Revision as of 08:31, 9 September 2013

About

mhttpd.js contains javascript function wrappers for most MIDAS AJAX functions typically used for implementing interactive custom pages for MIDAS experiments.

AJAX is a set of web development techniques used to construct interactive web applications:

http://en.wikipedia.org/wiki/Ajax_(programming)

mhttpd.js is typically served by mhttpd from $MIDASSYS/resources/mhttpd.js

<html>
<head>
...
<script src='mhttpd.js'></script>
...
</head>
...
</html>

A mostly up to date copy of mhttpd.js is linked here:

An example for using all mhttpd.js functions is included in the MIDAS distribution under examples/javascript1:

MIDAS AJAX functions can be accessed directly without using mhttpd.js wrappers (i.e. using the JSON-P script-tag method)

AJAX - MIDAS AJAX functions

By default, MIDAS AJAX functions assume that the web page was loaded from mhttpd and use relative URLs to access AJAX functions of the same mhttpd. If the web page is loaded from some other source, or needs to talk to a different mhttpd, use the ODBSetURL() function to set the base URL of the target mhttpd. Such cross-site access is normally blocked by web browsers, but recent versions of mhttpd implement the "cross-origin resource sharing" http header to permit such access.

Functions

Helper functions:

function getMouseXY(e)
function XMLHttpRequestGeneric()
function ODBExtractRecord(record, key)
function ODBEdit(path)
function ODBFinishInlineEdit(...)
function ODBInlineEditKeydown(...)
function ODBInlineEdit(...)

ODB access functions:

function ODBSetURL(url_of_mhttpd) - set the URL of target mhttpd (if web page is loaded from different source)
function ODBSet(path, value, pwdname) - write into ODB
function ODBGet(path, format, defval, len, type) - read from ODB
function ODBMGet(paths, callback, formats) - read multiple ODB entries
function ODBGetRecord(path) - read from ODB
function ODBKey(path) - get the description of an ODB entry
function ODBCopy(path, format) - read an ODB subtree in ODB, XML or JSON format
function ODBMCopy(paths, callback, format) - read multiple ODB subtrees in ODB, XML or JSON format, asynchronously
function ODBMCreate(paths, types, callback) - create multiple ODB entries using db_create_key(path, type)
function ODBMDelete(paths, callback) - delete multiple ODB entries using db_delete_key(path)
function ODBMRename(paths, names, callback) - rename multiple ODB entries using db_rename_key(path, name)
function ODBMLink(paths, links, callback) - create symbolic links using db_create_link(link, path)
function ODBMReorder(paths, indices, callback) - reorder ODB entries using db_reorder_key(path, index)

MIDAS access functions:

function ODBRpc_rev0(name, rpc, args)
function ODBRpc_rev1(name, rpc, max_reply_length, args)
function ODBGetMsg(n) - get midas messages from midas.log
function ODBGenerateMsg(m) - write a midas message
function ODBGetAlarms() - get list of active alarms

Summary table

Summary of mhttpd.js functions
Function	XML	JSON	JSON-P	async	AJAX	URI encoding
ODBSet(path, value, pwdname)	no	no	no	no	cmd=jset	by caller, except for "value"
ODBGet(path, format, defval, len, type)	no	no	no	no	cmd=jget	by caller, except for "format"
ODBMGet(paths, callback, formats)	no	no	no	yes	cmd=jget	by caller, including "formats"
ODBGetRecord(path)	no	no	no	no	cmd=jget with "name=1"	by caller
ODBKey(path)	no	yes	no	no	cmd=jkey	by caller
ODBCopy(path, format)	yes	yes	yes	no	cmd=jcopy	by caller, except for "format"
ODBMCopy(paths, callback, format)	yes	yes	yes	yes	cmd=jcopy	internal
ODBMCreate(paths, types, callback)	no	yes	yes	yes	cmd=jcreate	internal
ODBMRename(paths, names, callback)	no	yes	yes	yes	cmd=jrename	internal
ODBMDelete(paths, callback)	no	yes	yes	yes	cmd=jdelete	internal
ODBMLink(paths, links, callback)	no	yes	yes	yes	cmd=jlink	internal
ODBMReorder(paths, indices, callback)	no	yes	yes	yes	cmd=jreorder	internal
ODBRpc_rev0(name, rpc, args)	no	no	no	no	cmd=jrpc_rev0
ODBRpc_rev1(name, rpc, max_reply_length, args)	no	no	no	no	cmd=jrpc_rev1
ODBRpc(...)	yes	yes	yes	yes	cmd=jrpc
ODBGetMsg(n)	no	no	no	no	cmd=jmsg	not needed
ODBGenerateMsg(m)	no	no	no	no	cmd=jgenmsg	by caller
ODBGetAlarms()	no	no	no	no	cmd=jalm	-

ODBSetURL

Prototype:

function ODBSetURL(url)

Arguments:

url - URL of mhttpd we want to talk to.]

