• Get Usage
• Monitor Usage
• Client Library
  • Methods
  • Events
  • Options

Submit one or more parameters of name "pv" to the epics2web/caget URL. The response is a JSON object of the form:

Success:

{data: [{name: <name>, value: <value>},...]}

Failure:

{error: <error-reason>}

Note: You can optionally provide a parameter named "n" (the value can be anything) and it will be treated like "caget -n", which results in enum type PVs returning the numeric value instead of the string label.

var options = {},
    monitoredPvs = ['mypvname1', 'mypvname2'],
    con = new jlab.epics2web.ClientConnection(options);

con.onopen = function (e) {
    console.log('Socket Connected');
    con.monitorPvs(monitoredPvs);
};

con.onupdate = function (e) {
    console.log('Update');
    console.log('PV Name: ' + e.detail.pv);
    console.log('Date: ' + e.detail.date);
    console.log('PV Value: ' + e.detail.value);
};

con.oninfo = function (e) {
    console.log('Info');
    console.log('PV Name: ' + e.detail.pv);
    console.log('Connected: ' + e.detail.connected);
    console.log('PV Type: ' + e.detail.datatype);
     
    if (typeof e.detail['enum-labels'] !== 'undefined') {
        console.log('Enum Labels: ' + e.detail['enum-labels']);
    }    
};

jlab.epics2web.ClientConnection(options)
Create a new ClientConnection.
Input: options - see Options
Output: ClientConnection

jlab.epics2web.ClientConnection.monitorPvs(pvs)
Monitor a set of PVs.
Input: pvs - array of pv names

jlab.epics2web.ClientConnection.clearPvs(pvs)
Stop monitoring a set of PVs.
Input: pvs - array of pv names

jlab.epics2web.ClientConnection.ping()
Ping the server.

jlab.epics2web.ClientConnection.open()
Open the websocket connection.

jlab.epics2web.ClientConnection.close()
Close the websocket connection.

jlab.epics2web.ClientConnection.addEventListener(name, function)
Add a callback function on a named event.
Input: name - the event name; see Events
Input: function - the function to call

jlab.epics2web.ClientConnection.onopen(function)
Convenience function for open event. If more than one callback is needed use ClientConnection.addEventListener instead.
Input: function - the function to call

jlab.epics2web.ClientConnection.onclose(function)
Convenience function for close event. If more than one callback is needed use ClientConnection.addEventListener instead.
Input: function - the function to call

jlab.epics2web.ClientConnection.onconnecting(function)
Convenience function for connecting event. If more than one callback is needed use ClientConnection.addEventListener instead.
Input: function - the function to call

jlab.epics2web.ClientConnection.onclosing(function)
Convenience function for closing event. If more than one callback is needed use ClientConnection.addEventListener instead.
Input: function - the function to call

jlab.epics2web.ClientConnection.onerror(function)
Convenience function for error event. If more than one callback is needed use ClientConnection.addEventListener instead.
Input: function - the function to call

jlab.epics2web.ClientConnection.onupdate(function)
Convenience function for update event. If more than one callback is needed use ClientConnection.addEventListener instead.
Input: function - the function to call

jlab.epics2web.ClientConnection.oninfo(function)
Convenience function for info event. If more than one callback is needed use ClientConnection.addEventListener instead.
Input: function - the function to call

jlab.epics2web.ClientConnection.onpong(function)
Convenience function for pong event. If more than one callback is needed use ClientConnection.addEventListener instead.
Input: function - the function to call

• open - This event is triggered after the socket is open
• close - This event is triggered after the socket is closed
• connecting - This event is triggered as the socket is connecting
• closing - This event is triggered as the socket is closing
• error - This event is triggered upon socket error
• message - This event is triggered upon message (update/info/pong)
  • Param: event.type - One of 'update', 'info', 'pong'
  • Param: event.* - Contents based on type, see info, update, pong events
• info - This event is triggered upon an info message
  • Param: event.detail.pv - PV name
  • Param: event.detail.connected - true if an EPICS monitor was created
  • Param: event.detail.datatype - one of Datatypes
  • Param: event.detail['enum-labels'] - Array of enum labels or undefined if not of type DBR_ENUM
• update - This event is triggered upon an update message
  • Param: event.detail.pv - PV name
  • Param: event.detail.value - the updated value
  • Param: event.detail.date - the update date
• pong - This event is triggered upon a pong message

• DBR_DOUBLE (64-bit)
• DBR_FLOAT (32-bit)
• DBR_INT (32-bit - EPICS DBR_LONG)
• DBR_SHORT (16-bit - EPICS DBR_INT/DBR_SHORT)
• DBR_BYTE (8-bit - EPICS DBR_CHAR)
• DBR_STRING
• DBR_ENUM (This is the only compound type: includes both the integer value and the String label)

Note: EPICS Compound types are not supported (DBR_STS, DBR_TIME, DBR_GR, and DBR_CTRL).