图片 3

Consul初体验

 

Python调用RESTful:http://blog.akiban.com/get-restful-with-python/

Preface

本文就是参考该英文做了一下试验,后续补充一下翻译。

 

This post will take a look at our REST API by creating a Python script
to interact with the entity endpoint.

    Today I’m gonna implement a consul in
my environment to discover service of MySQL database and check whether
the master-slave is working normally.

One of the key benefits of using standard technologies, formats, and
protocols is the incredible amount of existing tooling that you get for
free. Since we’ve been busy building our new service, backed by our ever
changing database, we haven’t gotten around to client libraries yet.

 

However, we do speak JSON through REST over HTTPS. Every language
already has battle hardened libraries for working with those. For
Python, it doesn’t get much better than the requests library. Their
motto is HTTP for Humans and it makes working with RESTful services a
breeze.

Introduce

 
需求:

 

As in Schemaless SQL, we’ll be using a DataSpace with a single entity
named hopes.

    Consul is a tool like zookeeper which
can discover services we’ve registered on it.It’s just a simple binary
command which can run with simple configuration file(json
format).

On the service side, just copy and deploy the hopes DataSpace and make
note of the credentials.

 

On the client side, we just need to install the requests library.
$ pip install requests

official website:

 
Hello, World

https://www.consul.io/

We’ll be using an external JSON configuration file, named config.json,
for simplicity. Create the JSON files as below with real values from the
Deployments page.

 

{
  "host": "host",
  "port": "port",
  "user": "user",
  "pass": "pass"
}

Framework

The simplest endpoint exposed by the Akiban Server is version. It has no
dependencies and will always work if valid credentials are supplied.

 

We’ll start our script, named akiban_rest.py, with the code below to
load our configuration and execute a version request.

Hostname IP Port OS Version MySQL Version MySQL Role Consul Version Consul Role
zlm1 192.168.56.100 3306 CentOS 7.0 5.7.21 master Consul v1.2.2 server
zlm2 192.168.56.101 3306 CentOS 7.0 5.7.21 slave Consul v1.2.2 client
import json
import requests

config = {}
with open('config.json') as cfg:
  config = json.load(cfg)

resp = requests.get(
  'https://%s:%s/v1/version' % (config['host'], config['port']),
  auth = (config['user'], config['pass'])
)

print resp.text

* *

Running that will give output like below, though the specific
server_version may vary.
$ python akiban_rest.py

Procedure

[{“server_name”:”Akiban
Server”,”server_version”:”1.6.1-SNAPSHOT.2606″}]
Congrats! You’re now talking to the Akiban REST API. We’ll be wrapping
the rest of the Entity Resources to provide convenient access from the
command line.

 

 
Helpers

Download and install
consul.

A few helpers are in order. One for building the URI string, one for
pretty-printing our JSON response, and a variable for holding the
configured credentials.

