## The basics
- [x] I [validated my changes](https://developers.google.com/blockly/guides/contribute/core#making_and_verifying_a_change)
## The details
### Resolves
Fixes https://github.com/google/blockly-keyboard-experimentation/issues/515
### Proposed Changes
This adds `canBeFocused()` checks to all the places that could currently cause problems if a node were to return `false`.
### Reason for Changes
This can't introduce a problem in current Core and, in fact, most of these classes can never return `false` even through subclasses. However, this adds better robustness and fixes the underlying issue by ensuring that `getFocusableElement()` isn't called for a node that has indicated it cannot be focused.
### Test Coverage
I've manually tested this through the keyboard navigation plugin. However, there are clearly additional tests that would be nice to add both for the traverser and for `WorkspaceSvg`, both likely as part of resolving #8915.
### Documentation
No new documentation changes should be needed here.
### Additional Information
This is fixing theoretical issues in Core, but a real issue tracked by the keyboard navigation plugin repository.
* feat!: Make bubbles, comments, and icons focusable
* feat!: Make ISelectable and ICopyable focusable.
* feat: Consolidate selection calls.
Now everything is based on focus with selection only being used as a
proxy.
* feat: Invert responsibility for setSelected().
Now setSelected() is only for quasi-external use.
* feat: Push up shadow check to getters.
Needed new common-level helper.
* chore: Lint fixes.
* feat!: Allow IFocusableNode to disable focus.
* chore: post-merge lint fixes
* fix: Fix tests + text bubble focusing.
This fixed then regressed a circular dependency causing the node and
advanced compilation steps to fail. This investigation is ongoing.
* fix: Clean up & fix imports.
This ensures the node and advanced compilation test steps now pass.
* fix: Lint fixes + revert commented out logic.
* chore: Remove unnecessary cast.
Addresses reviewer comment.
* fix: Some issues and a bunch of clean-ups.
This addresses a bunch of review comments, and fixes selecting workspace
comments.
* chore: Lint fix.
* fix: Remove unnecessary shadow consideration.
* chore: Revert import.
* chore: Some doc updates & added a warn statement.
* feat: Add interfaces for keyboard navigation.
* feat: Add the Navigator.
* feat: Make core types conform to INavigable.
* feat: Require FlyoutItems elements to be INavigable.
* feat: Add navigation policies for built-in types.
* refactor: Convert Marker and LineCursor to operate on INavigables instead of ASTNodes.
* chore: Delete dead code in ASTNode.
* fix: Fix the tests.
* chore: Assuage the linter.
* fix: Fix advanced build/tests.
* chore: Restore ASTNode tests.
* refactor: Move isNavigable() validation into Navigator.
* refactor: Exercise navigation instead of ASTNode.
* chore: Rename astnode_test.js to navigation_test.js.
* chore: Enable the navigation tests.
* fix: Fix bug when retrieving the first child of an empty workspace.
## The basics
- [x] I [validated my changes](https://developers.google.com/blockly/guides/contribute/core#making_and_verifying_a_change)
## The details
### Resolves
Fixes#8976
### Proposed Changes
Only auto-close the flyout if focus is being lost to a known tree.
### Reason for Changes
I noticed from testing that the system does attempt to restore focus back to the flyout after creating a variable but the auto-closing logic was kicking in due to focus being lost with the variable creation prompt open. Even though an attempt was made to restore focus, this doesn't automatically reopen the flyout (since it is primarily governed by the toolbox selection state).
One alternative might be to try and save the previously selected toolbox category and restore it, but that's tricky. This seems simpler, and also seems to largely maintain parity with pre-focus manager Blockly. Clicking outside of the toolbox with the flyout open only closes it if the click is within the toolbox itself or within the workspace.
### Test Coverage
No new tests were added. However, it may be worth considering this specific case for future tests added with #8915.
### Documentation
No new documentation seems necessary here.
### Additional Information
None.
* feat(WorkspaceSvg): Ignore gestures during keyboard moves
Modify WorkspaceSvg.prototype.getGesture to return null when
there is a keyboard-initiated move in progress.
