摘要：網(wǎng)頁刪除想要刪除隊列中的消息，是可以通過的網(wǎng)頁來操作的。但是這種方式存在一個問題，就是當(dāng)消息多的時候點(diǎn)擊，頁面會卡死。在節(jié)點(diǎn)恢復(fù)正常之前，持久化隊列將不可用。所以這次我想要先清除指定隊列的消息即可。網(wǎng)上搜了一下版本的消息。

在公司最新的項(xiàng)目上，由我們技術(shù)總監(jiān)搭了一套框架，其中有使用RabbitMq來監(jiān)聽監(jiān)聽寫事件，這也是我第一次使用RabbitMq。因?yàn)樵陂_發(fā)的過程中，有些事件會因?yàn)榇a的不完善消費(fèi)失敗，然后就會一直消費(fèi)，然后一直報錯。當(dāng)bug修復(fù)，把正確的代碼上傳到開發(fā)環(huán)境，原先遺留的問題消息任然存在，并且會阻塞隊列，讓之后的正常的消息無法讓系統(tǒng)正常的消費(fèi)。

想要刪除隊列中的消息，是可以通過RabbitMq的網(wǎng)頁來操作的。登錄上RabbitMQ Management之后,在 Queues 中打開指定的隊列：

然后在下方的 Delete / purge 中點(diǎn)擊 Delete 或者是 purge 都可以達(dá)到效果。

但是這種方式存在一個問題，就是當(dāng)消息多的時候點(diǎn)擊，頁面會卡死。即使沒有卡死也會出現(xiàn)如下對話框：

大概意思是找不到這個持久隊列，主節(jié)點(diǎn)已經(jīng)關(guān)閉或者是無法訪問。

現(xiàn)在只是小白階段，然后有點(diǎn)搞不懂，網(wǎng)上也沒有搜索到什么有用的答案。只找到一句話，來自：https://blog.csdn.net/u011973...

如果隊列的主節(jié)點(diǎn)不可用，則非鏡像隊列的行為取決于其持久性。在節(jié)點(diǎn)恢復(fù)正常之前，持久化隊列將不可用。在集群中其他節(jié)點(diǎn)上對主節(jié)點(diǎn)不可用的持久化隊列進(jìn)行任何操作都將失敗

沒有深究

然后我就去網(wǎng)上百度了一下，如何使用命令操作，然后找到了下面的解決方法：

rabbitmqctl stop_app
rabbitmqctl reset
rabbitmqctl start_app

執(zhí)行了一次之后確實(shí)是有效的。重啟的RabbitMq，然后里面的消息也確實(shí)清空了。

然后我當(dāng)上述的情況再次發(fā)生，需要清空消息，這樣個時候我不想用這樣一看就很粗暴的方式來操作，而且這種方式不僅會清空消息，還會清空所有配置信息。所以這次我想要先清除指定隊列的消息即可。

然后我找到了這個方法：

sudo rabbitmqctl purge_queue ${queue_name}
或
rabbitmqctl purge_queue ${queue_name}
或
rabbitmqctl -p ${vhostpath} purge_queue ${queue_name}

執(zhí)行報錯，說是找不到這個命令，給出的信息如下：

Error: could not recognise command
Usage:
rabbitmqctl [-n ] [-q]  [] 

Options:
    -n node
    -q

Default node is "rabbit@server", where server is the local host. On a host 
named "server.example.com", the node name of the RabbitMQ Erlang node will 
usually be rabbit@server (unless RABBITMQ_NODENAME has been set to some 
non-default value at broker startup time). The output of hostname -s is usually 
the correct suffix to use after the "@" sign. See rabbitmq-server(1) for 
details of configuring the RabbitMQ broker.

Quiet output mode is selected with the "-q" flag. Informational messages are 
suppressed when quiet mode is in effect.

Commands:
    stop []
    stop_app
    start_app
    wait 
    reset
    force_reset
    rotate_logs 

    join_cluster  [--ram]
    cluster_status
    change_cluster_node_type disc | ram
    forget_cluster_node [--offline]
    update_cluster_nodes clusternode
    sync_queue queue
    cancel_sync_queue queue
    set_cluster_name name

    add_user  
    delete_user 
    change_password  
    clear_password 
    set_user_tags   ...
    list_users

    add_vhost 
    delete_vhost 
    list_vhosts [ ...]
    set_permissions [-p ]    
    clear_permissions [-p ] 
    list_permissions [-p ]
    list_user_permissions 

    set_parameter [-p ]   
    clear_parameter [-p ]  
    list_parameters [-p ]

    set_policy [-p ] [--priority ] [--apply-to ] 
   
    clear_policy [-p ] 
    list_policies [-p ]

    list_queues [-p ] [ ...]
    list_exchanges [-p ] [ ...]
    list_bindings [-p ] [ ...]
    list_connections [ ...]
    list_channels [ ...]
    list_consumers [-p ]
    status
    environment
    report
    eval 

    close_connection  
    trace_on [-p ]
    trace_off [-p ]
    set_vm_memory_high_watermark 

 must be a member of the list [name, tracing].

The list_queues, list_exchanges and list_bindings commands accept an optional 
virtual host parameter for which to display results. The default value is "/".

 must be a member of the list [name, durable, auto_delete, 
arguments, policy, pid, owner_pid, exclusive_consumer_pid, 
exclusive_consumer_tag, messages_ready, messages_unacknowledged, messages, 
consumers, consumer_utilisation, memory, slave_pids, synchronised_slave_pids, 
status].

 must be a member of the list [name, type, durable, 
auto_delete, internal, arguments, policy].

 must be a member of the list [source_name, source_kind, 
destination_name, destination_kind, routing_key, arguments].

 must be a member of the list [pid, name, port, host, 
peer_port, peer_host, ssl, ssl_protocol, ssl_key_exchange, ssl_cipher, 
ssl_hash, peer_cert_subject, peer_cert_issuer, peer_cert_validity, state, 
channels, protocol, auth_mechanism, user, vhost, timeout, frame_max, 
channel_max, client_properties, recv_oct, recv_cnt, send_oct, send_cnt, 
send_pend].

 must be a member of the list [pid, connection, name, number, 
user, vhost, transactional, confirm, consumer_count, messages_unacknowledged, 
messages_uncommitted, acks_uncommitted, messages_unconfirmed, prefetch_count, 
global_prefetch_count].

