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Can you point out the mistake for me?

Services have a Request and a Reply type. SetJointStates is most likely a module containing both the Request and Reply types, but isn't a service request itself.

If you'd do a print (dir(SetJointStates)) we should be able to verify that.

In any case: you'll probably want to use the SetJointStatesRequest.

Can you point out the mistake for me?

Services have a Request and a Reply type. SetJointStates is most likely a module containing both the Request and Reply types, but isn't a service request itself.

If you'd do a print (dir(SetJointStates)) we should be able to verify that.

In any case: you'll probably want to use the SetJointStatesRequest.

Can you point out the mistake for me?

Services have a Request and a Reply type. SetJointStates is most likely a module containing both the Request and Reply types, but isn't a service request itself.

If you'd do a print (dir(SetJointStates)) we should be able to verify that.

In any case: you'll probably want to use the SetJointStatesRequest., or just use the ServiceProxy directly.

Another problem with the code is that you've named your ServiceProxy variable set_joint_states, while you already have a method called set_joint_states. That is not going to work.

[..]
from robotic_arm_algorithms.srv import SetJointStates

def set_joint_states(joint_states):
    rospy.wait_for_service('set_joint_states')
    try:
        set_joint_states = rospy.ServiceProxy('set_joint_states', SetJointStates)
        msg = SetJointStates()
        [..]

Can you point out the mistake for me?

Services have a Request and a Reply type. SetJointStates is most likely a module containing both the Request and Reply types, but isn't a service request itself.itself (note how the tutorial you link to imports *, not AddTwoInts).

If you'd do a print (dir(SetJointStates)) we should be able to verify that.

In any case: you'll probably want to use the SetJointStatesRequest, or just use the ServiceProxy directly.

Another problem with the code is that you've named your ServiceProxy variable set_joint_states, while you already have a method called set_joint_states. That is not going to work.

[..]
from robotic_arm_algorithms.srv import SetJointStates

def set_joint_states(joint_states):
    rospy.wait_for_service('set_joint_states')
    try:
        set_joint_states = rospy.ServiceProxy('set_joint_states', SetJointStates)
        msg = SetJointStates()
        [..]

Can you point out the mistake for me?

Services have a Request and a Reply type. SetJointStates is most likely a module containing both the Request and Reply types, but isn't a service request itself (note how the tutorial you link to imports *, not AddTwoInts).

If you'd do a print (dir(SetJointStates)) we should be able to verify that.

In any case: you'll probably want to use the SetJointStatesRequest, or just use the ServiceProxy directly.

Another problem with the code is that you've named your ServiceProxy variable set_joint_states, while you already have a method called set_joint_states. That is not going to work.

[..]
from robotic_arm_algorithms.srv import SetJointStates

def set_joint_states(joint_states):
    rospy.wait_for_service('set_joint_states')
    try:
        set_joint_states = rospy.ServiceProxy('set_joint_states', SetJointStates)
        msg = SetJointStates()
        [..]

Can you point out the mistake for me?

Services have a Request and a Reply type. SetJointStates is most likely a module containing both the Request and Reply types, but isn't a service request itself (note how the tutorial you link to imports *, not AddTwoInts).

If you'd do a print (dir(SetJointStates)) we should be able to verify that.

In any case: you'll probably want to use the SetJointStatesRequest, or just use the ServiceProxy directly.

Another problem with the code is that you've named your ServiceProxy variable set_joint_states, while you already have a method called set_joint_states. That is not going to work.

Edit:

When I put print (dir(SetJointStates)) into set_joint_states method of the client source code, following strings prints on terminal:

['__class__', '__delattr__', '__dict__', '__doc__', '__format__', '__getattribute__', '__hash__', '__init__', '__module__', '__new__', '__reduce__', '__reduce_ex__', '__repr__', '__setattr__', '__sizeof__', '__str__', '__subclasshook__', '__weakref__', '_md5sum', '_request_class', '_response_class', '_type']

As you see, there is a _request_class and a _response_class field present.

That would seem to confirm what I wrote above (ie: SetJointStates is not a request or a response class itself, but the composite one encapsulating both.

As I wrote in my earlier answer, you'll want to use the SetJointStatesRequest class instead. Be sure to import that.

[..]

from robotic_arm_algorithms.srv import SetJointStates, SetJointStatesRequest

def set_joint_states(joint_states):
    rospy.wait_for_service('set_joint_states')
    try:
        # bind our local service proxy
        svc_set_joint_states = rospy.ServiceProxy('set_joint_states', SetJointStates)

        # create the service request
        req = SetJointStatesRequest()

        # populate the fields of the request
        req.forearm_0 = joint_states[0]
        req.forearm_1 = joint_states[1]
        req.arm_0 = joint_states[2]
        req.arm_1 = joint_states[3]

        # invoke the service, passing it the request
        resp = scv_set_joint_states(req)

        # 'resp' is here of type 'SetJointStatesReponse'

        # perhaps do something with the response

    except rospy.ServiceException, e:
        print "Service call failed: %s"%e

[..]

