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Building Applications With Open MCT
Scope and purpose of this document
This document is intended to serve as a reference for developing an application based on Open MCT. It will provide details of the API functions necessary to extend the Open MCT platform meet common use cases such as integrating with a telemetry source.
The best place to start is with the Open MCT Tutorials. These will walk you through the process of getting up and running with Open MCT, as well as addressing some common developer use cases.
Building From Source
The latest version of Open MCT is available from our GitHub repository.
If you have git
, and node
installed, you can build Open MCT with the commands
git clone https://github.com/nasa/openmct.git
cd openmct
npm install
These commands will fetch the Open MCT source from our GitHub repository, and build
a minified version that can be included in your application. The output of the
build process is placed in a dist
folder under the openmct source directory,
which can be copied out to another location as needed. The contents of this
folder will include a minified javascript file named openmct.js
as well as
assets such as html, css, and images necessary for the UI.
Starting an Open MCT application
To start a minimally functional Open MCT application, it is necessary to include
the Open MCT distributable, enable some basic plugins, and bootstrap the application.
The tutorials walk through the process of getting Open MCT up and running from scratch,
but provided below is a minimal HTML template that includes Open MCT, installs
some basic plugins, and bootstraps the application. It assumes that Open MCT is
installed under an openmct
subdirectory, as described in Building From Source.
This approach includes openmct using a simple script tag, resulting in a global
variable named openmct
. This openmct
object is used subsequently to make API
calls.
Open MCT is packaged as a UMD (Universal Module Definition) module, so common script loaders are also supported.
<!DOCTYPE html>
<html>
<head>
<title>Open MCT</title>
<script src="openmct.js"></script>
</head>
<body>
<script>
openmct.setAssetPath('openmct/dist');
openmct.install(openmct.plugins.LocalStorage());
openmct.install(openmct.plugins.MyItems());
openmct.install(openmct.plugins.UTCTimeSystem());
openmct.install(openmct.plugins.Espresso());
openmct.start();
</script>
</body>
</html>
The Open MCT library included above requires certain assets such as html templates,
images, and css. If you installed Open MCT from GitHub as described in the section
on Building from Source then these assets will have been
downloaded along with the Open MCT javascript library. You can specify the
location of these assets by calling openmct.setAssetPath()
. Typically this will
be the same location as the openmct.js
library is included from.
There are some plugins bundled with the application that provide UI, persistence, and other default configuration which are necessary to be able to do anything with the application initially. Any of these plugins can, in principle, be replaced with a custom plugin. The included plugins are documented in the Included Plugins section.
Plugins
Defining and Installing a New Plugin
openmct.install(function install(openmctAPI) {
// Do things here
// ...
});
New plugins are installed in Open MCT by calling openmct.install
, and providing
a plugin installation function. This function will be invoked on application
startup with one parameter - the openmct API object. A common approach used in
the Open MCT codebase is to define a plugin as a function that returns this
installation function. This allows configuration to be specified when the plugin is included.
eg.
openmct.install(openmct.plugins.Elasticsearch("http://localhost:8002/openmct"));
This approach can be seen in all of the plugins provided with Open MCT.
Domain Objects and Identifiers
Domain Objects are the basic entities that represent domain knowledge in Open MCT. The temperature sensor on a solar panel, an overlay plot comparing the results of all temperature sensors, the command dictionary for a spacecraft, the individual commands in that dictionary, the "My Items" folder: All of these things are domain objects.
A Domain Object is simply a javascript object with some standard attributes.
An example of a Domain Object is the "My Items" object which is a folder in
which a user can persist any objects that they create. The My Items object
looks like this:
{
identifier: {
namespace: ""
key: "mine"
}
name:"My Items",
type:"folder",
location:"ROOT",
composition: []
}
Object Attributes
The main attributes to note are the identifier
, and type
attributes.
identifier
: A composite key that provides a universally unique identifier for this object. Thenamespace
andkey
are used to identify the object. Thekey
must be unique within the namespace.type
: All objects in Open MCT have a type. Types allow you to form an ontology of knowledge and provide an abstraction for grouping, visualizing, and interpreting data. Details on how to define a new object type are provided below.
Open MCT uses a number of builtin types. Typically you are going to want to define your own if extending Open MCT.
