feat: Add support for Canvas API methods (#1334)

This PR introduces new functionalities for managing canvases and
creating channel-specific canvases.

- CreateCanvas
- DeleteCanvas
- EditCanvas
- SetCanvasAccess
- DeleteCanvasAccess
- LookupCanvasSections
- CreateChannelCanvas

Closes #1333

canvas.go

@@ -0,0 +1,264 @@
+package slack
+
+import (
+	"context"
+	"encoding/json"
+	"net/url"
+)
+
+type CanvasDetails struct {
+	CanvasID string `json:"canvas_id"`
+}
+
+type DocumentContent struct {
+	Type     string `json:"type"`
+	Markdown string `json:"markdown,omitempty"`
+}
+
+type CanvasChange struct {
+	Operation       string          `json:"operation"`
+	SectionID       string          `json:"section_id,omitempty"`
+	DocumentContent DocumentContent `json:"document_content"`
+}
+
+type EditCanvasParams struct {
+	CanvasID string         `json:"canvas_id"`
+	Changes  []CanvasChange `json:"changes"`
+}
+
+type SetCanvasAccessParams struct {
+	CanvasID    string   `json:"canvas_id"`
+	AccessLevel string   `json:"access_level"`
+	ChannelIDs  []string `json:"channel_ids,omitempty"`
+	UserIDs     []string `json:"user_ids,omitempty"`
+}
+
+type DeleteCanvasAccessParams struct {
+	CanvasID   string   `json:"canvas_id"`
+	ChannelIDs []string `json:"channel_ids,omitempty"`
+	UserIDs    []string `json:"user_ids,omitempty"`
+}
+
+type LookupCanvasSectionsCriteria struct {
+	SectionTypes []string `json:"section_types,omitempty"`
+	ContainsText string   `json:"contains_text,omitempty"`
+}
+
+type LookupCanvasSectionsParams struct {
+	CanvasID string                       `json:"canvas_id"`
+	Criteria LookupCanvasSectionsCriteria `json:"criteria"`
+}
+
+type CanvasSection struct {
+	ID string `json:"id"`
+}
+
+type LookupCanvasSectionsResponse struct {
+	SlackResponse
+	Sections []CanvasSection `json:"sections"`
+}
+
+// CreateCanvas creates a new canvas.
+// For more details, see CreateCanvasContext documentation.
+func (api *Client) CreateCanvas(title string, documentContent DocumentContent) (string, error) {
+	return api.CreateCanvasContext(context.Background(), title, documentContent)
+}
+
+// CreateCanvasContext creates a new canvas with a custom context.
+// Slack API docs: https://api.slack.com/methods/canvases.create
+func (api *Client) CreateCanvasContext(ctx context.Context, title string, documentContent DocumentContent) (string, error) {
+	values := url.Values{
+		"token": {api.token},
+	}
+	if title != "" {
+		values.Add("title", title)
+	}
+	if documentContent.Type != "" {
+		documentContentJSON, err := json.Marshal(documentContent)
+		if err != nil {
+			return "", err
+		}
+		values.Add("document_content", string(documentContentJSON))
+	}
+
+	response := struct {
+		SlackResponse
+		CanvasID string `json:"canvas_id"`
+	}{}
+
+	err := api.postMethod(ctx, "canvases.create", values, &response)
+	if err != nil {
+		return "", err
+	}
+
+	return response.CanvasID, response.Err()
+}
+
+// DeleteCanvas deletes an existing canvas.
+// For more details, see DeleteCanvasContext documentation.
+func (api *Client) DeleteCanvas(canvasID string) error {
+	return api.DeleteCanvasContext(context.Background(), canvasID)
+}
+
+// DeleteCanvasContext deletes an existing canvas with a custom context.
+// Slack API docs: https://api.slack.com/methods/canvases.delete
+func (api *Client) DeleteCanvasContext(ctx context.Context, canvasID string) error {
+	values := url.Values{
+		"token":     {api.token},
+		"canvas_id": {canvasID},
+	}
+
+	response := struct {
+		SlackResponse
+	}{}
+
+	err := api.postMethod(ctx, "canvases.delete", values, &response)
+	if err != nil {
+		return err
+	}
+
+	return response.Err()
+}
+
+// EditCanvas edits an existing canvas.
+// For more details, see EditCanvasContext documentation.
+func (api *Client) EditCanvas(params EditCanvasParams) error {
+	return api.EditCanvasContext(context.Background(), params)
+}
+
+// EditCanvasContext edits an existing canvas with a custom context.
+// Slack API docs: https://api.slack.com/methods/canvases.edit
