Posts

Calendar- Date Time in PCS - Header

Dealing with Dates and Times in Oracle Process Cloud Service

Introduction

Oracle Process Cloud Service (PCS) is great! You can build process-based applications in two shakes of a lamb’s tail, much quicker than most Low Code platforms in the market. Of course, you can’t, or at least shouldn’t, develop any “normal” master-detail CRUD application with Oracle Process Cloud Service. If you need this kind of applications perhaps Oracle Application Builder Cloud Service will suit you better, but for process-centric applications, it’s a hard to beat tool.

As you may know, Oracle also has an on-premise product, called Oracle BPM, which features a similar codebase, but it features a more advanced and complex UI and it takes a bit more time to produce a similar application.

Oracle PCS really shines for its simplicity and ease of use, because the UI was streamlined and is much more focused. However, all this optimization and streamlining led to decisions to simplify the UI and some features present in Oracle BPM are not present in Oracle PCS. Most of them we won’t really need except for 1% of all our application needs, but a few are a more common necessity. The capacity to use functions to manage and operate dates and times fit this last set.

Oracle BPM allows you to manipulate dates using several options, with Data Associations and Script tasks perhaps being the most common. In Oracle PCS, the Data Associations don’t allow you manipulate dates nor retrieve the current Date / Time, and script tasks plain and simply are not available.

It’s possible to create services that do whatever we need to do with dates and then call them in Oracle PCS, but sometimes we want a more direct approach.

The Use Case

Let’s consider the following case:

We have a simple approval process with 3 steps. Every time there’s a response to a task, we want to record which response was and at which date and time it was made. We also want to show this information to the user, in the task web form, and we want that the whole process takes a calculated amount of time as the most, with it automatically finishing up after that amount.

Something a bit like this:

The Use Case process

The Use Case process

And the web form:

The Use Case web form

The Use Case web form

 

Notice that Oracle PCS automatically creates a data object in the process, of the same type as the start form.

Automatically created data object corresponding to our web form

Automatically created data object corresponding to our web form

Also, all task data associations are done automatically, without the need to do this manually, when you set the task form.

Choose the web form for the task to use

Choose the web form for the task to use

Automatic Data Associations - Cool Stuff!

Automatic Data Associations – Cool Stuff!

Remember that we want to fill each of the decision fields with both the Outcome of the last response and the date and time of that response.

If we try to so it through the web form functions, you’ll notice that you can only set a field to the current date/time. This would change the value of the field “When?” every time the user was shown the form. This is not what we want.

Trying to automatically fill this field

Trying to automatically fill this field

... and you can. But that's not what you want.

… and you can. But that’s not what you want.

Also, you can’t do calculations between fields which are of type date/time. Let’s say you also want a new field which tells you the number of days between the date of the first decision and the last one. How can you calculate this in the form?

Common sense would lead us to try to subtract the value of the field that holds the date/time of the first decision, from the value of the field that holds the date/time of the last decision. Unfortunately, this doesn’t work, as you can see below (31 May – 18 May = 0)

Our form doesn't calculate the Nr of days correctly

Our form doesn’t calculate the Nr of days correctly

The Nr of days calculation function

The Nr of days calculation function

We can also try the data association route, but, as we can see from the image below, there are no functions to deal with dates in this part.

Data Associations Expression Builder - Data Objects

Data Associations Expression Builder – Data Objects

Data Associations Expression Builder - Operators

Data Associations Expression Builder – Operators

Finally, as there are no Script Tasks, as you have in Oracle BPM, you can’t actually program this in your process.

So, how can we do this?

We cheat!

Let’s try to use a Business Rule for this. By placing a Business Rule after each task, we guarantee an immediate execution right after the decision is taken and we record the rule execution date/time as the decision date.

Business Rules Calendar objects

Business rules get an input, do some magic, and produce an output… pretty much as any other task in our process. What makes them special is the amount of magic one can do inside them.

When we create a decision, we can use a lot of Java functions, including a few related to treating dates and times.

So we create a Business Rule, setup the input and output as objects of the type of the web form (this makes it easier to do the data associations) and, once we enter the decision screen we just create a new General Rule.

Creating your General Rule

Creating your General Rule

Then we create a true condition in the “If” part of the rule, as we want it to always execute, and in the “Then” part, we specify that we want to modify the object that we specify in the Drop Down List (in the example below the object is called “Other”).

Our Rule Configuration

Our Rule Configuration

We click on the pencil icon and choose the field in which we want to do the date processing (click on the magnifying glass). We are taken into the Condition Browser, where we can access the Expression Builder

Condition Browser

Condition Browser

Business Rules Expression Builder

Business Rules Expression Builder

As you can see, this expression builder is much more advanced than the one available in the Data Associations dialog, with a few more tabs, including the Functions.

