Server side pagination in Graphql Scala - mysql

Question

I need to do server side pagination in graphql in scala. I have seven reports and have used one graphql query with different operations to get the data. Now I need to add server side pagination to it and I am not able to do that. Any help would be appreciated. Below are my code:
Schema:
val PanelNominationStatusReportDataType = ObjectType(
"PanelNominationStatus",
"Dashboard Reports",
fields[Unit, PanelRewardSatusDetail](
Field("awardName", OptionType(StringType), resolve = _.value.awardName),
Field("nominatorEmail", OptionType(StringType), resolve = _.value.nominatorEmail),
Field("nomineeEmail", OptionType(StringType), resolve = _.value.nomineeEmail),
Field("nomineeLocation", OptionType(StringType), resolve = _.value.nomineeLocation),
Field("approverEmail", OptionType(StringType), resolve = _.value.approverEmail),
Field("citation", OptionType(StringType), resolve = _.value.citation),
Field("businessJustification", OptionType(StringType), resolve = _.value.businessJustification),
Field("rating", OptionType(IntType), resolve = _.value.rating),
Field("votingStatus", OptionType(StringType), resolve = _.value.votingStatus),
Field("nominatedDate", OptionType(StringType), resolve = _.value.nominatedDate),
Field("approvedDate", OptionType(StringType), resolve = _.value.approvedDate)
)
)
Graphql Query:
Field(
"PanelNominationStatus",
ListType(PanelNominationStatusReportDataType),
description = Some("Returns the Employee Reward Report Data"),
arguments = companyIdType :: rewardNamesType :: startDateType :: endDateType :: Nil,
resolve = { c =>
c.ctx.getPanelStatusReport(c.arg(companyIdType), c.arg(startDateType), c.arg(endDateType), c.arg(rewardNamesType))
})
DataRepo:
def getPanelStatusReport(companyId: Int, startDate: Long, endDate: Long, rewardNames: Seq[String]): List[PanelRewardSatusDetail] = {
val redemptionReport = Await.result(reportsModel.findPanelRewardStatusDetailsReport(companyId, rewardNames, startDate, endDate), 20.seconds).toList
redemptionReport
}
And at last the model:
def findPanelRewardStatusDetailsReport(companyId: Int, rewardNames: Seq[String], startDate: Long, endDate: Long): Future[Seq[PanelRewardSatusDetail]] = {
val df = new SimpleDateFormat("dd-MM-yyyy")
val start = stringToDateTime(df.format(startDate * 1000L), None).toDateTime()
val end = stringToDateTime(df.format(endDate * 1000L), None).toDateTime()
val rewardFilter = if(rewardNames.nonEmpty) "AND vrrc.reward_name IN (" + rewardNames.map(a => "'" + a + "'").mkString(",") + ")" else ""
implicit val getOrdersResult = GetResult(r => PanelRewardSatusDetail(r.<<, r.<<, r.<<, r.<<, r.<<, r.<<, r.<<, r.<<, r.<<, r.<<, r.<<))
val q = sql"""select vrrc.reward_name, (select login from users where id=vrur.sender_id), (select login from users where id=vrur.receiver_ids), (select city_name from cities where id=(select city_id from users where id=vrur.receiver_ids)), (select login from users where id=approver_user_id), vrur.comment, vrur.business_justification, vrpa.rating, CASE WHEN vrpa.is_approved = 1 THEN 'VOTED' ELSE 'NOT VOTED' END, date(vrpa.created_at), date(vrpa.approved_at) from vr_panel_approval vrpa inner join vr_user_reward vrur on vrur.id=vrpa.user_reward_id inner join vr_reward_config vrrc on vrrc.id=vrur.reward_config_id where vrrc.company_id = $companyId and date(vrpa.created_at) between date($start) and date($end) #$rewardFilter"""
db.run(q.as[PanelRewardSatusDetail])
}
My request query:
{
"query": "query PanelNominationStatus($startDate: Long!, $endDate: Long!, $companyId: Int!, $rewardNames: [String!]!) { PanelNominationStatus( startDate: $startDate, endDate: $endDate, companyId: $companyId, rewardNames: $rewardNames ) { awardName nominatorEmail nomineeEmail nomineeLocation approverEmail citation businessJustification rating votingStatus nominatedDate approvedDate }}",
"operationName": "PanelNominationStatus",
"variables": {
"startDate": 1285891200,
"endDate": 1576108800,
"companyId": 355,
"rewardNames": ["PANEL AWARD FEBRUARY", "PANEL AWARD MARCH"]
}
}
I can make it possible using limit in the query and accepting it in the query but I need to send the total count of rows in the response as well. But I am not able to figure out where to make change in schema.

Answer 1

You just need to define another GraphQL type for your result which also contains the count,
val PanelNominationStatusResultType = ObjectType(
"PanelNominationStatusResult",
"Dashboard Reports",
fields[Unit, List[PanelRewardSatusDetail]](
Field(
"count",
IntType,
description = Some("count of nomination-status-reports in this response"),
resolve = _.value.length
),
Field(
"panelNominationStatusList",
ListType(PanelNominationStatusReportDataType),
description = Some("list of nomination-status-reports"),
resolve = _.value
)
)
)
Now, as for your query,
Field(
"panelNominationStatusResult",
PanelNominationStatusResultType,
description = Some("Returns the details of ............"),
arguments = companyIdType :: rewardNamesType :: startDateType :: endDateType :: Nil,
resolve = { c =>
c.ctx.getPanelStatusReport(c.arg(companyIdType), c.arg(startDateType), c.arg(endDateType), c.arg(rewardNamesType))
}
)
If you want the totalCount, then first of all you need to change your getPanelStatusReport method to also return the totalCount
def findPanelRewardStatusDetailsReport(
companyId: Int,
rewardNames: Seq[String],
startDate: Long,
endDate: Long
): Future[(Int, Seq[PanelRewardSatusDetail])] = ???
// updated result type
val PanelNominationStatusResultType = ObjectType(
"PanelNominationStatusResult",
"Dashboard Reports",
fields[Unit, (Int, List[PanelRewardSatusDetail])](
Field(
"totalCount",
IntType,
description = Some("total count of nomination-status-reports"),
resolve = _.value._1
),
Field(
"count",
IntType,
description = Some("count of nomination-status-reports in this response"),
resolve = _.value._2.length
),
Field(
"panelNominationStatusList",
ListType(PanelNominationStatusReportDataType),
description = Some("list of nomination-status-reports"),
resolve = _.value._2
)
)
)