REST connector sends different data format than it should

[markfarkas-camunda]

Describe the Bug

When I try to use the REST connector to call the /v1/variables/search Operate API it does not work with the same body which works in Swagger UI.

Steps to Reproduce

1. Start a process instance with Variables

{
"customerId":"ABC"
}

2. In this same process add a REST connector with the proper authentication and make an HTTP request to Operate (http://localhost:8081/v1/variables/search) with the body : {"filter": {"name":"customer","value":"{\"name\":\"aa\",\"id\":\"ABC\"}"}}
3. Call the /v1/variables/search in swagger (http://localhost:8081/swagger-ui/index.html#/Variable/search) with the JSON object provided in the REST connector's body.

Expected Behavior

Point 2 and point 3 should give the exact same result.
In reality: swagger call returns the items, but in the REST connector's response the items property is empty.

Environment

• OS: Windows 11
• Library version: latest
• Camunda version: latest

See also

https://camunda.slack.com/archives/C02UMKN3DTL/p1674054860769479

Relates to

camunda/camunda#9859

[markfarkas-camunda]

I was able to verify that the REST connector sends different body than the original input for body.
The reason behind this is escaping the escape character.

The original user defined body:

{
  "filter": {
    "name":"customer",
    "value":"{\"name\":\"aa\",\"id\":\"ABC\"}"
  }
}

The actual body used in the request:

{
  "filter": {
    "value": "{\\\"name\\\":\\\"aa\\\",\\\"id\\\":\\\"ABC\\\"}",
    "name": "customer"
  }
}

The OutboundConnectorContext object already contains these extra escape characters, so the issue comes from a deeper level.

The Zeebe team already created a bug ticket for this. Solving that ticket will automatically solve this issue as well.

At this point there is no further action required from connectors team.

I will leave the ticket in the backlog as a reference.

[AlexeiBaranov]

It seems to be a problem with Feel. The Feel engine must unescape string literals in the expression before using it, but it doesn't:

From other side, it works fine when we escape the value of the context variable:

ps:

[abbasadel]

Hey connectors team, this bug is currently resolved in Zeebe 8.3.4 release