GitModel Class Reference

A model that retrieves revision trees from a git repository. More...

#include <GitModel.h>

Inheritance diagram for GitModel:

Classes
class	ChildIndex
	Index usable as a key to a map, that identifies a child/row within a tree. More...
class	Tree
	Used to uniquely locate a folder within the folder hierarchy. More...

Public Member Functions
	GitModel (Wt::WObject *parent=0)
	Constructor. More...
void	setRepositoryPath (const std::string &repositoryPath)
	Set the repository and load its 'master' revision. More...
void	loadRevision (const std::string &revName)
	Load a particular revision. More...
virtual Wt::WModelIndex	parent (const Wt::WModelIndex &index) const
	Returns the parent index. More...
virtual int	columnCount (const Wt::WModelIndex &parent=Wt::WModelIndex()) const
	Returns the column count. More...
virtual int	rowCount (const Wt::WModelIndex &parent=Wt::WModelIndex()) const
	Returns the row count. More...
virtual Wt::WModelIndex	index (int row, int column, const Wt::WModelIndex &parent=Wt::WModelIndex()) const
	Returns a child index. More...
virtual boost::any	data (const Wt::WModelIndex &index, int role=Wt::DisplayRole) const
	Returns data. More...
virtual boost::any	headerData (int section, Wt::Orientation orientation=Wt::Horizontal, int role=Wt::DisplayRole) const
	Returns header data. More...
Public Member Functions inherited from Wt::WAbstractItemModel
	WAbstractItemModel ()
virtual WFlags< ItemFlag >	flags (const WModelIndex &index) const
virtual WFlags< HeaderFlag >	headerFlags (int section, Orientation orientation=Orientation::Horizontal) const
virtual bool	hasChildren (const WModelIndex &index) const
virtual cpp17::any	data (const WModelIndex &index, ItemDataRole role=ItemDataRole::Display) const=0
virtual DataMap	itemData (const WModelIndex &index) const
virtual cpp17::any	headerData (int section, Orientation orientation=Orientation::Horizontal, ItemDataRole role=ItemDataRole::Display) const
virtual WModelIndexList	match (const WModelIndex &start, ItemDataRole role, const cpp17::any &value, int hits=-1, WFlags< MatchFlag > flags=WFlags< MatchFlag >(MatchFlag::StartsWith|MatchFlag::Wrap)) const
cpp17::any	data (int row, int column, ItemDataRole role=ItemDataRole::Display, const WModelIndex &parent=WModelIndex()) const
virtual bool	hasIndex (int row, int column, const WModelIndex &parent=WModelIndex()) const
virtual bool	insertColumns (int column, int count, const WModelIndex &parent=WModelIndex())
virtual bool	insertRows (int row, int count, const WModelIndex &parent=WModelIndex())
virtual bool	removeColumns (int column, int count, const WModelIndex &parent=WModelIndex())
virtual bool	removeRows (int row, int count, const WModelIndex &parent=WModelIndex())
virtual bool	setData (const WModelIndex &index, const cpp17::any &value, ItemDataRole role=ItemDataRole::Edit)
virtual bool	setItemData (const WModelIndex &index, const DataMap &values)
virtual bool	setHeaderData (int section, Orientation orientation, const cpp17::any &value, ItemDataRole role=ItemDataRole::Edit)
bool	setHeaderData (int section, const cpp17::any &value)
virtual void	sort (int column, SortOrder order=SortOrder::Ascending)
virtual void	expandColumn (int column)
virtual void	collapseColumn (int column)
virtual void *	toRawIndex (const WModelIndex &index) const
virtual WModelIndex	fromRawIndex (void *rawIndex) const
virtual std::string	mimeType () const
virtual std::vector< std::string >	acceptDropMimeTypes () const
virtual void	dropEvent (const WDropEvent &e, DropAction action, int row, int column, const WModelIndex &parent)
bool	insertColumn (int column, const WModelIndex &parent=WModelIndex())
bool	insertRow (int row, const WModelIndex &parent=WModelIndex())
bool	removeColumn (int column, const WModelIndex &parent=WModelIndex())
bool	removeRow (int row, const WModelIndex &parent=WModelIndex())
bool	setData (int row, int column, const cpp17::any &value, ItemDataRole role=ItemDataRole::Edit, const WModelIndex &parent=WModelIndex())
virtual Signal< WModelIndex, int, int > &	columnsAboutToBeInserted ()
virtual Signal< WModelIndex, int, int > &	columnsAboutToBeRemoved ()
virtual Signal< WModelIndex, int, int > &	columnsInserted ()
virtual Signal< WModelIndex, int, int > &	columnsRemoved ()
virtual Signal< WModelIndex, int, int > &	rowsAboutToBeInserted ()
virtual Signal< WModelIndex, int, int > &	rowsAboutToBeRemoved ()
virtual Signal< WModelIndex, int, int > &	rowsInserted ()
virtual Signal< WModelIndex, int, int > &	rowsRemoved ()
virtual Signal< WModelIndex, WModelIndex > &	dataChanged ()
virtual Signal< Orientation, int, int > &	headerDataChanged ()
virtual Signal &	layoutAboutToBeChanged ()
virtual Signal &	layoutChanged ()
virtual Signal &	modelReset ()
Public Member Functions inherited from Wt::WObject
void	addChild (std::unique_ptr< WObject > child)
Child *	addChild (std::unique_ptr< Child > child)
std::unique_ptr< WObject >	removeChild (WObject *child)
std::unique_ptr< Child >	removeChild (Child *child)
virtual const std::string	id () const
virtual void	setObjectName (const std::string &name)
virtual std::string	objectName () const
void	resetLearnedSlots ()
void	resetLearnedSlot (void(T::*method)())
WStatelessSlot *	implementStateless (void(T::*method)())
WStatelessSlot *	implementStateless (void(T::*method)(), void(T::*undoMethod)())
void	isNotStateless ()
WStatelessSlot *	implementJavaScript (void(T::*method)(), const std::string &jsCode)
Public Member Functions inherited from Wt::Core::observable
	observable () noexcept
virtual	~observable ()
auto	bindSafe (void(C::*method)(Args...)) noexcept
auto	bindSafe (void(C::*method)(Args...) const) const noexcept
auto	bindSafe (const Function &function) noexcept

