feat: adding telnet streamer support

docs/streamer_types.md

@@ -0,0 +1,75 @@
+# Streamer Types
+
+`gnetcli` supports different connection types (streamers) for connecting to network equipment: SSH, Telnet.
+
+## Supported Types
+
+### SSH (StreamerType_ssh)
+- **Value**: `0`
+- **Description**: Connection via SSH protocol (default)
+- **Default port**: 22
+- **Features**:
+  - SSH tunnel support (ProxyJump)
+  - SSH Control Files support
+  - SSH Agent support
+  - Private key authentication
+  - SFTP for file transfers
+
+### Telnet (StreamerType_telnet)
+- **Value**: `1`
+- **Description**: Connection via Telnet protocol
+- **Default port**: 23
+- **Features**:
+  - Plain text connection
+  - Username/password authentication
+  - Custom port support
+
+## API Usage
+
+### Via gRPC
+The streamer type is specified in host parameters:
+
+```protobuf
+message HostParams {
+  string host = 1;
+  Credentials credentials = 2;
+  int32 port = 3;
+  string device = 4;
+  string ip = 5;
+  StreamerType streamer_type = 6;  // SSH or Telnet
+}
+```
+
+### Example Request
+```json
+{
+  "host": "192.168.1.1",
+  "cmd": "show version",
+  "host_params": {
+    "streamer_type": 1,  // Use Telnet
+    "port": 23,
+    "credentials": {
+      "login": "admin",
+      "password": "password"
+    }
+  }
+}
+```
+
+## Choosing Streamer Type
+
+### SSH is recommended for:
+- Modern network equipment
+- Production environments where security is important
+- Devices supporting cryptographic authentication
+- Cases requiring file transfers
+
+### Telnet is suitable for:
+- Legacy equipment without SSH support
+- Lab and test environments
+- Devices with limited computational resources
+- Connection debugging and diagnostics
+
+## Default Configuration
+
+If `streamer_type` is not explicitly specified, SSH is used as the more secure default option.

go.mod

@@ -15,8 +15,8 @@ require (
 	go.uber.org/zap v1.26.0
 	golang.org/x/crypto v0.14.0
 	golang.org/x/exp v0.0.0-20230725093048-515e97ebf090
-	golang.org/x/net v0.16.0
 	golang.org/x/sync v0.4.0
+	golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1
 	google.golang.org/genproto/googleapis/api v0.0.0-20231002182017-d307bd883b97
 	google.golang.org/genproto/googleapis/rpc v0.0.0-20231002182017-d307bd883b97
 	google.golang.org/grpc v1.58.2
@@ -30,6 +30,7 @@ require (
 	github.com/golang/protobuf v1.5.3 // indirect
 	github.com/kr/fs v0.1.0 // indirect
 	github.com/pmezard/go-difflib v1.0.0 // indirect
+	golang.org/x/net v0.16.0 // indirect
 	golang.org/x/sys v0.13.0 // indirect
 	golang.org/x/text v0.13.0 // indirect
 	google.golang.org/genproto v0.0.0-20231002182017-d307bd883b97 // indirect

go.sum

@@ -161,6 +161,7 @@ golang.org/x/tools v0.1.12/go.mod h1:hNGJHUnrk76NpqgfD5Aqm5Crs+Hm0VOH/i9J2+nxYbc
 golang.org/x/xerrors v0.0.0-20190717185122-a985d3407aa7/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 golang.org/x/xerrors v0.0.0-20191011141410-1b5146add898/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
+golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1 h1:go1bK/D/BFZV2I8cIQd1NKEZ+0owSTG1fDTci4IqFcE=
 golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 google.golang.org/appengine v1.1.0/go.mod h1:EbEs0AVv82hx2wNQdGPgUI5lhzA/G0D9YwlJXL52JkM=
 google.golang.org/appengine v1.4.0/go.mod h1:xpcJRLb0r/rnEns0DIKYYv+WjYCduHsrkT7/EB5XEv4=

grpc_sdk/python/gnetclisdk/client.py

@@ -7,7 +7,7 @@
 from contextlib import asynccontextmanager
 from dataclasses import dataclass, field
 from functools import partial
-from typing import Any, AsyncIterator, List, Optional, Tuple, Dict, Callable
+from typing import Any, AsyncIterator, List, Optional, Tuple, Dict, Callable, Union
 
 import grpc
 from google.protobuf.message import Message
@@ -25,6 +25,9 @@
 SERVER_ENV = "GNETCLI_SERVER"
 GRPC_MAX_MESSAGE_LENGTH = 130 * 1024**2
 
+STREAMER_SSH = server_pb2.StreamerType_ssh
+STREAMER_TELNET = server_pb2.StreamerType_telnet
+
 default_grpc_options: List[Tuple[str, Any]] = [
     ("grpc.max_concurrent_streams", 900),
     ("grpc.max_send_message_length", GRPC_MAX_MESSAGE_LENGTH),
@@ -72,6 +75,7 @@ class HostParams:
     hostname: Optional[str] = None
     credentials: Optional[Credentials] = None
     ip: Optional[str] = None
+    streamer_type: Optional[int] = None
 
     def make_pb(self) -> server_pb2.HostParams:
         creds_pb: Optional[server_pb2.Credentials] = None
@@ -83,6 +87,7 @@ def make_pb(self) -> server_pb2.HostParams:
             credentials=creds_pb,
             device=self.device,
             ip=self.ip,
+            streamer_type=self.streamer_type if self.streamer_type is not None else server_pb2.StreamerType_ssh,
         )
         return pbcmd