Update javascript-functions for setup documentation
diff --git a/source/documentation/query/javascript-functions.md b/source/documentation/query/javascript-functions.md
index cc0560a..89176bb 100644
--- a/source/documentation/query/javascript-functions.md
+++ b/source/documentation/query/javascript-functions.md
@@ -11,6 +11,10 @@
native JavaScript datatypes. RDFterms that do not fit easily into
JavaScript datatypes are handled with a object class `NV`.
+Applications should be aware that there are risks in exposing a script engine
+with full computational capabilities through SPARQL. Script functions are only
+as secure as the script engine environment they run in.
+
## Requirements
ARQ requires a javascript engine such as [GraalVM](https://www.graalvm.org/) to
@@ -35,21 +39,30 @@
<version>${ver.graalvm}</version>
</dependency>
```
-
-## Loading JavaScript functions
+
+## Enabling and Loading JavaScript functions
JavaScript is loaded from an external file using the context setting
"http://jena.apache.org/ARQ#js-library". This can be written as
`arq:js-library` for commands and Fuseki configuration files.
+Access to the script engine must be enabled at runtime.
+The Java system property to do this is `jena:scripting`.
+
Example:
+ export JVM_ARGS=-Djena:scripting=true
+ sparql --set arq:js-library=SomeFile.js --data ... --query ...
+
+and for MS Windows:
+
+ set JVM_ARGS=-Djena:scripting=true
sparql --set arq:js-library=SomeFile.js --data ... --query ...
will execute on the data with the JavaScript functions from file
"SomeFile.js" available.
-JavScript functions can also be set from a string directly from within Java using constant
+JavaScript functions can also be set from a string directly from within Java using constant
`ARQ.symJavaScriptFunctions` ("http://jena.apache.org/ARQ#js-functions").
## Using JavaScript functions
@@ -97,9 +110,10 @@
// Words to be combined are separated by a space in the string.
function toCamelCase(str) {
- return str.split(' ')
- .map(cc)
- .join('');
+ return str
+ .split(' ')
+ .map(cc)
+ .join('');
}
function ucFirst(word) {
@@ -123,11 +137,7 @@
VALUES ?input { "some woRDs to PROCESS" }
}
-which can be executed with:
-
- sparql --set arq:js-library=functions.js --query Q.rq
-
-and it results in:
+which results in:
--------------------------------------------------
| input | X |
@@ -140,6 +150,7 @@
The context setting can be provided on the command line starting the
server, for example:
+ export JVM_ARGS=-Djena:scripting=true
fuseki --set arq:js-library=functions.js --mem /ds
or it can be specified in the server configuration file `config.ttl`:
@@ -171,4 +182,5 @@
and used as:
+ export JVM_ARGS=-Djena:scripting=true
fuseki --conf config.ttl
