Add unit tests for middleware, models, services, handlers, and repository helpers

internal/handler/handler_test.go

@@ -0,0 +1,114 @@
+package handler
+
+import (
+	"bytes"
+	"encoding/json"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+)
+
+func TestHealthHandler(t *testing.T) {
+	h := NewHealthHandler()
+	req := httptest.NewRequest("GET", "/health", nil)
+	rr := httptest.NewRecorder()
+	h.Health(rr, req)
+
+	if rr.Code != http.StatusOK {
+		t.Errorf("expected 200, got %d", rr.Code)
+	}
+
+	var resp map[string]string
+	json.NewDecoder(rr.Body).Decode(&resp)
+	if resp["status"] != "ok" {
+		t.Errorf("expected status ok, got %s", resp["status"])
+	}
+	if resp["service"] != "homelab-api" {
+		t.Errorf("expected service homelab-api, got %s", resp["service"])
+	}
+}
+
+func TestWriteJSON(t *testing.T) {
+	rr := httptest.NewRecorder()
+	data := map[string]string{"hello": "world"}
+	writeJSON(rr, data, http.StatusCreated)
+
+	if rr.Code != http.StatusCreated {
+		t.Errorf("expected 201, got %d", rr.Code)
+	}
+	if ct := rr.Header().Get("Content-Type"); ct != "application/json" {
+		t.Errorf("expected application/json, got %s", ct)
+	}
+
+	var resp map[string]string
+	json.NewDecoder(rr.Body).Decode(&resp)
+	if resp["hello"] != "world" {
+		t.Errorf("expected world, got %s", resp["hello"])
+	}
+}
+
+func TestWriteError(t *testing.T) {
+	rr := httptest.NewRecorder()
+	writeError(rr, "something went wrong", http.StatusBadRequest)
+
+	if rr.Code != http.StatusBadRequest {
+		t.Errorf("expected 400, got %d", rr.Code)
+	}
+
+	var resp map[string]string
+	json.NewDecoder(rr.Body).Decode(&resp)
+	if resp["error"] != "something went wrong" {
+		t.Errorf("expected 'something went wrong', got %s", resp["error"])
+	}
+}
+
+func TestInterestHandler_Unauthorized(t *testing.T) {
+	h := &InterestHandler{secretKey: "my-secret"}
+
+	t.Run("missing key", func(t *testing.T) {
+		req := httptest.NewRequest("POST", "/internal/calculate-interest", nil)
+		rr := httptest.NewRecorder()
+		h.CalculateInterest(rr, req)
+		if rr.Code != http.StatusUnauthorized {
+			t.Errorf("expected 401, got %d", rr.Code)
+		}
+	})
+
+	t.Run("wrong key", func(t *testing.T) {
+		req := httptest.NewRequest("POST", "/internal/calculate-interest", nil)
+		req.Header.Set("X-Internal-Key", "wrong-key")
+		rr := httptest.NewRecorder()
+		h.CalculateInterest(rr, req)
+		if rr.Code != http.StatusUnauthorized {
+			t.Errorf("expected 401, got %d", rr.Code)
+		}
+	})
+}
+
+// Test request validation (without real service, just checking decoding)
+func TestDecodeInvalidJSON(t *testing.T) {
+	tests := []struct {
+		name    string
+		body    string
+		handler http.HandlerFunc
+	}{
+		{"invalid json", "{bad", func(w http.ResponseWriter, r *http.Request) {
+			var req struct{ Email string }
+			if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
+				writeError(w, "invalid request body", http.StatusBadRequest)
+				return
+			}
+		}},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			req := httptest.NewRequest("POST", "/test", bytes.NewBufferString(tt.body))
+			rr := httptest.NewRecorder()
+			tt.handler(rr, req)
+			if rr.Code != http.StatusBadRequest {
+				t.Errorf("expected 400, got %d", rr.Code)
+			}
+		})
+	}
+}