Accumulated changes for message queue (#6600)

* rename

* set agent address

* refactor

* add agent sub

* pub messages

* grpc new client

* can publish records via agent

* send init message with session id

* fmt

* check cancelled request while waiting

* use sessionId

* handle possible nil stream

* subscriber process messages

* separate debug port

* use atomic int64

* less logs

* minor

* skip io.EOF

* rename

* remove unused

* use saved offsets

* do not reuse session, since always session id is new after restart

remove last active ts from SessionEntry

* simplify printing

* purge unused

* just proxy the subscription, skipping the session step

* adjust offset types

* subscribe offset type and possible value

* start after the known tsns

* avoid wrongly set startPosition

* move

* remove

* refactor

* typo

* fix

* fix changed path

other/mq_client_example/example/my_record.go

@@ -0,0 +1,56 @@
+package example
+
+import (
+	"github.com/seaweedfs/seaweedfs/weed/mq/schema"
+	"github.com/seaweedfs/seaweedfs/weed/pb/schema_pb"
+)
+
+type MyRecord struct {
+	Key    []byte
+	Field1 []byte
+	Field2 string
+	Field3 int32
+	Field4 int64
+	Field5 float32
+	Field6 float64
+	Field7 bool
+}
+
+func MyRecordType() *schema_pb.RecordType {
+	return schema.RecordTypeBegin().
+		WithField("key", schema.TypeBytes).
+		WithField("field1", schema.TypeBytes).
+		WithField("field2", schema.TypeString).
+		WithField("field3", schema.TypeInt32).
+		WithField("field4", schema.TypeInt64).
+		WithField("field5", schema.TypeFloat).
+		WithField("field6", schema.TypeDouble).
+		WithField("field7", schema.TypeBoolean).
+		RecordTypeEnd()
+}
+
+func (r *MyRecord) ToRecordValue() *schema_pb.RecordValue {
+	return schema.RecordBegin().
+		SetBytes("key", r.Key).
+		SetBytes("field1", r.Field1).
+		SetString("field2", r.Field2).
+		SetInt32("field3", r.Field3).
+		SetInt64("field4", r.Field4).
+		SetFloat("field5", r.Field5).
+		SetDouble("field6", r.Field6).
+		SetBool("field7", r.Field7).
+		RecordEnd()
+}
+
+func FromRecordValue(recordValue *schema_pb.RecordValue) *MyRecord {
+	return &MyRecord{
+		Key:    recordValue.Fields["key"].GetBytesValue(),
+		Field1: recordValue.Fields["field1"].GetBytesValue(),
+		Field2: recordValue.Fields["field2"].GetStringValue(),
+		Field3: recordValue.Fields["field3"].GetInt32Value(),
+		Field4: recordValue.Fields["field4"].GetInt64Value(),
+		Field5: recordValue.Fields["field5"].GetFloatValue(),
+		Field6: recordValue.Fields["field6"].GetDoubleValue(),
+		Field7: recordValue.Fields["field7"].GetBoolValue(),
+	}
+}