2 @documentencoding UTF-8
6 Copyright @copyright{} 2020 @email{stargrave@@stargrave.org, Sergey Matveev}
12 SGBlog is minimalistic and simple Git-backed CGI/inetd
13 @url{https://en.wikipedia.org/wiki/Blog, blogging} and
14 @url{https://en.wikipedia.org/wiki/Phlog, phlogging} engine
15 with email-backed comments support, written on @url{https://golang.org/, Go}.
17 Its main competitive features:
20 @item Single binary, responsible for both blog and phlog
21 @item @url{https://git-scm.com/, Git} DVCS as a storage for posts and comments
22 @item Single small @url{https://hjson.github.io/, Hjson} configuration file
23 @item Uses @url{https://en.wikipedia.org/wiki/Common_Gateway_Interface, CGI}
24 interface (simplicity, remember?) for dealing with HTTP-server
25 @item Uses @url{https://en.wikipedia.org/wiki/Inetd, inetd} interface
26 for working as @url{https://en.wikipedia.org/wiki/Gopher_(protocol), Gopher}
28 @item Topics (tags/categories) support
29 @item Supports on the fly generation of
30 @url{https://en.wikipedia.org/wiki/Atom_(feed), Atom} feeds
31 for posts, comments and per-post comments
32 @item Single binary for email-backed comments posting
33 @item If access is granted, then everyone can easily create an offline
34 copy of your blog/phlog!
37 All of that, except for comments, topics and phlog, could be achieved
38 with some Git viewer like @url{https://git.zx2c4.com/cgit/about/, cgit}.
39 But SGBlog also is able to:
42 @item Convert URLs to clickable links
43 @item Convert SHA1-like hashes to blog links itself
44 @item Include relative @code{<link rel>} links for ease of navigation in
46 @item @url{https://en.wikipedia.org/wiki/Gzip, gzip} compress both HTML
48 @item Respect @url{https://en.wikipedia.org/wiki/HTTP_ETag, ETag}
49 caching for both of them above
52 @url{http://blog.stargrave.org/example/, Here} is an example blog.
54 SGBlog is free software, licenced under
55 @url{https://www.gnu.org/licenses/agpl-3.0.html, GNU AGPLv3}:
56 see the file COPYING for copying conditions.
68 Comments are posted through the email interface, just by sending the
69 message to special address. For example:
72 $ mutt "mailto:comment@@blog.example.com?subject=576540a5b98517b46d0efc791bb90b9121bf147e" <<EOF
73 This is the comments contents.
74 Could be multilined of course.
78 Comments are stored in Git as a @url{https://git-scm.com/docs/git-notes, note}.
79 Those objects could be updated without touching the base commit itself.
81 Each comment is just a plaintext with @code{From} and @code{Date}
82 headers. @code{From} is a name of email sender (with email address
85 Technically comments are stored in concatenated
86 @url{https://en.wikipedia.org/wiki/Netstring, netstring}. Only
87 @code{text/plain} or @code{multipart/signed+text/plain} email messages
88 are accepted and only with UTF-8, US-ASCII, ISO-8859-1 character sets.
89 Sane people won't send HTML email anyway, but this is just a precaution.
94 Each post can have any number of attached topics (also known as tags or
95 categories). They are whitespace separated single words kept in separate
96 @url{https://git-scm.com/docs/git-notes, note} namespace. You can
97 add/change comments with commands like:
100 $ git notes --ref=topics add -m "linux hate" @@
104 @unnumbered Installation
106 SGBlog's is written on Go and uses its modules. Hopefully you can
107 install it just by running:
110 $ go get go.stargrave.org/sgblog/cmd/sgblog
111 $ go get go.stargrave.org/sgblog/cmd/sgblog-comment-add # if you need commenting
114 Unfortunately by default it uses HTTPS and Go's third party servers
115 (@code{sum.golang.org}, @code{proxy.golang.org}) that trust neither
116 @code{CACert.org}'s CA (used previously) nor @code{ca.cypherpunks.ru}
117 CA. So either disable their usage and trust that certificate:
118 @code{GOPRIVATE=go.stargrave.org/sgblog}, or clone its source code
119 manually and build in place:
120 @url{git://git.stargrave.org/sgblog.git},
121 @url{https://git.stargrave.org/git/sgblog.git}.
