1 files changed, 150 insertions, 0 deletions

diff --git a/modules/indexer/issues/internal/model.go b/modules/indexer/issues/internal/model.go
new file mode 100644
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--- /dev/null
+++ b/modules/indexer/issues/internal/model.go
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+// Copyright 2023 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package internal
+
+import (
+	"code.gitea.io/gitea/models/db"
+	"code.gitea.io/gitea/modules/optional"
+	"code.gitea.io/gitea/modules/timeutil"
+)
+
+// IndexerData data stored in the issue indexer
+type IndexerData struct {
+	ID       int64 `json:"id"`
+	RepoID   int64 `json:"repo_id"`
+	IsPublic bool  `json:"is_public"` // If the repo is public
+
+	// Fields used for keyword searching
+	Title    string   `json:"title"`
+	Content  string   `json:"content"`
+	Comments []string `json:"comments"`
+
+	// Fields used for filtering
+	IsPull             bool               `json:"is_pull"`
+	IsClosed           bool               `json:"is_closed"`
+	LabelIDs           []int64            `json:"label_ids"`
+	NoLabel            bool               `json:"no_label"` // True if LabelIDs is empty
+	MilestoneID        int64              `json:"milestone_id"`
+	ProjectID          int64              `json:"project_id"`
+	ProjectColumnID    int64              `json:"project_board_id"` // the key should be kept as project_board_id to keep compatible
+	PosterID           int64              `json:"poster_id"`
+	AssigneeID         int64              `json:"assignee_id"`
+	MentionIDs         []int64            `json:"mention_ids"`
+	ReviewedIDs        []int64            `json:"reviewed_ids"`
+	ReviewRequestedIDs []int64            `json:"review_requested_ids"`
+	SubscriberIDs      []int64            `json:"subscriber_ids"`
+	UpdatedUnix        timeutil.TimeStamp `json:"updated_unix"`
+
+	// Fields used for sorting
+	// UpdatedUnix is both used for filtering and sorting.
+	// ID is used for sorting too, to make the sorting stable.
+	CreatedUnix  timeutil.TimeStamp `json:"created_unix"`
+	DeadlineUnix timeutil.TimeStamp `json:"deadline_unix"`
+	CommentCount int64              `json:"comment_count"`
+}
+
+// Match represents on search result
+type Match struct {
+	ID    int64   `json:"id"`
+	Score float64 `json:"score"`
+}
+
+// SearchResult represents search results
+type SearchResult struct {
+	Total int64
+	Hits  []Match
+}
+
+// SearchOptions represents search options.
+//
+// It has a slightly different design from database query options.
+// In database query options, a field is never a pointer, so it could be confusing when it's zero value:
+// Do you want to find data with a field value of 0, or do you not specify the field in the options?
+// To avoid this confusion, db introduced db.NoConditionID(-1).
+// So zero value means the field is not specified in the search options, and db.NoConditionID means "== 0" or "id NOT IN (SELECT id FROM ...)"
+// It's still not ideal, it trapped developers many times.
+// And sometimes -1 could be a valid value, like issue ID, negative numbers indicate exclusion.
+// Since db.NoConditionID is for "db" (the package name is db), it makes sense not to use it in the indexer:
+// Why do bleve/elasticsearch/meilisearch indexers need to know about db.NoConditionID?
+// So in SearchOptions, we use pointer for fields which could be not specified,
+// and always use the value to filter if it's not nil, even if it's zero or negative.
+// It can handle almost all cases, if there is an exception, we can add a new field, like NoLabelOnly.
+// Unfortunately, we still use db for the indexer and have to convert between db.NoConditionID and nil for legacy reasons.
+type SearchOptions struct {
+	Keyword string // keyword to search
+
+	IsFuzzyKeyword bool // if false the levenshtein distance is 0
+
+	RepoIDs   []int64 // repository IDs which the issues belong to
+	AllPublic bool    // if include all public repositories
+
+	IsPull   optional.Option[bool] // if the issues is a pull request
+	IsClosed optional.Option[bool] // if the issues is closed
+
+	IncludedLabelIDs    []int64 // labels the issues have
+	ExcludedLabelIDs    []int64 // labels the issues don't have
+	IncludedAnyLabelIDs []int64 // labels the issues have at least one. It will be ignored if IncludedLabelIDs is not empty. It's an uncommon filter, but it has been supported accidentally by issues.IssuesOptions.IncludedLabelNames.
+	NoLabelOnly         bool    // if the issues have no label, if true, IncludedLabelIDs and ExcludedLabelIDs, IncludedAnyLabelIDs will be ignored
+
+	MilestoneIDs []int64 // milestones the issues have
+
+	ProjectID       optional.Option[int64] // project the issues belong to
+	ProjectColumnID optional.Option[int64] // project column the issues belong to
+
+	PosterID optional.Option[int64] // poster of the issues
+
+	AssigneeID optional.Option[int64] // assignee of the issues, zero means no assignee
+
+	MentionID optional.Option[int64] // mentioned user of the issues
+
+	ReviewedID        optional.Option[int64] // reviewer of the issues
+	ReviewRequestedID optional.Option[int64] // requested reviewer of the issues
+
+	SubscriberID optional.Option[int64] // subscriber of the issues
+
+	UpdatedAfterUnix  optional.Option[int64]
+	UpdatedBeforeUnix optional.Option[int64]
+
+	Paginator *db.ListOptions
+
+	SortBy SortBy // sort by field
+}
+
+// Copy returns a copy of the options.
+// Be careful, it's not a deep copy, so `SearchOptions.RepoIDs = {...}` is OK while `SearchOptions.RepoIDs[0] = ...` is not.
+func (o *SearchOptions) Copy(edit ...func(options *SearchOptions)) *SearchOptions {
+	if o == nil {
+		return nil
+	}
+	v := *o
+	for _, e := range edit {
+		e(&v)
+	}
+	return &v
+}
+
+type SortBy string
+
+const (
+	SortByCreatedDesc  SortBy = "-created_unix"
+	SortByUpdatedDesc  SortBy = "-updated_unix"
+	SortByCommentsDesc SortBy = "-comment_count"
+	SortByDeadlineDesc SortBy = "-deadline_unix"
+	SortByCreatedAsc   SortBy = "created_unix"
+	SortByUpdatedAsc   SortBy = "updated_unix"
+	SortByCommentsAsc  SortBy = "comment_count"
+	SortByDeadlineAsc  SortBy = "deadline_unix"
+	// Unsupported sort types which are supported by issues.IssuesOptions.SortType:
+	//
+	//  - "priorityrepo":
+	//                    It's impossible to support it in the indexer.
+	//                    It is based on the specified repository in the request, so we cannot add static field to the indexer.
+	//                    If we do something like that query the issues in the specified repository first then append other issues,
+	//                    it will break the pagination.
+	//
+	// - "project-column-sorting":
+	//                    Although it's possible to support it by adding project.ProjectIssue.Sorting to the indexer,
+	//                    but what if the issue belongs to multiple projects?
+	//                    Since it's unsupported to search issues with keyword in project page, we don't need to support it.
+)