4. Namespace Conventions 4.1. Dataset Namespace The dataset namespace is a slash-separated hierarchy. The first component of the dataset namespace is a dataset class. Dataset classes MUST have a vendor prefix (vendor.<vendor/product>) or be specified in a standards track or IESG approved experimental RFC. See section 7.3 for the registration template. The second component of the dataset name is "site", "group", "host", or "user" referring to server-wide data, administrative group data, per-host data and per-user data respectively. For "group", "host", and "user" areas, the third component of the path is the group name, the fully qualified host domain name, or the user name. A path of the form "/<dataset-class>/~/" is a convenient abbreviation for "/<dataset-class>/user/<current-user>/". Dataset names which begin with "/byowner/" are reserved as an alternate view of the namespace. This provides a way to see all the dataset classes which a particular owner uses. For example, "/byowner/~/<dataset-class>/" is an alternate name for "/<dataset-class>/~/". Byowner provides a way to view a list of dataset classes owned by a given user; this is done using the dataset "/byowner/user/<current-user>/" with the NOINHERIT SEARCH modifier. The dataset "/" may be used to find all dataset classes visible to the current user. A dataset of the form "/<dataset-class>/user/" may be used to find all users which have made a dataset or entry of that class visible to the current user. The formal syntax for a dataset name is defined by the "dataset-name" rule in section 4.3. 4.2. Attribute Namespace Attribute names which do not contain a dot (".") are reserved for standardized attributes which have meaning in any dataset. In order to simplify client implementations, the attribute namespace is intended to be unique across all datasets. To achieve this, attribute names are prefixed with the dataset class name followed by a dot ("."). Attributes which affect management of the dataset are prefixed with "dataset.". In addition, a subtree of the "vendor." attribute namespace may be registered with IANA according to the rules in section 7.4. ACAP implementors are encouraged to help define interoperable dataset classes specifications rather than using the private attribute namespace.
Some users or sites may wish to add their own private attributes to certain dataset classes. In order to enable this, the "user.<user- name>." and "site." subtrees of the attribute namespace are reserved for user-specific and site-specific attributes respectively and will not be standardized. Such attributes are not interoperable so are discouraged in favor of defining standard attributes. A future extension is expected to permit discovery of syntax for user or site-specific attributes. Clients wishing to support display of user or site-specific attributes should display the value of any non-NIL single-valued "user.<user-name>." or "site." attribute which has valid UTF-8 syntax. The formal syntax for an attribute name is defined by the "attribute-name" rule in the next section. 4.3. Formal Syntax for Dataset and Attribute Namespace The naming conventions for datasets and attributes are defined by the following ABNF. Note that this grammar is not part of the ACAP protocol syntax in section 8, as dataset names and attribute names are encoded as strings within the ACAP protocol. attribute-dacl = "dataset.acl" *("." name-component) attribute-dset = dataset-std 1*("." name-component) ;; MUST be defined in a dataset class specification attribute-name = attribute-std / attr-site / attr-user / vendor-name attribute-std = "entry" / "subdataset" / "modtime" / "dataset.inherit" / attribute-dacl / attribute-dset attr-site = "site" 1*("." name-component) attr-user = "user." name-component 1*("." name-component) byowner = "/byowner/" owner "/" [dataset-class "/" dataset-sub] dataset-class = dataset-std / vendor-name dataset-normal = "/" [dataset-class "/" (owner-prefix / dataset-tail)] dataset-name = byowner / dataset-normal
dataset-std = name-component ;; MUST be registered with IANA and the spec MUST ;; be published as a standards track or ;; IESG-approved experimental RFC dataset-sub = *(dname-component "/") ;; The rules for this portion of the namespace may ;; be further restricted by the dataset class ;; specification. dataset-tail = owner "/" dataset-sub dname-component = 1*UTF8-CHAR ;; MUST NOT begin with "." or contain "/" name-component = 1*UTF8-CHAR ;; MUST NOT contain ".", "/", "%", or "*" owner = "site" / owner-host / owner-group / owner-user / "~" owner-group = "group/" dname-component owner-host = "host/" dname-component owner-prefix = "group/" / "host/" / "user/" owner-user = "user/" dname-component vendor-name = vendor-token *("." name-component) vendor-token = "vendor." name-component ;; MUST be registered with IANA 5. Dataset Management The entry with an empty name ("") in the dataset is used to hold management information for the dataset as a whole. 5.1. Dataset Inheritance It is possible for one dataset to inherit data from another. The dataset from which the data is inherited is called the base dataset. Data in the base dataset appears in the inheriting dataset, except when overridden by a STORE to the inheriting dataset.
