%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
***** ServerSentEvents *****

The only constantly open connection:

/updates

  response: <id-message> <update-message> <redraw-message> <console-update-message> <graph-update-message>

  the id-message is got immediately, later a mix of all other types of messages may be received

*********************************************************************************************************************************

<id-message> = {
  "type": "id",
  "id":<id>,
  "title": <title>
}

<update-message> = {
  "type": "update",
  "updates": [{"name": <name0>, "value": <value0>}, ...]
}

<redraw-message> = {
  "type": "redraw",
  "path": <path>
}

<console-update-message> = {
  "type": "command" | "reply",
  "origin": "self" | "other",
  "lines": <line>
}

<graph-update-message> = {
  "type": "graph-update",
  "time": <server-time>,
  "graph": {
      "<name1>": [[<time>,<value>],[<time>,<value>]...
      "<name2>": [[<time>,<value>],[<time>,<value>]...
      ...
  }
}

<graph-redraw-message> = {
  "type": "graph-redraw"
}

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
***** XMLHttp *****

All other connections are to be closed (getJSON):

*********************************************************************************************************************************
/getblock?path=<path>&id=<id>

  response: <draw-message>

<draw-message> = {
  "type": "draw",
  "path": <path>,
  "components": [<component0>, <component1>, ...]
}

*********************************************************************************************************************************

<component> = <input> | <rdonly> | <checkbox> | <radio-group> 

<input> = {
  "type": "input",
  "name": <variable name>,
  "title": <title>
  <optional-attributes>
}

<rdonly> = {
  "type": "rdonly",
  "name": <variable name>,
  "title": <title>
  <optional-attributes>
}

<checkbox> = {
  "type": "checkbox",
  "name": <variable name>,
  "title": <title>
  <optional-attributes>
}

<radio-group> = {
  "type": "radio",
  "name": <variable name>,
  "title": <title>,
  "buttons": [{"value": <value0>, "title": <title0>} , ...],
  <optional-attributes>
}

<optional-attributes> =
  ["info": <tool-tip-text> ,]


*********************************************************************************************************************************

/updateblock?path=<path>&id=<id>

  response: <accept-block-message>    (and from now on, update-messages (incl. initial updates) are sent)

<accept-block-message> = {
  "type": "accept-block",
}

*********************************************************************************************************************************

/sendcommand?command=<command>&id=<id>

  response: <accept-command-message>

<accept-command-message> = {
  "type": "accept-command",
}

*********************************************************************************************************************************
/gettime?time=<start>,<end>&id=<id>

  response: <time-message>

<time-message> = {
  "type":"time",
  "time": [<start>, <end>]
}

********************************************************************************************************************************* 

/getvars?time=<time>&id=<id>

  response: <varlist-message>

<varlist-message> = {
  "type":"var_list",
  "blocks": [
     {
      "tag":"K_2", 
      "unit": "K",
      "curves": [
        {
          "name":<name1>,
          "label":<label1>,
          "color":<color1>
        },
        {
          "name":<name2>,
          ...
        } ...
      ]
    },
    {
      "tag":"mbar",
      "unit": "mbar",
      "curves": ...
    },
    ...
  ]
}

********************************************************************************************************************************* 
 
/updategraph?id=<id>[&variables=<variable list>]

  if <variables list> is given, the given variables will be updated with the graph-update-message

  response: <accept-graph-message>

<accept-graph-message> =  = {
  "type": "accept-graph",
  "live": true/false
}

   the "live" flag is true when the last /graph query was including the actual time

********************************************************************************************************************************* 
 
/graph?time=<start>,<end>&variables=<variable list>&id=<id>

  the given variables are added to the list of variables being updated with the graph-update-message

  response: <graph-draw-message>

<graph-draw-message> =  = {
  "type": "graph-draw",
  "graph": {
      "<name1>": [[<time>,<value>],[<time>,<value>]...
      "<name2>": [[<time>,<value>],[<time>,<value>]...
      ...
  }

*********************************************************************************************************************************

/console?id=<id>

  response: <accept-console-message>   (and from now on, console-updates-messages (incl. history) are sent)

<accept-console-message> = {
  "type": "accept-console",
}