 1 [root@zlm1 10:12:06 /vagrant]
 2 #wget https://releases.hashicorp.com/consul/1.2.2/consul_1.2.2_linux_amd64.zip
 3 --2018-08-16 10:02:13--  https://releases.hashicorp.com/consul/1.2.2/consul_1.2.2_linux_amd64.zip
 4 Resolving releases.hashicorp.com (releases.hashicorp.com)... 151.101.229.183, 2a04:4e42:36::439
 5 Connecting to releases.hashicorp.com (releases.hashicorp.com)|151.101.229.183|:443... connected.
 6 HTTP request sent, awaiting response... 200 OK
 7 Length: 18371676 (18M) [application/zip]
 8 Saving to: ‘consul_1.2.2_linux_amd64.zip’
 9 
10 100%[===========================================================================================================>] 18,371,676  38.8KB/s   in 6m 12s 
11 
12 2018-08-16 10:08:29 (48.3 KB/s) - ‘consul_1.2.2_linux_amd64.zip’ saved [18371676/18371676]
13 
14 [root@zlm1 10:14:12 /vagrant/consul_1.2.2_linux_amd64]
15 #ls -l
16 total 82431
17 -rwxrwxrwx 1 vagrant vagrant 84408501 Jul 30 18:04 consul //There's only a binary command in the unziped directory of zip file.
18 
19 [root@zlm1 10:26:18 /vagrant/consul_1.2.2_linux_amd64]
20 #mkdir /etc/consul.d
21 
22 [root@zlm1 10:26:36 /vagrant/consul_1.2.2_linux_amd64]
23 #mkdir /data/consul
24 
25 [root@zlm1 10:27:44 /vagrant/consul_1.2.2_linux_amd64]
26 #cp consul ~
27 
28 [root@zlm1 10:29:58 ~]
29 #cd /usr/local/bin
30 
31 [root@zlm1 10:30:02 /usr/local/bin]
32 #ls -l|grep consul
33 lrwxrwxrwx 1 root root      12 Aug 16 10:29 consul -> /root/consul
34 
35 [root@zlm1 10:32:08 /usr/local/bin]
36 #consul --help
37 Usage: consul [--version] [--help] <command> [<args>]
38 
39 Available commands are:
40     agent          Runs a Consul agent
41     catalog        Interact with the catalog
42     connect        Interact with Consul Connect
43     event          Fire a new event
44     exec           Executes a command on Consul nodes
45     force-leave    Forces a member of the cluster to enter the "left" state
46     info           Provides debugging information for operators.
47     intention      Interact with Connect service intentions
48     join           Tell Consul agent to join cluster
49     keygen         Generates a new encryption key
50     keyring        Manages gossip layer encryption keys
51     kv             Interact with the key-value store
52     leave          Gracefully leaves the Consul cluster and shuts down
53     lock           Execute a command holding a lock
54     maint          Controls node or service maintenance mode
55     members        Lists the members of a Consul cluster
56     monitor        Stream logs from a Consul agent
57     operator       Provides cluster-level tools for Consul operators
58     reload         Triggers the agent to reload configuration files
59     rtt            Estimates network round trip time between nodes
60     snapshot       Saves, restores and inspects snapshots of Consul server state
61     validate       Validate config files/directories
62     version        Prints the Consul version
63     watch          Watch for changes in Consul
def url(endpoint):
  return 'https://%s:%s/v1%s' % (config['host'], config['port'], endpoint)

def dump(response):
  print json.dumps(json.loads(response.text), indent=2)

AUTH = (config['user'], config['pass'])

 

 
Commands and Arguments

**Start agent of consul by “dev”
mode.**

The overall script architecture will be quite simple. A single function
per endpoint we’re exposing, a map to name it, and very simple command
line argument handling.

