Merge branch 'ab/receive-pack-use-after-free-fix'
[git/git.git] / contrib / hooks / multimail / README.migrate-from-post-receive-email
1 git-multimail is close to, but not exactly, a plug-in replacement for
2 the old Git project script contrib/hooks/post-receive-email. This
3 document describes the differences and explains how to configure
4 git-multimail to get behavior closest to that of post-receive-email.
5
6 If you are in a hurry
7 =====================
8
9 A script called migrate-mailhook-config is included with
10 git-multimail. If you run this script within a Git repository that is
11 configured to use post-receive-email, it will convert the
12 configuration settings into the approximate equivalent settings for
13 git-multimail. For more information, run
14
15 migrate-mailhook-config --help
16
17
18 Configuration differences
19 =========================
20
21 * The names of the config options for git-multimail are in namespace
22 "multimailhook.*" instead of "hooks.*". (Editorial comment:
23 post-receive-email should never have used such a generic top-level
24 namespace.)
25
26 * In emails about new annotated tags, post-receive-email includes a
27 shortlog of all changes since the previous annotated tag. To get
28 this behavior with git-multimail, you need to set
29 multimailhook.announceshortlog to true:
30
31 git config multimailhook.announceshortlog true
32
33 * multimailhook.commitlist -- This is a new configuration variable.
34 Recipients listed here will receive a separate email for each new
35 commit. However, if this variable is *not* set, it defaults to the
36 value of multimailhook.mailinglist. Therefore, if you *don't* want
37 the members of multimailhook.mailinglist to receive one email per
38 commit, then set this value to the empty string:
39
40 git config multimailhook.commitlist ''
41
42 * multimailhook.emailprefix -- If this value is not set, then the
43 subjects of generated emails are prefixed with the short name of the
44 repository enclosed in square brackets; e.g., "[myrepo]".
45 post-receive-email defaults to prefix "[SCM]" if this option is not
46 set. So if you were using the old default and want to retain it
47 (for example, to avoid having to change your email filters), set
48 this variable explicitly to the old value:
49
50 git config multimailhook.emailprefix "[SCM]"
51
52 * The "multimailhook.showrev" configuration option is not supported.
53 Its main use is obsoleted by the one-email-per-commit feature of
54 git-multimail.
55
56
57 Other differences
58 =================
59
60 This section describes other differences in the behavior of
61 git-multimail vs. post-receive-email. For full details, please refer
62 to the main README file:
63
64 * One email per commit. For each reference change, the script first
65 outputs one email summarizing the reference change (including
66 one-line summaries of the new commits), then it outputs a separate
67 email for each new commit that was introduced, including patches.
68 These one-email-per-commit emails go to the addresses listed in
69 multimailhook.commitlist. post-receive-email sends only one email
70 for each *reference* that is changed, no matter how many commits
71 were added to the reference.
72
73 * Better algorithm for detecting new commits. post-receive-email
74 processes one reference change at a time, which causes it to fail to
75 describe new commits that were included in multiple branches. For
76 example, if a single push adds the "*" commits in the diagram below,
77 then post-receive-email would never include the details of the two
78 commits that are common to "master" and "branch" in its
79 notifications.
80
81 o---o---o---*---*---* <-- master
82 \
83 *---* <-- branch
84
85 git-multimail analyzes all reference modifications to determine
86 which commits were not present before the change, therefore avoiding
87 that error.
88
89 * In reference change emails, git-multimail tells which commits have
90 been added to the reference vs. are entirely new to the repository,
91 and which commits that have been omitted from the reference
92 vs. entirely discarded from the repository.
93
94 * The environment in which Git is running can be configured via an
95 "Environment" abstraction.
96
97 * Built-in support for Gitolite-managed repositories.
98
99 * Instead of using full SHA1 object names in emails, git-multimail
100 mostly uses abbreviated SHA1s, plus one-line log message summaries
101 where appropriate.
102
103 * In the schematic diagrams that explain non-fast-forward commits,
104 git-multimail shows the names of the branches involved.
105
106 * The emails generated by git-multimail include the name of the Git
107 repository that was modified; this is convenient for recipients who
108 are monitoring multiple repositories.
109
110 * git-multimail allows the email "From" addresses to be configured.
111
112 * The recipients lists (multimailhook.mailinglist,
113 multimailhook.refchangelist, multimailhook.announcelist, and
114 multimailhook.commitlist) can be comma-separated values and/or
115 multivalued settings in the config file; e.g.,
116
117 [multimailhook]
118 mailinglist = mr.brown@example.com, mr.black@example.com
119 announcelist = Him <him@example.com>
120 announcelist = Jim <jim@example.com>
121 announcelist = pop@example.com
122
123 This might make it easier to maintain short recipients lists without
124 requiring full-fledged mailing list software.
125
126 * By default, git-multimail sets email "Reply-To" headers to reply to
127 the pusher (for reference updates) and to the author (for commit
128 notifications). By default, the pusher's email address is
129 constructed by appending "multimailhook.emaildomain" to the pusher's
130 username.
131
132 * The generated emails contain a configurable footer. By default, it
133 lists the name of the administrator who should be contacted to
134 unsubscribe from notification emails.
135
136 * New option multimailhook.emailmaxlinelength to limit the length of
137 lines in the main part of the email body. The default limit is 500
138 characters.
139
140 * New option multimailhook.emailstrictutf8 to ensure that the main
141 part of the email body is valid UTF-8. Invalid characters are
142 turned into the Unicode replacement character, U+FFFD. By default
143 this option is turned on.
144
145 * Written in Python. Easier to add new features.