diff options
Diffstat (limited to 'frontend.go')
| -rw-r--r-- | frontend.go | 46 |
1 files changed, 45 insertions, 1 deletions
diff --git a/frontend.go b/frontend.go index d0c8c10..c069ddf 100644 --- a/frontend.go +++ b/frontend.go @@ -1,3 +1,18 @@ +// Copyright (C) 2017-2018 Luke Shumaker <lukeshu@lukeshu.com> +// +// This program is free software: you can redistribute it and/or modify +// it under the terms of the GNU Affero General Public License as published by +// the Free Software Foundation, either version 3 of the License, or +// (at your option) any later version. +// +// This program is distributed in the hope that it will be useful, +// but WITHOUT ANY WARRANTY; without even the implied warranty of +// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +// GNU Affero General Public License for more details. +// +// You should have received a copy of the GNU Affero General Public License +// along with this program. If not, see <https://www.gnu.org/licenses/>. + package libfastimport import ( @@ -15,7 +30,13 @@ func (e UnsupportedCommand) Error() string { } // A Frontend is something that produces a fast-import stream; the -// Frontend object provides methods for reading from it. +// Frontend object provides methods for reading from it. A program +// that writes to a Frontend would itself be a backend. +// +// You may think of a "Frontend" object as a "Reader" object, though +// it was not given that name because the RespondGetMark, +// RespondCatBlob, and RespondLs methods actually write information; +// it isn't a read-only object. type Frontend struct { fastImport *parser catBlobWrite *textproto.CatBlobWriter @@ -24,6 +45,14 @@ type Frontend struct { onErr func(error) error } +// NewFrontend creates a new Frontend object that reads from the given +// io.Reader. +// +// Optionally, you may also provide an io.Writer that responses to +// "cat-blob", "get-mark", and "ls" commands can be written to. +// +// Optionally, you may also provide an onErr function that can bue +// used to handle or transform errors when they are encountered. func NewFrontend(fastImport io.Reader, catBlob io.Writer, onErr func(error) error) *Frontend { ret := &Frontend{} @@ -43,6 +72,7 @@ func NewFrontend(fastImport io.Reader, catBlob io.Writer, onErr func(error) erro return ret } +// ReadCmd reads a command from the Frontend. func (f *Frontend) ReadCmd() (Cmd, error) { cmd, err := f.fastImport.ReadCmd() if err != nil { @@ -51,6 +81,11 @@ func (f *Frontend) ReadCmd() (Cmd, error) { return cmd, err } +// RespondGetMark sends to the Frontend a response to a "get-mark" +// command. +// +// It is an error (panic) to call RespondGetMark if NewFrontend did +// not have a cat-blob writer passed to it. func (f *Frontend) RespondGetMark(sha1 string) error { err := f.catBlobWrite.WriteLine(sha1) if err != nil { @@ -59,6 +94,11 @@ func (f *Frontend) RespondGetMark(sha1 string) error { return f.catBlobFlush.Flush() } +// RespondCatBlob sends to the Frontend a response to a "cat-blob" +// command. +// +// It is an error (panic) to call RespondCatBlob if NewFrontend did +// not have a cat-blob writer passed to it. func (f *Frontend) RespondCatBlob(sha1 string, data string) error { err := f.catBlobWrite.WriteBlob(sha1, data) if err != nil { @@ -67,6 +107,10 @@ func (f *Frontend) RespondCatBlob(sha1 string, data string) error { return f.catBlobFlush.Flush() } +// RespondLs sends to the Frontend a response to a "ls" command. +// +// It is an error (panic) to call RespondLs if NewFrontend did not +// have a cat-blob writer passed to it. func (f *Frontend) RespondLs(mode Mode, dataref string, path Path) error { var err error if mode == 0 { |