 1 [root@zlm1 10:40:43 /usr/local/bin]
 2 #consul agent -dev
 3 ==> Starting Consul agent...
 4 ==> Consul agent running!
 5            Version: 'v1.2.2'
 6            Node ID: '7c839914-8a47-ab36-8920-1a9da54fc6c3'
 7          Node name: 'zlm1'
 8         Datacenter: 'dc1' (Segment: '<all>')
 9             Server: true (Bootstrap: false)
10        Client Addr: [127.0.0.1] (HTTP: 8500, HTTPS: -1, DNS: 8600)
11       Cluster Addr: 127.0.0.1 (LAN: 8301, WAN: 8302)
12            Encrypt: Gossip: false, TLS-Outgoing: false, TLS-Incoming: false
13 
14 ==> Log data will now stream in as it occurs:
15 
16     2018/08/16 10:47:41 [DEBUG] agent: Using random ID "7c839914-8a47-ab36-8920-1a9da54fc6c3" as node ID
17     2018/08/16 10:47:41 [INFO] raft: Initial configuration (index=1): [{Suffrage:Voter ID:7c839914-8a47-ab36-8920-1a9da54fc6c3 Address:127.0.0.1:8300}]
18     2018/08/16 10:47:41 [INFO] serf: EventMemberJoin: zlm1.dc1 127.0.0.1
19     2018/08/16 10:47:41 [INFO] serf: EventMemberJoin: zlm1 127.0.0.1
20     2018/08/16 10:47:41 [INFO] raft: Node at 127.0.0.1:8300 [Follower] entering Follower state (Leader: "")
21     2018/08/16 10:47:41 [INFO] consul: Adding LAN server zlm1 (Addr: tcp/127.0.0.1:8300) (DC: dc1)
22     2018/08/16 10:47:41 [INFO] consul: Handled member-join event for server "zlm1.dc1" in area "wan"
23     2018/08/16 10:47:41 [DEBUG] agent/proxy: managed Connect proxy manager started
24     2018/08/16 10:47:41 [WARN] agent/proxy: running as root, will not start managed proxies
25     2018/08/16 10:47:41 [INFO] agent: Started DNS server 127.0.0.1:8600 (tcp)
26     2018/08/16 10:47:41 [INFO] agent: Started DNS server 127.0.0.1:8600 (udp)
27     2018/08/16 10:47:41 [INFO] agent: Started HTTP server on 127.0.0.1:8500 (tcp)
28     2018/08/16 10:47:41 [INFO] agent: started state syncer
29     2018/08/16 10:47:41 [WARN] raft: Heartbeat timeout from "" reached, starting election
30     2018/08/16 10:47:41 [INFO] raft: Node at 127.0.0.1:8300 [Candidate] entering Candidate state in term 2
31     2018/08/16 10:47:41 [DEBUG] raft: Votes needed: 1
32     2018/08/16 10:47:41 [DEBUG] raft: Vote granted from 7c839914-8a47-ab36-8920-1a9da54fc6c3 in term 2. Tally: 1
33     2018/08/16 10:47:41 [INFO] raft: Election won. Tally: 1
34     2018/08/16 10:47:41 [INFO] raft: Node at 127.0.0.1:8300 [Leader] entering Leader state
35     2018/08/16 10:47:41 [INFO] consul: cluster leadership acquired
36     2018/08/16 10:47:41 [INFO] consul: New leader elected: zlm1
37     2018/08/16 10:47:41 [INFO] connect: initialized CA with provider "consul"
38     2018/08/16 10:47:41 [DEBUG] consul: Skipping self join check for "zlm1" since the cluster is too small
39     2018/08/16 10:47:41 [INFO] consul: member 'zlm1' joined, marking health alive
40     2018/08/16 10:47:41 [DEBUG] agent: Skipping remote check "serfHealth" since it is managed automatically
41     2018/08/16 10:47:41 [INFO] agent: Synced node info
