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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-15 17:54:12 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-15 17:54:12 +0000 |
commit | b527294153be3b79563c82c66102adc0004736c0 (patch) | |
tree | 9b423a224848441885190b5ea7cf0feb23510c9d /contrib/slapd-modules/variant/slapo-variant.5 | |
parent | Initial commit. (diff) | |
download | openldap-b527294153be3b79563c82c66102adc0004736c0.tar.xz openldap-b527294153be3b79563c82c66102adc0004736c0.zip |
Adding upstream version 2.6.7+dfsg.upstream/2.6.7+dfsg
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'contrib/slapd-modules/variant/slapo-variant.5')
-rw-r--r-- | contrib/slapd-modules/variant/slapo-variant.5 | 472 |
1 files changed, 472 insertions, 0 deletions
diff --git a/contrib/slapd-modules/variant/slapo-variant.5 b/contrib/slapd-modules/variant/slapo-variant.5 new file mode 100644 index 0000000..f46eb69 --- /dev/null +++ b/contrib/slapd-modules/variant/slapo-variant.5 @@ -0,0 +1,472 @@ +.TH SLAPO-VARIANT 5 "RELEASEDATE" "OpenLDAP" +.\" Copyright 2016-2017 Symas Corp. All Rights Reserved. +.\" Copying restrictions apply. See LICENSE. +.SH NAME +slapo\-variant \- share values between entries +.SH SYNOPSIS +olcOverlay=variant +.SH DESCRIPTION +The +.B variant +overlay to +.BR slapd (8) +allows attributes/values to be shared between several entries. In some ways +this is similar to +.BR slapo-collect (5) +with the exception that the source and target attributes can be different. +.LP +The overlay operates on configured +.B variant +entries which can have several +.B attributes +each configured to borrow values from an attribute in the +.B alternate +entry. +.LP +Two types of +.B variant +entries can be configured, +.B regular +and +.BR regex , +where the latter are configured with a regular expression and patterns to +locate each alternate entry, with access to the variant DN and first nine +submatches captured by the regular expression. +.LP +For most purposes (see +.BR LIMITATIONS , +especially for +.B regex +variants), the resulting entry is completely transparent to the operations +performed on it, e.g. a modify operation on the +.B variant +attribute gets transformed +into an operation on the +.B alternate +entry+attribute. As such, the usual ACL rules apply, appropriate +access to both the +.B variant +and +.B alternate +entry is checked. +.LP +As a special case, +.B Add +and +.B Delete +operations will not affect the +.B alternate +entries. Should an attempt be made to add a configured +.B variant +entry with the +.B variant +attributes already populated, the operation will be rejected with a +.B Constraint +.BR Violation . + +.SH CONFIGURATION LAYOUT + +The overlay has to be instantiated under a database adding an entry of +.B olcOverlay=variant +with objectClass of +.BR olcVariantConfig . + +The overlay configuration subtree consists of the following levels: +.RS +.TP +.B objectClass=olcVariantConfig +Main overlay configuration. Created directly under the database +configuration entry. +.TP +.B objectClass=olcVariantVariant +Specifies a +.B regular variant +entry and must be a child of an entry with +.BR objectClass=olcVariantConfig . +There may be as many such entries as necessary provided they all specify a +different DN in the +.BR olcVariantEntry +attribute. +.TP +.B objectClass=olcVariantAttribute +Specifies a +.B regular variant +attribute together with information where the +.B alternate +attribute is stored. Must be a child of an entry with +.BR objectClass=olcVariantVariant . +There may be as many such entries as necessary provided they all specify a +different attribute in +.BR olcVariantVariantAttribute . +.TP +.B objectClass=olcVariantRegex +Specifies a +.B regex variant +entry and must be a child of an entry with +.BR objectClass=olcVariantConfig . +There may be as many such entries as necessary provided they all specify a +different DN in the +.BR olcVariantEntryRegex +attribute. +.TP +.B objectClass=olcVariantAttributePattern +Specifies a +.B regex variant +attribute together with information where the +.B alternate +attribute is stored. Must be a child of an entry with +.BR objectClass=olcVariantRegex . +There may be as many such entries as necessary provided they all specify a +different attribute in +.BR olcVariantVariantAttribute . +.RE + +In the case of +.BR slapd.conf (5), +the variant definition is delimited by the keyword +.B variantDN +followed by an arbitrary number of +.B variantSpec +providing the attribute definitions following it. Each