MONGODB_TABLE(5) File Formats Manual MONGODB_TABLE(5)
NAME
mongodb_table - Postfix MongoDB client configuration
SYNOPSIS
postmap -q "string" mongodb:/etc/postfix/filename
postmap -q - mongodb:/etc/postfix/filename <inputfile
DESCRIPTION
The Postfix mail system uses optional tables for address rewriting or
mail routing. These tables are usually in dbm or db format.
Alternatively, lookup tables can be specified as MongoDB databases. In
order to use MongoDB lookups, define a MongoDB source as a lookup table
in main.cf, for example:
alias_maps = mongodb:/etc/postfix/mongodb-aliases.cf
In this example, the file /etc/postfix/mongodb-aliases.cf has the same
format as the Postfix main.cf file, and can specify the parameters de-
scribed below. It is also possible to have the configuration in main.cf;
see "OBSOLETE MAIN.CF PARAMETERS" below.
It is strongly recommended to use proxy:mongodb, in order to reduce the
number of database connections. For example:
alias_maps = proxy:mongodb:/etc/postfix/mongodb-aliases.cf
Note: when using proxy:mongodb:/file, the file must be readable by the
unprivileged postfix user (specified with the Postfix mail_owner config-
uration parameter).
MONGODB PARAMETERS
uri The URI of mongo server/cluster that Postfix will try to connect
to and query from. Please see
https://www.mongodb.com/docs/manual/reference/connection-string/
Example:
uri = mongodb+srv://user:pass@loclhost:27017/mail
dbname Name of the database to read the information from. Example:
dbname = mail
collection
Name of the collection (table) to read the information from. Ex-
ample:
collection = mailbox
query_filter
The MongoDB query template used to search the database, where %s
is a substitute for the email address that Postfix is trying to
resolve. Please see:
https://www.mongodb.com/docs/manual/tutorial/query-documents/
Example:
query_filter = {"$or": [{"username": "%s"}, {"alias.address": "%s"}], "active": 1}
This parameter supports the following '%' expansions:
%% This is replaced by a literal '%' character.
%s This is replaced by the input key. The %s must appear in
quotes, because all Postfix queries are strings containing
(parts from) a domain or email address. Postfix makes no
numerical queries.
%u When the input key is an address of the form user@domain,
%u is replaced by the local part of the address. Other-
wise, %u is replaced by the entire search string.
%d When the input key is an address of the form user@domain,
%d is replaced by the domain part of the address.
%[1-9] The patterns %1, %2, ... %9 are replaced by the corre-
sponding most significant component of the input key's do-
main. If the input key is user@mail.example.com, then %1
is com, %2 is example and %3 is mail.
In the above substitutions, characters will be quoted as required
by RFC 4627. For example, each double quote or backslash charac-
ter will be escaped with a backslash characacter.
projection
Advanced MongoDB query projections. Please see:
https://www.mongodb.com/docs/manual/tutorial/project-fields-from-query-results/
• If projection is non-empty, then result_attribute must be
empty.
• This implementation can extract information only from re-
sult fields that have type string (UTF8), integer (int32,
int64) and array. Other result fields will be ignored with
a warning. Please see:
https://mongoc.org/libbson/current/bson_type_t.html
• As with result_attribute, the top-level _id field (type
OID) is automatically removed from projection results.
result_attribute
Comma or whitespace separated list with the names of fields to be
returned in a lookup result.
• If result_attribute is non-empty, then projection must be
empty.
• As with projection, the top-level _id field (type OID) is
automatically removed from lookup results.
result_format (default: %s)
Format template applied to the result from projection or re-
sult_attribute. Most commonly used to append (or prepend) text to
the result. This parameter supports the following '%' expansions:
%% This is replaced by a literal '%' character.
%s This is replaced by the value of the result attribute.
When result is empty it is skipped.
%u When the result attribute value is an address of the form
user@domain, %u is replaced by the local part of the ad-
dress. When the result has an empty localpart it is
skipped.
%d When a result attribute value is an address of the form
user@domain, %d is replaced by the domain part of the at-
tribute value. When the result is unqualified it is
skipped.
%[SUD1-9]
The upper-case and decimal digit expansions interpolate
the parts of the input key rather than the result. Their
behavior is identical to that described with query_filter,
and in fact because the input key is known in advance,
lookups whose key does not contain all the information
specified in the result template are suppressed and return
no results.
For example, using "result_format = smtp:[%s]" allows one to use
a mailHost attribute as the basis of a transport(5) table. After
applying the result format, multiple values are concatenated as
comma separated strings. The expansion_limit parameter explained
below allows one to restrict the number of values in the result,
which is especially useful for maps that should return a single
value.
The default value %s specifies that each attribute value should
be used as is.
NOTE: DO NOT put quotes around the result format! The result is
not a JSON string.
domain (default: no domain list)
This is a list of domain names, paths to files, or "type:table"
databases. When specified, only fully qualified search keys with
a *non-empty* localpart and a matching domain are eligible for
lookup: 'user' lookups, bare domain lookups and "@domain" lookups
are not performed. This can significantly reduce the query load
on the backend database. Example:
domain = postfix.org, hash:/etc/postfix/searchdomains
expansion_limit (default: 0)
A limit on the total number of result elements returned (as a
comma separated list) by a lookup against the map. A setting of
zero disables the limit. Lookups fail with a temporary error if
the limit is exceeded. Setting the limit to 1 ensures that
lookups do not return multiple values.
OBSOLETE MAIN.CF PARAMETERS
MongoDB parameters can also be defined in main.cf. Specify as MongoDB
source a name that doesn't begin with a slash or a dot. The MongoDB pa-
rameters will then be accessible as the name you've given the source in
its definition, an underscore, and the name of the parameter. For exam-
ple, if a map is specified as "mongodb:mongodb_source", the "uri" para-
meter would be defined in main.cf as "mongodb_source_uri".
Note: with this form, passwords are written in main.cf, which is nor-
mally world-readable, and '$' in a mongodb parameter setting needs to be
written as '$$'.
SEE ALSO
postmap(1), Postfix lookup table maintenance
postconf(5), configuration parameters
README FILES
Use "postconf readme_directory" or "postconf html_directory" to locate
this information.
DATABASE_README, Postfix lookup table overview
MONGODB_README, Postfix MONGODB client guide
LICENSE
The Secure Mailer license must be distributed with this software.
HISTORY
MongoDB support was introduced with Postfix version 3.9.
AUTHOR(S)
Hamid Maadani (hamid@dexo.tech)
Dextrous Technologies, LLC
Edited by:
Wietse Venema
porcupine.org
Based on prior work by:
Stephan Ferraro
Aionda GmbH
MONGODB_TABLE(5)
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