Difference between revisions of "Triggers"

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:; Argument: '''values''' — [https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Object '''''Object'''''] containing the field values
 
:; Argument: '''values''' — [https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Object '''''Object'''''] containing the field values
 
:; Result: [[#Object entry|'''''Entry''''' object]] — the new entry in the library
 
:; Result: [[#Object entry|'''''Entry''''' object]] — the new entry in the library
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===== show() =====
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: Display the library
  
 
==== ''Library'' Properties ====
 
==== ''Library'' Properties ====

Revision as of 02:50, 28 December 2016

« Page as of 2016-11-27, editions Mobile 4.1.0, Desktop 1.0.6 »

A Trigger is a script that defines the processing of an entry whenever a particular kind of event takes place. Trigger scripts are written in JavaScript. When a trigger script is executed, it may perform actions like changing an existing entry, creating a new entry, executing an HTTP request, creating a file, performing data validation, etc.


Definitions

So, we define the following terms:

Event type
One of the following:
  • Creating an entry
  • Updating an entry
  • Deleting an entry
  • Opening an Entry Edit card
  • Adding an entry to Favorites
  • Removing an entry from Favorites
Phase of an Event
One of a predefined set of moments during entry processing for each Event type during which the user can intervene via a trigger script. See the table of events and phases below.
The Event type and the Phase determine the trigger script(s) to be run.
Trigger or Trigger Script
A script that may be defined to run when an event occurs for an entry
The trigger (Event type & Phase) and the corresponding trigger script are one-to-one.
When referring specifically to the script, it is called the trigger script. When referring to the Event type & Phase and its listing in the trigger list, it is referred to merely as a trigger.

Mode of script execution

The phase in which the trigger is activated defines its mode of execution — synchronous or asynchronous.

Synchronous script execution mode
Memento suspends user interaction and then executes the script. In the case of Before... phases, there is an impending operation that will take place unless the script forestalls it by calling cancel().
Time-consuming operations are not recommended in this mode.
Asynchronous script execution mode
The script runs in the background; user interaction is not suspended. Usually, asynchronous scripts are used in the last phases of the action, after any save or other operation is initiated.


Events & Phases

These are the defined Event types, Phases, and their corresponding modes of execution.

THE DEFINED EVENT TYPES & THEIR PHASES
Event type Phase Execution mode
Creating an entry Opening an Entry Edit card synchronous
Before saving the entry synchronous
After saving the entry asynchronous
Updating an entry Opening an Entry Edit card synchronous
Before saving the entry synchronous
After saving the entry asynchronous
Deleting an entry Before deleting the entry synchronous
After deleting the entry asynchronous
Opening an Entry View card Before window display synchronous
After window display asynchronous
Adding an entry to Favorites Before the operation synchronous
After the operation asynchronous
Removing an entry from Favorites Before the operation synchronous
After the operation asynchronous

Creating an entry

This event starts when a user has requested that a new entry be added to the library, normally by pressing the + button on the Entries List screen. It ends after the entry is saved to storage — or else not, depending on the processing of the entry.

Phases

This event has three phases. In sequence:

1. Opening an Entry Edit card (synchronous)
The script will be called once the Entry Edit card is open and before any data is displayed.
Initial field values (defaults) may be set.
2. Before saving the entry (synchronous)
The script will be called after the user has pressed the Checkmark icon and before the entry has been saved to storage.
The entered data may be validated; if validation fails, the save may be forestalled and control sent back to the Entry Edit card so the user may fix the errors.
Once the data is validated, this phase is an opportunity for many other functions to be performed to get data to add to the entry to be saved.
3. After saving the entry (asynchronous)
The script will be called once the save of the entry has been initiated and will continue in parallel with final processing of the new entry.
If you want to do something whenever a new entry is added, but not before the data is saved, this is the place to do it.

Updating an entry

This event starts when a user has requested that an existing entry be edited (updated) within the library, normally by pressing the Pencil button on the Entry View card. It ends after the entry is resaved to storage — or else not, depending on the processing of the entry.

Phases

This event has three phases. In sequence:

1. Opening an Entry Edit card (synchronous)
The script will be called once the Entry Edit card is open and before any data is displayed.
2. Before saving the entry (synchronous)
The script will be called after the user has pressed the Checkmark icon and before the entry has been saved to storage.
The entered data may be validated; if validation fails, the save may be forestalled and control sent back to the Entry Edit card so the user may fix the errors.
Once the data is validated, this phase is an opportunity for many other functions to be performed to get data to add to the entry to be saved.
The script could be used to update some entry data based on other entry data, to keep it all coordinated.
3. After saving the entry (asynchronous)
The script will be called once the save of the entry has been initiated and will continue in parallel with final processing of the new entry.
If you want to do something whenever an existing entry is updated, but not before the data is saved, this is the place to do it.