* chore(WorkspaceSvg): Add TODOs to remove .keyboardMoveInProgress
* docs: Make JSDoc @deprecated usage more consistent
* refactor(VariableMap)!: Refresh toolbox when map modified
Delete the following methods from WorkspaceSvg:
- renameVariableById
- deleteVariableById
- createVariable
Modify the following methods on VariableMap to call
this.workspace.refreshToolboxSelection() if this.workspace
is a WorkspaceSvg, replicating the behaviour of the
aforementioned deleted methods and additionally ensuring
that that method is called following any change to the
variable map:
- renameVariable
- changeVariableType
- renameVariableAndUses
- createVariable
- addVariable
- deleteVariable
BREAKING CHANGE:
This change ensures that the toolbox will be refreshed regardless
of what route the VaribleMap was updated, rather than only being
refreshed when it is updated via calls to methods on WorkspaceSvg.
Overall this is much more likely to fix a bug (where the toolbox
wasn't being refreshed when it should have been) than cause one
(by refreshing the toolbox when it shouldn't be), but this is
still a behaviour change which could _conceivably_ result an
unexpected regression.
* refactor(VariableMap): Remove calls to deprecated getVariableUsesById
Also refactor to use named imports core/variables.ts methods.
* refactor(Workspace): Use named imports for core/variables.ts methods
* refactor(FieldVariable): Remove call to deprecated getVariablesOfType
* refactor(variables): Remove calls to deprecated methods
* refactor(variables_dynamic): Remove call to deprecated getAllVariables
* refactor(xml): Remove calls to deprecated createVariable
* refactor(Events.VarCreate): Remove calls to deprecated methods
* refactor(Events.VarDelete): Remove calls to deprecated methods
* refactor(Events.VarRename): Remove calls to deprecated methods
## The basics
- [x] I [validated my changes](https://developers.google.com/blockly/guides/contribute/core#making_and_verifying_a_change)
## The details
### Resolves
Fixes#8930
Fixes part of #8771
### Proposed Changes
This PR introduces support for connections to be focusable (and thus navigable with keyboard navigation when paired with downstream changes to `LineCursor` and the keyboard navigation plugin). This is a largely isolated change in how it fundamentally works:
- `RenderedConnection` has been updated to be an `IFocusableNode` using a new unique ID maintained by `Connection` and automatically enabling/disabling the connection highlight based on whether it's focused (per keyboard navigation).
- The way that rendering works here has changed: rather than recreating the connection's highlight SVG each time, it's only created once and updated thereafter to ensure that it correctly fits block resizes or movements. Visibility of the highlight is controlled entirely through display visibility and can now be done synchronously (which was a requirement for focusability as only displayed elements can be focused).
- This employs the same type of ID schema strategy as fields in #8923.
### Reason for Changes
This is part of an ongoing effort to ensure key components of Blockly are focusable so that they can be keyboard-navigable (with other needed changes yet both in Core Blockly and the keyboard navigation plugin).
### Test Coverage
No new tests have been added. It's certainly possible to add unit tests for the focusable configurations being introduced in this PR, but it may not be highly beneficial. It's largely assumed that the individual implementations should work due to a highly tested FocusManager, and it may be the case that the interactions of the components working together is far more important to verify (that is, the end user flows). The latter is planned to be tackled as part of #8915.
### Documentation
No documentation changes should be needed here.
### Additional Information
This includes changes that have been pulled from #8875.
## The basics
- [x] I [validated my changes](https://developers.google.com/blockly/guides/contribute/core#making_and_verifying_a_change)
## The details
### Resolves
Fixes#8922Fixes#8929
Fixes part of #8771
### Proposed Changes
This PR introduces support for fields to be focusable (and thus navigable with keyboard navigation when paired with downstream changes to `LineCursor` and the keyboard navigation plugin). This is a largely isolated change in how it fundamentally works:
- `Field` was updated to become an `IFocusableNode`. Note that it uses a specific string-based ID schema in order to ensure that it can be properly linked back to its unique block (which helps make the search for the field in `WorkspaceSvg` a bit more efficient). This could be done with a globally unique ID, instead, but all fields would need to be searched vs. just those for the field's parent block.
- The drop-down and widget divs have been updated to manage ephemeral focus with `FocusManager` when they're open for non-system dialogs (ephemeral focus isn't needed for system dialogs/prompts since those already take/restore focus in a native way that `FocusManager` will respond to--this may require future work, however, if the restoration causes unexpected behavior for users). This approach was done due to a suggestion from @maribethb as the alternative would be a more complicated breaking change (forcing `Field` subclasses to properly manage ephemeral focus). It may still be the case that certain cases will need to do so, but widget and drop-down divs seem to address the majority of possibilities.