The base dataset is usually a system-wide or group-wide set of defaults. A system-wide dataset usually has one inheriting dataset per user, allowing each user to add to or modify the defaults as appropriate. An entry which exists in both the inheriting and base dataset inherits a modtime equal to the greater of the two modtimes. An attribute in such an entry is inherited from the base dataset if it was never modified by a STORE command in the inheriting dataset or if DEFAULT was stored to that attribute. This permits default entries to be amended rather than replaced in the inheriting dataset. The "subdataset" attribute is not directly inherited. If the base dataset includes a "subdataset" attribute and the inheriting dataset does not, then the "subdataset" attribute will inherit a virtual value of a list containing a ".". The subdataset at that node is said to be a "virtual" dataset as it is simply a virtual copy of the appropriate base dataset with all "subdataset" attributes changed to a list containing a ".". A virtual dataset is not visible if NOINHERIT is specified on the SEARCH command. Servers MUST support at least two levels of inheritance. This permits a user's dataset such as "/options/user/fred/common" to inherit from a group dataset such as "/options/group/dinosaur operators/common" which in turn inherits from a server-wide dataset such as "/options/site/common". 5.2. Dataset Attributes The following attributes apply to management of the dataset when stored in the "" entry of a dataset. These attributes are not inherited. dataset.acl This holds the default access control list for the dataset. This attribute is validated, so an invalid access control list in a STORE command will result in a NO response with an INVALID response code. dataset.acl.<attribute> This holds the default access control list for an attribute within the dataset. This attribute is validated, so an invalid access control list in a STORE command will result in a NO response with an INVALID response code. dataset.inherit This holds the name of a dataset from which to inherit according to the rules in the previous section. This attribute MAY refer
to a non-existent dataset, in which case nothing is inherited. This attribute is validated, so illegal dataset syntax or an attempt to store a multi-value will result in a NO response with an INVALID response code. 5.3. Dataset Creation When a dataset is first created (by storing a "." in the subdataset attribute or storing an entry in a previously non-existent dataset), the dataset attributes are initialized with the values from the parent dataset in the "/byowner/" hierarchy. In the case of the "dataset.inherit" attribute, the appropriate hierarchy component is added. For example, given the following entry (note that \t refers to the US-ASCII horizontal tab character): entry path "/byowner/user/joe/" dataset.acl ("joe\txrwia" "fred\txr") dataset.inherit "/byowner/site" If a new dataset class "/byowner/user/joe/new" is created, it will have the following dataset attributes: entry path "/byowner/user/joe/new/" dataset.acl ("joe\txrwia" "fred\txr") dataset.inherit "/byowner/site/new" Note that the dataset "/byowner/user/joe/new/" is equivalent to "/new/user/joe/". 5.4. Dataset Class Capabilities Certain dataset classes or dataset class features may only be useful if there is an active updating client or integrated server support for the feature. The dataset class "capability" is reserved to allow clients or servers to advertise such features. The "entry" attribute within this dataset class is the name of the dataset class whose features are being described. The attributes are prefixed with "capability.<dataset-class>." and are defined by the appropriate dataset class specification. Since it is possible for an unprivileged user to run an active client for himself, a per-user capability dataset is useful. The dataset "/capability/~/" holds information about all features available to the user (via inheritance), and the dataset "/capability/site/" holds information about all features supported by the site.
5.5. Dataset Quotas Management and scope of quotas is implementation dependent. Clients can check the applicable quota limit and usage (in bytes) with the GETQUOTA command. Servers can notify the client of a low quota situation with the QUOTA untagged response. 6. Command and Response Specifications ACAP commands and responses are described in this section. Commands are organized first by the state in which the command is permitted, then by a general category of command type. Command arguments, identified by "Arguments:" in the command descriptions below, are described by function, not by syntax. The precise syntax of command arguments is described in the Formal Syntax section. Some commands cause specific server data to be returned; these are identified by "Data:" in the command descriptions below. See the response descriptions in the Responses section for information on these responses, and the Formal Syntax section for the precise syntax of these responses. It is possible for server data to be transmitted as a result of any command; thus, commands that do not specifically require server data specify "no specific data for this command" instead of "none". The "Result:" in the command description refers to the possible tagged status responses to a command, and any special interpretation of these status responses. 6.1. Initial Connection Upon session startup, the server sends one of two untagged responses: ACAP or BYE. The untagged BYE response is described in section 6.2.8. 6.1.1. ACAP Untagged Response Data: capability list The untagged ACAP response indicates the session is ready to accept commands and contains a space-separated listing of capabilities that the server supports. Each capability is represented by a list containing the capability name optionally followed by capability specific string arguments.
