normalize requests at API level before validation (#4136)

Today we only normalize and validate requests at the client side, but
only validate on the server side without normalizing first. This causes
inconsistencies and issues around optional fields, such as publishers.

## Example before the fix:
```
# hello.json
{
  "Job": {
    "Type": "batch",
    "Count": 1,
    "Tasks": [
      {
        "Name": "main",
        "Engine": {
          "Type": "docker",
          "Params": {
            "Image": "ubuntu",
            "Parameters": ["echo", "hello"]
          }
        }
      }
    ]
  }
}
```

```
 curl -X PUT localhost:1234/api/v1/orchestrator/jobs -H "Content-Type: application/json" -d @hello.json
{
  "error": "code=400, message=task main validation failed: publisher validation failed: nil spec config",
  "message": "task main validation failed: publisher validation failed: nil spec config"
}
```

## Example after the fix
```
→  curl -X PUT localhost:1234/api/v1/orchestrator/jobs -H "Content-Type: application/json" -d @hello.json

{
  "JobID": "j-26b215f9-582c-4374-80cb-fd079e73fc37",
  "EvaluationID": "36fd6f65-64fd-421b-a9ba-aaf86d876704",
  "Warnings": null
}
```

```
→ bacalhau job describe j-26b215f9-582c-4374-80cb-fd079e73fc37
ID            = j-26b215f9-582c-4374-80cb-fd079e73fc37
Name          = j-26b215f9-582c-4374-80cb-fd079e73fc37
Namespace     = default
Type          = batch
State         = Completed
Count         = 1
Created Time  = 2024-06-25 09:14:40
Modified Time = 2024-06-25 09:14:43
Version       = 0

Summary
Completed = 1

Job History
 TIME                 REV.  STATE      TOPIC       EVENT
 2024-06-25 11:14:40  1     Pending    Submission  Job submitted
 2024-06-25 11:14:40  2     Running
 2024-06-25 11:14:43  3     Completed

Executions
 ID          NODE ID     STATE      DESIRED  REV.  CREATED  MODIFIED  COMMENT
 e-ad7cc59d  n-6e8998ad  Completed  Stopped  6     14s ago  12s ago   Accepted job

Execution e-ad7cc59d History
 TIME                 REV.  STATE              TOPIC            EVENT
 2024-06-25 11:14:40  1     New
 2024-06-25 11:14:40  2     AskForBid
 2024-06-25 11:14:40  3     AskForBidAccepted  Requesting Node  Accepted job
 2024-06-25 11:14:40  4     AskForBidAccepted
 2024-06-25 11:14:40  5     BidAccepted
 2024-06-25 11:14:43  6     Completed

Standard Output
hello
```

```
→ bacalhau job describe j-26b215f9-582c-4374-80cb-fd079e73fc37 --output json --pretty | jq ".Job"
{
  "ID": "j-26b215f9-582c-4374-80cb-fd079e73fc37",
  "Name": "j-26b215f9-582c-4374-80cb-fd079e73fc37",
  "Namespace": "default",
  "Type": "batch",
  "Priority": 0,
  "Count": 1,
  "Constraints": [],
  "Meta": {
    "bacalhau.org/requester.id": "n-6e8998ad-e0b9-43e6-9ccb-47f05a780f4a"
  },
  "Labels": {},
  "Tasks": [
    {
      "Name": "main",
      "Engine": {
        "Type": "docker",
        "Params": {
          "Image": "ubuntu",
          "Parameters": [
            "echo",
            "hello"
          ]
        }
      },
      "Publisher": {
        "Type": ""
      },
      "Resources": {},
      "Network": {
        "Type": "None"
      },
      "Timeouts": {
        "TotalTimeout": 1800
      }
    }
  ],
  "State": {
    "StateType": "Completed"
  },
  "Version": 0,
  "Revision": 3,
  "CreateTime": 1719306880611865000,
  "ModifyTime": 1719306883073224000
}
```



Closes #3950

pkg/publicapi/apimodels/job.go

@@ -59,7 +59,7 @@ type GetJobResponse struct {
 	Executions *ListJobExecutionsResponse `json:"Executions,omitempty"`
 }
 