123 For enabling blog availability you have to use HTTP server with CGI
124 interface. Example part of @url{http://www.lighttpd.net/, lighttpd}'s
128 $HTTP["host"] == "blog.example.com" @{
129 server.document-root = www_dir + "/blog.example.com"
130 $HTTP["url"] =~ "^/example" @{
131 alias.url += ("/example" => "/path/to/sgblog")
132 cgi.assign = ("sgblog" => "/path/to/sgblog")
133 setenv.add-environment = (
134 "SGBLOG_CFG" => "/path/to/example.hjson",
140 And be sure that you have read access to the Git repository, for example
141 by placing @code{lighttpd} user into @code{git} group.
143 Example @command{inetd} configuration (for phlog):
146 gopher stream tcp nowait lighttpd /path/to/sgblog sgblog -gopher /path/to/gopher.hjson
147 gopher stream tcp6 nowait lighttpd /path/to/sgblog sgblog -gopher /path/to/gopher.hjson
150 For comments workability you have to configure your SMTP server to feed
151 incoming messages to @command{sgblog-comment-add} utility. For example,
152 Postfix'es @file{/etc/aliases} can contain:
155 comment: "| /path/to/sgblog-comment-add -git-dir /path/to/blog.git -committer-email comment@@blog.example.com"
158 to run that utility for all @code{comment@@} address messages.
159 You must have enough permission to be able to write to Git repository,
160 but Postfix by default runs all that commands from a @code{nobody} user.
161 So possibly you will need to @code{setuid} that executable give
162 permission for @code{nobody} running:
165 -rwsr-x--- git:nobody sgblog-comment-add
168 And also do not forget about @code{lighttpd} user's (possibly in
169 @code{git} group) read permission permissions. Make sure
170 @command{sgblog-comment-add} runs with correctly set @code{-umask} (027
171 by default) for newly created Git objects/files.
174 @unnumbered Configuration
176 SGBlog is configured via Hjson configuration file. More or less
177 self-describing blog configuration looks like that and contains many
182 GitPath: /home/sgblog/blog.git
183 Branch: refs/heads/example
184 Title: "Example blog"
186 BaseURL: http://blog.example.com
189 AtomId: "urn:uuid:54e6e53f-c615-48f1-812c-6f6b094ebbdd"
192 # URL to CSS file, optional
194 # Email address of the webmaster, optional
195 Webmaster: "webmaster@@example.com"
196 # URL to about page, optional
198 # Optional list of optional Git URLs for corresponding <link rel="vcs-git">
200 git://git.example.com/blog.git
201 https://git.example.com/git/blog.git
204 # If that ref is set, then comments will be loaded from it
205 CommentsNotesRef: refs/notes/comments
206 # Display link for comment writing, if email is set
207 CommentsEmail: something@@example.com
209 # If that ref is set, then topics will be loaded from it
210 TopicsNotesRef: refs/notes/topics
211 # Optional file for topics state caching
212 TopicsCachePath: /path/to/sgblog-topics-cache.gob
216 Gopher configuration can use the same file, but it requires much less
221 GitPath: /home/sgblog/blog.git
222 Branch: refs/heads/example
223 Title: "Example blog"
225 GopherDomain: phlog.example.com
227 AboutURL: http://blog.example.com/
230 CommentsNotesRef: refs/notes/comments
231 CommentsEmail: something@@example.com
233 # Both are optional too
234 TopicsNotesRef: refs/notes/topics
235 TopicsCachePath: /path/to/sgblog-topics-cache.gob