**Important**: `Input`s are not explicitly being supported here. As far as I can tell, we can't run into a case where `LineCursor` tries to set an input node, though perhaps I simply haven't come across this case. Supporting `Fields` and `Connections` (per #8928) seems to cover the main needed cases, though making `Input`s focusable may be a future requirement.
### Reason for Changes
This is part of an ongoing effort to ensure key components of Blockly are focusable so that they can be keyboard-navigable (with other needed changes yet both in Core Blockly and the keyboard navigation plugin).
Note that #8929 isn't broadly addressed since making widget & drop down divs manage ephemeral focus directly addresses a large class of cases. Additional cases may arise where a plugin or Blockly integration may require additional effort to make keyboard navigation work for their field--this may be best addressed with documentation and guidance.
### Test Coverage
No new tests have been added. It's certainly possible to add unit tests for the focusable configurations being introduced in this PR, but it may not be highly beneficial. It's largely assumed that the individual implementations should work due to a highly tested FocusManager, and it may be the case that the interactions of the components working together is far more important to verify (that is, the end user flows). The latter is planned to be tackled as part of #8915.
### Documentation
No new documentation is planned, however it may be prudent to update the field documentation in the future to explain how to utilize ephemeral focus when specifically building compatibility for keyboard navigation.
### Additional Information
This includes changes that have been pulled from #8875.
_Note: This is a roll forward of #8920 that was reverted in #8933. See Additional Information below._
## The basics
- [x] I [validated my changes](https://developers.google.com/blockly/guides/contribute/core#making_and_verifying_a_change)
## The details
### Resolves
Fixes#8918Fixes#8919
Fixes part of #8943
Fixes part of #8771
### Proposed Changes
This updates several classes in order to make toolboxes and flyouts focusable:
- `IFlyout` is now an `IFocusableTree` with corresponding implementations in `FlyoutBase`.
- `IToolbox` is now an `IFocusableTree` with corresponding implementations in `Toolbox`.
- `IToolboxItem` is now an `IFocusableNode` with corresponding implementations in `ToolboxItem`.
- As the primary toolbox items, `ToolboxCategory` and `ToolboxSeparator` were updated to have -1 tab indexes and defined IDs to help `ToolboxItem` fulfill its contracted for `IFocusableNode.getFocusableElement`.
- `FlyoutButton` is now an `IFocusableNode` (with corresponding ID generation, tab index setting, and ID matching for retrieval in `WorkspaceSvg`).
Each of these two new focusable trees have specific noteworthy behaviors behaviors:
- `Toolbox` will automatically indicate that its first item should be focused (if one is present), even overriding the ability to focus the toolbox's root (however there are some cases where that can still happen).
- `Toolbox` will automatically synchronize its selection state with its item nodes being focused.
- `FlyoutBase`, now being a focusable tree, has had a tab index of 0 added. Normally a tab index of -1 is all that's needed, but the keyboard navigation plugin specifically uses 0 for flyout so that the flyout is tabbable. This is a **new** tab stop being introduced.
- `FlyoutBase` holds a workspace (for rendering blocks) and, since `WorkspaceSvg` is already set up to be a focusable tree, it's represented as a subtree to `FlyoutBase`. This does introduce some wonky behaviors: the flyout's root will have passive focus while its contents have active focus. This could be manually disabled with some CSS if it ends up being a confusing user experience.
- Both `FlyoutBase` and `WorkspaceSvg` have built-in behaviors for detecting when a user tries navigating away from an open flyout to ensure that the flyout is closed when it's supposed to be. That is, the flyout is auto-hideable and a non-flyout, non-toolbox node has then been focused. This matches parity with the `T`/`Esc` flows supported in the keyboard navigation plugin playground.
One other thing to note: `Toolbox` had a few tests to update that were trying to reinit a toolbox without first disposing of it (which was caught by one of `FocusManager`'s state guardrails).
This only addresses part of #8943: it adds support for `FlyoutButton` which covers both buttons and labels. However, a longer-term solution may be to change `FlyoutItem` itself to force using an `IFocusableNode` as its element.