new +.B variantDN +line starts configuring a new variant. + +.SH OVERLAY CONFIGURATION ENTRY + +The top entry +.RB ( olcVariantConfig ) +has the following options available: + +.RS +.TP +.B olcVariantPassReplication: TRUE | FALSE +If set to +.BR TRUE , +.B search +operations with the +.B SyncReplication +control will be passed unchanged so that replication can be unaffected. +Defaults to +.B FALSE +while unset. The +.BR slapd.conf (5) +equivalent is +.BR passReplication . +.RE + +.SH VARIANT CONFIGURATION ENTRY + +The +.B regular variant entry +configuration +.RB ( olcVariantVariant ) +has the following options available: + +.RS +.TP +.B olcVariantEntry: <dn> +Mandatory attribute, indicates that the named entry is to be treated as a +.B variant +entry. The +.BR slapd.conf (5) +equivalent is +.BR variantDN . +.TP +.B name: <reference> +Name of the entry for reference, usually the attribute present in the +configuration entry's RDN. There is no +.BR slapd.conf (5) +equivalent as this has no effect on the overlay operation. +.RE + +Similarly, the +.B regex variant entry +configuration +.RB ( olcVariantRegex ) +has these options available: + +.RS +.TP +.B olcVariantRegex: <regex> +Mandatory attribute, indicates that the entries whose normalised DN matches is +to be treated as a +.B regex variant +entry. The (POSIX.2) regex can use submatches to capture parts of the DN for +later use in locating the +.B alternative +.BR entry . +The +.BR slapd.conf (5) +equivalent is +.BR variantRegex . +.TP +.B name: <reference> +Name of the entry for reference, usually the attribute present in the +configuration entry's RDN. There is no +.BR slapd.conf (5) +equivalent as this has no effect on the overlay operation. +.RE + +.SH CONFIGURATION PRECEDENCE + +While several +.B regex variants +can match the same entry, only one can apply at a time. The list of the +.B regular variants +is checked first. Should none match, the list of +.B regex variants +is checked in the order they have been configured using only the first one that +matches. + +.SH VARIANT ATTRIBUTE CONFIGURATION ENTRY + +The +.B regular variant +attribute configuration +.RB ( olcVariantAttribute ) +and +.B regex variant +attribute configuration +.RB ( olcVariantAttributePattern ) +have the following options available: + +.RS +.TP +.B name: <reference> +Name of the attribute configuration for reference and/or documentation, if +present, usually found in the configuration entry's RDN. There is no +.BR slapd.conf (5) +equivalent as this has no effect on the overlay operation. +.TP +.B olcVariantVariantAttribute: <attr> +Mandatory attribute, indicates that the named attribute is not present in +the +.B variant +entry but is to be retrieved from the +.B alternate +entry. +.TP +.B olcVariantAlternativeAttribute: <attr> +Mandatory attribute, indicates that the values of the named attribute is to +be retrieved from the +.B alternate +entry for use as the values of the +.B variant +attribute. The syntaxes of the corresponding +.B variant +and +.B alternate +attributes have to match or the configuration will be rejected. +.TP +.B olcVariantAlternativeEntry: <dn> +Attribute mandatory for +.B regular +.BR variants , +indicates the +.B alternate +entry to use when retrieving the attribute from. +.TP +.B olcVariantAlternativeEntryPattern: <pattern> +Attribute mandatory for +.B regex +.BR variants , +indicates the +.B alternate +entry to use when retrieving the attribute from. Substitution patterns +.RB ( $n ) +can be used to insert parts of the variant entry's DN. +.B $0 +will place the entire variant DN, +.B $1 +to +.B $9 +can be used to place respective capture patterns from the +.B variant +entry. +.TP +.B variantSpec <attr> <attr2> <dn> +.BR slapd.conf (5) +only. The equivalent to options above, where +.B <attr> +represents the +.BR olcVariantVariantAttribute , +.B <attr2> +represents the +.B olcVariantAlternativeAttribute +and +.B <dn> +has the same meaning as the content of +.BR olcVariantAlternativeEntry . +Has to follow a +.B variantDN +line in the overlay's configuration. +.TP +.B variantRegexSpec <attr> <attr2> <pattern> +.BR slapd.conf (5) +only. The equivalent to options above, where +.B <attr> +represents the +.BR olcVariantVariantAttribute , +.B <attr2> +represents the +.B olcVariantAlternativeAttribute +and +.B <pattern> +has the same meaning as the content of +.BR olcVariantAlternativeEntryPattern . +Has to follow a +.B variantRegex +line in the overlay's configuration. +.RE + +.SH EXAMPLE + +The following is an example of a configured