Deleting an entry

This event starts when a user has requested that an existing entry be deleted (actually, moved to the library's Recycle Bin) within the library, normally by pressing the Trash Can button on the Entry View card. It ends after the entry is moved to the Recycle Bin — or else not, depending on the processing of the entry.

Phases

This event has two phases. In sequence:

1. Before deleting the entry (synchronous)
This script will be called after the user has requested the deletion of the entry and pressed Yes on the "Do you really want to?" card, but before taking the action.
Since the user has at this point already confirmed that he or she really wants to delete that entry, what else needs to be done before doing the delete? And what would cause the delete to need to be forestalled? If the delete is to be forestalled, the script could call cancel() and inform the user as to why via message(), and let the user reconsider what to do.
Mainly, help the user reconfirm that the deletion should take place, and if not, call cancel() and inform the user (via message()).
2. After deleting the entry (asynchronous)
This script will be called after the delete operation is initiated and will continue as that operation takes place.
Anything you want to do whenever an entry is deleted should be done in this script.

Opening an Entry View card

This event starts when the user has selected an entry for view and ends after the entry had been displayed.

Phases

This event has two phases. In sequence:

1. Before window display (synchronous)
This script will be called before the entry is displayed. This provides the opportunity to alter or augment the data before it is seen by the user.
2. After window display (asynchronous)
This script will be called after the data display had been initiated, providing the opportunity to perform an action each time an entry had been viewed, such as logging or timestamping.

Adding an entry to Favorites

This event starts when the user has pressed an empty Star icon to make the current entry a Favorite and ends once it has been made a Favorite.

Phases

This event has two phases. In sequence:

1. Before the operation (synchronous)
This script is run just before the entry is made a Favorite.
Data validation could be done; perhaps only certain entries are allowed to be Favorites.
2. After the operation (asynchronous)
This script is called after the entry has been made a Favorite.
This action could be logged, for instance, or it could trigger an action on some other app.

Removing an entry from Favorites

This event starts when the user has pressed a filled Star icon to remove the current entry from Favorites and ends once it has been removed.

Phases

This event has two phases. In sequence:

1. Before the operation (synchronous)
This script is run just before the entry is removed from Favorites.
Confirmation of the user's intent could go here.
2. After the operation (asynchronous)
This script is called after the entry has been removed from Favorites.
This action could be logged, for instance, or it could trigger an action on some other app.


Security

Since the scripts have access to more actions than a user does, they require additional permissions.

The user must define these permissions manually for each library.

To open a card to set permissions for scripts, open the library triggers list and click the Shield icon on the toolbar. Permissions must be set separately on each device. Permissions are not synchronized between devices.

Permissions for scripts

Library permission
determines which other libraries can be affected by the script. You can grant access to all libraries or select only certain libraries. This authorization is required for the libByName() function.
Read permission
grants the script read access to a file
Write permission
grants the script write access to a file
Network
grants to the script the right to execute HTTP requests


Creating a trigger

Each library can have a number of triggers; multiple triggers may exist for each Event type and Phase. To see the list of triggers, open the library, open the menu, and then select Triggers.

To create a trigger, press the 3-dot icon in the upper-right corner of the screen to open the Action Menu; then press Triggers to open the list of existing triggers; then click +. You must then identify the Event type & Phase and write a trigger script that performs the necessary actions.

Writing a Trigger Script

Trigger scripts are JavaScripts. See links to JavaScript documentation below.

Event & Phase
Make sure to understand the Event & Phase you are scripting. This will dictate a number of things, such as whether data is present already or not, whether cancel() makes sense or not, whether the user is waiting for script execution or not, and so on.
Globals get you started
Note the global functions in the sections below; they generally get you started by providing needed information.
Inform the user
Keep the user informed. For instance, if a script is running in a synchronous phase, then a call to cancel() may make sense, but the user won't know what happened and what to do next unless you provide that information, probably via message().
Debug your script
Of course, you can put calls to message("Your message") to help to test your script. To further assist, the log("Your message") global function can be used to send messages to a log without bothering the user about it. By default, the log is directed to the Android developer console; to have it directed instead to a file, go to Memento Settings under Debug and turn on Triggers Logs. You can set the location for the file, but by default, it will be in memento/logs. Both messages from calls to log() and system log messages, including JavaScript exceptions, go into the log.
Permissions
Certain functions require special permissions; read above about that. One such function is libByName(). Others include the file access and HTTP functions.
No return
As of release 4.0.0 of the mobile edition, the script is executed as a top-level script and not as a called function; therefore, for instance, the return statement is not appropriate in a trigger script.


