vnx.opc_ua.Proxy¶
Module¶
The vnx.opc_ua.Proxy module provides a OPC-UA proxy to connect to a OPC-UA server.
It allows to call methods as well as read variables on the server.
Options¶
-
string
address
¶ OPC-UA server url to connect to, for example
opc.tcp://127.0.0.1:4840
.
-
bool
block_until_connect
= true¶ If to block client requests until first sucessful connect.
-
bool
block_until_reconnect
= false¶ If to block client requests until next sucessful reconnect, in case connection breaks down.
Functions¶
UA node ids are provided via a pair<ushort, Variant>
, where the first value is the namespace index
and the second value either an integer or a string.
In case a UA method returns more than one value the Variant
return value
will contain an array of variants, ie. vector<Variant>
. See also vnx.Variant.
-
Variant
call
(string method, vector<Variant> args) const¶ Calls a global
method
with the given arguments and returns the result. The implicit object for this call is UA_NS0ID_OBJECTSFOLDER.
-
Variant
object_call
(pair<ushort, Variant> object, string method, vector<Variant> args) const¶ Calls a
method
on theobject
with the given arguments and returns the result.
-
Variant
read_variable
(pair<ushort, Variant> node) const¶ Reads the value of a given variable
node
.
-
Variant
read_object_variable
(pair<ushort, Variant> object, string variable) const¶ Reads the value of a given
variable
of theobject
.
-
void
browse_all
()¶ Finds all available objects and variables on the server. Will be done automatically on every connect and re-connect.