42     2018/08/16 10:47:44 [DEBUG] agent: Skipping remote check "serfHealth" since it is managed automatically
43     2018/08/16 10:47:44 [DEBUG] agent: Node info in sync
44     2018/08/16 10:47:44 [DEBUG] agent: Node info in sync
45     2018/08/16 10:48:41 [DEBUG] consul: Skipping self join check for "zlm1" since the cluster is too small
46     2018/08/16 10:49:13 [DEBUG] agent: Skipping remote check "serfHealth" since it is managed automatically
47     2018/08/16 10:49:13 [DEBUG] agent: Node info in sync
48     2018/08/16 10:49:41 [DEBUG] manager: Rebalanced 1 servers, next active server is zlm1.dc1 (Addr: tcp/127.0.0.1:8300) (DC: dc1)
49     2018/08/16 10:49:41 [DEBUG] consul: Skipping self join check for "zlm1" since the cluster is too small
50     2018/08/16 10:50:41 [DEBUG] consul: Skipping self join check for "zlm1" since the cluster is too small
51     2018/08/16 10:51:06 [DEBUG] agent: Skipping remote check "serfHealth" since it is managed automatically
52     2018/08/16 10:51:06 [DEBUG] agent: Node info in sync
53     
54 //Now the consul cluser has only one node "zlm1".
55 
56 [root@zlm1 11:11:17 ~]
57 #consul members
58 Node  Address         Status  Type    Build  Protocol  DC   Segment
59 zlm1  127.0.0.1:8301  alive   server  1.2.2  2         dc1  <all>
60 
61 //Type "Ctrl+C" can exit consul gracefully.
62 ^C    2018/08/16 11:24:50 [INFO] agent: Caught signal:  interrupt
63     2018/08/16 11:24:50 [INFO] agent: Graceful shutdown disabled. Exiting
64     2018/08/16 11:24:50 [INFO] agent: Requesting shutdown
65     2018/08/16 11:24:50 [WARN] agent: dev mode disabled persistence, killing all proxies since we can't recover them
66     2018/08/16 11:24:50 [DEBUG] agent/proxy: Stopping managed Connect proxy manager
67     2018/08/16 11:24:50 [INFO] consul: shutting down server
68     2018/08/16 11:24:50 [WARN] serf: Shutdown without a Leave
69     2018/08/16 11:24:50 [WARN] serf: Shutdown without a Leave
70     2018/08/16 11:24:50 [INFO] manager: shutting down
71     2018/08/16 11:24:50 [INFO] agent: consul server down
72     2018/08/16 11:24:50 [INFO] agent: shutdown complete
73     2018/08/16 11:24:50 [INFO] agent: Stopping DNS server 127.0.0.1:8600 (tcp)
74     2018/08/16 11:24:50 [INFO] agent: Stopping DNS server 127.0.0.1:8600 (udp)
75     2018/08/16 11:24:50 [INFO] agent: Stopping HTTP server 127.0.0.1:8500 (tcp)
76     2018/08/16 11:24:50 [INFO] agent: Waiting for endpoints to shut down
77     2018/08/16 11:24:50 [INFO] agent: Endpoints down
78     2018/08/16 11:24:50 [INFO] agent: Exit code: 1
79 
80 [root@zlm1 11:24:50 /usr/local/bin]
81 #ps aux|grep consul
82 root      4245  0.0  0.0 112640   960 pts/0    R+   11:24   0:00 grep --color=auto consul
83 
84 [root@zlm1 11:24:59 /usr/local/bin]
85 #consul members
86 Error retrieving members: Get http://127.0.0.1:8500/v1/agent/members?segment=_all: dial tcp 127.0.0.1:8500: connect: connection refused