ACAP capability names MUST be registered with IANA according to the rules in section 7.1. Client implementations SHOULD NOT require any capability name beyond those defined in this specification, and MUST tolerate any unknown capability names. A client implementation MAY be configurable to require SASL mechanisms other than CRAM-MD5 [CRAM-MD5] for site security policy reasons. The following initial capabilities are defined: CONTEXTLIMIT The CONTEXTLIMIT capability has one argument which is a number describing the maximum number of contexts the server supports per connection. The number 0 indicates the server has no limit, otherwise this number MUST be greater than 100. IMPLEMENTATION The IMPLEMENTATION capability has one argument which is a string describing the server implementation. ACAP clients MUST NOT alter their behavior based on this value. It is intended primarily for debugging purposes. SASL The SASL capability includes a list of the authentication mechanisms supported by the server. See section 6.3.1. Example: S: * ACAP (IMPLEMENTATION "ACME v3.5") (SASL "CRAM-MD5") (CONTEXTLIMIT "200") 6.2. Any State The following commands and responses are valid in any state. 6.2.1. NOOP Command Arguments: none Data: no specific data for this command (but see below) Result: OK - noop completed BAD - command unknown or arguments invalid The NOOP command always succeeds. It does nothing. It can be used to reset any inactivity auto-logout timer on the server. Example: C: a002 NOOP
S: a002 OK "NOOP completed" 6.2.2. LANG Command Arguments: list of language preferences Data: intermediate response: LANG Result: OK - lang completed NO - no matching language available BAD - command unknown or arguments invalid One or more arguments are supplied to indicate the client's preferred languages [LANG-TAGS] for error messages. The server will match each client preference in order against its internal table of available error string languages. For a client preference to match a server language, the client's language tag MUST be a prefix of the server's tag and match up to a "-" or the end of string. If a match is found, the server returns an intermediate LANG response and an OK response. The LANG response indicates the actual language selected and appropriate comparators for use with the languages listed in the LANG command. If no LANG command is issued, all error text strings MUST be in the registered language "i-default" [CHARSET-LANG-POLICY], intended for an international audience. Example: C: A003 LANG "fr-ca" "fr" "en-ca" "en-uk" S: A003 LANG "fr-ca" "i;octet" "i;ascii-numeric" "i;ascii-casemap" "en;primary" "fr;primary" S: A003 OK "Bonjour" 6.2.3. LANG Intermediate Response Data: language for error responses appropriate comparators The LANG response indicates the language which will be used for error responses and the comparators which are appropriate for the languages listed in the LANG command. The comparators SHOULD be in approximate order from most efficient (usually "i;octet") to most appropriate for human text in the preferred language.
6.2.4. LOGOUT Command Arguments: none Data: mandatory untagged response: BYE Result: OK - logout completed BAD - command unknown or arguments invalid The LOGOUT command informs the server that the client is done with the session. The server must send a BYE untagged response before the (tagged) OK response, and then close the network connection. Example: C: A023 LOGOUT S: * BYE "ACAP Server logging out" S: A023 OK "LOGOUT completed" (Server and client then close the connection) 6.2.5. OK Response Data: optional response code human-readable text The OK response indicates an information message from the server. When tagged, it indicates successful completion of the associated command. The human-readable text may be presented to the user as an information message. The untagged form indicates an information-only message; the nature of the information MAY be indicated by a response code. Example: S: * OK "Master ACAP server is back up" 6.2.6. NO Response Data: optional response code human-readable text The NO response indicates an operational error message from the server. When tagged, it indicates unsuccessful completion of the associated command. The untagged form indicates a warning; the command may still complete successfully. The human-readable text describes the condition. Example: C: A010 SEARCH "/addressbook/" DEPTH 3 RETURN ("*") EQUAL "entry" "+i;octet" "bozo" S: * NO "Master ACAP server is down, your data may
be out of date." S: A010 OK "search done" ... C: A222 STORE ("/folder/site/comp.mail.misc" "folder.creation-time" "19951206103412") S: A222 NO (PERMISSION ("/folder/site/")) "Permission denied" 6.2.7. BAD Response Data: optional response code human-readable text The BAD response indicates an error message from the server. When tagged, it reports a protocol-level error in the client's command; the tag indicates the command that caused the error. The untagged form indicates a protocol-level error for which the associated command can not be determined; it may also indicate an internal server failure. The human-readable text describes the condition. Example: C: ...empty line... S: * BAD "Empty command line" C: A443 BLURDYBLOOP S: A443 BAD "Unknown command" C: A444 NOOP Hello S: A444 BAD "invalid arguments" 6.2.8. BYE Untagged Response Data: optional response code human-readable text The untagged BYE response indicates that the server is about to close the connection. The human-readable text may be displayed to the user in a status report by the client. The BYE response may be sent as part of a normal logout sequence, or as a panic shutdown announcement by the server. It is also used by some server implementations as an announcement of an inactivity auto- logout. This response is also used as one of two possible greetings at session startup. It indicates that the server is not willing to accept a session from this client. Example: S: * BYE "Auto-logout; idle for too long"
6.2.9. ALERT Untagged Response Data: optional response code human-readable text The human-readable text contains a special human generated alert message that MUST be presented to the user in a fashion that calls the user's attention to the message. This is intended to be used for vital messages from the server administrator to the user, such as a warning that the server will soon be shut down for maintenance. Example: S: * ALERT "This ACAP server will be shut down in 10 minutes for system maintenance." 6.3. Non-Authenticated State In non-authenticated state, the AUTHENTICATE command establishes authentication and enters authenticated state. The AUTHENTICATE command provides a general mechanism for a variety of authentication techniques. Server implementations may allow non-authenticated access to certain information by supporting the SASL ANONYMOUS [SASL-ANON] mechanism. Once authenticated (including as anonymous), it is not possible to re-enter non-authenticated state. Only the any-state commands (NOOP, LANG and LOGOUT) and the AUTHENTICATE command are valid in non-authenticated state. 6.3.1. AUTHENTICATE Command Arguments: SASL mechanism name optional initial response Data: continuation data may be requested Result: OK - authenticate completed, now in authenticated state NO - authenticate failure: unsupported authentication mechanism, credentials rejected BAD - command unknown or arguments invalid, authentication exchange cancelled
