Implement Category API methods (GetAllCategories, GetCategory)

- GetAllCategories returns all categories for a project
- GetCategory returns a single category by ID
- Returns ErrCategoryNotFound for non-existent categories
- Added ErrCategoryNotFound to IsNotFound helper
- Comprehensive test coverage

.beads/issues.jsonl

@@ -1,4 +1,4 @@
-{"id":"kanboard-api-0fz","title":"Implement Category API methods","description":"Implement direct API methods for category operations.\n\n## Methods to implement\n- GetAllCategories(ctx, projectID int) ([]Category, error) - getAllCategories\n- GetCategory(ctx, categoryID int) (*Category, error) - getCategory (Nice-to-have)\n\n## Files to create\n- categories.go\n\n## Acceptance criteria\n- Proper error handling\n- Returns empty slice when no categories exist","status":"open","priority":1,"issue_type":"feature","owner":"mail@oliverjakoubek.de","created_at":"2026-01-15T17:35:16.6133153+01:00","created_by":"Oliver Jakoubek","updated_at":"2026-01-15T17:35:16.6133153+01:00","dependencies":[{"issue_id":"kanboard-api-0fz","depends_on_id":"kanboard-api-uls","type":"blocks","created_at":"2026-01-15T17:42:53.161416595+01:00","created_by":"Oliver Jakoubek"},{"issue_id":"kanboard-api-0fz","depends_on_id":"kanboard-api-cyc","type":"blocks","created_at":"2026-01-15T17:42:53.226963473+01:00","created_by":"Oliver Jakoubek"}]}
+{"id":"kanboard-api-0fz","title":"Implement Category API methods","description":"Implement direct API methods for category operations.\n\n## Methods to implement\n- GetAllCategories(ctx, projectID int) ([]Category, error) - getAllCategories\n- GetCategory(ctx, categoryID int) (*Category, error) - getCategory (Nice-to-have)\n\n## Files to create\n- categories.go\n\n## Acceptance criteria\n- Proper error handling\n- Returns empty slice when no categories exist","status":"closed","priority":1,"issue_type":"feature","owner":"mail@oliverjakoubek.de","created_at":"2026-01-15T17:35:16.6133153+01:00","created_by":"Oliver Jakoubek","updated_at":"2026-01-15T18:25:07.250066801+01:00","closed_at":"2026-01-15T18:25:07.250066801+01:00","close_reason":"Closed","dependencies":[{"issue_id":"kanboard-api-0fz","depends_on_id":"kanboard-api-uls","type":"blocks","created_at":"2026-01-15T17:42:53.161416595+01:00","created_by":"Oliver Jakoubek"},{"issue_id":"kanboard-api-0fz","depends_on_id":"kanboard-api-cyc","type":"blocks","created_at":"2026-01-15T17:42:53.226963473+01:00","created_by":"Oliver Jakoubek"}]}
 {"id":"kanboard-api-16r","title":"Implement Tag API methods (CRITICAL)","description":"Implement direct API methods for tag operations. Tags are CRITICAL - heavily used.\n\n## Direct Client methods (Must-have)\n- GetTaskTags(ctx, taskID int) (map[int]string, error) - getTaskTags\n- SetTaskTags(ctx, projectID, taskID int, tags []string) error - setTaskTags\n\n## Direct Client methods (Nice-to-have)\n- GetAllTags(ctx) ([]Tag, error) - getAllTags\n- GetTagsByProject(ctx, projectID int) ([]Tag, error) - getTagsByProject\n- CreateTag(ctx, projectID int, name, colorID string) (int, error) - createTag\n- UpdateTag(ctx, tagID int, name, colorID string) error - updateTag\n- RemoveTag(ctx, tagID int) error - removeTag\n\n## Files to create\n- tags.go\n\n## IMPORTANT NOTE\nsetTaskTags REPLACES ALL tags. Individual add/remove requires read-modify-write pattern (implemented in TaskScope).