Domain Object Types
Custom types may be registered via the addType
function on the opencmt Type
registry.
eg.
openmct.types.addType('my-type', {
label: "My Type",
description: "This is a type that I added!",
creatable: true
});
The addType
function accepts two arguments:
- A
string
key identifying the type. This key is used when specifying a type for an object. - An object type specification. An object type definition supports the following
attributes
label
: astring
naming this object typedescription
: astring
specifying a longer-form description of this typeinitialize
: afunction
which initializes the model for new domain objects of this type. This can be used for setting default values on an object when it is instantiated.creatable
: Aboolean
indicating whether users should be allowed to create this type (default:false
). This will determine whether the type appears in theCreate
menu.cssClass
: Astring
specifying a CSS class to apply to each representation of this object. This is used for specifying an icon to appear next to each object of this type.
The Open MCT Tutorials provide a step-by-step examples of writing code for Open MCT that includes a section on defining a new object type.
Root Objects
In many cases, you'd like a certain object (or a certain hierarchy of objects) to be accessible from the top level of the application (the tree on the left-hand side of Open MCT.) For example, it is typical to expose a telemetry dictionary as a hierarchy of telemetry-providing domain objects in this fashion.
To do so, use the addRoot
method of the object API.
eg.
openmct.objects.addRoot({
namespace: "my-namespace",
key: "my-key"
});
The addRoot
function takes a single object identifier
as an argument.
Root objects are loaded just like any other objects, i.e. via an object provider.
Object Providers
An Object Provider is used to build Domain Objects, typically retrieved from some source such as a persistence store or telemetry dictionary. In order to integrate telemetry from a new source an object provider will need to be created that can build objects representing telemetry points exposed by the telemetry source. The API call to define a new object provider is fairly straightforward. Here's a very simple example:
openmct.objects.addProvider('example.namespace', {
get: function (identifier) {
return Promise.resolve({
identifier: identifier,
name: 'Example Object',
type: 'example-object-type'
});
}
});
The addProvider
function takes two arguments:
namespace
: Astring
representing the namespace that this object provider will provide objects for.provider
: Anobject
with a single function,get
. This function accepts an Identifier for the object to be provided. It is expected that theget
function will return a Promise that resolves with the object being requested.
In future, object providers will support other methods to enable other operations with persistence stores, such as creating, updating, and deleting objects.
Composition Providers
The composition of a domain object is the list of objects it contains, as shown (for example) in the tree for browsing. Open MCT provides a default solution for composition, but there may be cases where you want to provide the composition of a certain object (or type of object) dynamically.
Adding Composition Providers
You may want to populate a hierarchy under a custom root-level object based on the contents of a telemetry dictionary. To do this, you can add a new Composition Provider:
openmct.composition.addProvider({
appliesTo: function (domainObject) {
return domainObject.type === 'my-type';
},
load: function (domainObject) {
return Promise.resolve(myDomainObjects);
}
});
The addProvider
function accepts a Composition Provider object as its sole
argument. A Composition Provider is a javascript object exposing two functions:
appliesTo
: Afunction
that accepts adomainObject
argument, and returns aboolean
value indicating whether this composition provider applies to the given object.load
: Afunction
that accepts adomainObject
as an argument, and returns aPromise
that resolves with an array of Identifier. These identifiers will be used to fetch Domain Objects from an Object Provider
Default Composition Provider
The default composition provider applies to any domain object with a composition
property. The value of composition
should be an array of identifiers, e.g.:
var domainObject = {
name: "My Object",
type: 'folder',
composition: [
{
id: '412229c3-922c-444b-8624-736d85516247',
namespace: 'foo'
},
{
key: 'd6e0ce02-5b85-4e55-8006-a8a505b64c75',
namespace: 'foo'
}
]
};
Telemetry Providers
When connecting to a new telemetry source, you will need to register a new Telemetry Provider. A Telemetry Provider retrieves telemetry data from some telemetry source, and exposes them in a way that can be used by Open MCT. A telemetry provider typically can support a one off request for a batch of telemetry data, or it can provide the ability to subscribe to receive new telemetry data when it becomes available, or both.
openmct.telemetry.addProvider({
supportsRequest: function (domainObject) {
//...
},
supportsSubscribe: function (domainObject) {
//...
},
request: function (domainObject, options) {
//...
},
subscribe: function (domainObject, callback, options) {
//...