Static Public Attributes
static const int	ContentsRole = Wt::UserRole
	The role which may be used on a file to retrieve its contents. More...
static const int	FilePathRole = Wt::UserRole + 1

Private Types
typedef std::map< ChildIndex, int >	ChildPointerMap

Private Member Functions
int	getTreeId (int parentId, int childIndex) const
	Get or allocate an id for a folder. More...
Git::Object	getObject (const Wt::WModelIndex &index) const
	Get the Git::Object that corresponds to an index. More...

Private Attributes
Git	git_
	The git repository. More...
std::vector< Tree >	treeData_
	List of folder objects. More...
ChildPointerMap	childPointer_
	Maps child indexes to tree indexes. More...

Additional Inherited Members
Public Types inherited from Wt::WAbstractItemModel
typedef std::map< ItemDataRole, cpp17::any >	DataMap
Public Types inherited from Wt::WObject
typedef void(WObject::*	Method) ()
Protected Member Functions inherited from Wt::WAbstractItemModel
void	reset ()
WModelIndex	createIndex (int row, int column, void *ptr) const
WModelIndex	createIndex (int row, int column, ::uint64_t id) const
void	beginInsertColumns (const WModelIndex &parent, int first, int last)
void	beginInsertRows (const WModelIndex &parent, int first, int last)
void	beginRemoveColumns (const WModelIndex &parent, int first, int last)
void	beginRemoveRows (const WModelIndex &parent, int first, int last)
void	endInsertColumns ()
void	endInsertRows ()
void	endRemoveColumns ()
void	endRemoveRows ()
Protected Member Functions inherited from Wt::WObject
virtual WStatelessSlot *	getStateless (Method method)

Detailed Description

A model that retrieves revision trees from a git repository.

In its present form, it presents only a single column of data: the file names. Additional data could be easily added. Git "tree" objects correspond to folders, and "blob" objects to files.

The model is read-only, does not support sorting (that could be provided by using a WSortFilterProxyModel).

The model loads only minimal information in memory: to create model indexes for folders. These cannot be uniquely identified by their SHA1 id, since two identical folders at different locations would have the same SHA1 id.

The internal id of model indexes created by the model uniquely identify a containing folder for a particular file.

Definition at line 36 of file GitModel.h.

