jmeter csv data POST json collection - json

Question

JSON body for an HTTP request needs to look like:
{
"OrderId":"234",
"SupplierId":"JJ889",
"OrderedProducts": [
{
"ProductId":"123",
"Sku":"ABC123",
"Description":"Thing 1"
},
{
"ProductId":"435",
"Sku":"XYZ987",
"Description":"Thing 2"
}
]
}
And I have a CSV file that looks like:
ProductId,Sku,Description
123,ABC123,Thing 1
435,XYZ987,Thing 2
....
But when I substitute "ProductId":"${ProductId}" (and the other variables for sku and description) in the HTTP Request body data I end up with:
{
"OrderId":"234",
"SupplierId":"JJ889",
"OrderedProducts": [
{
"ProductId":"123",
"Sku":"ABC123",
"Description":"Thing 1"
},
{
"ProductId":"123",
"Sku":"ABC123",
"Description":"Thing 1"
}
]
}
How do I ensure my collection of products is unique (i.e. different CSV line) per request?

Answer 1

If you have always 2 products per request, just organize your CSV this way:
ProductId1,Sku1,Description1,ProductId2,Sku2,Description2
And use the new variable names.

Answer 2

Use combination of __StringFromFile() and __javaScript() functions like:
{
"OrderId":"234",
"SupplierId":"JJ889",
"OrderedProducts": [
{
"ProductId":"${__javaScript("${__StringFromFile(file.csv,,,)}".split("\,")[0],)}",
"Sku":"${__javaScript("${__StringFromFile(file.csv,,,)}".split("\,")[1],)}",
"Description":"${__javaScript("${__StringFromFile(file.csv,,,)}".split("\,")[2],)}"
},
{
"ProductId":"${__javaScript("${__StringFromFile(file.csv,,,)}".split("\,")[0],)}",
"Sku":"${__javaScript("${__StringFromFile(file.csv,,,)}".split("\,")[1],)}",
"Description":"${__javaScript("${__StringFromFile(file.csv,,,)}".split("\,")[2],)}"
}
]
}
__StringFromFile() function reads next line from file.csv each time it's being called
__javaScript() function allows executing arbitrary JavaScript code, in above case split() function to break the line into ProductId, Sku and Description.
See Functions and Variables User Manual chapter and How to Use JMeter Functions posts series for more information on JMeter functions.