msgconnector, HATP's middleware
This page presents msgconnector's usage. msgconnector is responsible to carry messages form a module to another.
It is also responsible to the connection to other middlewares: OPRS, ORO, YARP.
![/!\](/moin_static1911/moniker/img/alert.png "/!\"){kind=small}
The way to install msgconnector is described in HATP/install.
1. Principle
msgconnector is composed of a server (MsgSever) that once started allows the different clients to connect. When a client connects it gives its name. This name is then used to carry a message from a client to another.
It is possible to declare several clients with the same name, then all the message are repeated to all the clients with the same name.
The message passed are using the JSON standard (see JSON).
Finally msgconnector can be connected to other middleware to extend the reach of HATP's messages. To do so bridges need to be started. So far the implemented bridge are:
- OPRS
- ORO
- YARP
- print (which is in fact just a backend to print all messages that it receives).
If you need an additionnal bridge put the request on the tracker, see the troubleshooting section at the bottom of this page.
2. Start the server
The default usage for the server is simply:
MsgServer
It starts the server on localhost and on the port 5500.
The help gives:
MsgServer --help
Usage: Default: MsgServer
Compact: MsgServer address:port [max_time]
Standard: MsgServer address port [max_time]
Complete: MsgServer [-a address] [-p port] [-t max_time] [-m max_connections]
Allowed options:
--help Produce help message
-a [ --address ] arg The address of the server (default : localhost)
-p [ --port ] arg The port number of the server (default : 5500)
-t [ --time ] arg The maximum inactivity time in second before the
automatic-shutdown of the server (default : 3600)
-m [ --max-clients ] arg Maximum number of clients that can connect at the
same time (default : 10)It is indeed possible to change the following parameters:
adrress, port on which the server starts
time which is how long the server will wait after the last message before automatically quitting
max_clients which is the number of clients that can be connected at the same time.
To connect the MsgServer over the network the address should be ":<port>" or nothing to connect over the network, not localhost.
3. Use a bridge
3.1. Use OPRS bridge
msgconnector-OPRS-bridge <NAME_OF_HATP> <NAME_OF_MSG_CLIENT> <MSGC_SERV> <NAME_OF_OPRS> <OPRS_SERV> <VERBOSE_MODE>
The parameters are:
<NAME_OF_HATP>: Registered name of hatponboard, usually "HATP".
<NAME_OF_MSG_CLIENT>: Name of this bridge on OPRS's side.
<MSGC_SERV>: The address of msgconnector's server, usually "localhost".*
<NAME_OF_OPRS>: Name of this bridge on HATP's side, should be the name of the OPRS module you want to talk to.
<OPRS_SERV>: The address of OPRS's server.*
<VERBOSE_MODE>: Can be 0 or 1 to toggle the verbose mode (all message processed are printed out).
*: The address can be a hostname like localhost.
3.2. Use ORO bridge
msgconnector-ORO-bridge <NAME_OF_BRIDGE> <MSGC_SERV> <ORO_SERV> <VERBOSE_MODE>
The parameters are:
<NAME_OF_BRIDGE>: The name of this bridge on HATP's side.
<MSGC_SERV>: The address of msgconnector's server, usually "localhost".
<ORO_SERV>: The address of ORO's server.
<VERBOSE_MODE>: Can be 0 or 1 to toggle the verbose mode (all message processed are printed out).
3.3. Use YARP bridge
msgconnector-YARP-bridge <NAME_OF_MSGC> <MSGC_SERV> <NAME_OF_YARPIN> <NAME_OF_YARPOUT> <VERBOSE_MODE>
The parameters are:
<NAME_OF_MSGC>: Name of the HATP's module that will be the target of the bridge messages.
<MSGC_SERV>: The address of msgconnector's server, usually "localhost".
<NAME_OR_YARPIN>: The name of this bridge on HATP's side.
<NAME_OR_YARPOUT>: The name of this bridge on YARP's side.
<VERBOSE_MODE>: Can be 0 or 1 to toggle the verbose mode (all message processed are printed out).
3.4. Use the print bridge
msgconnector-PRINT-bridge <NAME_OF_BRIDGE> <MSGC_SERV>
The parameters are:
<NAME_OF_MSGC>: Name of this bridge.
<MSGC_SERV>: The address of msgconnector's server, usually "localhost".
4. Changelog
4.1. Version 2.0.0
- Use libhatp to parse solution plan instead of doing it manually
- Fix automatic exit after an inactivity time
- Message max size in now 96Ko
- Add the tool HATPGoalTester that allow to send a request from command line
- Fix install/uninstall proccesses
Change the name of the repository and the project to msgconnector
- Add "package" target
4.2. Version 2.1.0
- Add install rules for the bridges
4.3. Version 2.2.0
- Improve packaging system
- Fix missing includes (due to update of the compiler)
4.4. Version 2.3.0
Change from epoll to select (allow to compile on NetBSD, ...)
4.5. Version 2.4.0
- Fix compilation in NstBSD
- Change the isConnected test (change in the API behaviour)
- Better error detection in both server and client
- Install Findmsgconnector to help CMake find it
4.6. Version 2.5.0
- Change parameters parsing for the server
4.7. Version 2.6.0
- Update OpenPRS bridge to allow to request the database for the initial state
4.8. Version 2.7.0
- Allow to request the whole OpenPRS database at once
4.9. Version 2.8.0
- Fix the binary installation (and RPATH management)
4.10. Version 2.8.1
- Correct the socket-error detection
4.11. Version 2.8.2
- Allow to start the server without a time limit
4.12. Version 2.8.3
- Add the possibility to send broadcast messages
- Client no longer automatically connect to localhost, possible to specify the server
4.13. Version 2.8.4
Server now binds to all addresses: allow to use msgconnector over network
- Socket is now blocking
5. License, Troubleshooting and Maintainer
HATP is distributed under 2-clause BSD license. (See here for details.)
The page to report problems or for pull request: Openrobots/msgconnector.
Current maintainer(s):
Raphaël Lallement: raphael.lallement [at] laas.fr, Website.