}
})
A telemetry provider is an object with the following functions defined:
supportsRequest
: An optionalfunction
that accepts a Domain Object and returns aboolean
value indicating whether or not this provider supports telemetry requests for the given object. If this returnstrue
then arequest
function must be defined.supportsSubscribe
: An optionalfunction
that accepts a Domain Object and returns aboolean
value indicating whether or not this provider supports telemetry subscriptions. If this returnstrue
then asubscribe
function must also be defined. As withrequest
, the return value will typically be conditional, and based on attributes ofdomainObject
such as its identifier.request
: Afunction
that returns aPromise
that will resolve with anArray
of telemetry in a single query. This function accepts as arguments a Domain Object and an object containing some request options.subscribe
: Afunction
that accepts a Domain Object, a callbackfunction
, and a telemetry request. The callback is invoked whenever telemetry is available, and
The implementations for request
and subscribe
can vary depending on the
nature of the endpoint which will provide telemetry. In the example above,
it is assumed that myAdapter
contains the implementation details
(such as HTTP requests, WebSocket connections, etc.) associated with some telemetry
source.
For a step-by-step guide to building a telemetry adapter, please see the Open MCT Tutorials.
Telemetry Requests
Telemetry requests support time bounded queries. A call to a Telemetry Provider's
request
function will include an options
argument. These are simply javascript
objects with attributes for the request parameters. An example of a telemetry
request object with a start and end time is included below:
{
start: 1487981997240,
end: 1487982897240
}
Telemetry Formats
Telemetry format objects define how to interpret and display telemetry data. They have a simple structure:
key
: Astring
that uniquely identifies this formatter.format
: Afunction
that takes a raw telemetry value, and returns a human-readablestring
representation of that value. It has one required argument, and three optional arguments that provide context and can be used for returning scaled representations of a value. An example of this is representing time values in a scale such as the time conductor scale. There are multiple ways of representing a point in time, and by providing a minimum scale value, maximum scale value, and a count, it's possible to provide more useful representations of time given the provided limitations.value
: The raw telemetry value in its native type.minValue
: An optional argument specifying the minimum displayed value.maxValue
: An optional argument specifying the maximum displayed value.count
: An optional argument specifying the number of displayed values.
parse
: Afunction
that takes astring
representation of a telemetry value, and returns the value in its native type. It accepts one argument:text
: Astring
representation of a telemetry value.
validate
: Afunction
that takes astring
representation of a telemetry value, and returns aboolean
value indicating whether the provided string can be parsed.
Registering Formats
Formats are registered with the Telemetry API using the addFormat
function. eg.
openmct.telemetry.addFormat({
key: 'number-to-string',
format: function (number) {
return number + '';
},
parse: function (text) {
return Number(text);
},
validate: function (text) {
return !isNaN(text);
}
});
Examples of Formats in Use
- The NumberFormat
provides an example of a simple format available by default in OpenMCT. - The UTCTimeFormat
is a more complex implementation of a format that uses the optional context
arguments in
format
to provide scale-appropriate values.
Telemetry Data
Telemetry data is provided to Open MCT by Telemetry Providers
in the form of javascript objects. A collection of telemetry values (for example,
retrieved in response to a request
) is represented by an Array
of javascript
objects. These telemetry javascript objects are simply key value pairs.
Typically a telemetry datum will have some timestamp associated with it. This
time stamp should have a key that corresponds to some time system supported by
Open MCT. If the UTCTimeSystem
plugin is installed, then the key utc
can be used.
An example of a telemetry provider request function that returns a collection of mock telemtry data is below:
openmct.telemetry.addProvider({
supportsRequest: function (domainObject) {
return true
},
request: function (domainObject, options) {
return Promise.resolve([
{
'utc': Date.now() - 2000,
'value': 1,
},
{
'utc': Date.now() - 1000,
'value': 2,
},
{
'utc': Date.now(),
'value': 3,
}
]);
}
})
Time API
Open MCT provides API for managing the temporal state of the application. Central to this is the concept of "time bounds". Views in Open MCT will typically show telemetry data for some prescribed date range, and the Time API provides a way to centrally manage these bounds.
The Time API exposes a number of methods for querying and setting the temporal state of the application, and emits events to inform listeners when the state changes.
Because the data displayed tends to be time domain data, Open MCT must always
have at least one time system installed and activated. When you download Open MCT,
it will be pre-configured to use the UTC time system, which is installed and
activated, along with other default plugins, in index.html
. Installing and
activating a time system is simple, and is covered
in the next section.
