tRest with dynamic body

[lucTalend]

Hey ,  

I want to create a flow to get data from API ,to made that , I need to create export definition first.
In export definition I need to put from what date range , data need to be prepared.

So I thought that the simplest way to archive that will be use tJavaRow component where inside I will do that code :

String todayDate = TalendDate.formatDate("yyyy-MM-dd", new Date());
String yesterday = TalendDate.addDate(todayDate,"yyyy-MM-dd",-1,"dd");
String Definition = "{\"name\": \"Bulk Activity Export - Email Clickthrough\",\"fields\": {\"ActivityDate\": \"{{Activity.CreatedAt}}\",\"ActivityType\": \"{{Activity.Type}}\",\"EmailAddress\": \"{{Activity.Field(EmailAddress)}}\",\"EmailWebLink\": \"{{Activity.Field(EmailWebLink)}}\",\"SubjectLine\": \"{{Activity.Field(SubjectLine)}}\"},\"filter\": \"'{{Activity.Type}}' = 'EmailClickthrough' AND '{{Activity.CreatedAt}}' >= '" + yesterday + "' AND '{{Activity.CreatedAt}}' < '" + todayDate + "'\"}";
globalMap.put("Definition", Definition);

But then I cannot pass "Definition" value to the tRest component.

Current , my flow looks like :

For now , I've get all values from tSetGlobalVar component , and for static export definition works without no problem.

How to resolve that problem ?

Thank you , 

Lucjan 

[lennelei · Accepted solution]

Hi,

first of all, some tips:

String todayDate = TalendDate.formatDate("yyyy-MM-dd", new Date());
String yesterday = TalendDate.addDate(todayDate,"yyyy-MM-dd",-1,"dd");

//you can use following Talend methods
String todayDate = TalendDate.getDate("yyyy-MM-dd");
String yesterday = TalendDate.addDate(TalendDate.getCurrentDate(),-1,"dd");
//which is equivalent to
String yesterday = TalendDate.addDate(new Date(),-1,"dd");

Now, regarding your question :

If I understand correctly, you want to produce the json changing only the dates according to the current day?

In that case, you could directly put some java code in the tRest body :

"{\"name\": \"Bulk Activity Export - Email Clickthrough\",\"fields\": {\"ActivityDate\": \"{{Activity.CreatedAt}}\",\"ActivityType\": \"{{Activity.Type}}\",\"EmailAddress\": \"{{Activity.Field(EmailAddress)}}\",\"EmailWebLink\": \"{{Activity.Field(EmailWebLink)}}\",\"SubjectLine\": \"{{Activity.Field(SubjectLine)}}\"},\"filter\": \"'{{Activity.Type}}' = 'EmailClickthrough' AND '{{Activity.CreatedAt}}' >= '" + TalendDate.addDate(TalendDate.getCurrentDate(),-1,"dd")+ "' AND '{{Activity.CreatedAt}}' < '" + TalendDate.getDate("yyyy-MM-dd")+ "'\"}";

However, it will be hard to maintain as the body grows.

I would prefer to use something like this :

tFixedFlowInput -row-> tWriteJSONField -row-> tFlowToIterate -iterate-> tRest ...

In the tFixedFlowInput, you create all the required data for the json (name, fields, and so one) with correct values.

You then create your JSON with the tWriteJSONField.

The tFlowToIterate is used to put the JSON in globalMap and you'll use this in your tRest.

And if your "Definition" comes from a database, you can replace the tFixedFlowInput with whatever data source you nedd.

[lucTalend]

Thanks @lennelei - this export definition will be the same , only dates need to be changed - so your solutions is great !