+func (api *Client) EditCanvasContext(ctx context.Context, params EditCanvasParams) error {
+	values := url.Values{
+		"token":     {api.token},
+		"canvas_id": {params.CanvasID},
+	}
+
+	changesJSON, err := json.Marshal(params.Changes)
+	if err != nil {
+		return err
+	}
+	values.Add("changes", string(changesJSON))
+
+	response := struct {
+		SlackResponse
+	}{}
+
+	err = api.postMethod(ctx, "canvases.edit", values, &response)
+	if err != nil {
+		return err
+	}
+
+	return response.Err()
+}
+
+// SetCanvasAccess sets the access level to a canvas for specified entities.
+// For more details, see SetCanvasAccessContext documentation.
+func (api *Client) SetCanvasAccess(params SetCanvasAccessParams) error {
+	return api.SetCanvasAccessContext(context.Background(), params)
+}
+
+// SetCanvasAccessContext sets the access level to a canvas for specified entities with a custom context.
+// Slack API docs: https://api.slack.com/methods/canvases.access.set
+func (api *Client) SetCanvasAccessContext(ctx context.Context, params SetCanvasAccessParams) error {
+	values := url.Values{
+		"token":        {api.token},
+		"canvas_id":    {params.CanvasID},
+		"access_level": {params.AccessLevel},
+	}
+	if len(params.ChannelIDs) > 0 {
+		channelIDsJSON, err := json.Marshal(params.ChannelIDs)
+		if err != nil {
+			return err
+		}
+		values.Add("channel_ids", string(channelIDsJSON))
+	}
+	if len(params.UserIDs) > 0 {
+		userIDsJSON, err := json.Marshal(params.UserIDs)
+		if err != nil {
+			return err
+		}
+		values.Add("user_ids", string(userIDsJSON))
+	}
+
+	response := struct {
+		SlackResponse
+	}{}
+
+	err := api.postMethod(ctx, "canvases.access.set", values, &response)
+	if err != nil {
+		return err
+	}
+
+	return response.Err()
+}
+
+// DeleteCanvasAccess removes access to a canvas for specified entities.
+// For more details, see DeleteCanvasAccessContext documentation.
+func (api *Client) DeleteCanvasAccess(params DeleteCanvasAccessParams) error {
+	return api.DeleteCanvasAccessContext(context.Background(), params)
+}
+
+// DeleteCanvasAccessContext removes access to a canvas for specified entities with a custom context.
+// Slack API docs: https://api.slack.com/methods/canvases.access.delete
+func (api *Client) DeleteCanvasAccessContext(ctx context.Context, params DeleteCanvasAccessParams) error {
+	values := url.Values{
+		"token":     {api.token},
+		"canvas_id": {params.CanvasID},
+	}
+	if len(params.ChannelIDs) > 0 {
+		channelIDsJSON, err := json.Marshal(params.ChannelIDs)
+		if err != nil {
+			return err
+		}
+		values.Add("channel_ids", string(channelIDsJSON))
+	}
+	if len(params.UserIDs) > 0 {
+		userIDsJSON, err := json.Marshal(params.UserIDs)
+		if err != nil {
+			return err
+		}
+		values.Add("user_ids", string(userIDsJSON))
+	}
+
+	response := struct {
+		SlackResponse
+	}{}
+
+	err := api.postMethod(ctx, "canvases.access.delete", values, &response)
+	if err != nil {
+		return err
+	}
+
+	return response.Err()
+}
+
+// LookupCanvasSections finds sections matching the provided criteria.
+// For more details, see LookupCanvasSectionsContext documentation.
+func (api *Client) LookupCanvasSections(params LookupCanvasSectionsParams) ([]CanvasSection, error) {
+	return api.LookupCanvasSectionsContext(context.Background(), params)
+}
+
+// LookupCanvasSectionsContext finds sections matching the provided criteria with a custom context.
+// Slack API docs: https://api.slack.com/methods/canvases.sections.lookup
+func (api *Client) LookupCanvasSectionsContext(ctx context.Context, params LookupCanvasSectionsParams) ([]CanvasSection, error) {
+	values := url.Values{
+		"token":     {api.token},
+		"canvas_id": {params.CanvasID},
+	}
+
+	criteriaJSON, err := json.Marshal(params.Criteria)
+	if err != nil {
+		return nil, err
+	}
+	values.Add("criteria", string(criteriaJSON))
+
+	response := LookupCanvasSectionsResponse{}
+
+	err = api.postMethod(ctx, "canvases.sections.lookup", values, &response)
+	if err != nil {
+		return nil, err
+	}
+
+	return response.Sections, response.Err()
+}