The AUTHENTICATE command indicates a SASL [SASL] authentication mechanism to the server. If the server supports the requested authentication mechanism, it performs an authentication protocol exchange to authenticate and identify the user. Optionally, it also negotiates a security layer for subsequent protocol interactions. If the requested authentication mechanism is not supported, the server rejects the AUTHENTICATE command by sending a tagged NO response. The authentication protocol exchange consists of a series of server challenges and client answers that are specific to the authentication mechanism. A server challenge consists of a command continuation request with the "+" token followed by a string. The client answer consists of a line consisting of a string. If the client wishes to cancel an authentication exchange, it should issue a line with a single unquoted "*". If the server receives such an answer, it must reject the AUTHENTICATE command by sending a tagged BAD response. The optional initial-response argument to the AUTHENTICATE command is used to save a round trip when using authentication mechanisms that are defined to send no data in the initial challenge. When the initial-response argument is used with such a mechanism, the initial empty challenge is not sent to the client and the server uses the data in the initial-response argument as if it were sent in response to the empty challenge. If the initial-response argument to the AUTHENTICATE command is used with a mechanism that sends data in the initial challenge, the server rejects the AUTHENTICATE command by sending a tagged NO response. The service name specified by this protocol's profile of SASL is "acap". If a security layer is negotiated through the SASL authentication exchange, it takes effect immediately following the CRLF that concludes the authentication exchange for the client, and the CRLF of the tagged OK response for the server. All ACAP implementations MUST implement the CRAM-MD5 SASL mechanism [CRAM-MD5], although they MAY offer a configuration option to disable it if site security policy dictates. The example below is the same example described in the CRAM-MD5 specification. If an AUTHENTICATE command fails with a NO response, the client may try another authentication mechanism by issuing another AUTHENTICATE command. In other words, the client may request authentication types in decreasing order of preference.
Example: S: * ACAP (IMPLEMENTATION "Blorfysoft v3.5") (SASL "CRAM-MD5" "KERBEROS_V4") C: A001 AUTHENTICATE "CRAM-MD5" S: + "<firstname.lastname@example.org>" C: "tim b913a602c7eda7a495b4e6e7334d3890" S: A001 OK "CRAM-MD5 authentication successful" 6.4. Searching This section describes the SEARCH command, for retrieving data from datasets. 6.4.1. SEARCH Command Arguments: dataset or context name optional list of modifiers search criteria Data: intermediate responses: ENTRY, MODTIME, REFER untagged responses: ADDTO, REMOVEFROM, CHANGE, MODTIME Result: OK - search completed NO - search failure: can't perform search BAD - command unknown or arguments invalid The SEARCH command identifies a subset of entries in a dataset and returns information on that subset to the client. Inherited entries and attributes are included in the search unless the NOINHERIT search modifier is included or the user does not have permission to read the attributes in the base dataset. The first argument to SEARCH identifies what is to be searched. If the string begins with a slash ("/"), it is the name of a dataset to be searched, otherwise it is a name of a context that was created by a SEARCH command given previously in the session. A successful SEARCH command MAY result in intermediate ENTRY responses and MUST result in a MODTIME intermediate response. Following that are zero or more modifiers to the search. Each modifier may be specified at most once. The defined modifiers are:
DEPTH number The SEARCH command will traverse the dataset tree up to the specified depth. ENTRY responses will include the full path to the entry. A value of "0" indicates that the search should traverse the entire tree. A value of "1" is the default and indicates only the specified dataset should be searched. If a dataset is traversed which is not located on the current server, then a REFER intermediate response is returned for that subtree and the search continues. HARDLIMIT number If the SEARCH command would result in more than number entries, the SEARCH fails with a NO completion result with a WAYTOOMANY response code. LIMIT number number Limits the number of intermediate ENTRY responses that the search may generate. The first numeric argument specifies the limit, the second number specifies the number of entries to return if the number of matches exceeds the limit. If the limit is exceeded, the SEARCH command still succeeds, returning the total number of matches in a TOOMANY response code in the tagged OK response. MAKECONTEXT [ENUMERATE] [NOTIFY] context Causes the SEARCH command to create a context with the name given in the argument to refer to the matching entries. If the SEARCH is successful, the context name may then be given as an argument to subsequent SEARCH commands to search the set of matching entries. If a context with the specified name already exists, it is first freed. If a new context may not be created due to the server's limit on the number of existing contexts, the command fails, returning a TRYFREECONTEXT response code in the NO completion response. The optional "ENUMERATE" and "NOTIFY" arguments may be included to request enumeration of the context (for virtual scroll bars) or change notifications for the context. If "NOTIFY" is not requested, the context represents a snapshot of the entries at the time the SEARCH was issued. ENUMERATE requests that the contents of the context be ordered according to the SORT modifier and that sequential numbers, starting with one, be assigned to the entries in the context. This permits the RANGE modifier to be used to fetch portions of the ordered context.