[..]
from robotic_arm_algorithms.srv import SetJointStates

def set_joint_states(joint_states):
    rospy.wait_for_service('set_joint_states')
    try:
        set_joint_states = rospy.ServiceProxy('set_joint_states', SetJointStates)
        msg = SetJointStates()
        [..]

Can you point out the mistake for me?

Services have a Request and a ReplyResponse type. SetJointStates is most likely a module containing both the Request and ReplyResponse types, but isn't a service request or response itself (note how the tutorial you link to imports *, not AddTwoInts).

If you'd do a print (dir(SetJointStates)) we should be able to verify that.

In any case: you'll probably want to use the SetJointStatesRequest, or just use the ServiceProxy directly.

Another problem with the code is that you've named your ServiceProxy variable set_joint_states, while you already have a method called set_joint_states. That is not going to work.

Edit:

When I put print (dir(SetJointStates)) into set_joint_states method of the client source code, following strings prints on terminal:

['__class__', '__delattr__', '__dict__', '__doc__', '__format__', '__getattribute__', '__hash__', '__init__', '__module__', '__new__', '__reduce__', '__reduce_ex__', '__repr__', '__setattr__', '__sizeof__', '__str__', '__subclasshook__', '__weakref__', '_md5sum', '_request_class', '_response_class', '_type']

As you see, there is a _request_class and a _response_class field present.

That would seem to confirm what I wrote above (ie: SetJointStates is not a request or a response class itself, but the composite one encapsulating both.

As I wrote in my earlier answer, you'll want to use the SetJointStatesRequest class instead. Be sure to import that.

Edit 2: we should try to avoid duplicating these Q&As but I can't find one quickly, so here is an example of some code that will probably work:

[..]

from robotic_arm_algorithms.srv import SetJointStates, SetJointStatesRequest

def set_joint_states(joint_states):
    rospy.wait_for_service('set_joint_states')
    try:
        # bind our local service proxy
        svc_set_joint_states = rospy.ServiceProxy('set_joint_states', SetJointStates)

        # create the service request
        req = SetJointStatesRequest()

        # populate the fields of the request
        req.forearm_0 = joint_states[0]
        req.forearm_1 = joint_states[1]
        req.arm_0 = joint_states[2]
        req.arm_1 = joint_states[3]

        # invoke the service, passing it the request
        resp = scv_set_joint_states(req)

        # 'resp' is here of type 'SetJointStatesReponse'

        # perhaps do something with the response

    except rospy.ServiceException, e:
        print "Service call failed: %s"%e

[..]

[..]
from robotic_arm_algorithms.srv import SetJointStates

def set_joint_states(joint_states):
    rospy.wait_for_service('set_joint_states')
    try:
        set_joint_states = rospy.ServiceProxy('set_joint_states', SetJointStates)
        msg = SetJointStates()
        [..]

Can you point out the mistake for me?

Services have a Request and a Response type. SetJointStates is most likely a module containing both the Request and Response types, but isn't a service request or response itself (note how the tutorial you link to imports *, not AddTwoInts).

If you'd do a print (dir(SetJointStates)) we should be able to verify that.

In any case: you'll probably want to use the SetJointStatesRequest, or just use the ServiceProxy directly.

Another problem with the code is that you've named your ServiceProxy variable set_joint_states, while you already have a method called set_joint_states. That is not going to work.

Edit:

When I put print (dir(SetJointStates)) into set_joint_states method of the client source code, following strings prints on terminal:

['__class__', '__delattr__', '__dict__', '__doc__', '__format__', '__getattribute__', '__hash__', '__init__', '__module__', '__new__', '__reduce__', '__reduce_ex__', '__repr__', '__setattr__', '__sizeof__', '__str__', '__subclasshook__', '__weakref__', '_md5sum', '_request_class', '_response_class', '_type']

As you see, there is a _request_class and a _response_class field present.

That would seem to confirm what I wrote above (ie: SetJointStates is not a request or a response class itself, but the composite one encapsulating both.

As I wrote in my earlier answer, you'll want to use the SetJointStatesRequest class instead. Be sure to import that.

Edit 2: we should try to avoid duplicating these Q&As but I can't find one quickly, so here is an example of some code that will probably work:

[..]

from robotic_arm_algorithms.srv import SetJointStates, SetJointStatesRequest
*

def set_joint_states(joint_states):
    rospy.wait_for_service('set_joint_states')
    try:
        # bind our local service proxy
        svc_set_joint_states = rospy.ServiceProxy('set_joint_states', SetJointStates)

        # create the service request
        req = SetJointStatesRequest()

        # populate the fields of the request
        req.forearm_0 = joint_states[0]
        req.forearm_1 = joint_states[1]
        req.arm_0 = joint_states[2]
        req.arm_1 = joint_states[3]

        # invoke the service, passing it the request
        resp = scv_set_joint_states(req)

        # 'resp' is here of type 'SetJointStatesReponse'

        # perhaps do something with the response

    except rospy.ServiceException, e:
        print "Service call failed: %s"%e

[..]

Note that in addition to using the Request class, I've also renamed the service proxy variable to svc_set_joint_states to avoid shadowing your set_joint_states(..) method.