Time Systems and Bounds
Defining and Registering Time Systems
The time bounds of an Open MCT application are defined as numbers, and a Time System gives meaning and context to these numbers so that they can be correctly interpreted. Time Systems are javscript objects that provide some information about the current time reference frame. An example of defining and registering a new time system is given below:
openmct.time.addTimeSystem({
key: 'utc',
name: 'UTC Time',
cssClass = 'icon-clock',
timeFormat = 'utc',
durationFormat = 'duration',
isUTCBased = true
});
The example above defines a new utc based time system. In fact, this time system
is configured and activated by default from index.html
in the default
installation of Open MCT if you download the source from GitHub. Some details of
each of the required properties is provided below.
key
: Astring
that uniquely identifies this time system.name
: Astring
providing a brief human readable label. If the Time Conductor plugin is enabled, this name will identify the time system in a dropdown menu.cssClass
: A class namestring
that will be applied to the time system when it appears in the UI. This will be used to represent the time system with an icon. There are a number of built-in icon classes available in Open MCT, or a custom class can be used here.timeFormat
: Astring
corresponding to the key of a registered telemetry time format. The format will be used for displaying discrete timestamps from telemetry streams when this time system is activated. If the UTCTimeSystem is enabled, then theutc
format can be used if this is a utc-based time systemdurationFormat
: Astring
corresponding to the key of a registered telemetry time format. The format will be used for displaying time ranges, for example00:15:00
might be used to represent a time period of fifteen minutes. These are used by the Time Conductor plugin to specify relative time offsets. If the UTCTimeSystem is enabled, then theduration
format can be used if this is a utc-based time systemisUTCBased
: Aboolean
that defines whether this time system represents numbers in UTC terrestrial time.
Getting and Setting the Active Time System
Once registered, a time system can be activated using a key, or an instance of the time system itself.
openmct.time.timeSystem('utc');
A time system can be immediately activated upon registration:
var utcTimeSystem = {
key: 'utc',
name: 'UTC Time',
cssClass = 'icon-clock',
timeFormat = 'utc',
durationFormat = 'duration',
isUTCBased = true
};
openmct.time.addTimeSystem(utcTimeSystem);
openmct.time.timeSystem(utcTimeSystem);
Setting the active time system will trigger a time system event.
Time Bounds
The TimeAPI provides a getter/setter for querying and setting time bounds. Time
bounds are simply an object with a start
and an end end
attribute.
start
: Anumber
representing a moment in time in the active Time System. This will be used as the beginning of the time period displayed by time-responsive telemetry views.end
: Anumber
representing a moment in time in the active Time System. This will be used as the end of the time period displayed by time-responsive telemetry views.
If invoked with bounds, it will set the new time bounds system-wide. If invoked without any parameters, it will return the current application-wide time bounds.
const ONE_HOUR = 60 * 60 * 1000;
let now = Date.now();
openmct.time.bounds({start: now - ONE_HOUR, now);
To respond to bounds change events, simply register a callback against the bounds
event. For more information on the bounds event, please see the section on Time Events.
Clocks
The Time API can be set to follow a clock source which will cause the bounds to be updated automatically whenever the clock source "ticks". A clock is simply an object that supports registration of listeners and periodically invokes its listeners with a number. Open MCT supports registration of new clock sources that tick on almost anything. A tick occurs when the clock invokes callback functions registered by its listeners with a new time value.
An example of a clock source is the LocalClock which emits the current time in UTC every 100ms. Clocks can tick on anything. For example, a clock could be defined to provide the timestamp of any new data received via a telemetry subscription. This would have the effect of advancing the bounds of views automatically whenever data is received. A clock could also be defined to tick on some remote timing source.
The values provided by clocks are simple number
s, which are interpreted in the
context of the active Time System.
Defining and registering clocks
A clock is an object that defines certain required metadata and functions:
key
: Astring
uniquely identifying this clock. This can be used later to reference the clock in places such as the Time Conductor configurationcssClass
: Astring
identifying a CSS class to apply to this clock when it's displayed in the UI. This will be used to represent the time system with an icon. There are a number of built-in icon classes available in Open MCT, or a custom class can be used here.name
: Astring
providing a human-readable identifier for the clock source. This will be displayed in the clock selector menu in the Time Conductor UI component, if active.description
: An optionalstring
providing a longer description of the clock. The description will be visible in the clock selection menu in the Time Conductor plugin.on
: Afunction
supporting registration of a new callback that will be invoked when the clock next ticks. It will be invoked with two arguments:eventName
: Astring
specifying the event to listen on. For now, clocks support one event -tick
.callback
: Afunction
that will be invoked when this clock ticks. The function must be invoked with one parameter - anumber
representing a valid time in the current time system.
off
: Afunction
that allows deregistration of a tick listener. It accepts the same arguments ason
.currentValue
: Afunction
that returns anumber
representing a point in time in the active time system. It should be the last value provided by a tick, or some default value if no ticking has yet occurred.