### Reason for Changes
This is part of an ongoing effort to ensure key components of Blockly are focusable so that they can be keyboard-navigable (with other needed changes yet both in Core Blockly and the keyboard navigation plugin).
### Test Coverage
No new tests have been added. It's certainly possible to add unit tests for the focusable configurations being introduced in this PR, but it may not be highly beneficial. It's largely assumed that the individual implementations should work due to a highly tested FocusManager, and it may be the case that the interactions of the components working together is far more important to verify (that is, the end user flows). The latter is planned to be tackled as part of #8915.
### Documentation
No documentation changes should be needed here.
### Additional Information
This includes changes that have been pulled from #8875.
This was originally merged in #8916 but was reverted in #8933 due to https://github.com/google/blockly-keyboard-experimentation/issues/481. Note that this does contain a number of differences from the original PR (namely, changes in `WorkspaceSvg` and `FlyoutButton` in order to make `FlyoutButton`s focusable). Otherwise, this has the same caveats as those noted in #8938 with regards to the experimental keyboard navigation plugin.
_Note: This is a roll forward of #8916 that was reverted in #8933. See Additional Information below._
## The basics
- [x] I [validated my changes](https://developers.google.com/blockly/guides/contribute/core#making_and_verifying_a_change)
## The details
### Resolves
Fixes#8913Fixes#8914
Fixes part of #8771
### Proposed Changes
This updates `WorkspaceSvg` and `BlockSvg` to be focusable, that is, it makes the workspace a `IFocusableTree` and blocks `IFocusableNode`s.
Some important details:
- While this introduces focusable tree support for `Workspace` it doesn't include two other components that are obviously needed by the keyboard navigation plugin's playground: fields and connections. These will be introduced in subsequent PRs.
- Blocks are set up to automatically synchronize their selection state with their focus state. This will eventually help to replace `LineCursor`'s responsibility for managing selection state itself.
- The tabindex property for the workspace and its ARIA label have been moved down to the `.blocklyWorkspace` element itself rather than its wrapper. This helps address some tab stop issues that are already addressed in the plugin (via monkey patches), but also to ensure that the workspace's main SVG group interacts correctly with `FocusManager`.
- `WorkspaceSvg` is being initially set up to default to its first top block when being focused for the first time. This is to match parity with the keyboard navigation plugin, however the latter also has functionality for defaulting to a position when no blocks are present. It's not clear how to actually support this under the new focus-based system (without adding an ephemeral element on which to focus), or if it's even necessary (since the workspace root can hold focus).
- `css.ts` was updated to remove `blocklyActiveFocus` and `blocklyPassiveFocus` since these have unintended highlighting consequences that aren't actually desirable yet. Instead, the exact styling for active/passive focus will be iterated in the keyboard navigation plugin project and moved to Core once finalized.
### Reason for Changes
This is part of an ongoing effort to ensure key components of Blockly are focusable so that they can be keyboard-navigable (with other needed changes yet both in Core Blockly and the keyboard navigation plugin).
### Test Coverage
No new tests have been added. It's certainly possible to add unit tests for the focusable configurations being introduced in this PR, but it may not be highly beneficial. It's largely assumed that the individual implementations should work due to a highly tested FocusManager, and it may be the case that the interactions of the components working together is far more important to verify (that is, the end user flows). The latter is planned to be tackled as part of #8915.
### Documentation
No documentation changes should be needed here.
### Additional Information
This includes changes that have been pulled from #8875.
This was originally merged in #8916 but was reverted in #8933 due to https://github.com/google/blockly-keyboard-experimentation/issues/481. This actually contains no differences from the original PR except for `css.ts` which are documented above. It does employ a new merge strategy: all of the necessary PRs to move both Core and the plugin over to using `FocusManager` will be staged and merged in quick succession as ensuring the plugin works for each constituent change (vs. the final one) is quite complex. Thus, this PR *does* break the plugin, and won't be merged until its subsequent PRs are approved and also ready for merging.
Edit: See https://github.com/google/blockly/pull/8938#issuecomment-2843589525 for why this actually is being merged a bit sooner than originally planned. Keeping the original reasoning above for context.
* Revert "feat: Make toolbox and flyout focusable (#8920)"
This reverts commit 5bc83808bf.
* Revert "feat: Make WorkspaceSvg and BlockSvg focusable (#8916)"
This reverts commit d7680cf32e.