Note that a real library would want a number of things that have been
omitted for brevity, such as argument checking and specific error
messages.

 

def version():
  return requests.get(url('/version'), auth=AUTH)

commands = {
  'version': version
}

cmd_name = sys.argv[1]
cmd_args = sys.argv[2:]
cmd = commands.get(cmd_name)
resp = cmd(*cmd_args)
dump(resp)

We can now run the version command.
$ python akiban_rest.py version
[
  {
    "server_version": "1.6.1-SNAPSHOT.2606",
    "server_name": "Akiban Server"
  }
]

Prepare the
server configuration file and start it again.

 
GET and POST

 1 [root@zlm1 11:38:35 /etc/consul.d]
 2 #cat server.json 
 3 {
 4     "data_dir":"/data/consul",
 5     "datacenter":"dc1",
 6     "log_level":"INFO",
 7     "server":true,
 8     "bootstrap_expect":1,
 9     "bind_addr":"192.168.56.100",
10     "client_addr":"192.168.56.100",
11     "ports":{
12     },
13     "ui":true,
14     "retry_join":[],
15     "retry_interval":"3s",
16     "raft_protocol":3,
17     "rejoin_after_leave":true
18 }
19 
20 [root@zlm1 11:38:39 /etc/consul.d]
21 #consul agent --config-dir=/etc/consul.d/ > /data/consul/consul.log 2>&1 &
22 [1] 4320
23 
24 [root@zlm1 11:39:02 /etc/consul.d]
25 #ps aux|grep consul
26 root      4320  1.3  2.0  54388 21252 pts/0    Sl   11:39   0:00 consul agent --config-dir=/etc/consul.d/
27 root      4333  0.0  0.0 112640   960 pts/0    R+   11:39   0:00 grep --color=auto consul
28 
29 [root@zlm1 11:39:08 /etc/consul.d]
30 #tail -f /data/consul/consul.log 
31     2018/08/16 11:39:02 [INFO] agent: Started HTTP server on 192.168.56.100:8500 (tcp)
32     2018/08/16 11:39:02 [INFO] agent: started state syncer
33     2018/08/16 11:39:07 [WARN] raft: Heartbeat timeout from "" reached, starting election
34     2018/08/16 11:39:07 [INFO] raft: Node at 192.168.56.100:8300 [Candidate] entering Candidate state in term 2
35     2018/08/16 11:39:07 [INFO] raft: Election won. Tally: 1
36     2018/08/16 11:39:07 [INFO] raft: Node at 192.168.56.100:8300 [Leader] entering Leader state
37     2018/08/16 11:39:07 [INFO] consul: cluster leadership acquired
38     2018/08/16 11:39:07 [INFO] consul: New leader elected: zlm1
39     2018/08/16 11:39:07 [INFO] consul: member 'zlm1' joined, marking health alive
40     2018/08/16 11:39:07 [INFO] agent: Synced node info
41     
42 [root@zlm1 11:51:38 ~]
43 #consul members
44 Error retrieving members: Get http://127.0.0.1:8500/v1/agent/members?segment=_all: dial tcp 127.0.0.1:8500: connect: connection refused
45 
46 [root@zlm1 11:51:44 ~]
47 #consul members --http-addr=192.168.56.100:8500
48 Node  Address              Status  Type    Build  Protocol  DC   Segment
49 zlm1  192.168.56.100:8301  alive   server  1.2.2  2         dc1  <all>

Now we can begin interacting with our hopes entity. New methods for
retrieving all, or specific, instances with GET and creating a new
instance with POST.

 

def entity_get_all(entity):
  return requests.get(url('/entity/%s' % entity), auth=AUTH)

def entity_get(entity, ids):
  return requests.get(url('/entity/%s/%s' % (entity, ids)), auth=AUTH)

def entity_post(entity, json):
  return requests.post(url('/entity/%s' % entity), data=json, auth=AUTH)

commands = {
  'version': version,
  'all': entity_get_all,
  'get': entity_get,
  'create': entity_post
}

Add a
client on zlm2.

The create, get, and get_all commands now function.