A new clock can be registered using the addClock
function exposed by the Time
API:
var someClock = {
key: 'someClock',
cssClass: 'icon-clock',
name: 'Some clock',
description: "Presumably does something useful",
on: function (event, callback) {
// Some function that registers listeners, and updates them on a tick
},
off: function (event, callback) {
// Some function that unregisters listeners.
},
currentValue: function () {
// A function that returns the last ticked value for the clock
}
}
openmct.time.addClock(someClock);
An example clock implementation is provided in the form of the LocalClock
Getting and setting active clock
Once registered a clock can be activated by calling the clock
function on the
Time API passing in the key or instance of a registered clock. Only one clock
may be active at once, so activating a clock will deactivate any currently
active clock. Setting the clock will also trigger a 'clock' event.
openmct.time.clock(someClock);
Upon being activated, a clock's on
function will be immediately called to subscribe
to tick
events.
The currently active clock (if any) can be retrieved by calling the same function without any arguments.
Stopping an active clock
The stopClock
method can be used to stop an active clock, and to clear it. It
will stop the clock from ticking, and set the active clock to undefined
.
openmct.time.stopClock();
Clock Offsets
When a clock is active, the time bounds of the application will be updated
automatically each time the clock "ticks". The bounds are calculated based on
the current value provided by the active clock (via its tick
event, or its
currentValue()
method).
Unlike bounds, which represent absolute time values, clock offsets represent relative time spans. Offsets are defined as an object with two properties:
start
: Anumber
that must be < 0 and which is used to calculate the start bounds on each clock tick. The start offset will be calculated relative to the value provided by a clock's tick callback, or itscurrentValue()
function.end
: Anumber
that must be >=0 and which is used to calculate the end bounds on each clock tick.
The clockOffsets
function can be used to get or set clock offsets. For example,
to show the last fifteen minutes in a ms-based time system:
var FIFTEEN_MINUTES = 15 * 60 * 1000;
openmct.time.clockOffsets({
start: -FIFTEEN_MINUTES,
end: 0
})
Note: Setting the clock offsets will trigger an immediate bounds change, as
new bounds will be calculated based on the currentValue()
of the active clock.
Clock offsets are only relevant when a clock source is active.
Time Events
The time API supports the registration of listeners that will be invoked when the
application's temporal state changes. Events listeners can be registered using
the on
function. They can be deregistered using the off
function. The arguments
accepted by the on
and off
functions are:
event
: Astring
naming the event to subscribe to. Event names correspond to the property of the Time API you're interested in. A full list of time events is provided later.
As an example, the code to listen to bounds change events looks like:
openmct.time.on('bounds', function callback (newBounds, tick) {
// Do something with new bounds
});
List of Time Events
The events supported by the Time API are:
bounds
: Listen for changes to current bounds. The callback will be invoked with two arguments:bounds
: A bounds bounds object representing a new time period bound by the specified start and send times.tick
: Aboolean
indicating whether or not this bounds change is due to a "tick" from a clock source. This information can be useful when determining a strategy for fetching telemetry data in response to a bounds change event. For example, if the bounds change was automatic, and is due to a tick then it's unlikely that you would need to perform a historical data query. It should be sufficient to just show any new telemetry received via subscription since the last tick, and optionally to discard any older data that now falls outside of the currently set bounds. Iftick
is false, then the bounds change was not due to an automatic tick, and a query for historical data may be necessary, depending on your data caching strategy, and how significantly the start bound has changed.
timeSystem
: Listen for changes to the active time system. The callback will be invoked with a single argument - the newly active time system.timeSystem
: The newly active time system object.
clock
: Listen for changes to the active clock. When invoked, the callback will be provided with the new clock.clock
: The newly active clock, orundefined
if an active clock has been deactivated.
clockOffsets
: Listen for changes to active clock offsets. When invoked the callback will be provided with the new clock offsets.clockOffsets
: A clock offsets object.
The Time Conductor
The Time Conductor provides a user interface for managing time bounds in Open MCT. It allows a user to select from configured time systems and clocks, and to set bounds and clock offsets.
If activated, the time conductor must be provided with configuration options, detailed below.
