Scope transactions to endpoints (#2799)

To avoid returning results from e.g. `/redact` on `/sendToDevice`
requests.
Takes the raw URL path and uses `filepath.Dir` to remove the `txnID`
(file) from it.

Co-authored-by: Neil Alexander <neilalexander@users.noreply.github.com>

2 files changed, 44 insertions, 14 deletions

diff --git a/internal/transactions/transactions.go b/internal/transactions/transactions.go
index d2eb0f27..7ff6f504 100644
--- a/internal/transactions/transactions.go
+++ b/internal/transactions/transactions.go
@@ -13,6 +13,8 @@
 package transactions
 
 import (
+	"net/url"
+	"path/filepath"
 	"sync"
 	"time"
 
@@ -29,6 +31,7 @@ type txnsMap map[CacheKey]*util.JSONResponse
 type CacheKey struct {
 	AccessToken string
 	TxnID       string
+	Endpoint    string
 }
 
 // Cache represents a temporary store for response entries.
@@ -57,14 +60,14 @@ func NewWithCleanupPeriod(cleanupPeriod time.Duration) *Cache {
 	return &t
 }
 
-// FetchTransaction looks up an entry for the (accessToken, txnID) tuple in Cache.
+// FetchTransaction looks up an entry for the (accessToken, txnID, req.URL) tuple in Cache.
 // Looks in both the txnMaps.
 // Returns (JSON response, true) if txnID is found, else the returned bool is false.
-func (t *Cache) FetchTransaction(accessToken, txnID string) (*util.JSONResponse, bool) {
+func (t *Cache) FetchTransaction(accessToken, txnID string, u *url.URL) (*util.JSONResponse, bool) {
 	t.RLock()
 	defer t.RUnlock()
 	for _, txns := range t.txnsMaps {
-		res, ok := txns[CacheKey{accessToken, txnID}]
+		res, ok := txns[CacheKey{accessToken, txnID, filepath.Dir(u.Path)}]
 		if ok {
 			return res, true
 		}
@@ -72,13 +75,12 @@ func (t *Cache) FetchTransaction(accessToken, txnID string) (*util.JSONResponse,
 	return nil, false
 }
 
-// AddTransaction adds an entry for the (accessToken, txnID) tuple in Cache.
+// AddTransaction adds an entry for the (accessToken, txnID, req.URL) tuple in Cache.
 // Adds to the front txnMap.
-func (t *Cache) AddTransaction(accessToken, txnID string, res *util.JSONResponse) {
+func (t *Cache) AddTransaction(accessToken, txnID string, u *url.URL, res *util.JSONResponse) {
 	t.Lock()
 	defer t.Unlock()
-
-	t.txnsMaps[0][CacheKey{accessToken, txnID}] = res
+	t.txnsMaps[0][CacheKey{accessToken, txnID, filepath.Dir(u.Path)}] = res
 }
 
 // cacheCleanService is responsible for cleaning up entries after cleanupPeriod.
diff --git a/internal/transactions/transactions_test.go b/internal/transactions/transactions_test.go
index aa837f76..c552550a 100644
--- a/internal/transactions/transactions_test.go
+++ b/internal/transactions/transactions_test.go
@@ -14,6 +14,9 @@ package transactions
 
 import (
 	"net/http"
+	"net/url"
+	"path/filepath"
+	"reflect"
 	"strconv"
 	"testing"
 
@@ -24,6 +27,16 @@ type fakeType struct {
 	ID string `json:"ID"`
 }
 
+func TestCompare(t *testing.T) {
+	u1, _ := url.Parse("/send/1?accessToken=123")
+	u2, _ := url.Parse("/send/1")
+	c1 := CacheKey{"1", "2", filepath.Dir(u1.Path)}
+	c2 := CacheKey{"1", "2", filepath.Dir(u2.Path)}
+	if !reflect.DeepEqual(c1, c2) {
+		t.Fatalf("Cache keys differ: %+v <> %+v", c1, c2)
+	}
+}
+
 var (
 	fakeAccessToken  = "aRandomAccessToken"
 	fakeAccessToken2 = "anotherRandomAccessToken"
@@ -34,23 +47,28 @@ var (
 	fakeResponse2 = &util.JSONResponse{
 		Code: http.StatusOK, JSON: fakeType{ID: "1"},
 	}
+	fakeResponse3 = &util.JSONResponse{
+		Code: http.StatusOK, JSON: fakeType{ID: "2"},
+	}
 )
 