 1 [root@zlm1 13:33:57 /etc/consul.d]
 2 #scp /root/consul zlm2:~
 3 consul                                                                                                             100%   80MB  40.3MB/s   00:02
 4 
 5 [root@zlm2 13:35:33 ~]
 6 #mkdir /etc/consul.d
 7 
 8 [root@zlm2 13:36:37 ~]
 9 #mkdir /data/consul
10 
11 [root@zlm2 13:37:11 ~]
12 #cd /etc/consul.d/
13 
14 [root@zlm2 13:37:46 /etc/consul.d]
15 #ls -l
16 total 4
17 -rw-r--r-- 1 root root 241 Aug 16 13:35 client.json
18 
19 [root@zlm2 13:37:47 /etc/consul.d]
20 #cat client.json 
21 {
22     "data_dir": "/data/consul",
23     "enable_script_checks": true,
24     "bind_addr": "192.168.56.101",
25     "retry_join": ["192.168.56.100"],
26     "retry_interval": "30s",
27     "rejoin_after_leave": true,
28     "start_join": ["192.168.56.100"]
29 }
30 
31 [root@zlm2 13:43:42 /etc/consul.d]
32 #consul agent -client 192.168.56.101 -bind 192.168.56.101 --config-dir=/etc/consul.d
33 ==> Starting Consul agent...
34 ==> Joining cluster...
35     Join completed. Synced with 1 initial agents
36 ==> Consul agent running!
37            Version: 'v1.2.2'
38            Node ID: 'a69eae21-4e31-7edf-1f1a-3ec285a8fb3b'
39          Node name: 'zlm2'
40         Datacenter: 'dc1' (Segment: '')
41             Server: false (Bootstrap: false)
42        Client Addr: [192.168.56.101] (HTTP: 8500, HTTPS: -1, DNS: 8600)
43       Cluster Addr: 192.168.56.101 (LAN: 8301, WAN: 8302)
44            Encrypt: Gossip: false, TLS-Outgoing: false, TLS-Incoming: false
45 
46 ==> Log data will now stream in as it occurs:
47 
48     2018/08/16 13:43:48 [INFO] serf: EventMemberJoin: zlm2 192.168.56.101
49     2018/08/16 13:43:48 [INFO] agent: Started DNS server 192.168.56.101:8600 (udp)
50     2018/08/16 13:43:48 [WARN] agent/proxy: running as root, will not start managed proxies
51     2018/08/16 13:43:48 [INFO] agent: Started DNS server 192.168.56.101:8600 (tcp)
52     2018/08/16 13:43:48 [INFO] agent: Started HTTP server on 192.168.56.101:8500 (tcp)
53     2018/08/16 13:43:48 [INFO] agent: (LAN) joining: [192.168.56.100]
54     2018/08/16 13:43:48 [INFO] agent: Retry join LAN is supported for: aliyun aws azure digitalocean gce os packet scaleway softlayer triton vsphere
55     2018/08/16 13:43:48 [INFO] agent: Joining LAN cluster...
56     2018/08/16 13:43:48 [INFO] agent: (LAN) joining: [192.168.56.100]
57     2018/08/16 13:43:48 [INFO] serf: EventMemberJoin: zlm1 192.168.56.100
58     2018/08/16 13:43:48 [INFO] agent: (LAN) joined: 1 Err: <nil>
59     2018/08/16 13:43:48 [INFO] agent: started state syncer
60     2018/08/16 13:43:48 [INFO] consul: adding server zlm1 (Addr: tcp/192.168.56.100:8300) (DC: dc1)
61     2018/08/16 13:43:48 [INFO] agent: (LAN) joined: 1 Err: <nil>
62     2018/08/16 13:43:48 [INFO] agent: Join LAN completed. Synced with 1 initial agents
63     2018/08/16 13:43:48 [INFO] agent: Synced node info
64     
65 [root@zlm2 13:45:36 /etc/consul.d]
66 #consul members --http-addr=192.168.56.100:8500
67 Node  Address              Status  Type    Build  Protocol  DC   Segment
68 zlm1  192.168.56.100:8301  alive   server  1.2.2  2         dc1  <all>
69 zlm2  192.168.56.101:8301  alive   client  1.2.2  2         dc1  <default>
$ python akiban_rest.py create hopes '{"desc": "Part IV: A New Hope", "date": "2013-04-04 16:58:30", "bumpcount": 0}'
{
  "id": 1
}
$ python akiban_rest.py create hopes '{"desc": "Another", "date": "2013-04-04 16:58:35", "bumpcount": 0}'
{
  "id": 2
}
$ python akiban_rest.py get hopes 1
[
  {
    "date": "2013-04-04 16:58:30",
    "bumpcount": 0,
    "id": 1,
    "desc": "Part IV: A New Hope"
  }
]
$ python akiban_rest.py all hopes
[
  {
    "date": "2013-04-04 16:58:30",
    "bumpcount": 0,
    "id": 1,
    "desc": "Part IV: A New Hope"
  },
  {
    "date": "2013-04-04 16:58:35",
    "bumpcount": 0,
    "id": 2,
    "desc": "Another"
  }
]

 

 
PUT and DELETE

**Add two services on node
zlm2.**

We can now finish out the entity endpoint by adding commands for
replacing and deleting. Note that the dump has been tweaked to handle
no_content responses, like delete.

