承認履歴情報周りの取得方法サンプルクエリ

getProcessInstanceInfo.cls

ProcessInstance p = [
    SELECT
         Id
        ,CompletedDate
        ,LastActorId
        ,ProcessDefinitionId
        ,Status
        ,TargetObjectId
        ,(SELECT Id,ActorId,Comments,IsPending,OriginalActorId,ProcessInstanceId,ProcessNodeId,StepStatus,TargetObjectId FROM StepsAndWorkitems)
    FROM
        ProcessInstance
    LIMIT 1
];
// ProcessInstanceの確認
System.debug('-- ProcessInstance --');
System.debug(p);
// ProcessInstanceHistoryの確認
System.debug('-- ProcessInstanceHistory --');
for (ProcessInstanceHistory sw : p.StepsAndWorkitems) {
    System.debug(sw);
}
// ProcessNodeId取得
Set<String> nodeIds = new Set<String>();
for (ProcessInstanceHistory sw : p.StepsAndWorkitems) {
    nodeIds.add(sw.ProcessNodeId);
}
List<ProcessInstanceNode> processNodes = [
    SELECT
         Id
        ,CompletedDate
        ,LastActorId
        ,NodeStatus
        ,ProcessInstanceId
        ,ProcessNodeId
        ,ProcessNodeName
    FROM
        ProcessInstanceNode
    WHERE
        ProcessNodeId IN: nodeIds
];
System.debug('-- ProcessInstanceNode --');
System.debug(processNodes);

// 参考サイト
// https://developer.salesforce.com/docs/atlas.ja-jp.198.0.object_reference.meta/object_reference/sforce_api_objects_processinstance.htm?search_text=ProcessInstance