## The basics
- [x] I [validated my changes](https://developers.google.com/blockly/guides/contribute/core#making_and_verifying_a_change)
## The details
### Resolves
Fixes#8918Fixes#8919
Fixes part of #8771
### Proposed Changes
This updates several classes in order to make toolboxes and flyouts focusable:
- `IFlyout` is now an `IFocusableTree` with corresponding implementations in `FlyoutBase`.
- `IToolbox` is now an `IFocusableTree` with corresponding implementations in `Toolbox`.
- `IToolboxItem` is now an `IFocusableNode` with corresponding implementations in `ToolboxItem`.
- As the primary toolbox items, `ToolboxCategory` and `ToolboxSeparator` were updated to have -1 tab indexes and defined IDs to help `ToolboxItem` fulfill its contracted for `IFocusableNode.getFocusableElement`.
Each of these two new focusable trees have specific noteworthy behaviors behaviors:
- `Toolbox` will automatically indicate that its first item should be focused (if one is present), even overriding the ability to focus the toolbox's root (however there are some cases where that can still happen).
- `Toolbox` will automatically synchronize its selection state with its item nodes being focused.
- `FlyoutBase`, now being a focusable tree, has had a tab index of 0 added. Normally a tab index of -1 is all that's needed, but the keyboard navigation plugin specifically uses 0 for flyout so that the flyout is tabbable. This is a **new** tab stop being introduced.
- `FlyoutBase` holds a workspace (for rendering blocks) and, since `WorkspaceSvg` is already set up to be a focusable tree, it's represented as a subtree to `FlyoutBase`. This does introduce some wonky behaviors: the flyout's root will have passive focus while its contents have active focus. This could be manually disabled with some CSS if it ends up being a confusing user experience.
- Both `FlyoutBase` and `WorkspaceSvg` have built-in behaviors for detecting when a user tries navigating away from an open flyout to ensure that the flyout is closed when it's supposed to be. That is, the flyout is auto-hideable and a non-flyout, non-toolbox node has then been focused. This matches parity with the `T`/`Esc` flows supported in the keyboard navigation plugin playground.
One other thing to note: `Toolbox` had a few tests to update that were trying to reinit a toolbox without first disposing of it (which was caught by one of `FocusManager`'s state guardrails).
### Reason for Changes
This is part of an ongoing effort to ensure key components of Blockly are focusable so that they can be keyboard-navigable (with other needed changes yet both in Core Blockly and the keyboard navigation plugin).
### Test Coverage
No new tests have been added. It's certainly possible to add unit tests for the focusable configurations being introduced in this PR, but it may not be highly beneficial. It's largely assumed that the individual implementations should work due to a highly tested FocusManager, and it may be the case that the interactions of the components working together is far more important to verify (that is, the end user flows). The latter is planned to be tackled as part of #8915.
### Documentation
No documentation changes should be needed here.
### Additional Information
This includes changes that have been pulled from #8875.
## The basics
- [x] I [validated my changes](https://developers.google.com/blockly/guides/contribute/core#making_and_verifying_a_change)
## The details
### Resolves
Fixes#8913Fixes#8914
Fixes part of #8771
### Proposed Changes
This updates `WorkspaceSvg` and `BlockSvg` to be focusable, that is, it makes the workspace a `IFocusableTree` and blocks `IFocusableNode`s.
Some important details:
- While this introduces focusable tree support for `Workspace` it doesn't include two other components that are obviously needed by the keyboard navigation plugin's playground: fields and connections. These will be introduced in subsequent PRs.
- Blocks are set up to automatically synchronize their selection state with their focus state. This will eventually help to replace `LineCursor`'s responsibility for managing selection state itself.
- The tabindex property for the workspace and its ARIA label have been moved down to the `.blocklyWorkspace` element itself rather than its wrapper. This helps address some tab stop issues that are already addressed in the plugin (via monkey patches), but also to ensure that the workspace's main SVG group interacts correctly with `FocusManager`.
- `WorkspaceSvg` is being initially set up to default to its first top block when being focused for the first time. This is to match parity with the keyboard navigation plugin, however the latter also has functionality for defaulting to a position when no blocks are present. It's not clear how to actually support this under the new focus-based system (without adding an ephemeral element on which to focus), or if it's even necessary (since the workspace root can hold focus).