Libraries and Entries

Library Global Functions

entry()

Get the entry of the Event. For example, if script is triggered by an Update Entry event, this function will return the entry being updated.
This function is available to all Events and Phases, with the exception of Creating an entry > Opening an Entry Edit card; for this action, use the function entryDefault().
Result
Entry object — the current entry

entryDefault()

Get the Entry object containing the default field values for the entry not yet created. This feature is available specifically and only for the Event Creating an entry & Phase Opening an Entry Edit card.
Result
DefaultEntry object

lib()

Get the library of the triggering event
Result
Library object — the current library

libByName(name)

Find the library by name. Permission to use the library is required, based on security settings.
Argument
The name of the library to find
Result
Library object — the library identified by the argument name, if found. Otherwise null.


Object Library

This object provides access to library entries. You can work with the current library — the lib() — or any other library in the database — libByName(). This function provides the ability to update existing entries and create new ones.

Library Methods

entries()
Get all the entries of the library
Result
Array object containing entries, sorted by the time of their creation, from newest to oldest
find(query)
Search field values within entries in the library matching the given query. This search is similar to searching via Memento's user interface.
Argument
query — the search string
Result
Array object containing matching entries. Entries are sorted by the time of their creation, from newest to oldest.
findByKey(name)
Search all entries by the Entry Name. The library must be set for unique Entry Names.
Argument
name — the Entry Name field value
Result
Entry object, if found. Otherwise, null.
create(values)
Create a new entry in the library
Argument
valuesObject containing the field values
Result
Entry object — the new entry in the library
show()
Display the library

Library Properties

title — The name of the library


Object Entry

This object holds an entry of the current library, allowing the setting of field values

Entry Methods

set(name, value)
Set the value of the named field. Calling this method results in immediate writing of the value to the library.
Arguments
name — name of the field
value — the value of the field
field(name)
Get the value of the named field
Argument
name — name of the field
Result
The value of the field. The type of the result depends on the type of the field.

Entry Properties

title — entry name
description — entry description
favorites — true, if the entry is in Favorites
deleted — true, if the record is deleted (it is in the Recycle Bin)


Object DefaultEntry

Template with default values for a new entry. This feature is available specifically and only for the Event Creating an entry & Phase Opening an Entry Edit card.

DefaultEntry Methods

set(name, value)
Set the value of the field
Arguments
name — the name of the field
value — the value of the field


Libraries Examples


Data Validation

Using scripts, you can check the correctness of input data and deny saving of data that fail the test. For example, perhaps a field integer values ​​are allowed only from 0 to 200.

Add a Create trigger
Set Event to Creating a new entry, Phase to Before saving the entry. It will run synchronously.
Add an Update trigger
Set Event to Updating an entry, Phase to Before saving the entry. It will run synchronously.
Trigger script:
var num = entry().field("Number"); // Get value of field Number
if (num < 0 || num > 200) {        // Test for value matching allowable range
 message("Wrong range");           // If value is outside range, display message
 cancel();                         // Cancel the operation
}
Set default values
If default values cannot be set using the user interface, they can be set using a script.



Previous value of another field

Suppose there is a library containing daily mileage of daily walks or use of a car or bicycle. Suppose the library has a StartingMileage field and a Mileage field. When an entry is created, the field StartMileage must get data from the field Mileage in the previous entry.

Add a new trigger
Set Event to Creating an entry and Phase to Open the Entry Edit card. It will run synchronously.
Trigger script:
var entries = lib().entries();                   // Get current library & array of its entries
if (entries.length > 0) {                        // Check that array is not empty;
                                                 //   otherwise exit,
                                                 //   since there is no previous entry.
prevMileage = entries[0].field("Mileage");       // The array is sorted newest to oldest,
                                                 //   so newest entry in the array
                                                 //   on top with index of 0.
entryDefault().set("StartMileage", prevMileage); // Set value of field Mileage
                                                 //   from the previous entry
                                                 //   as default value for field StartMileage.
}



Beginning of the next day

Suppose you need to identify the beginning of a new day in the DateTime field. (The script requires connection of the JavaScript library moment.js moment.js.)