NOTIFY requests that the server send untagged ADDTO, REMOVEFROM, CHANGE, and MODTIME responses while the context created by this SEARCH command exists. The server MAY issue untagged ADDTO, REMOVEFROM, CHANGE and MODTIME notifications for a context at any time between the issuing of the SEARCH command with MAKECONTEXT NOTIFY and the completion of a FREECONTEXT command for the context. Notifications are only issued for changes which occur after the server receives the SEARCH command which created the context. After issuing a sequence of ADDTO, REMOVEFROM or CHANGE notifications, the server MUST issue an untagged MODTIME notification indicating that the client has all updates to the entries in the context up to and including the given modtime value. Servers are permitted a reasonable delay to batch change notifications before sending them to the client. The position arguments of the ADDTO, REMOVEFROM and CHANGE notifications are 0 if ENUMERATE is not requested. NOINHERIT This causes the SEARCH command to operate without inheritance. It can be used to tell which values are explicit overrides. If MAKECONTEXT is also specified, the created context is also not affected by inheritance. RETURN (metadata...) Specifies what is to be returned in intermediate ENTRY responses. If this modifier is not specified, no intermediate ENTRY responses are returned. Inside the parentheses is an optional list of attributes, each optionally followed by a parenthesized list of metadata. If the parenthesized list of metadata is not specified, it defaults to "(value)". An attribute name with a trailing "*" requests all attributes with that prefix. A "*" by itself requests all attributes. If the parenthesized list of metadata is not specified for an attribute with a trailing "*", it defaults to "(attribute value)". Results matching such an attribute pattern are grouped in parentheses. Following the last intermediate ENTRY response, the server returns a single intermediate MODTIME response.
SORT (attribute comparator ...) Specifies the order in which any resulting ENTRY replies are to be returned to the client. The SORT modifier takes as an argument a parenthesized list of one or more attribute/comparator pairs. Attribute lists the attribute to sort on, comparator specifies the name of the collation rule to apply to the values of the attribute. Successive attribute/comparator pairs are used to order two entries only when all preceding pairs indicate the two entries collate the same. If the SORT modifier is used in conjunction with the MAKECONTEXT modifier, the SORT modifier specifies the ordering of entries in the created context. If no SORT modifier is specified, or none of the attribute/comparator pairs indicates an order for the two entries, the server uses the order of the entries that exists in the context or dataset being searched. Following the modifiers is the search criteria. Searching criteria consist of one or more search keys. Search keys may be combined using the AND, and OR search keys. For example, the criteria (the newline is for readability and not part of the criteria): AND COMPARE "modtime" "+i;octet" "19951206103400" COMPARE "modtime" "-i;octet" "19960112000000" refers to all entries modified between 10:34 December 6 1995 and midnight January 12, 1996 UTC. The currently defined search keys are as follows. ALL This matches all entries. AND search-key1 search-key2 Entries that match both search keys. COMPARE attribute comparator value Entries for which the value of the specified attribute collates using the specified comparator the same or later than the specified value. COMPARESTRICT attribute comparator value Entries for which the specified attribute collates using the specified comparator later than the specified value.
EQUAL attribute comparator value Entries for which the value of the attribute is equal to the specified value using the specified comparator. NOT search-key Entries that do not match the specified search key. OR search-key1 search-key2 Entries that match either search key. PREFIX attribute comparator value Entries which begin with the specified value using the specified comparator. If the specified comparator doesn't support substring matching, a BAD response is returned. RANGE start end time Entries which are within the specified range of the enumerated context's ordering. The lowest-ordered entry in the context is assigned number one, the next lowest entry is assigned number two, and so on. The numeric arguments specify the lowest and highest numbers to match. The time specifies that the client has processed notifications for the context up to the specified time. If the context has been modified since then, the server MUST either return a NO with a MODIFIED response code, or return the results that the SEARCH would have returned if none of the changes since that time had been made. RANGE is only permitted on enumerated contexts. If RANGE is used with a dataset or non-enumerated context, the server MUST return a BAD response. SUBSTRING attribute comparator value Entries which contain the specified value, using the specified comparator. If the specified comparator doesn't support substring matching, a BAD response is returned. 6.4.2. ENTRY Intermediate Response Data: entry name entry data The ENTRY intermediate response occurs as a result of a SEARCH or STORE command. This is the means by which dataset entries are returned to the client.
