.args.domain, tt.args.accessToken)
+			if (err != nil) != tt.wantErr {
+				t.Errorf("setAccessToken() error = %v, wantErr %v", err, tt.wantErr)
+				return
+			}
+			if (tt.want == nil && !reflect.DeepEqual(got, tt.want)) ||
+				(tt.want != nil && !reflect.DeepEqual(got.AccessToken, tt.want.AccessToken)) {
+				t.Errorf("setAccessToken() = %v, want %v", got, tt.want)
+			}
+		})
+	}
+}

salesforce.go

@@ -192,14 +192,6 @@ func Init(creds Creds) (*Salesforce, error) {
 	var auth *authentication
 	var err error
 	if creds != (Creds{}) && creds.Domain != "" && creds.ConsumerKey != "" && creds.ConsumerSecret != "" &&
-		(creds.Username == "" || creds.Password == "" || creds.SecurityToken == "") {
-
-		auth, err = clientCredentialsFlow(
-			creds.Domain,
-			creds.ConsumerKey,
-			creds.ConsumerSecret,
-		)
-	} else if creds != (Creds{}) && creds.Domain != "" && creds.ConsumerKey != "" && creds.ConsumerSecret != "" &&
 		creds.Username != "" && creds.Password != "" && creds.SecurityToken != "" {
 
 		auth, err = usernamePasswordFlow(
@@ -210,6 +202,17 @@ func Init(creds Creds) (*Salesforce, error) {
 			creds.ConsumerKey,
 			creds.ConsumerSecret,
 		)
+	} else if creds != (Creds{}) && creds.Domain != "" && creds.ConsumerKey != "" && creds.ConsumerSecret != "" {
+		auth, err = clientCredentialsFlow(
+			creds.Domain,
+			creds.ConsumerKey,
+			creds.ConsumerSecret,
+		)
+	} else if creds != (Creds{}) && creds.AccessToken != "" {
+		auth, err = setAccessToken(
+			creds.Domain,
+			creds.AccessToken,
+		)
 	}
 
 	if err != nil {

salesforce_test.go

@@ -378,6 +378,24 @@ func TestInit(t *testing.T) {
 			want:    &Salesforce{auth: &sfAuth},
 			wantErr: false,
 		},
+		{
+			name: "authentication_client_credentials",
+			args: args{creds: Creds{
+				Domain:         server.URL,
+				ConsumerKey:    "key",
+				ConsumerSecret: "secret",
+			}},
+			want:    &Salesforce{auth: &sfAuth},
+			wantErr: false,
+		},
+		{
+			name: "authentication_access_token",
+			args: args{creds: Creds{
+				Domain:      server.URL,
+				AccessToken: "1234",
+			}},
+			wantErr: false,
+		},
 	}
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
@@ -386,7 +404,7 @@ func TestInit(t *testing.T) {
 				t.Errorf("Init() error = %v, wantErr %v", err, tt.wantErr)
 				return
 			}
-			if !reflect.DeepEqual(got, tt.want) {
+			if tt.want != nil && !tt.wantErr && !reflect.DeepEqual(got, tt.want) {
 				t.Errorf("Init() = %v, want %v", *got.auth, *tt.want.auth)
 			}
 		})