Add new trigger
Set Event to Creating an entry and Phase to Opening an Entry Edit card. It will run synchronously.
Trigger script:
var m = moment().add(1,'d'); // Using the moment.js library function moment(),
                             //   get the current time, and add 1 day
m.hour(8).minute(0);         // Set the time to hour 8 and minute 0
entryDefault().set("Date",
    m.toDate().getTime());   // Use that as the default value for the field Date



New entry in one library triggers new entry in another

Suppose that after a new application for membership is validated, a new member should be created. We have libraries Applications & Members. After a new Applications entry is entered and before it is saved, we want to validate the application, and if it passes, we want to create a new entry in Members.

Fields
Library Applications has fields Date, Name, City, Years in city, Type.
Library Members has fields Name & Type.
Set library permission
The Applications library must be permitted to access other libraries via libByName().
Within Triggers, press the shield icon to view Permission settings.
Add new trigger
Add a new trigger to the Applications library.
Set Event Creating a new entry, Phase Before saving the entry.
(A similar trigger could be set for Event Updating an entry Phase Before saving the entry, but only if a change in a field value is to trigger the add of the new member.)
Trigger script:
// Get the application entry that's being saved and call it e
//     (because you may use it a lot)
// With that, you can readily reference fields
//     in the new application entry about to be saved

var e = entry();

// If you have any checks on the values of fields the user entered,
//     you could do them here
// If any validations fail, call cancel() to forestall the save
// The user remains in the Entry Edit card
//     and will be advised the application does not pass criteria

if (e.field("Years in city") <== 2) {  // Sample field validation
    message("Application inadequate"); // You'll want more
    cancel(); // This will abort the save, but continue the script
}

else {      // Add a new member only if application is adequate

// From here on, the new application will be saved,
//     so we must also create the new member entry

// To create the new member, we need to reference Members

    var members = libByName("Members"); // This requires permission (see above)

// Start a new entry for Members

    var newMember = new Object();

// Set member fields from application data and add the new Members entry

    newMember["Name"] = e.field("Name");
    newMember["Type"] = e.field("Type");
    members.create(newMember);
}




Ensuring unique non-Name field value

The goal is to ensure that a particular field value is unique within the library.

The ideal way to do this is to make the field the one and only Entry Name field and then set the Entry Name to be unique. Then, Memento will take care of ensuring this for you.

To do this, go in the Library Edit screen to the MAIN tab of the library and turn on the switch "The Entry Name is unique". Then go to the FIELDS tab and ensure that your field and only that field has the role Entry Name. Do that by editing the field, and under Display Options, you'll see "Display in the list as"; the choices will include Entry Name.

Now, if your library needs some other Entry Name, and you nevertheless want to ensure that a different field is unique within the library, then, yes, you'll need some code.

The best way, if you're just starting to enter entries into your library, is to make sure they're unique from the outset, so from the Entries List screen, pick Triggers from the menu. Press the + (plus) button to add a trigger, set the Event to "Creating a new entry" and the Phase to "Before saving the entry".

Fields
The field in the current library — that is to be unique among the entries of the library — is myField.
Add new trigger
Add a new trigger to the library.
Set Event Creating a new entry, Phase Before saving the entry.
(A similar trigger could be set for Event Updating an entry Phase Before saving the entry — for instance, if the library already has entries in which myField may not be unique.)
Trigger script:
var myField = entry().field("myField");            // Value of myField
var entries = lib().entries();                     // Array containing all entries

var unique = true;                                 // Presuming, initially
for (var ent = 0; ent < entries.length; ent++) {   // Loop through all entries
    if (entries[ent].field("myField") === myField) // If there is ever a match,
        unique = false;                            // Remember it
}

if (!unique) { // If not unique,
    cancel(); // Disallow the save
    message("myField is not unique. Try again.");  // Tell the user
}




Working with files

With scripts, you can read or write files located in the device's internal memory or on the SD card. All file operations are performed by the File object, which is obtained via a global function called file().

To work with the files, the library should have read/write file access.

File Global Functions

file(name)

Open a file for read or write operations. If the file with the specified name does not exist yet, it will be created.