Member Typedef Documentation

ChildPointerMap

typedef std::map<ChildIndex, int> GitModel::ChildPointerMap

private

Definition at line 168 of file GitModel.h.

Constructor & Destructor Documentation

GitModel()

GitModel::GitModel

(

Wt::WObject *

parent = 0

)

Constructor.

Definition at line 11 of file GitModel.C.

  : WAbstractItemModel(parent)
{ }

Member Function Documentation

columnCount()

int GitModel::columnCount ( const Wt::WModelIndex &  parent = Wt::WModelIndex() ) const

virtual

Returns the column count.

Returns 1.

Implements Wt::WAbstractItemModel.

Definition at line 97 of file GitModel.C.

{
  // currently only one column
  return 1;
}

data()

boost::any GitModel::data ( const Wt::WModelIndex &  index, int  role = Wt::DisplayRole  ) const

virtual

Returns data.

Returns only data corresponding to DisplayRole and ContentsRole.

Definition at line 135 of file GitModel.C.

{
  if (!index.isValid())
    return boost::any();

  /* Only 3 data roles on column 0 data are supported:
   * - DisplayRole: the file name
   * - DecorationRole: an icon (folder or file)
   * - ContentsRole: the file contents
   */
  if (index.column() == 0) {
    Git::Object object = getObject(index);
    if (role == DisplayRole) {
      if (object.type == Git::Tree)
        return object.name + '/';
      else
        return object.name;
    } else if (role == DecorationRole) {
      if (object.type == Git::Blob)
        return static_cast<const char*>("icons/git-blob.png");
      else if (object.type == Git::Tree)
        return static_cast<const char*>("icons/git-tree.png");
    } else if (role == ContentsRole) {
      if (object.type == Git::Blob)
        return git_.catFile(object.id);
    } else if (role == FilePathRole) {
      return boost::any();
    }
  }

  return boost::any();
}

getObject()

Git::Object GitModel::getObject ( const Wt::WModelIndex &  index ) const

private

Get the Git::Object that corresponds to an index.

Definition at line 177 of file GitModel.C.

{
  int parentId = index.internalId();
  const Tree& parentItem = treeData_[parentId];
  return git_.treeGetObject(parentItem.treeObject(), index.row());
}

getTreeId()

int GitModel::getTreeId ( int  parentId, int  childIndex  ) const

private

Get or allocate an id for a folder.

The folder is identified by a given childIndex within a parent folder. This method adds data to the treeData_ (and childPointer_) data structures.

Definition at line 76 of file GitModel.C.

{
  ChildIndex index(parentId, childIndex);

  ChildPointerMap::const_iterator i = childPointer_.find(index);
  if (i == childPointer_.end()) {
    // no tree object was already allocated, so do that now.

    // lookup the git SHA1 object Id (within the parent)
    const Tree& parentItem = treeData_[parentId];
    Git::Object o = git_.treeGetObject(parentItem.treeObject(), childIndex);

    // and add to treeData_ and childPointer_ data structures
    treeData_.push_back(Tree(parentId, childIndex, o.id, git_.treeSize(o.id)));
    int result = treeData_.size() - 1;
    childPointer_[index] = result;
    return result;
  } else
    return i->second;
}

headerData()

boost::any GitModel::headerData ( int  section, Wt::Orientation  orientation = Wt::Horizontal, int  role = Wt::DisplayRole  ) const

virtual

Returns header data.

Definition at line 168 of file GitModel.C.

{
  if (orientation == Horizontal && role == DisplayRole)
    return static_cast<const char*>("File");
  else
    return boost::any();
}

index()

WModelIndex GitModel::index ( int  row, int  column, const Wt::WModelIndex &  parent = Wt::WModelIndex()  ) const

virtual

Returns a child index.

Consults the internal data structure to create a child index. If necessary, the internal data structure is expanded by adding an entry for using the parent index as a parent index.

Implements Wt::WAbstractItemModel.

Definition at line 56 of file GitModel.C.

{
  int parentId;

  // the top-level parent has id=0.
  if (!parent.isValid())
    parentId = 0;
  else {
    // the internal id of the parent identifies the grand parent
    int grandParentId = parent.internalId();

    // lookup the parent id for the parent himself, based on grand parent
    // and child-index (=row) within the grand parent
    parentId = getTreeId(grandParentId, parent.row());
  }

  return createIndex(row, column, parentId);
}

loadRevision()

void GitModel::loadRevision

(

const std::string &

revName

)

Load a particular revision.

