[Good First Issues]: implement function "extract_between_delimiters" - 7 points

[Michaelg22]

Motivation

Vanus Functions are a series of pre-built functions worked within Vanus transformer. By choosing a function, users can specify the way that events will be changed.

It will be a good start if you decide to contribute to Vanus codes.

Details

Function name: extract_between_delimiters

args

• sourceJsonPath – The name of an existing path.
• targetJsonPath – The name of the new path to be created.
• startDelimiter – Indicating the character or characters that begin the delimited value.
• endDelimiter – Indicating the delimiter character or characters that end the delimited value.
  ..

Description

The function is used to extract value between the start delimiter and end delimiter from the source JSON path. Then assign the value to the target JSON path.

Extraction is base on the starting and ending delimiters.

Example

{
    "specversion" : "1.0",
    "type" : "com.example.someevent",
    "source" : "/mycontext",
    "subject": null,
    "id" : "C234-1234-1234",
    "time" : "2018-04-05T17:31:00Z",
    "comexampleextension1" : "value",
    "comexampleothervalue" : 5,
    "datacontenttype" : "application/json",
    "data" : {
        "appinfoA" : "Hi welcome to &&Vanus&",
        "appinfoB" : "efgs",

    }
}

After the function "extract_between_delimiters":

"pipeline":[
    {"command":["extract_between_delimiters","$.data.appinfoA", "$.data.appinfoC", "&&", "&"]}
]

The transformed event should look like this:

{
    "specversion" : "1.0",
    "type" : "com.example.someevent",
    "source" : "/mycontext",
    "subject": null,
    "id" : "C234-1234-1234",
    "time" : "2018-04-05T17:31:00Z",
    "comexampleextension1" : "value",
    "comexampleothervalue" : 5,
    "datacontenttype" : "application/json",
    "data" : {
        "appinfoA" : "Hi welcome to &&Vanus&",
        "appinfoB" : "efgs",
        "appinfoC" : "Vanus",
    }
}

How to implement

1. Fork the vanus repository.
2. Create a branch function-extract_between_delimiters
3. Create extract_between_delimiters.go under internal/primitive/transform/action/strings, and then implement the function.
4. Create extract_between_delimiters_test.go under internal/primitive/transform/action/strings for unit test.
5. Register your function in internal/primitive/transform/runtime/init.go.
6. Submit your PR

Contribution points

Each issue counts specific points based on its difficulty. Contributors earn the corresponding points if they solve that issue. Contribution points are used to describe the contributions contributors have made. They can also be used to get rewards when there are community events.

This issue counts 7 points.

How to claim to solve the issue

If you want to implement this function, please leave a comment in this issue like:

I'd like to implement this function, please assign this issue to me.

Vanus community will assign the issue to you on time.

[calmius]

I don't have a lot experience with Go, but looking through merged PRs, I think I get the gist, and I really want to try to implement this function, please assign this issue to me.

[Michaelg22]

Great I will assign this issue to you. Please also join our slack community for better future communication if any. @calmius Thanks