 1 [root@zlm2 13:58:37 /etc/consul.d]
 2 #cat service_master_check.json
 3 {
 4     "service":
 5        {
 6             "name": "w_db3306",
 7             "tags":  [
 8                           "Master Satus Check"
 9                         ],
10             "address": "192.168.56.100",
11             "port": 3306,
12             "check":    
13                             {
14                                 "args": [
15                                              "/data/consul/script/CheckMaster.py",
16                                              "3306"
17                                             ],
18                                 "interval": "15s"
19                             }
20         }
21 }
22 
23 [root@zlm2 13:59:42 /etc/consul.d]
24 #cat service_slave_check.json
25 {
26     "service":
27         {
28             "name": "r_db3306",
29             "tags": [
30                          "Slave Satus Check"
31                         ],
32             "address": "192.168.56.101",
33             "port": 3306,
34             "check":    
35                             {
36                                 "args": [
37                                              "/data/consul/script/CheckSlave.py",
38                                              "3306"
39                                             ],
40                                 "interval": "15s"
41                             }
42         }
43 }
44 
45 [root@zlm2 14:02:53 /etc/consul.d]
46 #ls -l
47 total 12
48 -rw-r--r-- 1 root root 241 Aug 16 13:35 client.json
49 -rw-r--r-- 1 root root 593 Aug 16 13:56 service_master_check.json
50 -rw-r--r-- 1 root root 590 Aug 16 13:57 servi_slave_check.json
def dump(response):
  if response.status_code != requests.codes.no_content:
    print json.dumps(json.loads(response.text), indent=2)

def entity_put(entity, ids, json):
  return requests.put(url('/entity/%s/%s' % (entity, ids)), data=json, auth=AUTH)

def entity_delete(entity, ids):
  return requests.delete(url('/entity/%s/%s' % (entity, ids)), auth=AUTH)

commands = {
  'version': version,
  'all': entity_get_all,
  'get': entity_get,
  'create': entity_post,
  'replace': entity_put,
  'delete': entity_delete
}

 

 

**Check CheckMaster.py
script.**

And to demonstrate.

 1 [root@zlm2 14:05:13 /data/consul/script]
 2 #cat CheckMaster.py 
 3 #!/usr/bin/python
 4 import sys
 5 import os
 6 import pymysql
 7 
 8 port = int(sys.argv[1])
 9 var={}
10 conn = pymysql.connect(host='192.168.56.100',port=port,user='zlm',passwd='zlmzlm')
11 #cur = conn.cursor(pymysql.cursor.DictCursor)
12 cur = conn.cursor()
13 
14 cur.execute("show global variables like \"%read_only%\"")
15 rows = cur.fetchall()
16 
17 for r in rows:
18     var[r[0]]=r[1]
19 if var['read_only']=='OFF' and var['super_read_only']=='OFF':
20         print "MySQL %d master instance." % port
21 else:
22         print "This is read only instance."
23         sys.exit(2)
24 
25 sys.exit(0)
26 cur.close()
27 conn.close()
$ python akiban_rest.py replace hopes 2 '{"id": 2, "desc": "A better name", "date": "2013-04-04 16:58:35", "bumpcount": 100}'
{
  "id": 2
}
$ python akiban_rest.py delete hopes 1
$ python akiban_rest.py all hopes
[
  {
    "date": "2013-04-04 16:58:35",
    "bumpcount": 100,
    "id": 2,
    "desc": "A better name"
  }
]

 

 
Summary

**Check CheckSlave.py
script.**

We started out with an empty DataSpace and a blank akiban_rest.py file.
After loading our example hope and deploying it, we could start to
interact with it through a simple REST call. Fifty lines of Python later
and we now have a respectable command line script for viewing, creating,
updating, and deleting our entities.