\n\n## Acceptance criteria\n- GetTaskTags returns map[tagID]tagName\n- SetTaskTags accepts tag names (auto-creates if needed)","status":"closed","priority":0,"issue_type":"feature","owner":"mail@oliverjakoubek.de","created_at":"2026-01-15T17:36:08.526810135+01:00","created_by":"Oliver Jakoubek","updated_at":"2026-01-15T18:20:17.392248254+01:00","closed_at":"2026-01-15T18:20:17.392248254+01:00","close_reason":"Closed","dependencies":[{"issue_id":"kanboard-api-16r","depends_on_id":"kanboard-api-uls","type":"blocks","created_at":"2026-01-15T17:43:49.223137796+01:00","created_by":"Oliver Jakoubek"},{"issue_id":"kanboard-api-16r","depends_on_id":"kanboard-api-cyc","type":"blocks","created_at":"2026-01-15T17:43:49.402237867+01:00","created_by":"Oliver Jakoubek"}]}
 {"id":"kanboard-api-25y","title":"Implement Timestamp type with JSON handling","description":"Implement custom Timestamp type that handles Kanboard's Unix timestamp format.\n\n## Requirements\n- Timestamp struct wrapping time.Time\n- UnmarshalJSON supporting:\n  - Unix timestamps as integers\n  - Empty strings and \"0\" as zero time\n  - Zero value (0) as zero time\n- MarshalJSON returning Unix timestamp or 0 for zero time\n\n## Files to create\n- timestamp.go\n\n## Acceptance criteria\n- Correctly parses integer Unix timestamps\n- Handles empty strings and \"0\" strings\n- Zero time marshals to 0\n- Non-zero time marshals to Unix timestamp","status":"closed","priority":0,"issue_type":"feature","owner":"mail@oliverjakoubek.de","created_at":"2026-01-15T17:34:55.0044989+01:00","created_by":"Oliver Jakoubek","updated_at":"2026-01-15T18:15:27.299644047+01:00","closed_at":"2026-01-15T18:15:27.299644047+01:00","close_reason":"Closed"}
 {"id":"kanboard-api-2g1","title":"Implement JSON-RPC client foundation","description":"Implement the core JSON-RPC 2.0 client for Kanboard API communication.\n\n## Requirements\n- JSONRPCRequest struct with jsonrpc, method, id, params fields\n- JSONRPCResponse struct with jsonrpc, id, result, error fields  \n- JSONRPCError struct with code and message\n- Generic `call` method to send requests and parse responses\n- Automatic `/jsonrpc.php` path appending to baseURL\n- Thread-safe request ID generation via atomic.Int64\n\n## Files to create\n- jsonrpc.go\n\n## Acceptance criteria\n- All JSON-RPC structs properly marshal/unmarshal\n- Request IDs increment atomically\n- Supports subdirectory installations (e.g. /kanboard/jsonrpc.php)","status":"closed","priority":0,"issue_type":"feature","owner":"mail@oliverjakoubek.de","created_at":"2026-01-15T17:34:53.232007312+01:00","created_by":"Oliver Jakoubek","updated_at":"2026-01-15T18:10:29.68466887+01:00","closed_at":"2026-01-15T18:10:29.68466887+01:00","close_reason":"Closed"}