### Reason for Changes
This is part of an ongoing effort to ensure key components of Blockly are focusable so that they can be keyboard-navigable (with other needed changes yet both in Core Blockly and the keyboard navigation plugin).
### Test Coverage
No new tests have been added. It's certainly possible to add unit tests for the focusable configurations being introduced in this PR, but it may not be highly beneficial. It's largely assumed that the individual implementations should work due to a highly tested FocusManager, and it may be the case that the interactions of the components working together is far more important to verify (that is, the end user flows). The latter is planned to be tackled as part of #8915.
### Documentation
No documentation changes should be needed here.
### Additional Information
This includes changes that have been pulled from #8875.
* refactor: Backport LineCursor to core.
* fix: Fix instantiation of LineCursor.
* fix: Fix tests.
* chore: Assauge the linter.
* chore: Fix some typos.
* feat: Make padding configurable for scrollBoundsIntoView.
* chore: Merge in the latest changes from keyboard-experimentation.
* refactor: Clarify name and docs for findSiblingOrParentSibling().
* fix: Improve scrollBoundsIntoView() behavior.
* fix: Export CursorOptions.
* refactor: Further clarify second parameter of setCurNode().
* fix: Revert change that could prevent scrolling bounds into view.
* feat: Add methods for toggling and inspecting the readonly state of a workspace.
* refactor: Use the new readonly setters/getters in place of checking the injection options.
* fix: Fix bug that allowed dragging blocks from a flyout onto a readonly workspace.
* feat: Toggle a `blocklyReadOnly` class when readonly status is changed.
* chore: Placate the linter.
* chore: Placate the compiler.
* chore: rename .eslintrc.js to eslint.config.js
* chore: Rename eslint.config.js to eslint.config.mjs.
* refactor: Migrate ESLint config to new flat format.
* chore: Remove old per-directory and global ignore ESLint config files.
* fix: Allowlist JSDoc tag aliases.
* fix: Don't require @license in tests/*.
* fix: Add NodeJS globals to several files that run under Node.
* chore: Remove now-unneeded ESLint directives in core.
* chore: Remove invalid/unneeded ESLint directives.
* fix: Fix invalid use of `await` outside of an `async` function.
* fix: Improve screenshot error message.
* fix: Update ESLint config file to not warn on existing violations.
* chore: Remove suppressions of rules that weren't triggering.
* chore: Fix package-lock.json.
At a high-level, this change ensures that cleaning up a workspace
doesn't move blocks in a way that overlaps with immovable blocks. It
also adds missing testing coverage for both Rect (used for bounding box
calculations during workspace cleanup) and WorkspaceSvg (for verifying
the updated clean up functionality).
This also renames the clean up function to be 'tidyUp' since that better
suits what's happening (as opposed to other clean-up routines which are
actually deinitializing objects).
* refactor(events): Use "export ... from" where applicable
* refactor(events): Introduce EventType enum
Introduce an enum for the event .type values. We can't actually
use it as the type of the .type property on Abstract events,
because we want to allow developers to add their own custom
event types inheriting from this type, but at least this way we
can be reasonably sure that all of our own event subclasses have
distinct .type values—plus consistent use of enum syntax
(EventType.TYPE_NAME) is probably good for readability overall.
Put it in a separate module from the rest of events/utils.ts
because it would be helpful if event utils could use
event instanceof SomeEventType
for type narrowing but but at the moment most events are in
modules that depend on events/utils.ts for their .type
constant, and although circular ESM dependencies should work
in principle there are various restrictions and this
particular circularity causes issues at the moment.
A few of the event classes also depend on utils.ts for fire()
or other functions, which will be harder to deal with, but at
least this commit is win in terms of reducing the complexity
of our dependencies, making most of the Abstract event subclass
module dependent on type.ts, which has no imports, rather than
on utils.ts which has multiple imports.
* chore(deps): Add pretter-plugin-organize-imports
* chore: Remove insignificant blank lines in import sections
Since prettier-plugin-organize-imports sorts imports within
sections separated by blank lines, but preserves the section
divisions, remove any blank lines that are not dividing imports
into meaningful sections.
Do not remove blank lines separating side-effect-only imports
from main imports.
* chore: Remove unneded eslint-disable directives
* chore: Organise imports