/// <summary>
/// Obtains the command data for a branch.
/// </summary>
/// <param name="range">The range of data to retrieve from a branch.</param>
/// <returns>
/// The command data for the branch (in the order they were created).
/// </returns>
IEnumerable <CmdData> IRemoteStore.GetData(IdRange range)
{
Branch b = FindBranch(range.Id);
if (b == null)
{
throw new ArgumentException(nameof(range.Id));
}
// If the branch hasn't been loaded already, do it now
bool doLoad = b.Commands.Count == 0;
// Ensure we've got a sufficient number of commands loaded
// TODO: When doing a fetch, we will seldom need to load from the beginning
b.Load(range.Max + 1);
// Cycle through the commands in the branch
for (uint i = range.Min; i <= range.Max; i++)
{
yield return(b.Commands[(int)i]);
}
// Release the command data if we had to load it
if (doLoad)
{
b.Unload();
}
}
internal static FileStore Create(CmdData args)
{
// Expand the supplied name to include the current working directory (or
// expand a relative path)
string enteredName = args.GetValue <string>(nameof(ICreateStore.Name));
string name = Path.GetFileNameWithoutExtension(enteredName);
string folderName = Path.GetFullPath(enteredName);
// Disallow if the folder name already exists.
// It may be worth relaxing this rule at some future date. The
// reason for disallowing it is because an existing folder may
// well contain sub-folders, but we also use sub-folders to
// represent the branch hierarchy. So things would be a bit
// mixed up. That said, it would be perfectly plausible to
// place branch sub-folders under a separate ".ac" folder (in
// much the same way as git). That might be worth considering
// if we want to support a "working directory" like that
// provided by git.
if (Directory.Exists(folderName))
{
throw new ApplicationException($"{folderName} already exists");
}
// Confirm the folder is on a local drive
if (!IsLocalDrive(folderName))
{
throw new ApplicationException("Command stores can only be initialized on a local fixed drive");
}
// Create the folder for the store (but if the folder already exists,
// confirm that it does not already hold any AC files).
if (Directory.Exists(folderName))
{
if (GetAcFilePath(folderName) != null)
{
throw new ApplicationException($"{folderName} has already been initialized");
}
}
else
{
Log.Info("Creating " + folderName);
Directory.CreateDirectory(folderName);
}
Guid storeId = args.GetGuid(nameof(ICreateStore.StoreId));
FileStore result = null;
// If we're cloning, copy over the source data
if (args.CmdName == nameof(ICloneStore))
{
// TODO: When cloning from a real remote, using wget might be a
// good choice (but that doesn't really fit with what's below)
ICloneStore cs = (args as ICloneStore);
IRemoteStore rs = GetRemoteStore(cs);
// Retrieve metadata for all remote branches
BranchInfo[] acs = rs.GetBranches()
.OrderBy(x => x.CreatedAt)
.ToArray();
var branchFolders = new Dictionary <Guid, string>();
// Copy over all branches
foreach (BranchInfo ac in acs)
{
// Get the data for the branch (do this before we do any tweaking
// of the folder path from the AC file -- if the command supplier is
// a local file store, we won't be able to read the command data files
// after changing the folder name recorded in the AC)
IdRange range = new IdRange(ac.BranchId, 0, ac.CommandCount - 1);
CmdData[] data = rs.GetData(range).ToArray();
// TODO: what follows is very similar to the CopyIn method.
// Consider using that instead (means an empty FileStore needs
// to be created up front)
// Determine the output location for the AC file (relative to the
// location that should have already been defined for the parent)
if (!branchFolders.TryGetValue(ac.ParentId, out string parentFolder))
{
Debug.Assert(ac.ParentId.Equals(Guid.Empty));
parentFolder = folderName;
}
string dataFolder = Path.Combine(parentFolder, ac.BranchName);
branchFolders[ac.BranchId] = dataFolder;
SaveBranchInfo(dataFolder, ac);
// Copy over the command data
foreach (CmdData cd in data)
{
FileStore.WriteData(dataFolder, cd);
}
}
// If the origin is a folder on the local file system, ensure it's
// saved as an absolute path (relative specs may confuse directory
// navigation, depending on what the current directory is at the time)
string origin = cs.Origin;
if (Directory.Exists(origin))
{
origin = Path.GetFullPath(origin);
}
// Save the store metadata
var root = new StoreInfo(storeId, name, rs.Id, origin);
SaveStoreInfo(folderName, root);
// And suck it back up again
string acSpec = Path.Combine(folderName, acs[0].BranchId + ".ac");
result = FileStore.Load(acSpec);
}
else
{
// Create the AC file that represents the store root branch
var ac = new BranchInfo(storeId: storeId,
parentId: Guid.Empty,
branchId: storeId,
branchName: name,
createdAt: args.CreatedAt);
// Create the store metadata
var storeInfo = new StoreInfo(storeId, name, Guid.Empty);
// Create the store and save it
result = new FileStore(folderName,
storeInfo,
new BranchInfo[] { ac },
ac.BranchId);
// Save the AC file plus the store metadata
FileStore.SaveBranchInfo(folderName, ac);
result.SaveStoreInfo();
}
return(result);
}