 1 [root@zlm2 14:07:11 /data/consul/script]
 2 #cat CheckSlave.py 
 3 #!/usr/bin/python
 4 import sys
 5 import os
 6 import pymysql
 7 
 8 port = int(sys.argv[1])
 9 var={}
10 conn = pymysql.connect(host='192.168.56.101',port=port,user='zlm',passwd='zlmzlm')
11 cur = conn.cursor
12 cur.execute("show global variables like \"%read_only%\"")
13 rows = cur.fetchall()
14 
15 for r in rows:
16     var[r[0]]=r[1]
17 if var['read_only']=='OFF' and var['super_read_only']=='OFF':
18         print "MySQL %d master instance." % port
19         sys.exit(2)
20 else:
21         print "MySQL %d is read only instance." % port
22 
23 cur = conn.cursor(pymysql.cursors.DictCursor)
24 cur.execute("show slave status")
25 slave_status = cur.fetchone()
26 
27 if len(slave_status)<30:
28         print "Slave replication setup error.";
29         sys.exit(2)
30 
31 if slave_status['Slave_IO_Running'] !='Yes' or slave_status['Slave_SQL_Running'] !='Yes':
32         print "Replication error: replication from host=%s, port=%s, io_thread=%s, sql_thread=%s, error info %s %s" % (slave_status['Master_Host'],slave_status['Master_Port'],slave_status['Slave_IO_Running'],slave_status['Slave_SQL_Running'],slave_status['Last_IO_Error'],slave_status['Last_SQL_Error'])
33         sys.exit(1)
34 print slave_status
35 
36 sys.exit(0)
37 cur.close()
38 conn.close()

All of the code from this post is available in this Gist. Who knows,
this might just grow into our Python client library!

 

android调用RESTful:http://bbs.it-home.org/thread-10447-1-1.html

**Restartt consul(or
reload).**

 

 1 [root@zlm2 14:12:37 /etc/consul.d]
 2 #consul members --http-addr=192.168.56.100:8500
 3 Node  Address              Status  Type    Build  Protocol  DC   Segment
 4 zlm1  192.168.56.100:8301  alive   server  1.2.2  2         dc1  <all>
 5 zlm2  192.168.56.101:8301  alive   client  1.2.2  2         dc1  <default>
 6 
 7 [root@zlm2 14:13:27 /etc/consul.d]
 8 #consul leave --http-addr=192.168.56.101:8500
 9 Graceful leave complete
10 
11 [root@zlm2 14:13:41 /etc/consul.d]
12 #consul members --http-addr=192.168.56.100:8500
13 Node  Address              Status  Type    Build  Protocol  DC   Segment
14 zlm1  192.168.56.100:8301  alive   server  1.2.2  2         dc1  <all>
15 zlm2  192.168.56.101:8301  left    client  1.2.2  2         dc1  <default>
16 
17 [root@zlm2 14:18:44 /etc/consul.d]
18 #consul agent --config-dir=/etc/consul.d/ -client 192.168.56.101 > /data/consul/consul.log 2>&1 &
19 [1] 5013
20 
21 [root@zlm2 14:19:59 /etc/consul.d]
22 #!ps
23 ps aux|grep consul
24 root      5013  2.3  2.0  56440 21132 pts/2    Sl   14:19   0:00 consul agent --config-dir=/etc/consul.d/ -client 192.168.56.101
25 root      5026  0.0  0.0 112640   960 pts/2    R+   14:19   0:00 grep --color=auto consul
26 
27 [root@zlm2 14:20:49 /etc/consul.d]
28 #consul reload -http-addr=192.168.56.101:8500
29 Configuration reload triggered

 

**Well,now we can login the
dashbord(GUI) of consul to check MySQL working
status.**

 

**图片 1**

 **图片 2**

 

**图片 3**