-// Normalize is used to33 canonicalize fields in the GetJobResponse.
+// Normalize is used to canonicalize fields in the GetJobResponse.
 func (r *GetJobResponse) Normalize() {
 	r.BaseGetResponse.Normalize()
 	if r.Job != nil {

pkg/publicapi/binder.go

@@ -0,0 +1,33 @@
+package publicapi
+
+import (
+	"github.com/labstack/echo/v4"
+)
+
+// normalizable is an interface that defines a Normalize method.
+type normalizable interface {
+	Normalize()
+}
+
+// NormalizeBinder is a custom binder that extends the default binder with normalization.
+type NormalizeBinder struct {
+	defaultBinder echo.Binder
+}
+
+// NewNormalizeBinder creates a new NormalizeBinder with the default binder.
+func NewNormalizeBinder() *NormalizeBinder {
+	return &NormalizeBinder{
+		defaultBinder: &echo.DefaultBinder{},
+	}
+}
+
+// Bind binds and validates the request body, then normalizes if it implements the normalizable interface.
+func (cb *NormalizeBinder) Bind(i interface{}, c echo.Context) error {
+	if err := cb.defaultBinder.Bind(i, c); err != nil {
+		return err
+	}
+	if normalizer, ok := i.(normalizable); ok {
+		normalizer.Normalize()
+	}
+	return nil
+}

pkg/publicapi/binder_test.go

@@ -0,0 +1,86 @@
+//go:build unit || !integration
+
+package publicapi
+
+import (
+	"net/http"
+	"net/http/httptest"
+	"strings"
+	"testing"
+
+	"github.com/labstack/echo/v4"
+	"github.com/stretchr/testify/suite"
+)
+
+// Mock struct that implements normalizable interface
+type mockNormalizableRequest struct {
+	Data string `json:"data" validate:"required"`
+}
+
+func (mr *mockNormalizableRequest) Normalize() {
+	mr.Data = strings.TrimSpace(mr.Data)
+}
+
+// Mock struct that does not implement normalizable interface
+type mockNonNormalizableRequest struct {
+	Data string `json:"data" validate:"required"`
+}
+
+// TestSuite struct for NormalizeBinder
+type NormalizeBinderTestSuite struct {
+	suite.Suite
+	e      *echo.Echo
+	binder *NormalizeBinder
+	rec    *httptest.ResponseRecorder
+}
+
+// SetupTest sets up the test environment
+func (s *NormalizeBinderTestSuite) SetupTest() {
+	s.e = echo.New()
+	s.binder = NewNormalizeBinder()
+	s.rec = httptest.NewRecorder()
+}
+
+// TestBindWithNormalization tests binding with normalization
+func (s *NormalizeBinderTestSuite) TestBindWithNormalization() {
+	echoContext := s.mockRequest(`{"data": " some data "}`)
+	mockReq := new(mockNormalizableRequest)
+	err := s.binder.Bind(mockReq, echoContext)
+
+	s.NoError(err)
+	s.Equal("some data", mockReq.Data)
+}
+
+// TestBindWithoutNormalization tests binding without normalization
+func (s *NormalizeBinderTestSuite) TestBindWithoutNormalization() {
+	echoContext := s.mockRequest(`{"data": " some data "}`)
+
+	mockReq := new(mockNonNormalizableRequest)
+	err := s.binder.Bind(mockReq, echoContext)
+
+	s.NoError(err)
+	s.Equal(" some data ", mockReq.Data)
+}
+
+// TestBindWithBadJSON tests binding with bad JSON
+func (s *NormalizeBinderTestSuite) TestBindWithBadJSON() {
+	echoContext := s.mockRequest(`{"data": " some data "`)
+
+	mockReq := new(mockNormalizableRequest)
+	err := s.binder.Bind(mockReq, echoContext)
+
+	s.Error(err)
+	s.Equal(400, err.(*echo.HTTPError).Code)
+	s.Equal("unexpected EOF", err.(*echo.HTTPError).Message)
+}
+
+func (s *NormalizeBinderTestSuite) mockRequest(body string) echo.Context {
+	req := httptest.NewRequest(http.MethodPost, "/", strings.NewReader(body))
+	req.Header.Set(echo.HeaderContentType, echo.MIMEApplicationJSON)
+	return s.e.NewContext(req, s.rec)
+}
+
+// TestNormalizeBinderSuite runs the test suite
+func TestNormalizeBinderSuite(t *testing.T) {
+	suite.Run(t, new(NormalizeBinderTestSuite))
+}

pkg/publicapi/server.go

@@ -86,7 +86,8 @@ func NewAPIServer(params ServerParams) (*Server, error) {
 		"/requester/websocket/events": "/api/v1/requester/websocket/events",
 	}
 
-	// set validator
+	// set custom binders and validators
+	server.Router.Binder = NewNormalizeBinder()
 	server.Router.Validator = NewCustomValidator()
 
 	// enable debug mode to get clearer error messages