Returns: nothing

Example:

ODBSetURL("http://localhost:8080/");

ODBSet

See: AJAX#jset

See: http://ladd00.triumf.ca/~daqweb/doc/midas-old/html/RC_mhttpd_custom_ODB_access.html#RC_mhttpd_custom_odbset

Prototype:

function ODBSet(path, value, pwdname)

Arguments:

path - ODB path, must be URI-encoded
value - value to write, must NOT be URI-encoded (encoding is done inside ODBSet())
pwdname - see AJAX#jset

Returns: nothing

Error handling: issues an alert() if there are errors.

BUG: may call alert() and require user interaction.

ODBGet

See: AJAX#jset

See: http://ladd00.triumf.ca/~daqweb/doc/midas-old/html/RC_mhttpd_custom_ODB_access.html#RC_mhttpd_custom_odbget

Prototype:

function ODBGet(path, format, defval, len, type)

Arguments:

path - ODB path to read, must be URI-encoded
format - sprintf format for the data, must NOT be URI-encoded
defval - if ODB path does not exist, it is created using AJAX#jset with this value, must be URI-encoded. Disable this by using "undefined"
len - data length for jset
type - data type for jset

BUG: read the BUG sections in AJAX#jget

ODBMGet

See: AJAX#jget

See: http://ladd00.triumf.ca/~daqweb/doc/midas-old/html/RC_mhttpd_custom_ODB_access.html#RC_mhttpd_custom_odbmget

Prototype:

function ODBMGet(paths, callback, formats)

Arguments:

paths - array of strings - ODB paths to read, must be URI-encoded
callback - name of javascript function for asynchronous callback
formats - array of strings - sprintf() format strings for each ODB path, see BUGS in AJAX#jget, must by URI-encoded

Valid ODB path targets are: simple variables and arrays (specified as "/eq/foo/var/array[*]").

ODBMGet for subdirectories does not work (AJAX jget returns correct data, but incorrectly decoded by ODBMGet() javascript code).

ODBMGet for arrays specified without "[*]" is unknown.

BUG: read the BUG sections in AJAX#jget

ODBGetRecord

See: AJAX#jget with parameter "name=1"

See: http://ladd00.triumf.ca/~daqweb/doc/midas-old/html/RC_mhttpd_custom_ODB_access.html#RC_mhttpd_custom_odbgetrecord

Prototype:

function ODBGetRecord(path)

Arguments:

path - ODB path to read, must be URI-encoded

Returns:

request.responseText
use "function ODBExtractRecord(record, key)" to extract ODB values from data retuned by ODBGetRecord().

Valid ODB path targets are: simple variables, array elements ("/eq/foo/var/array[0]"), arrays (specified as "/eq/foo/var/array[*]") and subdirectories ("/experiment")

Usage:

      var rec1 = ODBGetRecord(encodeURIComponent("/Equipment/RpcExample/Variables"));
      document.getElementById('foo').innerHTML = rec1;
      document.getElementById('bar').innerHTML = ODBExtractRecord(rec1, 'SLOW[2]');

BUG: read the BUG sections in AJAX#jget

ODBKey

See: AJAX#jkey

Prototype:

function ODBKey(path)

Arguments:

path - ODB path, must be URI-encoded

Returns: javascript object with data fields corresponding to the data fields of MIDAS KEY (midas.h):

{"name":"SLOW","type":"TID_DOUBLE","num_values":"3","item_size":"8","last_written":"1376633931"}

Usage:

var key = new ODBKey(encodeURIComponent("/Equipment/RpcExample/Variables/SLOW"));
document.getElementById('foo').innerHTML = "name: " + key.name + " type: " + key.type;

ODBCopy

See: AJAX#jcopy

Prototype:

function ODBCopy(path, format)

Arguments:

path - ODB path, must be URI-encoded
format - data format (same as "encoding"), must NOT be URI-encoded

Returns: request.responseText, use JSON.parse() to decode JSON data.

