add rest authorization header support

headers.go

@@ -0,0 +1,31 @@
+package rest
+
+import (
+	"fmt"
+	"net/http"
+)
+
+// IsAuthenticated returns true if the bearer token in a request's authorization is equal to a user-defined token.
+// This function always returns true if the user-defined token is empty i.e. no authentication required.
+func IsAuthenticated(req *http.Request, token string) bool {
+	if token == "" {
+		return true
+	}
+
+	read := ReadBearerToken(req)
+	return read == token
+}
+
+// ReadBearerToken reads the token portion of a bearer token in a request's authorization header.
+// This function returns an empty string if the header is not provided or is not a bearer token.
+func ReadBearerToken(req *http.Request) string {
+	header := req.Header.Get("authorization")
+	if len(header) > 8 {
+		bearer := header[0:7]
+		fmt.Println(bearer)
+		if bearer == "bearer " || bearer == "Bearer " {
+			return header[7:]
+		}
+	}
+	return ""
+}

headers_test.go

@@ -0,0 +1,73 @@
+package rest
+
+import (
+	"net/http"
+	"net/http/httptest"
+	"testing"
+)
+
+func TestIsAuthenticated(t *testing.T) {
+	type TestCase struct {
+		Req      *http.Request
+		Token    string
+		Expected bool
+	}
+
+	testCases := []TestCase{}
+
+	req := httptest.NewRequest("GET", "/", nil)
+	req.Header.Add("authorization", "bearer abcd")
+	testCases = append(testCases, TestCase{Req: req, Token: "abcd", Expected: true})
+
+	req = httptest.NewRequest("POST", "/", nil)
+	req.Header.Add("authorization", "Bearer defg hijk")
+	testCases = append(testCases, TestCase{Req: req, Token: "defg hijk", Expected: true})
+
+	req = httptest.NewRequest("DELETE", "/", nil)
+	testCases = append(testCases, TestCase{Req: req, Token: "", Expected: true})
+
+	req = httptest.NewRequest("GET", "/", nil)
+	testCases = append(testCases, TestCase{Req: req, Token: "lmno"})
+
+	req = httptest.NewRequest("GET", "/", nil)
+	req.Header.Add("authorization", "Bearer pqrs")
+	testCases = append(testCases, TestCase{Req: req, Expected: true})
+
+	for i, tc := range testCases {
+		t.Logf("(%d) Testing request authorization header against %q", i, tc.Token)
+
+		actual := IsAuthenticated(tc.Req, tc.Token)
+		if actual != tc.Expected {
+			t.Errorf("Expected %v, got %v", tc.Expected, actual)
+		}
+	}
+}
+
+func TestReadBearerToken(t *testing.T) {
+	type TestCase struct {
+		Req      *http.Request
+		Expected string
+	}
+
+	testCases := []TestCase{}
+
+	req := httptest.NewRequest("GET", "/", nil)
+	req.Header.Add("authorization", "bearer abcd")
+	testCases = append(testCases, TestCase{Req: req, Expected: "abcd"})
+
+	req = httptest.NewRequest("POST", "/", nil)
+	req.Header.Add("authorization", "Bearer defg hijk")
+	testCases = append(testCases, TestCase{Req: req, Expected: "defg hijk"})
+
+	req = httptest.NewRequest("DELETE", "/", nil)
+	testCases = append(testCases, TestCase{Req: req, Expected: ""})
+
+	for i, tc := range testCases {
+		t.Logf("(%d) Testing request authorization header against %q", i, tc.Expected)
+
+		actual := ReadBearerToken(tc.Req)
+		if actual != tc.Expected {
+			t.Errorf("Expected %q, got %q", tc.Expected, actual)
+		}
+	}
+}