feat(testutil): add MockSlurm, MockMinIO, TestEnv and 37 integration tests

- mockminio: in-memory ObjectStorage with all 11 methods, thread-safe, SHA256 ETag, Range support
- mockslurm: httptest server with 11 Slurm REST API endpoints, job eviction from active to history queue
- testenv: one-line test environment factory (SQLite + MockSlurm + MockMinIO + all stores/services/handlers + httptest server)
- integration tests: 37 tests covering Jobs(5), Cluster(5), App(6), Upload(5), File(4), Folder(4), Task(4), E2E(1)
- no external dependencies, no existing files modified

cmd/server/integration_file_test.go

@@ -0,0 +1,170 @@
+package main
+
+import (
+	"encoding/json"
+	"fmt"
+	"io"
+	"net/http"
+	"testing"
+
+	"gcy_hpc_server/internal/model"
+	"gcy_hpc_server/internal/testutil/testenv"
+)
+
+// fileAPIResp mirrors server.APIResponse for file integration tests.
+type fileAPIResp struct {
+	Success bool            `json:"success"`
+	Data    json.RawMessage `json:"data,omitempty"`
+	Error   string          `json:"error,omitempty"`
+}
+
+// fileDecode parses an HTTP response body into fileAPIResp.
+func fileDecode(t *testing.T, body io.Reader) fileAPIResp {
+	t.Helper()
+	data, err := io.ReadAll(body)
+	if err != nil {
+		t.Fatalf("fileDecode: read body: %v", err)
+	}
+	var r fileAPIResp
+	if err := json.Unmarshal(data, &r); err != nil {
+		t.Fatalf("fileDecode: unmarshal: %v (body: %s)", err, string(data))
+	}
+	return r
+}
+
+func TestIntegration_File_List(t *testing.T) {
+	env := testenv.NewTestEnv(t)
+
+	// Upload a file so the list is non-empty.
+	env.UploadTestData("list_test.txt", []byte("hello list"))
+
+	resp := env.DoRequest("GET", "/api/v1/files", nil)
+	defer resp.Body.Close()
+
+	if resp.StatusCode != http.StatusOK {
+		t.Fatalf("expected 200, got %d", resp.StatusCode)
+	}
+
+	r := fileDecode(t, resp.Body)
+	if !r.Success {
+		t.Fatalf("response not success: %s", r.Error)
+	}
+
+	var listResp model.ListFilesResponse
+	if err := json.Unmarshal(r.Data, &listResp); err != nil {
+		t.Fatalf("unmarshal list response: %v", err)
+	}
+
+	if len(listResp.Files) == 0 {
+		t.Fatal("expected at least 1 file in list, got 0")
+	}
+
+	found := false
+	for _, f := range listResp.Files {
+		if f.Name == "list_test.txt" {
+			found = true
+			break
+		}
+	}
+	if !found {
+		t.Fatal("expected to find list_test.txt in file list")
+	}
+
+	if listResp.Total < 1 {
+		t.Fatalf("expected total >= 1, got %d", listResp.Total)
+	}
+	if listResp.Page < 1 {
+		t.Fatalf("expected page >= 1, got %d", listResp.Page)
+	}
+}
+
+func TestIntegration_File_Get(t *testing.T) {
+	env := testenv.NewTestEnv(t)
+
+	fileID, _ := env.UploadTestData("get_test.txt", []byte("hello get"))
+
+	resp := env.DoRequest("GET", fmt.Sprintf("/api/v1/files/%d", fileID), nil)
+	defer resp.Body.Close()
+
+	if resp.StatusCode != http.StatusOK {
+		t.Fatalf("expected 200, got %d", resp.StatusCode)
+	}
+
+	r := fileDecode(t, resp.Body)
+	if !r.Success {
+		t.Fatalf("response not success: %s", r.Error)
+	}
+
+	var fileResp model.FileResponse
+	if err := json.Unmarshal(r.Data, &fileResp); err != nil {
+		t.Fatalf("unmarshal file response: %v", err)
+	}
+
+	if fileResp.ID != fileID {
+		t.Fatalf("expected file ID %d, got %d", fileID, fileResp.ID)
+	}
+	if fileResp.Name != "get_test.txt" {
+		t.Fatalf("expected name get_test.txt, got %s", fileResp.Name)
+	}
+	if fileResp.Size != int64(len("hello get")) {
+		t.Fatalf("expected size %d, got %d", len("hello get"), fileResp.Size)
+	}
+}
+
+func TestIntegration_File_Download(t *testing.T) {
+	env := testenv.NewTestEnv(t)
+
+	content := []byte("hello world")
+	fileID, _ := env.UploadTestData("download_test.txt", content)
+
+	resp := env.DoRequest("GET", fmt.Sprintf("/api/v1/files/%d/download", fileID), nil)
+	defer resp.Body.Close()
+
+	if resp.StatusCode != http.StatusOK {
+		t.Fatalf("expected 200, got %d", resp.StatusCode)
+	}
+
+	body, err := io.ReadAll(resp.Body)
+	if err != nil {
+		t.Fatalf("read download body: %v", err)
+	}
+
+	if string(body) != string(content) {
+		t.Fatalf("downloaded content mismatch: got %q, want %q", string(body), string(content))
+	}
+
+	contentType := resp.Header.Get("Content-Type")
+	if contentType == "" {
+		t.Fatal("expected Content-Type header to be set")
+	}
+}
+
+func TestIntegration_File_Delete(t *testing.T) {
+	env := testenv.NewTestEnv(t)
+
+	fileID, _ := env.UploadTestData("delete_test.txt", []byte("hello delete"))
+
+	// Delete the file.
+	resp := env.DoRequest("DELETE", fmt.Sprintf("/api/v1/files/%d", fileID), nil)
+	defer resp.Body.Close()
+
+	if resp.StatusCode != http.StatusOK {
+		t.Fatalf("expected 200, got %d", resp.StatusCode)
+	}
+
+	r := fileDecode(t, resp.Body)
+	if !r.Success {
+		t.Fatalf("delete response not success: %s", r.Error)
+	}
+
+	// Verify the file is gone — GET should return 500 (internal error) or 404.
+	getResp := env.DoRequest("GET", fmt.Sprintf("/api/v1/files/%d", fileID), nil)
+	defer getResp.Body.Close()
+
+	if getResp.StatusCode == http.StatusOK {
+		gr := fileDecode(t, getResp.Body)
+		if gr.Success {
+			t.Fatal("expected file to be deleted, but GET still returns success")
+		}
+	}
+}