Query Params unable to have duplicate keys

[mikequentel]

Problem

Unable to use duplicate keys in the Query Params user interface.

Expected behaviour

User can have duplicate (even multiple duplicate) keys, so the URL params will be like this:
myparam=valueA&myparam=valueB&myparam=valueC so that a variable represented by myparam []string can be populated.

Observed behaviour

Grafana only passes one of the duplicate keys, like this: myparam=valueC, ignoring the other myparam keys.

Work-around solution

Enable the use of a comma-delimited string for the value; then check for this:

	issueLinkTypeNameExcludes, issueLinkTypeNameExcludesParamExists := c.GetQuery("issueLinkTypeNameExcludes")
	if issueLinkTypeNameExcludesParamExists == true {
		if strings.Contains(issueLinkTypeNameExcludes, ",") {
			qry.IssueLinkTypeNameExcludes = strings.Split(issueLinkTypeNameExcludes, ",")
		}
	}
	issueLinkStatusExcludes, issueLinkStatusExcludesParamExists := c.GetQuery("issueLinkStatusExcludes")
	if issueLinkStatusExcludesParamExists == true {
		if strings.Contains(issueLinkStatusExcludes, ",") {
			qry.IssueLinkStatusExcludes = strings.Split(issueLinkStatusExcludes, ",")
		}
	}

Discussed in #229

^{Originally posted by mikequentel February 27, 2023}

Is it possible to make the Query Params user interface of Grafana/grafana-csv-datasource accept duplicate keys?

The reason I would like to do this is because I have a web service implemented in Go using Gin that can accept URL parameters that become a list, to populate a struct named Query, where issueLinkTypeNames (for example) can take a list, but this list is typically resolved from URL parameters that are repeated (this appears to be a normal way to do this). This web service successfully returns the CSV when these parameters are passed like this example:

&issueLinkTypeNameExcludes=Relates&issueLinkTypeNameExcludes=Affects

The struct Query that gets populated has some []string fields like this:

package model

type Query struct {
...
	IssueLinkTypeNameExcludes   []string `form:"issueLinkTypeNameExcludes"`
	IssueLinkStatusExcludes     []string `form:"issueLinkStatusExcludes"`
	IssueLinkKeyExcludes        []string `form:"issueLinkKeyExcludes"`
...
}

But the records in Grafana (from grafana-csv-datasource) do not show the expected results because only one of the values of issueLinkTypeNameExcludes is being sent to the web service. This behaviour is definitely happening only through Grafana.

[mikequentel]

Work-around solution of enabling the Query Param to accept a comma-delimited list is satisfactory. Closing this ticket.