The ENTRY response begins with the entry name, if a SEARCH command without the DEPTH modifier was issued, or the entry path in other cases. This is followed by a set of zero or more items, one for each metadata item in the RETURN search modifier. Results matching an attribute pattern or returning multiple metadata items are grouped in parentheses. 6.4.3. MODTIME Intermediate Response Data: modtime value The MODTIME intermediate response occurs as a result of a SEARCH command. It indicates that the just created context or the previously returned ENTRY responses include all updates to the returned entries up to and including the modtime value in the argument. 6.4.4. REFER Intermediate Response Data: dataset path relative ACAP URLs The REFER intermediate response occurs as a result of a multi-level SEARCH where one of the levels is located on a different server. The response indicates the dataset which is not located on the current server and one or more relative ACAP URLs for where that dataset may be found. 6.4.5. Search Examples Here are some SEARCH command exchanges between the client and server: C: A046 SEARCH "/addressbook/" DEPTH 3 RETURN ("addressbook.Alias" "addressbook.Email" "addressbook.List") OR NOT EQUAL "addressbook.Email" "i;octet" NIL NOT EQUAL "addressbook.List" "i;octet" NIL S: A046 ENTRY "/addressbook/user/joe/A0345" "fred" "email@example.com" NIL S: A046 ENTRY "/addressbook/user/fred/A0537" "joe" "firstname.lastname@example.org" NIL S: A046 ENTRY "/addressbook/group/Dinosaur Operators/A423" "saurians" NIL "1" S: A046 MODTIME "19970728105252" S: A046 OK "SEARCH completed" C: A047 SEARCH "/addressbook/user/fred/" RETURN ("*") EQUAL "entry" "i;octet" "A0345" S: A047 ENTRY "A0345" (("modtime" "19970728102226")
("addressbook.Alias" "fred") ("addressbook.Email" "email@example.com") ("addressbook.CommonName" "Fred Flintstone") ("addressbook.Surname" "Flintstone") ("addressbook.GivenName" "Fred")) S: A047 MODTIME "19970728105258" S: A047 OK "SEARCH completed" C: A048 SEARCH "/options/~/vendor.example/" RETURN ("option.value"("size" "value" "myrights")) SORT ("entry" "i;octet") COMPARE "modtime" "i;octet" "19970727123225" S: A048 ENTRY "blurdybloop" (5 "ghoti" "rwia") S: A048 ENTRY "buckybits" (2 "10" "rwia") S: A048 ENTRY "windowSize" (7 "100x100" "rwia") S: A048 MODTIME "19970728105304" S: A048 OK "SEARCH completed" C: A049 SEARCH "/addressbook/~/public" RETURN ("addressbook.Alias" "addressbook.Email") MAKECONTEXT ENUMERATE "blob" LIMIT 100 1 SORT ("addressbook.Alias" "i;octet") NOT EQUAL "addressbook.Email" NIL S: A049 ENTRY "A437" "aaguy" "firstname.lastname@example.org" S: A049 MODTIME "19970728105308" S: A049 OK (TOOMANY 347) "Context 'blob' created" C: A050 SEARCH "blob" RANGE 2 2 "19970728105308" ALL S: A050 ENTRY "A238" "abguy" "email@example.com" S: A050 MODTIME "19970728105310" S: A050 OK "SEARCH Completed" 6.5. Contexts The following commands use contexts created by a SEARCH command with a MAKECONTEXT modifier. 6.5.1. FREECONTEXT Command Arguments: context name Data: no specific data for this command Result: OK - freecontext completed NO - freecontext failure: no such context BAD - command unknown or arguments invalid
The FREECONTEXT command causes the server to free all state associated with the named context. The context may no longer be searched and the server will no longer issue any untagged responses for the context. The context is no longer counted against the server's limit on the number of contexts. Example: C: A683 FREECONTEXT "blurdybloop" S: A683 OK "Freecontext completed" 6.5.2. UPDATECONTEXT Command Arguments: list of context names Data: untagged responses: ADDTO REMOVEFROM CHANGE MODTIME Result: OK - Updatecontext completed: all updates completed NO - Updatecontext failed: no such context not a notify context BAD - command unknown or arguments invalid The UPDATECONTEXT command causes the server to ensure that the client is notified of all changes known to the server for the contexts listed as arguments up to the current time. The contexts listed in the arguments must have been previously given to a successful SEARCH command with a MAKECONTEXT NOTIFY modifier. A MODTIME untagged response MUST be returned if any read-write metadata in the context changed since the last MODTIME for that context. This includes metadata which is not listed in the RETURN modifier for the context. While a server may issue untagged ADDTO, REMOVEFROM, CHANGE, and MODTIME at any time, the UPDATECONTEXT command is used to "prod" the server to send any notifications it has not sent yet. The UPDATECONTEXT command SHOULD NOT be used to poll for updates. Example: C: Z4S9 UPDATECONTEXT "blurdybloop" "blarfl" S: Z4S9 OK "client has been notified of all changes" 6.5.3. ADDTO Untagged Response Data: context name entry name position metadata list
The untagged ADDTO response informs the client that an entry has been added to a context. The response includes the position number of the added entry (the first entry in the context is numbered 1) and those metadata contained in the entry which match the RETURN statement when the context was created. For enumerated contexts, the ADDTO response implicitly adds one to the position of all members of the context which had position numbers that were greater than or equal to the ADDTO position number. For non-enumerated contexts, the position field is always 0. Example: S: * ADDTO "blurdybloop" "fred" 15 ("addressbook.Email" "firstname.lastname@example.org") 6.5.4. REMOVEFROM Untagged Response Data: context name entry name old position The untagged REMOVEFROM response informs the client that an entry has been removed from a context. The response includes the position number that the removed entry used to have (the first entry in the context is numbered 1). For enumerated contexts, the REMOVEFROM response implicitly subtracts one from the position numbers of all members of the context which had position numbers greater than the REMOVEFROM position number. For non-enumerated contexts, the position field is always 0. Example: S: * REMOVEFROM "blurdybloop" "fred" 15 6.5.5. CHANGE Untagged Response Data: context name entry name old position new position metadata list The untagged CHANGE response informs the client that an entry in a context has either changed position in the context or has changed the values of one or more of the attributes specified in the RETURN modifier when the context was created.
