From d63403f95aaf732660ffbe0799968e4cc1156573 Mon Sep 17 00:00:00 2001
From: Shahzad Lone <shahzadlone@gmail.com>
Date: Mon, 21 Oct 2024 20:14:40 +0400
Subject: [PATCH]  PR(ADHERE): Adhere to code review - mustify datastore.Txn

---
 http/errors.go     | 23 +++++++++++------------
 http/handler.go    |  7 +------
 http/handler_tx.go | 17 +++--------------
 http/utils.go      |  8 ++++++++
 4 files changed, 23 insertions(+), 32 deletions(-)

diff --git a/http/errors.go b/http/errors.go
index 0c626974db..aa6d6537ac 100644
--- a/http/errors.go
+++ b/http/errors.go
@@ -29,18 +29,17 @@ const (
 // This list is incomplete. Undefined errors may also be returned.
 // Errors returned from this package may be tested against these errors with errors.Is.
 var (
-	ErrNoListener                  = errors.New("cannot serve with no listener")
-	ErrNoEmail                     = errors.New("email address must be specified for tls with autocert")
-	ErrInvalidRequestBody          = errors.New("invalid request body")
-	ErrStreamingNotSupported       = errors.New("streaming not supported")
-	ErrMigrationNotFound           = errors.New("migration not found")
-	ErrMissingRequest              = errors.New("missing request")
-	ErrInvalidTransactionId        = errors.New("invalid transaction id")
-	ErrInvalidDataStoreTransaction = errors.New("invalid datastore transaction")
-	ErrP2PDisabled                 = errors.New("p2p network is disabled")
-	ErrMethodIsNotImplemented      = errors.New(errMethodIsNotImplemented)
-	ErrMissingIdentityPrivateKey   = errors.New("identity has no private key")
-	ErrMissingIdentityPublicKey    = errors.New("identity has no public key")
+	ErrNoListener                = errors.New("cannot serve with no listener")
+	ErrNoEmail                   = errors.New("email address must be specified for tls with autocert")
+	ErrInvalidRequestBody        = errors.New("invalid request body")
+	ErrStreamingNotSupported     = errors.New("streaming not supported")
+	ErrMigrationNotFound         = errors.New("migration not found")
+	ErrMissingRequest            = errors.New("missing request")
+	ErrInvalidTransactionId      = errors.New("invalid transaction id")
+	ErrP2PDisabled               = errors.New("p2p network is disabled")
+	ErrMethodIsNotImplemented    = errors.New(errMethodIsNotImplemented)
+	ErrMissingIdentityPrivateKey = errors.New("identity has no private key")
+	ErrMissingIdentityPublicKey  = errors.New("identity has no public key")
 )
 
 type errorResponse struct {
diff --git a/http/handler.go b/http/handler.go
index a3f4ae4d19..336dfc54d3 100644
--- a/http/handler.go
+++ b/http/handler.go
@@ -102,12 +102,7 @@ func (h *Handler) Transaction(id uint64) (datastore.Txn, error) {
 		return nil, ErrInvalidTransactionId
 	}
 
-	dsTxn, ok := tx.(datastore.Txn)
-	if !ok {
-		return nil, ErrInvalidDataStoreTransaction
-	}
-
-	return dsTxn, nil
+	return mustGetDataStoreTxn(tx), nil
 }
 
 func (h *Handler) ServeHTTP(w http.ResponseWriter, req *http.Request) {
diff --git a/http/handler_tx.go b/http/handler_tx.go
index e4ce231642..e1ac38376c 100644
--- a/http/handler_tx.go
+++ b/http/handler_tx.go
@@ -16,8 +16,6 @@ import (
 
 	"github.com/getkin/kin-openapi/openapi3"
 	"github.com/go-chi/chi/v5"
-
-	"github.com/sourcenetwork/defradb/datastore"
 )
 
 type txHandler struct{}
@@ -68,12 +66,7 @@ func (h *txHandler) Commit(rw http.ResponseWriter, req *http.Request) {
 		return
 	}
 
-	dsTxn, ok := txVal.(datastore.Txn)
-	if !ok {
-		responseJSON(rw, http.StatusBadRequest, errorResponse{ErrInvalidDataStoreTransaction})
-		return
-	}
-
+	dsTxn := mustGetDataStoreTxn(txVal)
 	err = dsTxn.Commit(req.Context())
 	if err != nil {
 		responseJSON(rw, http.StatusBadRequest, errorResponse{err})
@@ -97,13 +90,9 @@ func (h *txHandler) Discard(rw http.ResponseWriter, req *http.Request) {
 		return
 	}
 
-	dsTxn, ok := txVal.(datastore.Txn)
-	if !ok {
-		responseJSON(rw, http.StatusBadRequest, errorResponse{ErrInvalidDataStoreTransaction})
-		return
-	}
-
+	dsTxn := mustGetDataStoreTxn(txVal)
 	dsTxn.Discard(req.Context())
+
 	rw.WriteHeader(http.StatusOK)
 }
 
diff --git a/http/utils.go b/http/utils.go
index 9734058748..d371c802e6 100644
--- a/http/utils.go
+++ b/http/utils.go
@@ -17,6 +17,7 @@ import (
 	"sync"
 
 	"github.com/sourcenetwork/defradb/client"
+	"github.com/sourcenetwork/defradb/datastore"
 )
 
 const (
@@ -67,6 +68,13 @@ func mustGetContextClientStore(req *http.Request) client.Store {
 	return req.Context().Value(dbContextKey).(client.Store) //nolint:forcetypeassert
 }
 
+// mustGetDataStoreTxn returns the datastore transaction or panics.
+//
+// This should only be called from functions within the http package.
+func mustGetDataStoreTxn(tx any) datastore.Txn {
+	return tx.(datastore.Txn) //nolint:forcetypeassert
+}
+
 // tryGetContextClientP2P returns the P2P client from the http request context and a boolean
 // indicating if p2p was enabled.
 //