From: Sebastian Harl Date: Sat, 2 Aug 2014 21:22:57 +0000 (+0200) Subject: sysdbql(7): Updated documentation to keep up with the latest changes. X-Git-Tag: sysdb-0.4.0~41 X-Git-Url: https://git.tokkee.org/?a=commitdiff_plain;h=a9b9b0c537307cc3c4eaac1fb6c0bf4f29dbf9fc;p=sysdb.git sysdbql(7): Updated documentation to keep up with the latest changes. --- diff --git a/doc/sysdbql.7.txt b/doc/sysdbql.7.txt index f1993cb..aa3add3 100644 --- a/doc/sysdbql.7.txt +++ b/doc/sysdbql.7.txt @@ -9,9 +9,12 @@ sysdbql - the SysDB query language SYNOPSIS -------- - LIST; + LIST hosts; - LOOKUP hosts MATCHING attribute.architecture = 'amd64'; + FETCH host 'some.host.name'; + + LOOKUP hosts MATCHING attribute.architecture = 'amd64' + FILTER :age < 5 * :interval; DESCRIPTION ----------- @@ -27,25 +30,33 @@ QUERY COMMANDS Each command is terminated by a semicolon. The following commands are available to retrieve information from SysDB: -*LIST*:: +*LIST* hosts [*FILTER* '']:: Retrieve a sorted (by name) list of all hosts currently stored in SysDB. The -return value is a list of hosts where each host description includes its name, -the timestamp of the last update of the object in SysDB and an approximation -of the interval with which the host was updated. - -*FETCH* '':: +return value is a list of hosts where each host specification includes its +name, the timestamp of the last update of the object known to SysDB and an +approximation of the interval with which the host was updated. If a filter +condition is specified, only objects matching that filter will be included in +the reply. See the section "FILTER clause" for more details about how to +specify the search and filter conditions. + +*FETCH* host '' [*FILTER* '']:: Retrieve detailed information about the specified host object. The return value includes the hostname, a list of services referenced by the host, and a list of attributes for the host and each service. If the host does not exist, -an error is returned. +an error is returned. If a filter condition is specified, only objects +matching that filter will be included in the reply. See the section "FILTER +clause" for more details about how to specify the search and filter +conditions. *LOOKUP* hosts *MATCHING* '' [*FILTER* '']:: Retrieve detailed information about all host objects matching the specified search condition. The return value is a list of detailed information for each matching host providing the same details as returned by the *FETCH* command. -If a filter condition is specified, only objects matching that filter will be -included in the reply. See the sections "MATCHING clause" and "FILTER clause" -for more details about how to specify the search and filter conditions. +If no host matches the search criteria, it's not considered an error. Instead, +an empty list is returned. If a filter condition is specified, only objects +matching that filter will be included in the reply. See the sections "MATCHING +clause" and "FILTER clause" for more details about how to specify the search +and filter conditions. MATCHING clause ~~~~~~~~~~~~~~~ @@ -80,6 +91,8 @@ The following fields may be queried: *attribute.*'':: The value of the named host attribute. If an attribute of the specified does not exist, each comparison is treated as if the value does not match. + See the documentation for the *IS NULL* and *IS NOT NULL* operators for + ways to check if an attribute exists. '' may either be a string (when matching by object names) or match the type of the attribute's value (when matching attribute values). Attribute @@ -113,9 +126,9 @@ The following operators may be used, in addition, to match attribute values: Evaluates to true if the attribute value is less than, less than or equal to, greater than or equal to or greater than the specified value. -In addition, a named attribute may be check for existence using the *IS NULL* -and *IS NOT NULL* expressions. An attribute is considered to be *NULL* if it -is not set for a host. +In addition, a named attribute may be checked for existence using the *IS +NULL* and *IS NOT NULL* operators. An attribute is considered to be *NULL* if +it is not set for a host. FILTER clause ~~~~~~~~~~~~~ @@ -126,10 +139,11 @@ core properties of the stored objects. The basic syntax for filter clauses is the same as for matching clauses (see the description about subexpressions above). -The following common fields of stored objects may be queried: +The following fields (core properties) of stored objects may be queried: *:last_update*:: - The timestamp of the last update of the object. + The timestamp of the last update of the object. This value is based on + information provided by the queried backend if possible. *:age*:: The amount of time since the last update of the object. @@ -160,7 +174,7 @@ EXAMPLES The following examples illustrate the use of the commands and what their replies look like. The replies are pretty-printed to more easily follow them. - LIST; + LIST hosts; {"hosts":[{ "name": "host1.example.com", "last_update": "2001-02-03 04:05:06 +0700", @@ -171,7 +185,7 @@ replies look like. The replies are pretty-printed to more easily follow them. "update_interval": "5m4s" }]} - FETCH 'host1.example.com'; + FETCH host 'host1.example.com'; { "name": "host1.example.com", "last_update": "2001-02-03 04:05:06 +0700",