 // TestCache creates a New Cache and tests AddTransaction & FetchTransaction
 func TestCache(t *testing.T) {
 	fakeTxnCache := New()
-	fakeTxnCache.AddTransaction(fakeAccessToken, fakeTxnID, fakeResponse)
+	u, _ := url.Parse("")
+	fakeTxnCache.AddTransaction(fakeAccessToken, fakeTxnID, u, fakeResponse)
 
 	// Add entries for noise.
 	for i := 1; i <= 100; i++ {
 		fakeTxnCache.AddTransaction(
 			fakeAccessToken,
 			fakeTxnID+strconv.Itoa(i),
+			u,
 			&util.JSONResponse{Code: http.StatusOK, JSON: fakeType{ID: strconv.Itoa(i)}},
 		)
 	}
 
-	testResponse, ok := fakeTxnCache.FetchTransaction(fakeAccessToken, fakeTxnID)
+	testResponse, ok := fakeTxnCache.FetchTransaction(fakeAccessToken, fakeTxnID, u)
 	if !ok {
 		t.Error("Failed to retrieve entry for txnID: ", fakeTxnID)
 	} else if testResponse.JSON != fakeResponse.JSON {
@@ -59,20 +77,30 @@ func TestCache(t *testing.T) {
 }
 
 // TestCacheScope ensures transactions with the same transaction ID are not shared
-// across multiple access tokens.
+// across multiple access tokens and endpoints.
 func TestCacheScope(t *testing.T) {
 	cache := New()
-	cache.AddTransaction(fakeAccessToken, fakeTxnID, fakeResponse)
-	cache.AddTransaction(fakeAccessToken2, fakeTxnID, fakeResponse2)
+	sendEndpoint, _ := url.Parse("/send/1?accessToken=test")
+	sendToDeviceEndpoint, _ := url.Parse("/sendToDevice/1")
+	cache.AddTransaction(fakeAccessToken, fakeTxnID, sendEndpoint, fakeResponse)
+	cache.AddTransaction(fakeAccessToken2, fakeTxnID, sendEndpoint, fakeResponse2)
+	cache.AddTransaction(fakeAccessToken2, fakeTxnID, sendToDeviceEndpoint, fakeResponse3)
 
-	if res, ok := cache.FetchTransaction(fakeAccessToken, fakeTxnID); !ok {
+	if res, ok := cache.FetchTransaction(fakeAccessToken, fakeTxnID, sendEndpoint); !ok {
 		t.Errorf("failed to retrieve entry for (%s, %s)", fakeAccessToken, fakeTxnID)
 	} else if res.JSON != fakeResponse.JSON {
 		t.Errorf("Wrong cache entry for (%s, %s). Expected: %v; got: %v", fakeAccessToken, fakeTxnID, fakeResponse.JSON, res.JSON)
 	}
-	if res, ok := cache.FetchTransaction(fakeAccessToken2, fakeTxnID); !ok {
+	if res, ok := cache.FetchTransaction(fakeAccessToken2, fakeTxnID, sendEndpoint); !ok {
 		t.Errorf("failed to retrieve entry for (%s, %s)", fakeAccessToken, fakeTxnID)
 	} else if res.JSON != fakeResponse2.JSON {
 		t.Errorf("Wrong cache entry for (%s, %s). Expected: %v; got: %v", fakeAccessToken, fakeTxnID, fakeResponse2.JSON, res.JSON)
 	}
+
+	// Ensure the txnID is not shared across endpoints
+	if res, ok := cache.FetchTransaction(fakeAccessToken2, fakeTxnID, sendToDeviceEndpoint); !ok {
+		t.Errorf("failed to retrieve entry for (%s, %s)", fakeAccessToken, fakeTxnID)
+	} else if res.JSON != fakeResponse3.JSON {
+		t.Errorf("Wrong cache entry for (%s, %s). Expected: %v; got: %v", fakeAccessToken, fakeTxnID, fakeResponse2.JSON, res.JSON)
+	}
 }