feat: Implement Transfer Rules Engine for Cross-Repository Issue Routing (#22)

* feat: Create new development session and set as current.

* feat: Implement GitHub issue transfer functionality with rule-based matching and GraphQL API integration.

* feat: Enhance `TransferIssue` to return the new issue URL and improve GraphQL client validation, which is then used by the action executor.

* Update internal/transfer/matcher.go

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

* fix: address code review feedback

- Add whitespace trimming for targetRepo input validation
- Truncate error response bodies to prevent sensitive data leaks
- Add empty URL validation after transfer completion
- Fix Transfer config merge logic to allow child to disable parent

---------

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

Author: Kavirubc

.claude/sessions/.current-session

@@ -0,0 +1 @@
+2026-02-04-0000.md

.claude/sessions/2026-02-04-0000.md

@@ -0,0 +1,20 @@
+# Development Session - 2026-02-04 00:00
+
+## Session Overview
+- **Start Time**: 2026-02-04 00:00
+- **Status**: Active
+
+## Goals
+- Develop and implement new features for simili-bot
+
+## Progress
+
+### Tasks Completed
+- Session started
+
+### Current Work
+- Ready to begin feature development
+
+### Notes
+-
+

internal/core/config/config.go

@@ -37,6 +37,9 @@ type Config struct {
 
 	// Repositories lists the repositories this config applies to.
 	Repositories []RepositoryConfig `yaml:"repositories,omitempty"`
+
+	// Transfer configures cross-repository issue routing.
+	Transfer TransferConfig `yaml:"transfer,omitempty"`
 }
 
 // QdrantConfig holds Qdrant connection settings.
@@ -69,6 +72,25 @@ type RepositoryConfig struct {
 	Enabled bool     `yaml:"enabled"`
 }
 
+// TransferRule defines a rule for transferring issues to another repository.
+type TransferRule struct {
+	Name          string   `yaml:"name"`
+	Priority      int      `yaml:"priority,omitempty"`
+	Target        string   `yaml:"target"`                 // "owner/repo"
+	Labels        []string `yaml:"labels,omitempty"`       // ALL must match
+	LabelsAny     []string `yaml:"labels_any,omitempty"`   // ANY must match
+	TitleContains []string `yaml:"title_contains,omitempty"`
+	BodyContains  []string `yaml:"body_contains,omitempty"`
+	Author        []string `yaml:"author,omitempty"`
+	Enabled       *bool    `yaml:"enabled,omitempty"`
+}
+
+// TransferConfig holds transfer routing settings.
+type TransferConfig struct {
+	Enabled bool           `yaml:"enabled"`
+	Rules   []TransferRule `yaml:"rules,omitempty"`
+}
+
 // Load reads a config file from the given path and expands environment variables.
 func Load(path string) (*Config, error) {
 	data, err := os.ReadFile(path)
@@ -214,6 +236,13 @@ func mergeConfigs(parent, child *Config) *Config {
 		result.Repositories = child.Repositories
 	}
 
+	// Transfer.Enabled: always take the child value so it can override parent true -> false and vice versa
+	result.Transfer.Enabled = child.Transfer.Enabled
+	// Transfer.Rules: child overrides rules if non-empty; otherwise inherit from parent
+	if len(child.Transfer.Rules) > 0 {
+		result.Transfer.Rules = child.Transfer.Rules
+	}
+
 	return &result
 }
 

internal/core/pipeline/registry.go

@@ -113,8 +113,8 @@ var Presets = map[string][]string{
 	"issue-triage": {
 		"gatekeeper",
 		"vectordb_prep",
-		"similarity_search",
 		"transfer_check",
+		"similarity_search",
 		"triage",
 		"response_builder",
 		"action_executor",

internal/integrations/github/auth.go

@@ -17,17 +17,21 @@ import (
 // If token is empty, it returns an unauthenticated client.
 func NewClient(ctx context.Context, token string) *Client {
 	var tc *http.Client
+	var graphql *GraphQLClient
 
 	if token != "" {
 		ts := oauth2.StaticTokenSource(
 			&oauth2.Token{AccessToken: token},
 		)
 		tc = oauth2.NewClient(ctx, ts)
+		// Initialize GraphQL client for authenticated operations
+		graphql = NewGraphQLClient(tc, token)
 	}
 
 	client := github.NewClient(tc)
 
 	return &Client{
-		client: client,
+		client:  client,
+		graphql: graphql,
 	}
 }

internal/integrations/github/client.go

@@ -15,7 +15,8 @@ import (
 
 // Client wraps the GitHub API client.
 type Client struct {
-	client *github.Client
+	client  *github.Client
+	graphql *GraphQLClient
 }
 