The response includes the previous and current position numbers of the entry (which are 0 if ENUMERATE was not specified on the context) and the attribute metadata requested in the RETURN modifier when the context was created. For enumerated contexts, the CHANGE response implicitly changes the position numbers of all entries which had position numbers between the old and new position. If old position is less than new position, than one is subtracted from all entries which had position numbers in that range. Otherwise one is added to all entries which had position numbers in that range. If the old position and new position are the same, then no implicit position renumbering occurs. CHANGE responses are not issued for entries which have changed position implicitly due to another ADDTO, REMOVEFROM or CHANGE response. Example: S: * CHANGE "blurdybloop" "fred" 15 10 ("addressbook.Email" "email@example.com") 6.5.6. MODTIME Untagged Response Data: context name modtime value The untagged MODTIME response informs the client that it has received all updates to entries in the context which have modtime values less than or equal to the modtime value in the argument. Example: S: * MODTIME mycontext "19970320162338" 6.6. Dataset modification The following commands and responses handle modification of datasets.
6.6.1. STORE Command Arguments: entry store list Data: intermediate responses: ENTRY Result: OK - store completed NO - store failure: can't store that name UNCHANGEDSINCE specified and entry changed BAD - command unknown or arguments invalid invalid UTF-8 syntax in attribute name Creates, modifies, or deletes the named entries in the named datasets. The values of metadata not specified in the command are not changed. Setting the "value" metadata of an attribute to NIL removes that attribute from the entry. Setting the "value" of the "entry" attribute to NIL removes that entry from the dataset and cancels inheritance for the entire entry. Setting the "value" of the "entry" attribute to DEFAULT removes that entry from the inheriting dataset and reverts the entry and its attributes to inherited values, if any. Changing the value of the "entry" attribute renames the entry. Storing DEFAULT to the "value" metadata of an attribute is equivalent to storing NIL, except that inheritance is enabled for that attribute. If a non-NIL value is inherited then an ENTRY intermediate response is generated to notify the client of the this change. The ENTRY response includes the entry-path and the attribute name and value metadata for each attribute which reverted to a non-NIL inherited setting. Storing NIL to the "value" metadata of an attribute MAY be treated equivalent to storing DEFAULT to that "value" if there is a NIL value in the base dataset. The STORE command is followed by one or more entry store lists. Each entry store list begins with an entry path followed by STORE modifiers, followed by zero or more attribute store items. Each attribute store item is made up of the attribute name followed by NIL (to remove the attribute's value), DEFAULT (to revert the item to any inherited value), a single value (to set the attribute's single value), or a list of metadata items to modify. The following STORE modifiers may be specified:
NOCREATE By default, the server MUST create any datasets necessary to store the entry, including multiple hierarchy levels. If NOCREATE is specified, the STORE command will fail with a NOEXIST error unless the parent dataset already exists. UNCHANGEDSINCE If the "modtime" of the entry is later than the unchangedsince time, then the store fails with a MODIFIED response code. Use of UNCHANGEDSINCE with a time of "00000101000000" will always fail if the entry exists. Clients writing to a shared dataset are encouraged to use UNCHANGEDSINCE when modifying an existing entry. The server MUST either make all the changes specified in a single STORE command or make none of them. If successful, the server MUST update the "modtime" attribute for every entry which was changed. It is illegal to list any metadata item within an attribute twice, any attribute within an entry twice or any entry path twice. The server MUST return a BAD response if this happens. The server MAY re-order the strings in a multi-value on STORE and MAY remove duplicate strings. However, SEARCH MUST return multi- values and the associated size list metadata in a consistant order. Example: C: A342 STORE ("/addressbook/user/fred/ABC547" "addressbook.TelephoneNumber" "555-1234" "addressbook.CommonName" "Barney Rubble" "addressbook.AlternateNames" ("value" ("Barnacus Rubble" "Coco Puffs Thief")) "addressbook.Email" NIL) S: A342 OK "Store completed" C: A343 STORE ("/addressbook/user/joe/ABD42" UNCHANGEDSINCE "19970320162338" "user.joe.hair-length" "10 inches") S: A343 NO (MODIFIED) "'ABD42' has been changed by somebody else." C: A344 STORE ("/addressbook/group/Developers/ACD54" "entry" NIL) S: A344 OK "Store completed" C: A345 STORE ("/option/~/common/SMTPserver" "option.value" DEFAULT) S: A345 ENTRY "/option/~/common/SMTPserver"
"option.value" "smtp.server.do.main" S: A345 OK "Store completed" C: A347 STORE ("/addressbook/~/" "dataset.inherit" "/addressbook/group/Developers") S: A347 OK "Store completed" 6.6.2. DELETEDSINCE Command Arguments: dataset name time Data: intermediate response: DELETED Result: OK - DELETEDSINCE completed NO - DELETEDSINCE failure: can't read dataset date too far in the past BAD - command unknown or arguments invalid The DELETEDSINCE command returns in intermediate DELETED replies the names of entries that have been deleted from the named dataset since the given time. Servers may impose a limit on the number or age of deleted entry names they keep track of. If the server does not have information going back to the specified time, the command fails, returning a TOOOLD response code in the tagged NO response. Example: C: Z4S9 DELETEDSINCE "/folder/site/" 19951205103412 S: Z4S9 DELETED "blurdybloop" S: Z4S9 DELETED "anteaters" S: Z4S9 OK "DELETEDSINCE completed" C: Z4U3 DELETEDSINCE "/folder/site/" 19951009040854 S: Z4U3 NO (TOOOLD) "Don't have that information" 6.6.3. DELETED Intermediate Response Data: entry name The intermediate DELETED response occurs as a result of a DELETEDSINCE command. It returns an entry that has been deleted from the dataset specified in the DELETEDSINCE command. 6.7. Access Control List Commands The commands in this section are used to manage access control lists.