categories.go

@@ -0,0 +1,35 @@
+package kanboard
+
+import (
+	"context"
+	"fmt"
+)
+
+// GetAllCategories returns all categories for a project.
+func (c *Client) GetAllCategories(ctx context.Context, projectID int) ([]Category, error) {
+	params := map[string]int{"project_id": projectID}
+
+	var result []Category
+	if err := c.call(ctx, "getAllCategories", params, &result); err != nil {
+		return nil, fmt.Errorf("getAllCategories: %w", err)
+	}
+
+	return result, nil
+}
+
+// GetCategory returns a category by its ID.
+// Returns ErrCategoryNotFound if the category does not exist.
+func (c *Client) GetCategory(ctx context.Context, categoryID int) (*Category, error) {
+	params := map[string]int{"category_id": categoryID}
+
+	var result *Category
+	if err := c.call(ctx, "getCategory", params, &result); err != nil {
+		return nil, fmt.Errorf("getCategory: %w", err)
+	}
+
+	if result == nil {
+		return nil, fmt.Errorf("%w: category %d", ErrCategoryNotFound, categoryID)
+	}
+
+	return result, nil
+}

categories_test.go

@@ -0,0 +1,166 @@
+package kanboard
+
+import (
+	"context"
+	"encoding/json"
+	"errors"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+)
+
+func TestClient_GetAllCategories(t *testing.T) {
+	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		var req JSONRPCRequest
+		json.NewDecoder(r.Body).Decode(&req)
+
+		if req.Method != "getAllCategories" {
+			t.Errorf("expected method=getAllCategories, got %s", req.Method)
+		}
+
+		params := req.Params.(map[string]any)
+		if params["project_id"].(float64) != 1 {
+			t.Errorf("expected project_id=1, got %v", params["project_id"])
+		}
+
+		resp := JSONRPCResponse{
+			JSONRPC: "2.0",
+			ID:      req.ID,
+			Result: json.RawMessage(`[
+				{"id": "1", "name": "Bug", "project_id": "1", "color_id": "red"},
+				{"id": "2", "name": "Feature", "project_id": "1", "color_id": "blue"}
+			]`),
+		}
+		json.NewEncoder(w).Encode(resp)
+	}))
+	defer server.Close()
+
+	client := NewClient(server.URL).WithAPIToken("test-token")
+
+	categories, err := client.GetAllCategories(context.Background(), 1)
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+
+	if len(categories) != 2 {
+		t.Errorf("expected 2 categories, got %d", len(categories))
+	}
+
+	if categories[0].Name != "Bug" {
+		t.Errorf("expected first category='Bug', got %s", categories[0].Name)
+	}
+	if categories[1].Name != "Feature" {
+		t.Errorf("expected second category='Feature', got %s", categories[1].Name)
+	}
+}
+
+func TestClient_GetAllCategories_Empty(t *testing.T) {
+	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		var req JSONRPCRequest
+		json.NewDecoder(r.Body).Decode(&req)
+
+		resp := JSONRPCResponse{
+			JSONRPC: "2.0",
+			ID:      req.ID,
+			Result:  json.RawMessage(`[]`),
+		}
+		json.NewEncoder(w).Encode(resp)
+	}))
+	defer server.Close()
+
+	client := NewClient(server.URL).WithAPIToken("test-token")
+
+	categories, err := client.GetAllCategories(context.Background(), 1)
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+
+	if len(categories) != 0 {
+		t.Errorf("expected 0 categories, got %d", len(categories))
+	}
+}
+
+func TestClient_GetCategory(t *testing.T) {
+	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		var req JSONRPCRequest
+		json.NewDecoder(r.Body).Decode(&req)
+
+		if req.Method != "getCategory" {
+			t.Errorf("expected method=getCategory, got %s", req.Method)
+		}
+
+		params := req.Params.(map[string]any)
+		if params["category_id"].(float64) != 5 {
+			t.Errorf("expected category_id=5, got %v", params["category_id"])
+		}
+
+		resp := JSONRPCResponse{
+			JSONRPC: "2.0",
+			ID:      req.ID,
+			Result:  json.RawMessage(`{"id": "5", "name": "Bug", "project_id": "1", "color_id": "red"}`),
+		}
+		json.NewEncoder(w).Encode(resp)
+	}))
+	defer server.Close()
+
+	client := NewClient(server.URL).WithAPIToken("test-token")
+
+	category, err := client.GetCategory(context.Background(), 5)
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+
+	if int(category.ID) != 5 {
+		t.Errorf("expected ID=5, got %d", category.ID)
+	}
+	if category.Name != "Bug" {
+		t.Errorf("expected name='Bug', got %s", category.Name)
+	}
+	if category.ColorID != "red" {
+		t.Errorf("expected color_id='red', got %s", category.ColorID)
+	}
+}
+
+func TestClient_GetCategory_NotFound(t *testing.T) {
+	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		var req JSONRPCRequest
+		json.NewDecoder(r.Body).Decode(&req)
+
+		// Kanboard returns null for non-existent categories
+		resp := JSONRPCResponse{
+			JSONRPC: "2.0",
+			ID:      req.ID,
+			Result:  json.RawMessage(`null`),
+		}
+		json.NewEncoder(w).Encode(resp)
+	}))
+	defer server.Close()
+
+	client := NewClient(server.URL).WithAPIToken("test-token")
+
+	_, err := client.GetCategory(context.Background(), 999)
+	if err == nil {
+		t.Fatal("expected error for non-existent category")
+	}
+
+	if !errors.Is(err, ErrCategoryNotFound) {
+		t.Errorf("expected ErrCategoryNotFound, got %v", err)
+	}
+}
+
+func TestClient_GetAllCategories_ContextCanceled(t *testing.T) {
+	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		select {}
+	}))
+	defer server.Close()
+
+	client := NewClient(server.URL).WithAPIToken("test-token")
+
+	ctx, cancel := context.WithCancel(context.Background())
+	cancel()
+
+	_, err := client.GetAllCategories(ctx, 1)
+	if err == nil {
+		t.Fatal("expected error due to canceled context")
+	}
+}

errors.go

@@ -39,6 +39,9 @@ var (
 
 	// ErrCommentNotFound indicates the specified comment was not found.
 	ErrCommentNotFound = errors.New("comment not found")
+
+	// ErrCategoryNotFound indicates the specified category was not found.
+	ErrCategoryNotFound = errors.New("category not found")
 )
 
 // Logic errors
@@ -82,7 +85,8 @@ func IsNotFound(err error) bool {
 		errors.Is(err, ErrProjectNotFound) ||
 		errors.Is(err, ErrTaskNotFound) ||
 		errors.Is(err, ErrColumnNotFound) ||
-		errors.Is(err, ErrCommentNotFound)
+		errors.Is(err, ErrCommentNotFound) ||
+		errors.Is(err, ErrCategoryNotFound)
 }
 
 // IsUnauthorized returns true if the error indicates an authentication failure.