Usage:

var data_json = ODBCopy("/Equipment/RpcExample/Variables", "json");
var obj = JSON.parse(data_json);
document.getElementById('json_data0').innerHTML = obj.SLOW[0];

Return value:

{
  "SLOW/key" : { "type" : 10, "num_values" : 3, "last_written" : 1376634320 },
  "SLOW" : [ 2357, 1376634320, -8.6602540236010100e+01 ]
}

ODBMCopy

See: AJAX#jcopy

Prototype:

function ODBMCopy(paths, callback, encoding)

Arguments:

paths - array of strings - odb paths to read
callback - name of javascript function for asynchronous callback, or "undefined" for synchronous return
encoding - requested data encoding - ODB, XML or JSON, see AJAX#jcopy

Returns:

synchrounous: returns request.responseText, use JSON.parse() to decode JSON data
asynchronous: calls the callback function with a single argument set to request.responseText, use JSON.parse() to decode JSON data

Usage:

      var paths = [
      "/Equipment/deapvme01/Settings/EnableControl",
      "/Equipment/deapvme01/Settings/mainSwitch",
      "/Equipment/deapvme01/Readback/sysMainSwitch.0",
      "/Equipment/deapvme01/Variables",
      "/Equipment/deapvme02/Settings/EnableControl",
      "/Equipment/deapvme02/Settings/mainSwitch",
      "/Equipment/deapvme02/Readback/sysMainSwitch.0",
      "/Equipment/deapvme02/Variables",
      "/Equipment/deapvme03/Settings/EnableControl",
      "/Equipment/deapvme03/Settings/mainSwitch",
      "/Equipment/deapvme03/Readback/sysMainSwitch.0",
      "/Equipment/deapvme03/Variables",
      ];

      ODBMCopy(paths, load_callback, "json");
...
      function load_callback(data)
      {
      var obj = JSON.parse(data);
      document.getElementById('enableControl1').innerHTML = obj[0].EnableControl;
      document.getElementById('mainSwitch1').innerHTML = obj[1]['mainSwitch'] + " / " + obj[2]['sysMainSwitch.0'];
      document.getElementById('p5v1').innerHTML = obj[3].current[0];
...

JSON data returned from ODBMCopy():