Argument
name — The name and the full path to the file. For example, if the file is located on the SD card, the path should be something like /sdcard/example.txt.
Result
File object


Object File

This object is returned by the global function file() and provides access to the requested file. After reading or writing, the file should be closed using the method close().

File Methods

readAll()
Reads all lines of the file, and then closes the file
Returns
Array containing the lines of the file
readLine()
Reads the next line from the file stream
Returns
The line
readLines()
Reads the remaining lines from the file stream
Returns
Array containing the remaining lines of the file
readChar()
Reads the next character from the file stream
Returns
The character
write(text)
Write string(s). Take a variable number of arguments, converts each argument to a string, and writes that string to the file stream.
writeLine(text)
Write strings and a newline to the file stream
close()
Close the file. It can subsequently be reopened.

File Properties

exists
true — if and only if the file exists; false otherwise
length
The length, in bytes, of the file, or 0L if the file does not exist.
getLineNumber
Get the current line number
Returns
The line number, or position, in the file


Files Examples


Writing & reading from a file

Add trigger(s)
This script could be a part of any phase of any event.
Trigger script:
f = file("/sdcard/myfile.txt"); // Open myfile.txt on the SD card
                                // If no file, it will be created
f.writeLine("one");             // Write "one" as a line to the file
f.writeLine("two");
f.writeLine("three");
f.close();                      // Close & save. Until closed,
                                //   the file is still empty
var a = f.readLines();          // Read all lines into array a



Save an entry to a file in XML format

The entry includes fields: id , title , date.

Add trigger(s)
This script could be a part of any phase of any event.
Trigger script:
var xml = '<record id="' + entry().field("id") + '">' +  // Format XML record
'<title>' + entry().field("title") + '</title>' +        //     from entry field values
'<date>' + entry().field("date") + '</date>' +
'</record>';
f = file("/sdcard/" + entry().field("title") + ".xml");  // File name is Entry Name
f.write(xml);                                            // Save XML data to the file
f.close();                                               // Close the file




Processing an HTTP request

Scripts can send HTTP requests to Web services through their APIs. Processing for HTTP requests allows integration between Memento and the system. All file operations use the Http object, which works through global function http().

HTTP requests must fulfill two requirements:

  1. Script execution must be asynchronous, so HTTP requests go in the last Phase of an Event.
  2. The library should have the permission Network.


Object Http

Interface for processing HTTP requests

Http Methods

get(url)
Execute HTTP get request
Argument
url — HTTP address, starting with http or https
Result
HttpResult — Object containing the result of the execution of the HTTP request


Object HttpResult

Result of the execution of the HTTP request

HttpResult Properties

code — HTTP code of the response, if the request is successful (usually 200).
body — The response in text form


Http Examples


Currency Conversion

Suppose the library contains two fields: PriceUSD and PriceEUR. The user will enter the value in PriceUSD and the value in Euros will appear in PriceEUR according to the current exchange rate.

Add new trigger
Set Event Create a new entry and Phase After saving the entry. It will run asynchronously.
Trigger script:
result = http().get("http://api.fixer.io/latest?base=USD"); // Use http://fixer.io/ for
                                                            // conversion rate in JSON
usdToEur = JSON.parse(result.body)["rates"]["Eur"];         // Use JavaScript object JSON
                                                            // to parse the result
entry().set("PriceEUR",
    entry().field( "PriceUSD") * usdToEur );                // PriceUSD * conversion rate
                                                            // for value for PriceEUR



Creating a Task in the Todoist App

Todoist — A Web service and mobile app for task management. Todoist allows task creation via API [1]. In the following example of task creation, text will be taken from the Memento library entry.

Add a new trigger
Set Event to Creating a new entry or perhaps Update an entry. Set Phase as appropriate.
Trigger script:
// Create a JSON command for Todoist task creation
//     using the format described in [https://develop.todoist.com/#add-an-item].
// This command should include a unique identifier
//     created using the guid() global function.
var commands =
    '[{"uuid":"' + guid() + '","temp_id":"' + guid() +
    '","type":"item_add","args":{"content":"' + entry().field("Task") + '"}}]';

// Execute the HTTP request. An attribute called '''token''' is used
//     for authorization in Todoist.
// It is available in the Todoist Account setting.
// Since the text of the task can include symbols
//     not allowed in a URL request,
//     use the standard function encodeURIComponent() to filter them out.
result = http().get("https://todoist.com/API/v7/sync?token=15281e8e4d499dаff817af0b14112eac3176f9dc&commands=" +
    encodeURIComponent(commands));

