RPC Call

Synopsis

rsb call [OPTIONS] SERVER-URI/METHOD([ARGUMENT])

Description

Call METHOD of the RSB RPC server at SERVER-URI with argument ARGUMENT and print the result to standard output, if any.

SERVER-URI designates the root scope of the remote server and the transport that should be used.

Tip

For details regarding the URI syntax involved in transport and channel specifications, see URIs.

ARGUMENT is treated as follows:

  • If ARGUMENT is the empty string, i.e. the call specification is of the form SERVER-URI/METHOD(), the METHOD is called without argument.

  • As the respective Boolean value when equal to true or false

  • As string when surrounded with double-quotes (")

  • As integer number when consisting of digits without decimal point

  • As float number when consisting of digits with decimal point

  • If ARGUMENT starts with /, it is parsed as a scope.

  • If ARGUMENT is the single character - or the string -:binary, the entire “contents” of standard input (until end of file) is read as a string or octet-vector respectively and used as argument for the method call.

  • If ARGUMENT is of one of the forms #P"PATHNAME", #P"PATHNAME":ENCODING or #P"PATHNAME":binary, the file designated by PATHNAME is read into a string (optionally employing ENCODING) or octet-vector and used as argument for the method call.

  • If ARGUMENT is of the form pb:.MESSAGE-TYPE-NAME:{FIELDS}, a protocol buffer message of type MESSAGE-TYPE-NAME is constructed and its fields are populated according to FIELDS. FIELDS uses the syntax produced/consumed by the various TextFormat classes of the protocol buffer API and the --decode/--encode options of the protoc binary.

  • If ARGUMENT is of one of the forms

    • pb:.MESSAGE-TYPE-NAME:#P"PATHNAME"
    • pb:.MESSAGE-TYPE-NAME:#P"PATHNAME":ENCODING
    • pb:.MESSAGE-TYPE-NAME:-

    , a protocol buffer message of type MESSAGE-TYPE-NAME is constructed according to the contents of the file designated by PATHNAME or the input read from standard input respectively.

The definition of the data type specified in MESSAGE-TYPE-NAME can be loaded automatically using the common --on-demand-idl-loading option.

Note

When written as part of a shell command, some of the above forms may require protection from processing by the shell, usually by surrounding the form in single quotes (‘). For example:

$ rsb call 'socket:/foobar/()'            # empty argument
$ rsb call 'socket:/foo/bar(#P"my-file")' # read argument from my-file

The usual commandline options are accepted. Specialized commandline options:

--timeout SPEC, -t SPEC

If the result of the method call does not arrive within the amount of time specified by SPEC, consider the call to have failed and exit with non-zero status.

--no-wait

Do not wait for the result of the method call. Immediately return with zero status without printing a result to standard output.

Examples

  • $ rsb call 'spread:/mycomponent/control/status()'
    "running" # prints return value, if any
    $ rsb call 'spread:/mycomponent/control/terminate()'
    $ # returns once the method call completes
    

    In the above example, the call command is used to invoke the status and terminate methods of the remote server at scope /mycomponent/control without an argument.

  • $ cat my-data.txt | rsb call 'socket:/printer/print(-)'
    $ cat my-data.txt | rsb call 'socket:/printer/print(-:binary)'
    $ rsb call 'socket:/printer/print(#P"my-data.txt")'
    $ rsb call 'socket:/printer/print(#P"my-data.txt":latin-1)'
    $ rsb call 'socket:/printer/print(#P"my-data.txt":binary)'
    

    Two ways of using the content of the file my-data.txt as argument in a call of the print method on the scope /printer. The call uses the socket transport (with its default configuration). This form can only be used for sending string payloads.

    Note

    Note the use of single quotes (') to prevent elements of the pathname #P"my-data.txt" from being processed by the shell.

  • $ rsb call                                                  \
      -I…/rst-proto/proto/stable/                               \
      -l…/rst-proto/proto/stable/rst/robot/RobotCollision.proto \
      'socket:/mycomponent/handlecollision(pb:.rst.robot.RobotCollision:{kind: "SELF" collision_detail: { geometry: { contact_points: [ { x: 0 y: 1 z: 2 frame_id: "foo" }, { x: 3 y: 4 z: 5 } ] } object_1: "o1" } })'
    

    or

    $ rsb call                                                  \
      -I…/rst-proto/proto/stable/                               \
      --on-demand-idl-loading=blocking                          \
      'socket:/mycomponent/handlecollision(pb:.rst.robot.RobotCollision:{kind: "SELF" collision_detail: { geometry: { contact_points: [ { x: 0 y: 1 z: 2 frame_id: "foo" }, { x: 3 y: 4 z: 5 } ] } object_1: "o1" } })'
    

    In the above examples, the call tool is used to call the handlecollision method of the remote server at scope /mycomponent with a protocol buffer message argument. The protocol buffer message is of type rst.robot.RobotCollision with kind enum field set to SELF and an embedded rst.kinematics.ObjectCollision message with two contact points in the collision_detail field.

    The specification of the message content uses the syntax produced/consumed by the various TextFormat classes of the protocol buffer API and the --decode/--encode options of the protoc binary.

    Note

    Note how the definition of the protocol buffer message type is loaded either explicitly using the -l (--load-idl) commandline option or implicitly using the --on-demand-idl-loading commandline option. Both methods require specifying a search path using the -I (--idl-path) commandline option.

Implementations

Implementation Language Project Repository Link
Common Lisp rsb-tools-cl “0.14” branch of https://code.cor-lab.org/git/rsb.git.tools-cl