Configuration

Qlue-ls can be configured through a qlue-ls.toml or qlue-ls.yml file.

Here is an example configuration:

[format]
align_prefixes = false
align_predicates = true
separate_prologue = false
capitalize_keywords = true
insert_spaces = true
tab_size = 2
where_new_line = false
filter_same_line = true
line_length = 120
contract_triples = false

[completion]
timeout_ms = 5000
result_size_limit = 100
subject_completion_trigger_length = 3
object_completion_suffix = true
variable_completion_limit = 10
same_subject_semicolon = true

auto_line_break = false

[prefixes]
add_missing = true
remove_unused = false

Format settings

format.align_prefixes

Type	Default
boolean	false

Indent all prefixes s.t. they align:

PREFIX wikibase: <http://wikiba.se/ontology#>
PREFIX rdf:      <http://www.w3.org/1999/02/22-rdf-syntax-ns#>

format.align_predicates

Type	Default
boolean	true

Indent predicates in a property list s.t. they align:

?subject rdf:type ?type .
         rdfs:label label

This setting also controls on-type formatting: when pressing Enter after ;, the new line is indented to the predicate column when true, or to depth + one tab when false. See On-type Formatting.

format.separate_prologue

Type	Default
boolean	false

Separate Prologue from query with a line break:

PREFIX rdf:      <http://www.w3.org/1999/02/22-rdf-syntax-ns#>

format.capitalize_keywords

Type	Default
boolean	true

Capitalize all keywords.

format.insert_spaces

Type	Default
boolean	true

Use spaces and not tabs.

format.tab_size

Type	Default
integer	2

How wide a tab is.

format.where_new_line

Type	Default
boolean	false

Insert newline before each WHERE:

SELECT *
WHERE {}

format.filter_same_line

Type	Default
boolean	true

Allow trailing filter statements:

SELECT * WHERE {
    ?a ?b ?c Filter(?a)
}

format.line_length

Type	Default
integer	120

Maximum line length before SELECT clauses break across multiple lines. When a SELECT clause exceeds this length, each binding is placed on a new line with proper indentation:

SELECT ?variable1
       ?variable2
       ?variable3
WHERE {}

format.contract_triples

Type	Default
boolean	false

When enabled, automatically contracts consecutive triples with the same subject using semicolon notation.

# Before (contract_triples = false)
SELECT * WHERE {
  ?person <name> ?name .
  ?person <age> ?age .
}

# After (contract_triples = true)
SELECT * WHERE {
  ?person <name> ?name ;
          <age> ?age .
}

When align_predicates = true (default), the contracted predicates are aligned with the first predicate. When align_predicates = false, a fixed 2-space indentation is used.

format.keep_empty_lines

Type	Default
boolean	false

When enabled, preserves intentional blank lines from the original source. Consecutive blank lines are collapsed into a single empty line.

Completion settings

completion.timeout_ms

Type	Default
integer	5000

Time (in ms) a completion query is allowed to take.

completion.result_size_limit

Type	Default
integer	100

The result size of a completion query.

completion.subject_completion_trigger_length

Type	Default
integer	3

The amount of chars (actually bytes) required to trigger a subject completion. This concerns online completions and not variable or construct completions!

completion.object_completion_suffix

Type	Default
boolean	true

Automatically append .\n after object completions. This helps with writing triple patterns by automatically closing the statement.

completion.variable_completion_limit

Type	Default
integer	none

Maximum number of variable completions to suggest. When not set (default), all variables in the query are suggested. Set this to limit suggestions when queries have many variables.

completion.same_subject_semicolon

Type	Default
boolean	true

When completing a subject that matches the previous triple's subject, transform the completion to use semicolon notation instead of starting a new triple. This allows you to continue adding predicates to the same subject without repeating it.

For example, if you have:

?person rdf:type foaf:Person .

And you complete ?person as the next subject, it will transform to:

?person rdf:type foaf:Person ;
        |

Where | represents your cursor position, ready to add another predicate.

On-type formatting settings

auto_line_break

Type	Default
boolean	false

When enabled, typing ; or . after a valid triple automatically inserts a newline with correct indentation.

• After ;: new line indented to predicate column (or base + tab when align_predicates = false)
• After .: new line at base brace-depth indent

This only applies when the preceding triple is syntactically complete (has subject, predicate, and object). Incomplete triples are ignored.

See On-type Formatting for more details.

Prefix settings

prefixes.add_missing

Type	Default
boolean	true

Define missing prefix declarations as soon as they are needed.

prefixes.remove_unused

Type	Default
boolean	false

Remove prefix declarations if they are not used.

Warning

Turn off if you plan to define custom prefixes!!

Backend settings

Backends represent knowledge bases that the LSP can connect to in order to provide smart completions.

backend.name

Type	Required	Default
string	yes	—

The name of the backend.

backend.url

Type	Required	Default
string	yes	—

The URL for the SPARQL service to query for completions.

backend.healthCheckUrl

Type	Required	Default
string	no	—

A URL to probe to test availability of the backend for completions.

backend.engine

Type	Required	Default
string	no	—

The SPARQL engine type. One of QLever, GraphDB, Virtuoso, MillenniumDB, Blazegraph, Jena.

backend.requestMethod

Type	Required	Default
string	no	GET

The HTTP method to use for requests to this backend service.

backend.prefixMap

Type	Required	Default
map	no	{}

A mapping of RDF prefixes to IRIs that will be predefined for use with this backend.

backend.default

Type	Required	Default
boolean	no	false

Whether to activate this backend by default at server start. Inactive backends can be activated via an LSP request to qlueLs/updateDefaultBackend.

backend.queries

Type	Required	Default
map	no	{}

The SPARQL queries used for completions by the LSP. See the Completion Queries guide for details.

backend.additionalData

Type	Required	Default
any	no	—

Arbitrary additional data to attach to the backend configuration.