1// Copyright 2015 The etcd Authors
2//
3// Licensed under the Apache License, Version 2.0 (the "License");
4// you may not use this file except in compliance with the License.
5// You may obtain a copy of the License at
6//
7//     http://www.apache.org/licenses/LICENSE-2.0
8//
9// Unless required by applicable law or agreed to in writing, software
10// distributed under the License is distributed on an "AS IS" BASIS,
11// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12// See the License for the specific language governing permissions and
13// limitations under the License.
14
15package client
16
17import "net/rpc"
18
19type Status struct {
20	// State gives the human-readable status of an agent (e.g., "started" or "terminated")
21	State string
22
23	// TODO: gather more informations
24	// TODO: memory usage, raft information, etc..
25}
26
27type Agent interface {
28	ID() uint64
29	// Start starts a new etcd with the given args on the agent machine.
30	Start(args ...string) (int, error)
31	// Stop stops the existing etcd the agent started.
32	Stop() error
33	// Restart restarts the existing etcd the agent stopped.
34	Restart() (int, error)
35	// Cleanup stops the exiting etcd the agent started, then archives log and its data dir.
36	Cleanup() error
37	// Terminate stops the exiting etcd the agent started and removes its data dir.
38	Terminate() error
39	// DropPort drops all network packets at the given port.
40	DropPort(port int) error
41	// RecoverPort stops dropping all network packets at the given port.
42	RecoverPort(port int) error
43	// SetLatency slows down network by introducing latency.
44	SetLatency(ms, rv int) error
45	// RemoveLatency removes latency introduced by SetLatency.
46	RemoveLatency() error
47	// Status returns the status of etcd on the agent
48	Status() (Status, error)
49}
50
51type agent struct {
52	endpoint  string
53	rpcClient *rpc.Client
54}
55
56func NewAgent(endpoint string) (Agent, error) {
57	c, err := rpc.DialHTTP("tcp", endpoint)
58	if err != nil {
59		return nil, err
60	}
61	return &agent{endpoint, c}, nil
62}
63
64func (a *agent) Start(args ...string) (int, error) {
65	var pid int
66	err := a.rpcClient.Call("Agent.RPCStart", args, &pid)
67	if err != nil {
68		return -1, err
69	}
70	return pid, nil
71}
72
73func (a *agent) Stop() error {
74	return a.rpcClient.Call("Agent.RPCStop", struct{}{}, nil)
75}
76
77func (a *agent) Restart() (int, error) {
78	var pid int
79	err := a.rpcClient.Call("Agent.RPCRestart", struct{}{}, &pid)
80	if err != nil {
81		return -1, err
82	}
83	return pid, nil
84}
85
86func (a *agent) Cleanup() error {
87	return a.rpcClient.Call("Agent.RPCCleanup", struct{}{}, nil)
88}
89
90func (a *agent) Terminate() error {
91	return a.rpcClient.Call("Agent.RPCTerminate", struct{}{}, nil)
92}
93
94func (a *agent) DropPort(port int) error {
95	return a.rpcClient.Call("Agent.RPCDropPort", port, nil)
96}
97
98func (a *agent) RecoverPort(port int) error {
99	return a.rpcClient.Call("Agent.RPCRecoverPort", port, nil)
100}
101
102func (a *agent) SetLatency(ms, rv int) error {
103	return a.rpcClient.Call("Agent.RPCSetLatency", []int{ms, rv}, nil)
104}
105
106func (a *agent) RemoveLatency() error {
107	return a.rpcClient.Call("Agent.RPCRemoveLatency", struct{}{}, nil)
108}
109
110func (a *agent) Status() (Status, error) {
111	var s Status
112	err := a.rpcClient.Call("Agent.RPCStatus", struct{}{}, &s)
113	return s, err
114}
115
116func (a *agent) ID() uint64 {
117	panic("not implemented")
118}
119