| commit | d9aa3794f882468351fcbeead550f5a2fb78aa19 | [log] [tgz] |
|---|---|---|
| author | Matthias Andreas Benkard <code@mail.matthias.benkard.de> | Tue Dec 05 21:22:22 2023 +0100 |
| committer | Matthias Andreas Benkard <code@mail.matthias.benkard.de> | Tue Dec 05 21:22:22 2023 +0100 |
| tree | 41733b04ddf371cd13b859694bc44bc715283657 | |
| parent | 1e5a5289f5ff6936c81b0e914a02746921de7c88 [diff] |
jgvariant-tool: Add example output to the readme file. Change-Id: Iec0b38e07b4c1529ac3b2b1aa810c58af3486ba6
This library provides a GVariant parser in pure Java.
jgvariant-core provides Decoder<T>, which read a given type of GVariant-encoded value from a ByteBuffer. The class also contains factory methods to acquire those instances.
The various subclasses of Decoder together implement the GVariant serialization specification.
jgvariant-ostree provides instances of Decoder<T> for various GVariant types used in OSTree repositories.
To parse a GVariant value of type "a(si)", which is an array of pairs of String and int, you can use the following code:
record ExampleRecord(String s, int i) {}
var decoder =
Decoder.ofArray(
Decoder.ofStructure(
ExampleRecord.class,
Decoder.ofString(StandardCharsets.UTF_8),
Decoder.ofInt().withByteOrder(ByteOrder.LITTLE_ENDIAN)));
byte[] bytes = ...;
List<ExampleRecord> example = decoder.decode(ByteBuffer.wrap(bytes));
The jgvariant-tool module contains a tool called jgvariant that can be used to manipulate GVariant-formatted files from the command line. Its primary purpose is to enable the scripting of OSTree repository management tasks.
Usage example (dumping the contents of an OSTree summary file):
$ jgvariant ostree summary read ./jgvariant-ostree/src/test/resources/ostree/summary
Output:
{
"entries": [
{
"ref": "mulkos/1.x/amd64",
"value": {
"checksum": "66ff167ff35ce87daac817447a9490a262ee75f095f017716a6eb1a9d9eb3350",
"metadata": {
"fields": {
"ostree.commit.timestamp": 1640537170
}
},
"size": 214
}
}
],
"metadata": {
"fields": {
"ostree.summary.last-modified": 1640537300,
"ostree.summary.tombstone-commits": false,
"ostree.static-deltas": {
"3d3b3329dca38871f29aeda1bf5854d76c707fa269759a899d0985c91815fe6f-66ff167ff35ce87daac817447a9490a262ee75f095f017716a6eb1a9d9eb3350": "03738040e28e7662e9c9d2599c530ea974e642c9f87e6c00cbaa39a0cdac8d44",
"31c8835d5c9d2c6687a50091c85142d1b2d853ff416a9fb81b4ee30754510d52": "f481144629474bd88c106e45ac405ebd75b324b0655af1aec14b31786ae1fd61",
"31c8835d5c9d2c6687a50091c85142d1b2d853ff416a9fb81b4ee30754510d52-3d3b3329dca38871f29aeda1bf5854d76c707fa269759a899d0985c91815fe6f": "2c6a07bc1cf4d7ce7d00f82d7d2d6d156fd0e31d476851b46dc2306b181b064a"
},
"ostree.summary.mode": "bare",
"ostree.summary.indexed-deltas": true
}
}
}
You can build the tool either as a shaded JAR or as a native executable.
To build and run a shaded JAR:
$ mvn package -pl jgvariant-tool -am -Pshade $ java -jar /home/mulk/Arbeitskasten/jgvariant/jgvariant-tool/target/jgvariant-tool-*.jar
To build and run a native executable:
$ mvn package -pl jgvariant-tool -am -Pnative $ ./jgvariant-tool/target/jgvariant
<project>
...
<dependencyManagement>
...
<dependencies>
<dependency>
<groupId>eu.mulk.jgvariant</groupId>
<artifactId>jgvariant-bom</artifactId>
<version>0.1.7</version>
<type>pom</type>
<scope>import</scope>
</dependency>
</dependencies>
...
</dependencyManagement>
<dependencies>
...
<dependency>
<groupId>eu.mulk.jgvariant</groupId>
<artifactId>jgvariant-core</artifactId>
</dependency>
<dependency>
<groupId>eu.mulk.jgvariant</groupId>
<artifactId>jgvariant-ostree</artifactId>
</dependency>
...
</dependencies>
...
</project>
dependencies {
...
implementation(platform("eu.mulk.jgvariant:jgvariant-bom:0.1.7")
implementation("eu.mulk.jgvariant:jgvariant-core")
implementation("eu.mulk.jgvariant:jgvariant-ostree")
...
}