6.7.1. SETACL Command Arguments: acl object authentication identifier access rights Data: no specific data for this command Result: OK - setacl completed NO - setacl failure: can't set acl BAD - command unknown or arguments invalid The SETACL command changes the access control list on the specified object so that the specified identifier is granted the permissions enumerated in rights. If the object did not previously have an access control list, one is created. Example: C: A123 SETACL ("/addressbook/~/public/") "anyone" "r" S: A123 OK "Setacl complete" C: A124 SETACL ("/folder/site/") "B1FF" "rwa" S: A124 NO (PERMISSION ("/folder/site/")) "'B1FF' not permitted to modify access rights for '/folder/site/'" 6.7.2. DELETEACL Command Arguments: acl object optional authentication identifier Data: no specific data for this command Result: OK - deleteacl completed NO - deleteacl failure: can't delete acl BAD - command unknown or arguments invalid If given the optional identifier argument, the DELETEACL command removes any portion of the access control list on the specified object for the specified identifier. If not given the optional identifier argument, the DELETEACL command removes the ACL from the object entirely, causing access to be controlled by a higher-level default ACL. This form of the DELETEACL command is not permitted on the default ACL for a dataset and servers MUST return a BAD.
Example: C: A223 DELETEACL ("/addressbook/~/public") "anyone" S: A223 OK "Deleteacl complete" C: A224 DELETEACL ("/folder/site") S: A224 BAD "Can't delete ACL from dataset" C: A225 DELETEACL ("/addressbook/user/fred" "addressbook.Email" "barney") S: A225 OK "Deleteacl complete" 6.7.3. MYRIGHTS Command Arguments: acl object Data: intermediate responses: MYRIGHTS Result: OK - myrights completed NO - myrights failure: can't get rights BAD - command unknown or arguments invalid The MYRIGHTS command returns the set of rights that the client has to the given dataset or dataset attribute. Example: C: A003 MYRIGHTS ("/folder/site") S: A003 MYRIGHTS "r" S: A003 OK "Myrights complete" 6.7.4. MYRIGHTS Intermediate Response Data: rights The MYRIGHTS response occurs as a result of a MYRIGHTS command. The argument is the set of rights that the client has for the object referred to in the MYRIGHTS command. 6.7.5. LISTRIGHTS Command Arguments: acl object authentication identifier Data: untagged responses: LISTRIGHTS Result: OK - listrights completed NO - listrights failure: can't get rights list BAD - command unknown or arguments invalid
The LISTRIGHTS command takes an object and an identifier and returns information about what rights the current user may revoke or grant to that identifier in the ACL for that object. Example: C: a001 LISTRIGHTS ("/folder/~/") "smith" S: a001 LISTRIGHTS "xra" "w" "i" S: a001 OK Listrights completed C: a005 LISTRIGHTS ("/folder/site/archive/imap") "anyone" S: a005 LISTRIGHTS "" "x" "r" "w" "i" S: a005 OK Listrights completed 6.7.6. LISTRIGHTS Intermediate Response Data: required rights list of optional rights The LISTRIGHTS response occurs as a result of a LISTRIGHTS command. The first argument is a string containing the (possibly empty) set of rights the identifier will always be granted on the dataset or attribute. Following this are zero or more strings each containing a single right which the current user may revoke or grant to the identifier in the dataset or attribute. The same right MUST NOT be listed more than once in the LISTRIGHTS response. 6.8. Quotas The section defines the commands and responses relating to quotas. 6.8.1. GETQUOTA Command Arguments: dataset Data: untagged responses: QUOTA Result: OK - Quota information returned NO - Quota failure: can't access resource limit no resource limit BAD - command unknown or arguments invalid
The GETQUOTA command takes the name of a dataset, and returns in an untagged QUOTA response the name of the dataset, quota limit in bytes that applies to that dataset and the quota usage within that limit. The scope of a quota limit is implementation dependent. Example: C: A043 GETQUOTA "/option/user/fred/common" S: * QUOTA "/option/user/fred/common" 1048576 2475 S: A043 OK "Getquota completed" 6.8.3. QUOTA Untagged Response Data: dataset quota limit in bytes amount of quota limit used extension data The QUOTA untagged response is generated as a result of a GETQUOTA command or MAY be generated by the server in response to a SEARCH or STORE command to warn about high usage of a quota. It includes the name of the applicable dataset, the quota limit in bytes, the quota usage and some optional extension data. Clients MUST tolerate the extension data as its use is reserved for a future extension. 6.9. Extensions In order to simplify the process of extending the protocol, clients MUST tolerate unknown server responses which meet the syntax of response-extend. In addition, clients MUST tolerate unknown server response codes which meet the syntax of resp-code-ext. Availability of new commands MUST be announced via a capability on the initial greeting line and such commands SHOULD meet the syntax of command-extend. Servers MUST respond to unknown commands with a BAD command completion result. Servers MUST skip over non-synchronizing literals contained in an unknown command. This may be done by assuming the unknown command matches the command-extend syntax, or by reading a line at a time and checking for the non-synchronizing literal syntax at the end of the line.