Client examples

Client

Connecting

Anonymous Connection

e.g.

`{ok, Client} = opcua_client:connect(<<"opc.tcp://localhost:4840">>).`
`{ok, Client} = opcua_client:connect(<<"opc.tcp://localhost:4840">>,
    #{auth => anonymous}).`

Connecting with Username and Password

e.g.

`{ok, Client} = opcua_client:connect(<<"opc.tcp://localhost:4840">>,
    #{auth => {user_name, <<"test">>, <<"test">>}}).`

Connecting with a specific Security mode and Policy

e.g.

`{ok, Client} = opcua_client:connect(<<"opc.tcp://localhost:4840">>,
   #{mode => sign_and_encrypt, policy =>basic256sha256}).`

Browsing Nodes

e.g.

`opcua_client:browse(Client, objects).`

With explicit namespace:

`opcua_client:browse(Client, {1, <<"PLC1">>}).`

Reading Attributes

e.g.

With explicit namespace:

`opcua_client:read(Client, {4, <<"OPCUA.int1">>}, value).`

Batch read:

`opcua_client:read(Client, {4, <<"OPCUA.int1">>}, [node_id, value]).`

With array index:

`opcua_client:read(Client, {4, <<"OPCUA.array1">>}, {value, 2}).`

With multidimensional array index:

`opcua_client:read(Client, {4, <<"OPCUA.array2">>}, {value, [1, 0, 3]}).`

Batch read with indexes:

`opcua_client:read(Client, {4, <<"OPCUA.array1">>}, [{value, 0}, {value, 5}]).`

With array range:

`opcua_client:read(Client, {4, <<"OPCUA.array2">>}, {value, {1,4}}).`
`opcua_client:read(Client, {4, <<"OPCUA.array2">>}, {value, [0,{0,3},{2,4}]}).`

With expanded arrays of structs (server dependent):

`opcua_client:read(Client, {4, <<"OPCUA.array3[1]">>}, value).`

Writing Attributes

e.g.

With explicit namespace:

`opcua_client:write(Client, {4, <<"OPCUA.int1">>}, value, {opcua_variant, int16, 42}).`

Full array write:

`opcua_client:write(Client, {4, <<"OPCUA.array1">>}, value, {opcua_variant, boolean, [false,true,false,true,false,true,false,true,false,true]}).`

With array index:

`opcua_client:write(Client, {4, <<"OPCUA.array1">>}, {value, 2}, true).`

With multidimensional array index:

`opcua_client:write(Client, {4, <<"OPCUA.array2">>}, {value, [1, 0, 3]}, false).`

With expanded arrays of structs (server dependent):

`opcua_client:write(Client, {4, <<"OPCUA.array3[1]">>}, {value, {opcua_variant, extension_object, {opcua_extension_object, {opcua_node_id, 4, string, <<"<StructuredDataType>:DataStruct_OpCon_MDT">>}, byte_string, #{chg_over_wpc_no => 0, date_time => 0, dest_cell => 0, dest_workpos => 0, error_no => 0, identifier => <<"foobar">>, origin_cell => 0, origin_workpos => 0, repeat_counter => 0, state => 0, stator_angel => 0, str_type_no => <<>>, w_p_c_no => 0, w_p_c_no_exter => 0, winding => 0}}}}).`