overlay, substitute +.B $DATABASE +for the DN of the database it is attached to and +.B {x} +with the desired position of the overlay in the overlay stack. + +.nf +dn: olcOverlay={x}variant,$DATABASE +objectClass: olcVariantConfig +olcOverlay: variant +# Let replication requests pass through unmodified +olcVariantPassReplication: TRUE + +# when an operation considers dc=example,dc=com +dn: name=example,olcOverlay={x}variant,$DATABASE +objectClass: olcVariantVariant +olcVariantEntry: dc=example,dc=com + +# share the Headquarters' address as the company address +dn: olcVariantVariantAttribute=postaladdress,name={0}example,olcOverlay={x}variant,$DATABASE +objectClass: olcVariantAttribute +olcVariantVariantAttribute: postaladdress +olcVariantAlternativeAttribute: postaladdress +olcVariantAlternativeEntry: ou=Headquarters,dc=example,dc=com + +# populate telephonenumber from CEO's home phone +dn: name=Take phone from CEO entry,name={0}example,olcOverlay={x}variant,$DATABASE +objectClass: olcVariantAttribute +olcVariantVariantAttribute: telephonenumber +olcVariantAlternativeAttribute: homephone +olcVariantAlternativeEntry: cn=John Doe,ou=People,dc=example,dc=com + +# Match all entries with example in the DN +# +# It will not match dc=example,dc=com as that's already configured as a regular +# variant +dn: name=example 2,olcOverlay={x}variant,$DATABASE +objectClass: olcVariantRegex +olcVariantEntryRegex: .*example[^,]*,(.*) + +dn: olcVariantVariantAttribute=location,name={1}example 2,olcOverlay={x}variant,$DATABASE +objectClass: olcVariantAttributePattern +olcVariantVariantAttribute: location +olcVariantAlternativeAttribute: location +olcVariantAlternativeEntryPattern: ou=object with location,$1 +.fi + +The +.BR slapd.conf (5) +equivalent of the above follows (note that the converted +.B cn=config +will differ in the first variant attribute configuration entry): + +.nf +overlay variant +passReplication TRUE + +variantDN dc=example,dc=com +variantSpec telephonenumber homephone "cn=John Doe,ou=People,dc=example,dc=com" +variantSpec postaladdress postaladdress ou=Headquarters,dc=example,dc=com + +variantRegex .*example[^,]*,(.*) +variantRegexSpec location location "ou=object with location,$1" +.fi + +.SH REPLICATION + +There are two ways that a database with +.BR slapo-variant (5) +might be replicated, either replicating the data as stored in the database, +or as seen by the clients interacting with the server. + +The former can be achieved by setting the overlay option +.B olcVariantPassReplication +on the provider and configuring +.BR slapo-syncprov (5) +to appear before (with a lower index than) +.BR slapo-variant (5). +This is the preferred way and the only to work with +.B regex variants +or support multi-provider replication, +but care must be taken to configure +.BR slapo-variant (5) +correctly on each replica. + +The latter is mostly possible by keeping the option +.B olcVariantPassReplication +set to +.B FALSE +on the provider and configuring +.BR slapo-syncprov (5) +to appear after (with a higher index than) +.BR slapo-variant (5). +However, it will only really work for replication set-ups that do not +utilise +.B regex +.BR variants , +delta-replication nor the refresh and persist mode and is therefore +discouraged. + +.SH LIMITATIONS +For +.B regex +.BR variants , +the +.B Search +operation will only apply if the search scope is set to +.BR base . + +The +.B ModRDN +operation is not currently handled and will always modify only the entry in +question, not the configured +.B alternate +entry. + +The +.B Modify +operation is not atomic with respect to the alternate entries. Currently, +the overlay processes the operations on the entry, sends the result message +and, if successful, starts modifying the +.B alternate +entries accordingly. +There is currently no support to indicate whether modifications to the +.B alternate +entries have been successful or whether they have finished. + +The only control explicitly handled is the +.B SyncReplication +control if enabled through the +.B olcVariantPassReplication +setting, adding any controls to an operation that is handled by the overlay +might lead to unexpected behaviour and is therefore discouraged. + +.SH FILES +.TP +ETCDIR/slapd.conf +default slapd configuration file +.TP +ETCDIR/slapd.d +default slapd configuration directory +.SH SEE ALSO +.BR slapd-config (5), +.BR slapd.conf (5), +.BR slapd.overlays (5), +.BR regex (7), +.BR slapd (8) +.SH ACKNOWLEDGEMENTS +This module was developed in 2016-2017 by Ondřej Kuzník for Symas Corp. |