 // GetIssue fetches issue details.
@@ -57,25 +58,49 @@ func (c *Client) AddLabels(ctx context.Context, org, repo string, number int, la
 	return nil
 }
 
-// TransferIssue transfers an issue to another repository.
-// Note: Transferring issues via API requires the user to have admin access.
+// TransferIssue transfers an issue to another repository using GitHub GraphQL API.
+// Requires the user to have admin/write access to both repositories.
 // targetRepo should be in "owner/repo" format.
-//
-// TODO: GitHub's REST API for issue transfers is complex and may require GraphQL.
-// This is not yet implemented. See https://docs.github.com/en/graphql/reference/mutations#transferissue
-func (c *Client) TransferIssue(ctx context.Context, org, repo string, number int, targetRepo string) error {
+// Returns the URL of the transferred issue.
+func (c *Client) TransferIssue(ctx context.Context, org, repo string, number int, targetRepo string) (string, error) {
+	// Trim whitespace from input
+	targetRepo = strings.TrimSpace(targetRepo)
+
 	// Validate input format
 	parts := strings.Split(targetRepo, "/")
 	if len(parts) != 2 {
-		return fmt.Errorf("invalid targetRepo format: expected 'owner/repo', got '%s'", targetRepo)
+		return "", fmt.Errorf("invalid targetRepo format: expected 'owner/repo', got '%s'", targetRepo)
+	}
+
+	targetOwner, targetRepoName := strings.TrimSpace(parts[0]), strings.TrimSpace(parts[1])
+	if targetOwner == "" || targetRepoName == "" {
+		return "", fmt.Errorf("invalid targetRepo: owner and repo cannot be empty")
+	}
+
+	// Check if GraphQL client is available
+	if c.graphql == nil {
+		return "", fmt.Errorf("issue transfer requires authenticated GraphQL client")
+	}
+
+	// Get issue node ID
+	issueNodeID, err := c.graphql.GetIssueNodeID(ctx, org, repo, number)
+	if err != nil {
+		return "", fmt.Errorf("failed to get issue node ID: %w", err)
+	}
+
+	// Get target repository node ID
+	targetRepoNodeID, err := c.graphql.GetRepositoryNodeID(ctx, targetOwner, targetRepoName)
+	if err != nil {
+		return "", fmt.Errorf("failed to get target repository node ID: %w", err)
 	}
 
-	if parts[0] == "" || parts[1] == "" {
-		return fmt.Errorf("invalid targetRepo: owner and repo cannot be empty")
+	// Execute transfer
+	newURL, err := c.graphql.TransferIssue(ctx, issueNodeID, targetRepoNodeID)
+	if err != nil {
+		return "", fmt.Errorf("failed to transfer issue: %w", err)
 	}
 
-	// Transfer API is not implemented yet
-	return fmt.Errorf("issue transfer not yet implemented - requires GraphQL API integration")
+	return newURL, nil
 }
 
 // ListIssues fetches a list of issues from the repository.

internal/integrations/github/client_test.go

@@ -41,7 +41,7 @@ func TestAddLabelsValidation(t *testing.T) {
 }
 
 func TestTransferIssueValidation(t *testing.T) {
-	client := &Client{client: nil} // nil client for validation testing
+	client := &Client{client: nil, graphql: nil} // nil client for validation testing
 
 	tests := []struct {
 		name       string
@@ -58,14 +58,13 @@ func TestTransferIssueValidation(t *testing.T) {
 
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
-			err := client.TransferIssue(context.Background(), "org", "repo", 1, tt.targetRepo)
+			_, err := client.TransferIssue(context.Background(), "org", "repo", 1, tt.targetRepo)
 			if tt.shouldFail && err == nil {
 				t.Errorf("Expected error for targetRepo=%q", tt.targetRepo)
 			}
-			// Note: All cases should fail with "not yet implemented" but we're testing
-			// that validation errors come first for invalid formats
-			if !tt.shouldFail && err != nil && err.Error() != "issue transfer not yet implemented - requires GraphQL API integration" {
-				t.Errorf("Expected 'not yet implemented' error, got: %v", err)
+			// Valid format but no graphql client should fail with "requires authenticated GraphQL client"
+			if !tt.shouldFail && err != nil && err.Error() != "issue transfer requires authenticated GraphQL client" {
+				t.Errorf("Expected 'requires authenticated GraphQL client' error, got: %v", err)
 			}
 		})
 	}