[WEB-4054] chore: search-issues endpoint code refactoring (#7029)

* chore: moved some code to seperate function

* fix: function name typo

apiserver/plane/app/views/search/issue.py

@@ -1,5 +1,5 @@
 # Django imports
-from django.db.models import Q
+from django.db.models import Q, QuerySet
 
 # Third party imports
 from rest_framework import status
@@ -12,6 +12,95 @@ from plane.utils.issue_search import search_issues
 
 
 class IssueSearchEndpoint(BaseAPIView):
+    def filter_issues_by_project(self, project_id: int, issues: QuerySet) -> QuerySet:
+        """
+        Filter issues by project
+        """
+
+        issues = issues.filter(project_id=project_id)
+
+        return issues
+
+    def search_issues_by_query(self, query: str, issues: QuerySet) -> QuerySet:
+        """
+        Search issues by query
+        """
+
+        issues = search_issues(query, issues)
+
+        return issues
+
+    def search_issues_and_excluding_parent(
+        self, issues: QuerySet, issue_id: str
+    ) -> QuerySet:
+        """
+        Search issues and epics by query excluding the parent
+        """
+
+        issue = Issue.issue_objects.filter(pk=issue_id).first()
+        if issue:
+            issues = issues.filter(
+                ~Q(pk=issue_id), ~Q(pk=issue.parent_id), ~Q(parent_id=issue_id)
+            )
+        return issues
+
+    def filter_issues_excluding_related_issues(
+        self, issue_id: str, issues: QuerySet
+    ) -> QuerySet:
+        """
+        Filter issues excluding related issues
+        """
+
+        issue = Issue.issue_objects.filter(pk=issue_id).first()
+        related_issue_ids = (
+            IssueRelation.objects.filter(Q(related_issue=issue) | Q(issue=issue))
+            .values_list("issue_id", "related_issue_id")
+            .distinct()
+        )
+
+        related_issue_ids = [item for sublist in related_issue_ids for item in sublist]
+
+        if issue:
+            issues = issues.filter(~Q(pk=issue_id), ~Q(pk__in=related_issue_ids))
+
+        return issues
+
+    def filter_root_issues_only(self, issue_id: str, issues: QuerySet) -> QuerySet:
+        """
+        Filter root issues only
+        """
+        issue = Issue.issue_objects.filter(pk=issue_id).first()
+        if issue:
+            issues = issues.filter(~Q(pk=issue_id), parent__isnull=True)
+        if issue.parent:
+            issues = issues.filter(~Q(pk=issue.parent_id))
+        return issues
+
+    def exclude_issues_in_cycles(self, issues: QuerySet) -> QuerySet:
+        """
+        Exclude issues in cycles
+        """
+        issues = issues.exclude(
+            Q(issue_cycle__isnull=False) & Q(issue_cycle__deleted_at__isnull=True)
+        )
+        return issues
+
+    def exclude_issues_in_module(self, issues: QuerySet, module: str) -> QuerySet:
+        """
+        Exclude issues in a module
+        """
+        issues = issues.exclude(
+            Q(issue_module__module=module) & Q(issue_module__deleted_at__isnull=True)
+        )
+        return issues
+
+    def filter_issues_without_target_date(self, issues: QuerySet) -> QuerySet:
+        """
+        Filter issues without a target date
+        """
+        issues = issues.filter(target_date__isnull=True)
+        return issues
+
     def get(self, request, slug, project_id):
         query = request.query_params.get("search", False)
         workspace_search = request.query_params.get("workspace_search", "false")
@@ -21,7 +110,6 @@ class IssueSearchEndpoint(BaseAPIView):
         module = request.query_params.get("module", False)
         sub_issue = request.query_params.get("sub_issue", "false")
         target_date = request.query_params.get("target_date", True)
-
         issue_id = request.query_params.get("issue_id", False)
 
         issues = Issue.issue_objects.filter(
@@ -32,52 +120,28 @@ class IssueSearchEndpoint(BaseAPIView):
         )
 
         if workspace_search == "false":
-            issues = issues.filter(project_id=project_id)
+            issues = self.filter_issues_by_project(project_id, issues)
 
         if query:
-            issues = search_issues(query, issues)
+            issues = self.search_issues_by_query(query, issues)
 
         if parent == "true" and issue_id:
-            issue = Issue.issue_objects.filter(pk=issue_id).first()
+            issues = self.search_issues_and_excluding_parent(issues, issue_id)
-            if issue:
+
-                issues = issues.filter(
-                    ~Q(pk=issue_id), ~Q(pk=issue.parent_id), ~Q(parent_id=issue_id)
-                )
         if issue_relation == "true" and issue_id:
-            issue = Issue.issue_objects.filter(pk=issue_id).first()
+            issues = self.filter_issues_excluding_related_issues(issue_id, issues)
-            related_issue_ids = IssueRelation.objects.filter(
-                Q(related_issue=issue) | Q(issue=issue)
-            ).values_list(
-                "issue_id", "related_issue_id"
-            ).distinct()
 
-            related_issue_ids = [item for sublist in related_issue_ids for item in sublist]
-
-            if issue:
-                issues = issues.filter(
-                    ~Q(pk=issue_id),
-                    ~Q(pk__in=related_issue_ids),
-                )
         if sub_issue == "true" and issue_id:
-            issue = Issue.issue_objects.filter(pk=issue_id).first()
+            issues = self.filter_root_issues_only(issue_id, issues)
-            if issue:
-                issues = issues.filter(~Q(pk=issue_id), parent__isnull=True)
-            if issue.parent:
-                issues = issues.filter(~Q(pk=issue.parent_id))
 
         if cycle == "true":
-            issues = issues.exclude(
+            issues = self.exclude_issues_in_cycles(issues)
-                Q(issue_cycle__isnull=False) & Q(issue_cycle__deleted_at__isnull=True)
-            )
 
         if module:
-            issues = issues.exclude(
+            issues = self.exclude_issues_in_module(issues, module)
-                Q(issue_module__module=module)
-                & Q(issue_module__deleted_at__isnull=True)
-            )
 
         if target_date == "none":
-            issues = issues.filter(target_date__isnull=True)
+            issues = self.filter_issues_without_target_date(issues)
 
         if ProjectMember.objects.filter(
             project_id=project_id, member=self.request.user, is_active=True, role=5