[ { "EnableControl/key" : { "type" : 7, "last_written" : 1375145722 }, "EnableControl" : 1 } , { "mainSwitch/key" : { "type" : 7, "last_written" : 1376610870 }, "mainSwitch" : 1 } , { "sysMainSwitch.0/key" : { "type" : 7, "last_written" : 1376681747 }, "sysMainSwitch.0" : 1 } , { "switch/key" : { "type" : 7, "num_values" : 3, "last_written" : 1376681747 }, "switch" : [ 1, 1, 1 ], "status/key" : { "type" : 7, "num_values" : 3, "last_written" : 1376681747 }, "status" : [ 1, 1, 1 ], "demandVoltage/key" : { "type" : 9, "num_values" : 3, "last_written" : 1376681747 }, "demandVoltage" : [ 5, 12, 12 ], "senseVoltage/key" : { "type" : 9, "num_values" : 3, "last_written" : 1376681747 }, "senseVoltage" : [ 5.0500002e+00, 1.1980000e+01, 1.1990000e+01 ], "current/key" : { "type" : 9, "num_values" : 3, "last_written" : 1376681747 }, "current" : [ 9.0229996e+01, 4.2700000e+00, 5.9899998e+00 ], "sparkCount/key" : { "type" : 7, "num_values" : 3, "last_written" : 1376681747 }, "sparkCount" : [ 0, 0, 0 ], "sensorTemperature/key" : { "type" : 7, "num_values" : 8, "last_written" : 1376681747 }, "sensorTemperature" : [ -128, -128, 25, -128, -128, 25, -128, -128 ], "fanSpeed/key" : { "type" : 7, "num_values" : 3, "last_written" : 1376681747 }, "fanSpeed" : [ 3180, 3112, 3236 ] } , { "EnableControl/key" : { "type" : 7, "last_written" : 1375145722 }, "EnableControl" : 1 } , { "mainSwitch/key" : { "type" : 7, "last_written" : 1376603253 }, "mainSwitch" : 1 } , { "sysMainSwitch.0/key" : { "type" : 7, "last_written" : 1376681750 }, "sysMainSwitch.0" : 1 } , { "switch/key" : { "type" : 7, "num_values" : 3, "last_written" : 1376681750 }, "switch" : [ 1, 1, 1 ], "status/key" : { "type" : 7, "num_values" : 3, "last_written" : 1376681750 }, "status" : [ 1, 1, 1 ], "demandVoltage/key" : { "type" : 9, "num_values" : 3, "last_written" : 1376681750 }, "demandVoltage" : [ 5, 12, 12 ], "senseVoltage/key" : { "type" : 9, "num_values" : 3, "last_written" : 1376681750 }, "senseVoltage" : [ 5, 1.1950000e+01, 1.1980000e+01 ], "current/key" : { "type" : 9, "num_values" : 3, "last_written" : 1376681750 }, "current" : [ 1.4169999e+01, 1.1000000e+00, 8.0000001e-01 ], "sparkCount/key" : { "type" : 7, "num_values" : 3, "last_written" : 1376681750 }, "sparkCount" : [ 0, 0, 0 ], "sensorTemperature/key" : { "type" : 7, "num_values" : 8, "last_written" : 1376681750 }, "sensorTemperature" : [ -128, -128, -128, -128, -128, -128, -128, 22 ], "fanSpeed/key" : { "type" : 7, "num_values" : 3, "last_written" : 1376681750 }, "fanSpeed" : [ 3217, 3225, 3213 ] } , { "EnableControl/key" : { "type" : 7, "last_written" : 1375145722 }, "EnableControl" : 1 } , { "mainSwitch/key" : { "type" : 7, "last_written" : 1376596430 }, "mainSwitch" : 1 } , { "sysMainSwitch.0/key" : { "type" : 7, "last_written" : 1376681752 }, "sysMainSwitch.0" : 1 } , { "switch/key" : { "type" : 7, "num_values" : 3, "last_written" : 1376681752 }, "switch" : [ 1, 1, 1 ], "status/key" : { "type" : 7, "num_values" : 3, "last_written" : 1376681752 }, "status" : [ 1, 1, 1 ], "demandVoltage/key" : { "type" : 9, "num_values" : 3, "last_written" : 1376681752 }, "demandVoltage" : [ 5, 12, 12 ], "senseVoltage/key" : { "type" : 9, "num_values" : 3, "last_written" : 1376681752 }, "senseVoltage" : [ 4.9800000e+00, 1.2009999e+01, 1.1969999e+01 ], "current/key" : { "type" : 9, "num_values" : 3, "last_written" : 1376681752 }, "current" : [ 9.1139999e+01, 4.1999998e+00, 6.0300002e+00 ], "sparkCount/key" : { "type" : 7, "num_values" : 3, "last_written" : 1376681752 }, "sparkCount" : [ 0, 0, 0 ], "sensorTemperature/key" : { "type" : 7, "num_values" : 8, "last_written" : 1376681752 }, "sensorTemperature" : [ -128, -128, 24, -128, -128, 27, -128, -128 ], "fanSpeed/key" : { "type" : 7, "num_values" : 3, "last_written" : 1376681752 }, "fanSpeed" : [ 3153, 3067, 3180 ] } ]

ODBGetMsg

See: AJAX#jmsg

Prototype:

function ODBGetMsg(n)

Arguments:

n - number of midas messages to return

Returns: array of strings, if n==1, as single string.

Usage:

var data = ODBGetMsg(10);
document.getElementById("foo").innerHTML = data.join("\n");

ODBGenerateMsg

See: AJAX#jgenmsg

Prototype:

function ODBGenerateMsg(m)

Arguments:

m - text written into midas messages, must be URI-encoded.

Usage:

ODBGenerateMsg(encodeURIComponent("message text"));

ODBGetAlarms

See: AJAX#jalm

Prototype:

function ODBGetAlarms()

Returns: array of strings

Usage:

var data = ODBGetAlarms();
document.getElementById("foo").innerHTML = data.join("\n");

Mhttpd.js: Difference between revisions

Revision as of 08:31, 9 September 2013

Contents

About

Functions

Summary table

ODBSetURL

ODBSet

ODBGet

ODBMGet

ODBGetRecord

ODBKey

ODBCopy

ODBMCopy

ODBGetMsg

ODBGenerateMsg

ODBGetAlarms

Navigation menu

Mhttpd.js: Difference between revisions

Revision as of 08:31, 9 September 2013

About

Functions

Summary table

ODBSetURL

ODBSet

ODBGet

ODBMGet

ODBGetRecord

ODBKey

ODBCopy

ODBMCopy

ODBGetMsg

ODBGenerateMsg

ODBGetAlarms

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