In here we can do calculations with our dates, set them as we want.

So we’ll grab the CurrentDate.date.time calendar and apply the JavaDate.to datetime string to it, like so:

Our Date expression

Our Date expression

And that’s it. This will calculate the current date and time, put it in the output object, which is our web form.

Now we only need to repeat for all tasks. A bit like this:

Our Use Case process with Business Rules

Our Use Case process with Business Rules

I hope that this article can help you do more complex calculations and extend the normal use of Oracle PCS, to cope with more business scenarios.

If you have any questions please place them in the comments box below.

José Rodrigues

P.S: All of this could also be done with the help of ICS, JCS or ACCS. I’ll write about it in a couple of weeks.

Post header image by Sebastien Wiertz

Process Timers

Process Timers – Controlling the time in which your process executes

Hello everybody,

Following up a series of questions around setting timers in the Oracle Community forums, I decided to write this article to try and guide their use and how these can be used to control process execution.

Let’s start!

The Use Case

We’ll begin by setting up the scenario in which we’ll have to control our process flow.

Imagine that you want to have a part of your process that executes immediately if the current time is between 08:00am and 04:00pm (16:00 hours for us Europeans), or wait until 08:00am if it’s outside that interval.

It’s frequent to have some kind of control in parts of the processes, for instance when you want to send SMS to your customers. You certainly don’t want to do it at 03:00am.

How will we make this?

We should use a Catch Timer event, of course, and XPATH’s DateTime functions to check the current time and to set the timer to way for next morning’s 08:00.

The Catch Timer event has several ways to be configured (triggered at specific dates and times, on a specific schedule – every day at 10:28:00 (repeatable), or in a time cycle – every 2 minutes), but we’ll focus on the one where we configure the timer to wait for a specific time and date. More on the others perhaps in another article.

We’ll illustrate the use of timers with an example process. You can, of course, adapt it to your needs.

Defining the execution conditions 

So you start by defining a gateway that will split the execution between:

  • Immediate
  • Wait for 08:00am
    • This will have to be split into prior to midnight and after midnight. but for now, we’ll consider the scenario of only two options.

So, you set the expression on the conditional flow that will do the immediate execution, leaving the condition that must wait for 08:00 as the unconditional (default) branch.

The expression should be something like this:

Timer Setting

Timer Setting

xp20:hours-from-dateTime(xp20:current-dateTime()) >= 8  and xp20:hours-from-dateTime(xp20:current-dateTime()) <= 16

The function xp20:current-dateTime() gets the current Date and Time of when the decision is evaluated.

The function xp20:hours-from-dateTime(xs:dateTime) gets the ‘Hours’ integer from a dateTime object.

So you check if the current time is after 08:00am and before 04:00pm.

  • If it is, it follows the Green Light path, i.e. the immediate execution path.
  • If not, it will follow the Red Light path, and will wait on the timer for a green light (until 08:00am the next day, as per the requirements)

For the test process comprehension, check the process flow below.

Timer Test Process

Timer Test Process

So, only one more step to go: Setting the timer to the next 08:00am available.

This is achieved by setting the Timer implementation first to Type=Time Date (red arrow) and then setting the appropriate XPATH expression (orange arrow)

Timer Type Setting

Timer Type Setting

The XPATH expression is as follows:

xp20:add-dayTimeDuration-to-dateTime(xp20:current-date(),’P01DT08H’)

The add-dayTimeDuration-to-dateTime(xs:dateTime,formattingString) function adds an interval of date/time to a dateTime object.

The interval is set using the format ‘PyyYmmMddDThhHmmMssS‘.

The xp20:current-date() function returns the current date without the time associated, meaning it considers time = 00:00:00.

So, we’re stating that we want to add to the current date the amount of 01 day and 08 hours.

Warning

You would think that this solves the issue, but not quite. It solves the issue if the process reaches the decision point until midnight. After midnight, you can’t add a whole new day and then another 08 hours.

So you should split your flow further to handle these two scenarios:

  • Wait occurs prior to midnight => XPATH Expression interval = ‘P01DT08H’
  • Wait occurs after midnight => XPATH Expression interval = ‘P00DT08H”

I’m pretty sure there are other ways to do it, but I decided to do it like this:

Timer Process Final

Timer Process Final

In which I set the XPATH for Time Date type of the other Timer (Red Light / After Midnight) as

xp20:add-dayTimeDuration-to-dateTime(xp20:current-date(),’P00DT08H’)

So this should solve the case.

I added the project file for this:

CommunityTimerDefinition

Cheers

Maverick (José Rodrigues)

Post Header image by Henrique Simplicio