The revision name may be any revision accepted by git, by git-rev-parse(1).

Definition at line 21 of file GitModel.C.

{
  Git::ObjectId treeRoot = git_.getCommitTree(revName);

  // You need to call this method before invalidating all existing
  // model indexes. Anyone listening for this event could temporarily
  // convert some model indexes to a raw index pointer, but this model
  // does not reimplement these methods.
  layoutAboutToBeChanged().emit();

  treeData_.clear();
  childPointer_.clear();

  // Store the tree root as treeData_[0]
  treeData_.push_back(Tree(-1, -1, treeRoot, git_.treeSize(treeRoot)));

  layoutChanged().emit();
}

parent()

WModelIndex GitModel::parent ( const Wt::WModelIndex &  index ) const

virtual

Returns the parent index.

Consults the internal data structure to find the parent index.

Implements Wt::WAbstractItemModel.

Definition at line 40 of file GitModel.C.

{
  // treeData_[0] indicates the top-level parent.
  if (!index.isValid() || index.internalId() == 0)
    return WModelIndex();
  else {
    // get the item that corresponds to the parent ...
    const Tree& item = treeData_[index.internalId()];

    // ... and construct that identifies the parent:
    //   row = child index in the grand parent
    //   internalId = id of the grand parent
    return createIndex(item.index(), 0, item.parentId()); 
  }
}

rowCount()

int GitModel::rowCount ( const Wt::WModelIndex &  parent = Wt::WModelIndex() ) const

virtual

Returns the row count.

Returns 0 unless the item represents a folder, in which case it returns the number of items in the tree object that corresponds to the folder.

Implements Wt::WAbstractItemModel.

Definition at line 103 of file GitModel.C.

{
  // we are looking for the git SHA1 id of a tree object (since only folders
  // may contain children).
  Git::ObjectId objectId;
  int treeId;

  if (index.isValid()) {
    // only column 0 items may contain children
    if (index.column() != 0)
      return 0;

    Git::Object o = getObject(index);
    if (o.type == Git::Tree) {
      objectId = o.id;
      treeId = getTreeId(index.internalId(), index.row());
    } else
      // not a folder: no children
      return 0;
  } else {
    treeId = 0;
    // the index corresponds to the root object
    if (treeData_.empty())
      // model not yet loaded !
      return 0;
    else
      objectId = treeData_[0].treeObject();
  }

  return treeData_[treeId].rowCount();
}

setRepositoryPath()

void GitModel::setRepositoryPath

(

const std::string &

repositoryPath

)

Set the repository and load its 'master' revision.

Definition at line 15 of file GitModel.C.

{
  git_.setRepositoryPath(gitRepositoryPath);
  loadRevision("master");
}

Member Data Documentation

childPointer_

ChildPointerMap GitModel::childPointer_

mutableprivate

Maps child indexes to tree indexes.

This map provides a way to lookup data in treeData_. It has an entry corresponding to every entry in treeData_: it maps child indexes for folders to indexes in the treeData_ vector.

It is populated on-the-fly, as the user navigates the model.

Definition at line 192 of file GitModel.h.

ContentsRole

const int GitModel::ContentsRole = Wt::UserRole

static

The role which may be used on a file to retrieve its contents.

Definition at line 41 of file GitModel.h.

FilePathRole

const int GitModel::FilePathRole = Wt::UserRole + 1

static

Definition at line 42 of file GitModel.h.

git_

Git GitModel::git_

private

The git repository.

Definition at line 106 of file GitModel.h.

treeData_

std::vector<Tree> GitModel::treeData_

mutableprivate

List of folder objects.

This list contains folders for which a model index has been allocated.

Model indexes have an internal id that are indexes into this vector, identifying the folder that contains a particular file.

Note: only for folders this is needed, since files will never be used as a 'parent' index.

It is populated on-the-fly, as the user navigates the model.

Definition at line 182 of file GitModel.h.

---

The documentation for this class was generated from the following files:

• /home/roel/project/wt/public-git/wt/examples/gitmodel/GitModel.h
• /home/roel/project/wt/public-git/wt/examples/gitmodel/GitModel.C