如何在Pentaho勺子中连接字符串？

Question

I am a newbie to Pentaho (installed today). I was able to do basic transformation in Spoon. Now I need to do some stuff, which I can't figure out how.

my input looks like

2012-09-17|garima|fbhjgjhgj87687jghgj88jgjj|garima#1347868164626|::ffff:120.56.132.137

3rd field is an ID, for which I need to get some information from a REST API

http://api.app.com/app/api/v1/feature/fbhjgjhgj87687jghgj88jgjj

What do I need to do in Spoon to get this done?

Also, data return will be in json format. how do I parse that?

Answer 1

You should first get your input with a CSV File Input using | as delimiter. Then you can get the 3rd field as a string.

Next you probably need to remove all spaces from this string with a String operations step. Look at the Remove special character column, and select space .

Then you need to concatenate it with your http address http://api.app.com/app/api/v1/feature/ . For this you'll use a Calculator step. At this step first create a new temporary field tmpAddr , with operation Define a constant value for ... (or something like this, sorry my spoon is in portuguese). At the Field A column you'll write your http address. It's a good practice, after you make this work, to set your address as a system variable so if it changes you don't need to replace it everywhere on your transformations (look at menu Edit -> System Variables ).

Now on the same Calculator step create another field, let's say MyAddress , with operation A+B . Choose for Field A the field tmpAddr you just created, and for Field B the 3rd field from your input.

Now on your stream you should have the full address as a field MyAddress . Connect a REST client step. Mark Accept URL from field and choose field MyAddress as URL Field Name . Set Application Type to JSON . Set Result Fieldname as MyResult .

If you need further JSON parsing you can add a Json input step. Set Source is defined in a field and select field MyResult as Get Source from field .

Answer 2

An alternate approach is to use the "Replace in String" step to append the string.

1. Set 'use RegEx' to Y
2. Set 'Search' to (.*)
3. Set 'Replace with' to http://api.app.com/app/api/v1/feature/$1
4. Set 'Whole Word' to Y

The parentheses in the regex set up a capture group that you can then insert into your replacement string with the $X syntax