You are viewing a plain text version of this content. The canonical link for it is here.
Posted to users@qpid.apache.org by James Franco <mj...@gmail.com> on 2016/12/02 20:14:18 UTC
Sending messages to queues - is my understanding correct
I am trying to understand what happens when we send a message to a queue
with a little more perspective.
Supose I have an exchange called *my-ex *that has a queue called *my_q*
and this queue is bound to the exchange with the binding key *my_bid*.
Now when I send a message to the queue directrly like this
>> ./spout my_q/someSubject This is a bind test
The message is received when I do this
>> ./drain my_q
Now I have two questions regarding this:
1- since the address being used is my_q and there is no exchange mentioned
(or the exchnage is blank) in the address does the broker first check the
default exchange and then look consecutively into other exchanges until it
finds the specified queue ?
2-From my understanding so far is that when a message is sent to an
exchange instead of a queue then depending on the type of exchange the
message is routed to a specific queue based on the routing id and binding
id of the queue , however if the message is sent to the a queue directly
(instead of an exchnage name) then routing id and binding id do not matter
and the message will be delivered to the queue. Is my understanding correct
?
Re: Sending messages to queues - is my understanding correct
Posted by James Franco <mj...@gmail.com>.
Thanks for clearing that up in a nice way.
On Fri, Dec 2, 2016 at 8:31 PM, Gordon Sim <gs...@redhat.com> wrote:
> On 02/12/16 20:14, James Franco wrote:
>
>> I am trying to understand what happens when we send a message to a queue
>> with a little more perspective.
>>
>> Supose I have an exchange called *my-ex *that has a queue called *my_q*
>> and this queue is bound to the exchange with the binding key *my_bid*.
>> Now when I send a message to the queue directrly like this
>>
>> ./spout my_q/someSubject This is a bind test
>>>>
>>>
>> The message is received when I do this
>>
>> ./drain my_q
>>>>
>>>
>> Now I have two questions regarding this:
>>
>> 1- since the address being used is my_q and there is no exchange mentioned
>> (or the exchnage is blank) in the address does the broker first check the
>> default exchange and then look consecutively into other exchanges until
>> it
>> finds the specified queue ?
>>
>
> No. The client will send the message to the default exchange with a
> routing key of 'my_q'. If a queue named 'my_q' exists, the default exchange
> is guaranteed to have a binding with key 'my_q' for the my_q queue.
>
> 2-From my understanding so far is that when a message is sent to an
>> exchange instead of a queue then depending on the type of exchange the
>> message is routed to a specific queue based on the routing id and binding
>> id of the queue , however if the message is sent to the a queue directly
>> (instead of an exchnage name) then routing id and binding id do not matter
>> and the message will be delivered to the queue. Is my understanding
>> correct
>> ?
>>
>
> At the protocol level, messages are *always* sent to an exchange. The qpid
> messaging API presents a higher level abstraction where you just send to or
> receive from an address. If the address is a queue, and if you are using
> AMQP 0-10 (rather than 1.0), this will cause the client to send to the
> default exchange (which is really just a hack to allow you to emulate
> sending to a queue which that protocol version did not support).
>
>
> ---------------------------------------------------------------------
> To unsubscribe, e-mail: users-unsubscribe@qpid.apache.org
> For additional commands, e-mail: users-help@qpid.apache.org
>
>
Re: Sending messages to queues - is my understanding correct
Posted by Gordon Sim <gs...@redhat.com>.
On 02/12/16 20:14, James Franco wrote:
> I am trying to understand what happens when we send a message to a queue
> with a little more perspective.
>
> Supose I have an exchange called *my-ex *that has a queue called *my_q*
> and this queue is bound to the exchange with the binding key *my_bid*.
> Now when I send a message to the queue directrly like this
>
>>> ./spout my_q/someSubject This is a bind test
>
> The message is received when I do this
>
>>> ./drain my_q
>
> Now I have two questions regarding this:
>
> 1- since the address being used is my_q and there is no exchange mentioned
> (or the exchnage is blank) in the address does the broker first check the
> default exchange and then look consecutively into other exchanges until it
> finds the specified queue ?
No. The client will send the message to the default exchange with a
routing key of 'my_q'. If a queue named 'my_q' exists, the default
exchange is guaranteed to have a binding with key 'my_q' for the my_q queue.
> 2-From my understanding so far is that when a message is sent to an
> exchange instead of a queue then depending on the type of exchange the
> message is routed to a specific queue based on the routing id and binding
> id of the queue , however if the message is sent to the a queue directly
> (instead of an exchnage name) then routing id and binding id do not matter
> and the message will be delivered to the queue. Is my understanding correct
> ?
At the protocol level, messages are *always* sent to an exchange. The
qpid messaging API presents a higher level abstraction where you just
send to or receive from an address. If the address is a queue, and if
you are using AMQP 0-10 (rather than 1.0), this will cause the client to
send to the default exchange (which is really just a hack to allow you
to emulate sending to a queue which that protocol version did not support).
---------------------------------------------------------------------
To unsubscribe, e-mail: users-unsubscribe@qpid.apache.org
For additional commands, e-mail: users-help@qpid.apache.org