// Show the user a message indicating successful creation of the task.
if (result.code == 200)
    message('Task has been successfully created");




Interaction with the System

System Global Functions

message(text)

Shows the user a brief notification
Argument
text — Text of the notification

cancel()

Stop the system operation that caused the event. Many triggers can be a result of an entry manipulation (create, update, delete, etc). The cancel() function can be used during the phases that precede the system operation. For example, this function can be used during data validation before the entry is saved.

system()

Obtain information about the system
Result
System object

log(text)

Write a line to the log file
Argument
text — text to be written to the log

guid()

Generates random text identifier
Result
Random string identifier

intent(action)

Create an information exchange object — Intent. This function can send a request for action to another application.
This function is available only on Android.
Argument
action — Line that defines standard action (eg, view, pick)
Result
Intent object — Information exchange object
After the object is received, the data will be added to it, and then sent via send().
Android has many built-in actions. A list of these actions can be found here.


Object System

This object contains information about the system.

System Properties

os — Name of the operating system executing the script


Object Intent

Information exchange object. This object is created by using the global function intent().

Intent Methods

data(uri)
Define URI to reference the data
Argument
uri — URI referencing data to which the action will be applied. It can be contact ID, path to the file, phone number, etc.
mimeType(mime)
Define MIME type of the data
Argument
mime — MIME type of the data on which the operation will be performed
extra(key, value)
Define additional data as key-value pairs, as necessary for execution of the required action. Similar to how URI data can be required for certain actions, other actions may require extra data in this format.
Arguments
key and value
extraLong(key, value)
Define additional data as key-value pairs, where data type needs to be Long
Arguments
key and value
send()
Send a message


System Examples


Script to open a screen for dialing a number

Suppose a library contains a field called Phone containing a phone number.

Add a new trigger
Set Event to Opening an Entry View card, Phase to After display of the entry.
Trigger script:
i = intent("android.intent.action.DIAL"); // Create information exchange object Intent
                                          // with the action of DIAL
i.data("tel:"+entry().field("Phone"));    // The data will be the phone number obtained
                                          // from the field Phone
i.send();                                 // Send the message



Script to open app to send SMS message

The phone number will be obtained from the field Phone and the text of the message will be obtained from the fields ContactName and Notes.

Add a new trigger
Set Event to Opening an Entry View card, Phase After display of the entry. It will run synchronously.
Trigger script:
msg = "Dear, " +
    entry().field("ContactName") +
    "\n" + entry().field("Notes");          // Form the message from ContactName & Notes
i = intent("android.intent.action.SENDTO"); // Create intent object to open the app for sending
i.data("smsto:"+entry().field("Phone"));    // Provide the phone number in format smsto:number
i.extra("sms_body" , msg);                  // Insert the text of the message to sms_body
i.send();                                   // Send the message



Script to insert an appointment into Google Calendar

Suppose a library contains the time and name of an appointment.

Add a new trigger
Set Event to Creating a new entry, Phase to Before saving the entry. It will run synchronously.
Trigger script:
i = intent("android.intent.action.INSERT");       // Create Intent object
i.data("content://com.android.calendar/events");  // Data contains Google Calendar URI
i.extra("title", entry().field("Title"));         // Get event name from field Title
i.extra("description",
    entry().field("Description"));                // Get description from field Description
i.extraLong("beginTime",
    entry().field("Begin").getTime());            // Get start time from field Begin
                                                  // Begin is of type DateTime
                                                  // Additional parameter is of type Long,
                                                  // so extraLong() is used for conversion.
i.extraLong("endTime",
    entry().field("End").getTime());              // Get end time from the field End
                                                  // Requires same conversion as above
i.send();                                         // Send the message




JavaScript links

W3Schools
JavaScript Tutorial A pleasant, fairly complete, and useful tutorial on JavaScript
Best on a computer or tablet in landscape. On a phone or tablet in portrait, scroll to the bottom for navigation.
Mozilla Developer Network
JavaScript Guide Shows you how to use JavaScript, gives an overview of the language, and presents its capabilities & features
JavaScript Reference The entire JavaScript language described in detail
Introduction to JavaScript Introduces JavaScript and discusses some of its fundamental concepts
JavaScript Tutorial A re-introduction. JavaScript is often derided as being a toy, but beneath its simplicity, powerful language features await.
JavaScript 1.7 The JavaScript release upon which Memento is currently based
About JavaScript Jumping off point in learning about JavaScript