實(shí)際上使用 rabbitmqctl -help 就能得到這些內(nèi)容。

可以看的出來，這里面已經(jīng) rabbitmqctl 所支持的命令都列了出來。其中并沒有 purge_queue 這個命令。不知道是不是版本問題還是怎么回事。

然后在這里找到了 rabbitmqadmin 這個東西。官網(wǎng)地址：https://www.rabbitmq.com/mana... 。在上面看到了這么一行文字

Alternatively, you can download the version of rabbitmqadmin which corresponds with the management plugin version 3.7.17 from GitHub.

打開GitHub的鏈接：https://raw.githubusercontent.com/rabbitmq/rabbitmq-management/v3.7.17/bin/rabbitmqadmin 里面好像是 rabbitmqadmin 的代碼?？戳艘幌侣窂剑瑅3.7.17。這個應(yīng)該是要對應(yīng)自己版本的。

rabbitmqctl status

查看版本：

[root@iZuf635fwy8k6ubk6r9yonZ ~]# rabbitmqctl status
Status of node rabbit@iZuf635fwy8k6ubk6r9yonZ ...
[{pid,3261},
 {running_applications,
     [{rabbitmq_management,"RabbitMQ Management Console","3.3.5"},
      {rabbitmq_web_dispatch,"RabbitMQ Web Dispatcher","3.3.5"},
      {webmachine,"webmachine","1.10.3-rmq3.3.5-gite9359c7"},
      {mochiweb,"MochiMedia Web Server","2.7.0-rmq3.3.5-git680dba8"},
      {rabbitmq_management_agent,"RabbitMQ Management Agent","3.3.5"},
      {rabbit,"RabbitMQ","3.3.5"},
      {mnesia,"MNESIA  CXC 138 12","4.11"},
      {os_mon,"CPO  CXC 138 46","2.2.14"},
      {amqp_client,"RabbitMQ AMQP Client","3.3.5"},
      {inets,"INETS  CXC 138 49","5.9.8"},
      {xmerl,"XML parser","1.3.6"},
      {sasl,"SASL  CXC 138 11","2.3.4"},
      {stdlib,"ERTS  CXC 138 10","1.19.4"},
      {kernel,"ERTS  CXC 138 10","2.16.4"}]},
 {os,{unix,linux}},
 {erlang_version,
     "Erlang R16B03-1 (erts-5.10.4) [source] [64-bit] [async-threads:30] [hipe] [kernel-poll:true]
"},
 {memory,
     [{total,44920360},
      {connection_procs,944512},
      {queue_procs,911352},
      {plugins,406328},
      {other_proc,13412192},
      {mnesia,200144},
      {mgmt_db,391944},
      {msg_index,95648},
      {other_ets,1174432},
      {binary,2676288},
      {code,20229484},
      {atom,711569},
      {other_system,3766467}]},
 {alarms,[]},
 {listeners,[{clustering,25672,"::"},{amqp,5672,"::"}]},
 {vm_memory_high_watermark,0.4},
 {vm_memory_limit,1654662758},
 {disk_free_limit,50000000},
 {disk_free,16424939520},
 {file_descriptors,
     [{total_limit,924},{total_used,9},{sockets_limit,829},{sockets_used,2}]},
 {processes,[{limit,1048576},{used,396}]},
 {run_queue,0},
 {uptime,3716267}]
...done.

結(jié)果發(fā)現(xiàn)自己的版本竟然是3.3.5。修改路徑https://raw.githubusercontent.com/rabbitmq/rabbitmq-management/v3.7.17/bin/rabbitmqadmin 為https://raw.githubusercontent.com/rabbitmq/rabbitmq-management/v3.3.5/bin/rabbitmqadmin，訪問，顯示并沒有這個頁面。大概是版本太老了。網(wǎng)上搜了一下3.3.5版本的消息。發(fā)現(xiàn)這個版本大概是2014年左右的東西，時至今日已經(jīng)五年過去了，也太老了吧。

本文章一次沒有寫完，在我寫的過程中，項(xiàng)目提交給測試進(jìn)行部分測試，然后同事在test環(huán)境也安裝了一個RabbitMq。我登上去看了一下，嗯，是有 purge_queue 這個命令的?？戳艘幌聇est的版本，3.6.8。果然還是版本問題。我之前一直操作的是dev服務(wù)器的東西，雖然本地也有安裝但是在本地進(jìn)行簡單的時候還是很好處理的，注釋掉代碼，然后重新運(yùn)行，消費(fèi)掉垃圾消息即可。

至于 rabbitmqadmin ，官網(wǎng)上有這么一段話：

Obtaining rabbitmqadmin
With the management plugin installed, browse to http://{hostname}:15672/cli/rabbitmqadmin to download. The tool supports

大概意思就可以通過訪問 http://{hostname}:15672/cli/rabbitmqadmin 來下載 rabbitmqadmin 。沒有深入研究。到此為止，后續(xù)可能會更新相關(guān)內(nèi)容。

發(fā)布文章的時候發(fā)現(xiàn)，過長的思否對過長的url省略的后面的部分，就像是這樣：https://raw.githubusercontent...
。所以在上面就對url稍微處理了一下。