Time Conductor Configuration
The time conductor is configured by specifying the options that will be
available to the user from the menus in the time conductor. These will determine
the clocks available from the conductor, the time systems available for each
clock, and some default bounds and clock offsets for each combination of clock
and time system. By default, the conductor always supports a fixed
mode where
no clock is active. To specify configuration for fixed mode, simply leave out a
clock
attribute in the configuration entry object.
Configuration is provided as an array
of menu options. Each entry of the
array is an object with some properties specifying configuration. The configuration
options specified are slightly different depending on whether or not it is for
an active clock mode.
Configuration for Fixed Time Mode (no active clock)
timeSystem
: Astring
, the key for the time system that this configuration relates to.bounds
: ATime Bounds
object. These bounds will be applied when the user selects the time system specified in the previoustimeSystem
property.zoomOutLimit
: An optionalnumber
specifying the longest period of time that can be represented by the conductor when zooming. If azoomOutLimit
is provided, then azoomInLimit
must also be provided. If provided, the zoom slider will automatically become available in the Time Conductor UI.zoomInLimit
: An optionalnumber
specifying the shortest period of time that can be represented by the conductor when zooming. If azoomInLimit
is provided, then azoomOutLimit
must also be provided. If provided, the zoom slider will automatically become available in the Time Conductor UI.
Configuration for Active Clock
clock
: Astring
, thekey
of the clock that this configuration applies to.timeSystem
: Astring
, the key for the time system that this configuration relates to. Separate configuration must be provided for each time system that you wish to be available to users when they select the specified clock.clockOffsets
: AclockOffsets
object that will be automatically applied when the combination of clock and time system specified in this configuration is selected from the UI.
Example conductor configuration
An example time conductor configuration is provided below. It sets up some default options for the UTCTimeSystem and LocalTimeSystem, in both fixed mode, and for the LocalClock source. In this configutation, the local clock supports both the UTCTimeSystem and LocalTimeSystem. Configuration for fixed bounds mode is specified by omitting a clock key.
const ONE_YEAR = 365 * 24 * 60 * 60 * 1000;
const ONE_MINUTE = 60 * 1000;
openmct.install(openmct.plugins.Conductor({
menuOptions: [
// 'Fixed' bounds mode configuation for the UTCTimeSystem
{
timeSystem: 'utc',
bounds: {start: Date.now() - 30 * ONE_MINUTE, end: Date.now()},
zoomOutLimit: ONE_YEAR,
zoomInLimit: ONE_MINUTE
},
// Configuration for the LocalClock in the UTC time system
{
clock: 'local',
timeSystem: 'utc',
clockOffsets: {start: - 30 * ONE_MINUTE, end: 0},
zoomOutLimit: ONE_YEAR,
zoomInLimit: ONE_MINUTE
},
//Configuration for the LocaLClock in the Local time system
{
clock: 'local',
timeSystem: 'local',
clockOffsets: {start: - 15 * ONE_MINUTE, end: 0}
}
]
}));
Included Plugins
Open MCT is packaged along with a few general-purpose plugins:
openmct.plugins.Conductor
provides a user interface for working with time within the application. If activated, configuration must be provided. This is detailed in the section on Time Conductor Configuration.openmct.plugins.CouchDB
is an adapter for using CouchDB for persistence of user-created objects. This is a constructor that takes the URL for the CouchDB database as a parameter, e.g.
openmct.install(openmct.plugins.CouchDB('http://localhost:5984/openmct'))
openmct.plugins.Elasticsearch
is an adapter for using Elasticsearch for persistence of user-created objects. This is a constructor that takes the URL for the Elasticsearch instance as a parameter. eg.
openmct.install(openmct.plugins.CouchDB('http://localhost:9200'))
openmct.plugins.Espresso
andopenmct.plugins.Snow
are two different themes (dark and light) available for Open MCT. Note that at least one of these themes must be installed for Open MCT to appear correctly.openmct.plugins.LocalStorage
provides persistence of user-created objects in browser-local storage. This is particularly useful in development environments.openmct.plugins.MyItems
adds a top-level folder named "My Items" when the application is first started, providing a place for a user to store created items.openmct.plugins.UTCTimeSystem
provides a default time system for Open MCT.
Generally, you will want to either install these plugins, or install different plugins that provide persistence and an initial folder hierarchy.
eg.
openmct.install(openmct.plugins.LocalStorage());
openmct.install(openmct.plugins.MyItems());