fix: httpassert - unify accepted JSON paths for arrays (#293)

So far `JsonTemplate` and `JsonContentTemplate` did not accept e.g.
`$[0].field`, whereas e.g. `JsonPath` did.

Author: mgoetzegb

pkg/httpassert/request.go

@@ -11,7 +11,6 @@ import (
 	"net/http"
 	"net/http/httptest"
 	"os"
-	"strings"
 	"testing"
 	"time"
 
@@ -244,10 +243,7 @@ func (m *request) JsonContentTemplate(body string, values map[string]any) Reques
 	jsonBody := body
 	// apply provided values into the template
 	for k, v := range values {
-		// normalize JSONPath-like keys (convert $.a[0].b to a.0.b)
-		key := strings.TrimPrefix(k, "$.")
-		key = strings.ReplaceAll(key, "[", ".")
-		key = strings.ReplaceAll(key, "]", "")
+		key := normalizeJSONPath(k)
 
 		if !gjson.Get(jsonBody, key).Exists() {
 			assert.Fail(m.t, "Json key does not exist in template: "+k)

pkg/httpassert/request_test.go

@@ -157,7 +157,7 @@ func TestRequest(t *testing.T) {
 			StatusCode(http.StatusOK)
 	})
 
-	t.Run("JSON content template", func(t *testing.T) {
+	t.Run("JSON content template with object", func(t *testing.T) {
 		var content []byte
 		router := http.NewServeMux()
 		router.HandleFunc("/json", func(w http.ResponseWriter, r *http.Request) {
@@ -182,6 +182,32 @@ func TestRequest(t *testing.T) {
 
 		AssertJSONCanonicalEq(t, `{"n": {"foo": "bar","asd":"123"}}`, string(content))
 	})
+
+	t.Run("JSON content template with array", func(t *testing.T) {
+		var content []byte
+		router := http.NewServeMux()
+		router.HandleFunc("/json", func(w http.ResponseWriter, r *http.Request) {
+			bodyBytes, err := io.ReadAll(r.Body)
+			require.NoError(t, err)
+			content = bodyBytes
+			w.WriteHeader(http.StatusOK)
+		})
+
+		New(t, router).
+			Post("/json").
+			JsonContentTemplate(`[{
+				"n": {
+					"foo": "bar",
+					"asd": ""
+				}
+			}]`, map[string]any{
+				"$[0].n.asd": "123",
+			}).
+			Expect().
+			StatusCode(http.StatusOK)
+
+		AssertJSONCanonicalEq(t, `[{"n": {"foo": "bar","asd":"123"}}]`, string(content))
+	})
 }
 
 func TestExpectEventually(t *testing.T) {

pkg/httpassert/response.go

@@ -140,10 +140,7 @@ func (r *responseImpl) JsonTemplate(expectedJsonTemplate string, values map[stri
 
 	// apply provided values into the template
 	for k, v := range values {
-		// normalize JSONPath-like keys (convert $.a[0].b to a.0.b)
-		key := strings.TrimPrefix(k, "$.")
-		key = strings.ReplaceAll(key, "[", ".")
-		key = strings.ReplaceAll(key, "]", "")
+		key := normalizeJSONPath(k)
 
 		if !gjson.Get(expectedJson, key).Exists() {
 			assert.Fail(r.t, "Json key does not exist in template: "+k)
@@ -164,9 +161,7 @@ func (r *responseImpl) JsonTemplate(expectedJsonTemplate string, values map[stri
 			continue
 		}
 
-		key := strings.TrimPrefix(k, "$.")
-		key = strings.ReplaceAll(key, "[", ".")
-		key = strings.ReplaceAll(key, "]", "")
+		key := normalizeJSONPath(k)
 
 		if !gjson.Get(actual, key).Exists() {
 			assert.Fail(r.t, "Json key does not exist in template: "+k)
@@ -235,3 +230,14 @@ func (r *responseImpl) Log() Response {
 		r.response.Body)
 	return r
 }
+
+// normalizeJSONPath converts jsonpath syntax to gjson/sjson syntax.
+// E.g. convert $.a[0].b to a.0.b and $[0].a to 0.a
+// This allows a unified path syntax to the caller, regardless which library is used internally.
+func normalizeJSONPath(path string) string {
+	path = strings.ReplaceAll(path, "[", ".")
+	path = strings.ReplaceAll(path, "]", "")
+	path = strings.TrimPrefix(path, "$.")
+
+	return path
+}

pkg/httpassert/response_test.go

@@ -24,7 +24,7 @@ func TestResponse(t *testing.T) {
 			JsonFile(path)
 	})
 
-	t.Run("JsonTemplate value replacement and ignore handling", func(t *testing.T) {
+	t.Run("JsonTemplate value replacement and ignore handling with object", func(t *testing.T) {
 		router := http.NewServeMux()
 		router.HandleFunc("/api", func(w http.ResponseWriter, r *http.Request) {
 			w.Header().Set("Content-Type", "application/json")
@@ -77,6 +77,26 @@ func TestResponse(t *testing.T) {
 		})
 	})
 
+	t.Run("JsonTemplate value replacement with array", func(t *testing.T) {
+		router := http.NewServeMux()
+		router.HandleFunc("/api", func(w http.ResponseWriter, r *http.Request) {
+			w.Header().Set("Content-Type", "application/json")
+			w.WriteHeader(http.StatusOK)
+			_, err := fmt.Fprint(w, `[{"id":42,"name":"Greenbone","version":"1.0.0","tags":["alpha","beta"]}]`)
+			require.NoError(t, err)
+		})
+
+		New(t, router).Get("/api").
+			Expect().
+			JsonTemplate(`[{"id":0,"name":"","version":"","tags":["x","y"]}]`, map[string]any{
+				"$[0].id":      42,
+				"$[0].name":    "Greenbone",
+				"$[0].tags[0]": "alpha",
+				"$[0].tags[1]": "beta",
+				"$[0].version": "1.0.0",
+			})
+	})
+
 	t.Run("GetBody returns non-empty", func(t *testing.T) {
 		body := request.Post("/json").
 			Expect().