[chore] simplify generating log entry caller information (#863)

* vastly simplify logging caller information

Signed-off-by: kim <grufwub@gmail.com>

* fix failing test due to multiple calls to processor.Start()

Signed-off-by: kim <grufwub@gmail.com>

Signed-off-by: kim <grufwub@gmail.com>

internal/api/s2s/user/inboxpost_test.go

@@ -292,15 +292,6 @@ func (suite *InboxPostTestSuite) TestPostUpdate() {
 	federator := testrig.NewTestFederator(suite.db, tc, suite.storage, suite.mediaManager, fedWorker)
 	emailSender := testrig.NewEmailSender("../../../../web/template/", nil)
 	processor := testrig.NewTestProcessor(suite.db, suite.storage, federator, emailSender, suite.mediaManager, clientWorker, fedWorker)
-	if err := processor.Start(); err != nil {
-		panic(err)
-	}
-	defer func() {
-		if err := processor.Stop(); err != nil {
-			panic(err)
-		}
-	}()
-
 	userModule := user.New(processor).(*user.Module)
 	suite.NoError(processor.Start())
 

internal/log/caller.go

@@ -21,69 +21,39 @@ package log
 import (
 	"runtime"
 	"strings"
-	"sync"
-)
-
-var (
-	// fnCache is a cache of PCs to their calculated function names.
-	fnCache = map[uintptr]string{}
-
-	// strCache is a cache of strings to the originally allocated version
-	// of that string contents. so we don't have hundreds of the same instances
-	// of string floating around in memory.
-	strCache = map[string]string{}
-
-	// cacheMu protects fnCache and strCache.
-	cacheMu sync.Mutex
 )
 
 // Caller fetches the calling function name, skipping 'depth'. Results are cached per PC.
 func Caller(depth int) string {
-	var rpc [1]uintptr
-
-	// Fetch pcs of callers
-	n := runtime.Callers(depth, rpc[:])
+	var pcs [1]uintptr
 
-	if n > 0 {
-		// Look for value in cache
-		cacheMu.Lock()
-		fn, ok := fnCache[rpc[0]]
-		cacheMu.Unlock()
+	// Fetch calling function using calldepth
+	_ = runtime.Callers(depth, pcs[:])
+	fn := runtime.FuncForPC(pcs[0])
 
-		if ok {
-			return fn
-		}
-
-		// Fetch frame info for caller pc
-		frame, _ := runtime.CallersFrames(rpc[:]).Next()
+	if fn == nil {
+		return ""
+	}
 
-		if frame.PC != 0 {
-			name := frame.Function
+	// return formatted name
+	return callername(fn)
+}
 
-			// Drop all but the package name and function name, no mod path
-			if idx := strings.LastIndex(name, "/"); idx >= 0 {
-				name = name[idx+1:]
-			}
+// callername generates a human-readable calling function name.
+func callername(fn *runtime.Func) string {
+	name := fn.Name()
 
-			// Drop any generic type parameter markers
-			if idx := strings.Index(name, "[...]"); idx >= 0 {
-				name = name[:idx] + name[idx+5:]
-			}
+	// Drop all but the package name and function name, no mod path
+	if idx := strings.LastIndex(name, "/"); idx >= 0 {
+		name = name[idx+1:]
+	}
 
-			// Cache this func name
-			cacheMu.Lock()
-			fn, ok := strCache[name]
-			if !ok {
-				// Cache ptr to this allocated str
-				strCache[name] = name
-				fn = name
-			}
-			fnCache[rpc[0]] = fn
-			cacheMu.Unlock()
+	const params = `[...]`
 
-			return fn
-		}
+	// Drop any generic type parameter markers
+	if idx := strings.Index(name, params); idx >= 0 {
+		name = name[:idx] + name[idx+len(params):]
 	}
 
-	return "???"
+	return name
 }