https://github.com/berrycloud/xapi-java
Java xAPI model, client and tools
https://github.com/berrycloud/xapi-java
cmi5 java spring tincan xapi
Last synced: 3 months ago
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Java xAPI model, client and tools
- Host: GitHub
- URL: https://github.com/berrycloud/xapi-java
- Owner: BerryCloud
- License: apache-2.0
- Created: 2022-12-12T16:59:43.000Z (over 2 years ago)
- Default Branch: main
- Last Pushed: 2024-10-31T12:17:41.000Z (7 months ago)
- Last Synced: 2024-10-31T13:25:16.768Z (7 months ago)
- Topics: cmi5, java, spring, tincan, xapi
- Language: Java
- Homepage: https://berrycloud.co.uk
- Size: 1.01 MB
- Stars: 15
- Watchers: 4
- Forks: 4
- Open Issues: 1
-
Metadata Files:
- Readme: README.md
- License: LICENSE
- Code of conduct: CODE_OF_CONDUCT.md
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README
# xAPI Java [](https://github.com/BerryCloud/xapi-java/actions/workflows/codeql.yml) [](https://sonarcloud.io/summary/new_code?id=BerryCloud_xapi-java)
xAPI Java helps you to create applications that send or receive xAPI [Statements](https://github.com/adlnet/xAPI-Spec/blob/master/xAPI-Data.md#statements) or [Documents](https://github.com/adlnet/xAPI-Spec/blob/master/xAPI-Data.md#10-documents).
There are two projects in this [Monorepo](https://en.wikipedia.org/wiki/Monorepo), xAPI Client and xAPI Model.
Both the xAPI Client and xAPI Model use a [fluent interface](https://en.wikipedia.org/wiki/Fluent_interface). Objects are [immutable](https://en.wikipedia.org/wiki/Immutable_object).
[CheckStyle](https://checkstyle.sourceforge.io) is used to enforce the [Google Java Style Guide](https://google.github.io/styleguide/javaguide.html). Sonar performs automatic pull request reviews. [CodeQL](https://codeql.github.com) scans for vulnerabilities. The number of bugs, code smells and vulnerabilities in the codebase can be viewed in SonarCloud. The code coverage and code duplication percentages can also be viewed in SonarCloud. Over three-hundred unit tests ensure conformance with the xAPI specification.
## Requirements
xAPI Java requires Java 17 or newer.
## xAPI Java Client
The xAPI Java Client can be used by learning record providers (LRP) to communicate with learning record stores (LRS) or a system which follows the LRS requirements of one or more of the xAPI resources.
### Getting started
To use the xAPI Java Client include the appropriate XML in the `dependencies` section of your `pom.xml`, as shown in the following example:
```xml
4.0.0
getting-started
dev.learning.xapi
xapi-client
1.1.11
```
xAPI Java Client is available in the [Maven Central Repository](https://central.sonatype.com/artifact/dev.learning.xapi/xapi-client/).
### Configuration
The xAPI Java Client has a Spring AutoConfiguration bean which picks up the following properties:
| Property | Description |
| ------------------------- | ------------------------------------------------------------------------------- |
| xapi.client.baseUrl | The base url of the LRS endpoint |
| xapi.client.username | Username for basic authorization header |
| xapi.client.password | Password for basic authorization header |
| xapi.client.authorization | Authorization header (has precedence over the username and password properties) |
Properties can be set using any [external configuration](https://docs.spring.io/spring-boot/docs/3.0.6/reference/htmlsingle/#features.external-config.files) method supported by Spring Boot.
If you need more specific customization (eg. your LRS needs specific headers, or you want to set the authorization header dynamically) you can create a custom configurer by implementing the `XapiClientConfigurer` interface.
### Advanced Configuration
The xAPI Java Client uses the Spring WebClient. Spring WebClient has default memory limit of 256KB for buffering data. If this limit is exceeded then a DataBufferLimitException will be thrown.
The default memory limit of 256KB for buffering data could be exceeded if the LRS returns a large number of Statements or if the Statements contain attachments.
It is possible to set the memory limit for buffering data with the `spring.codec.max-in-memory-size` property.
Example:
```
spring.codec.max-in-memory-size=1MB
```
### Statement Resource
The xAPI Java Client allows applications to store and fetch xAPI [Statements](https://github.com/adlnet/xAPI-Spec/blob/master/xAPI-Data.md#statements).
### Getting a Statement
Example:
```java
var response = client.getStatement(r -> r.id("4df42866-40e7-45b6-bf7c-8d5fccbdccd6")).block();
Statement statement = response.getBody();
```
### Getting a Statement with attachments
Example:
```java
var response = client.getStatement(r -> r.id("4df42866-40e7-45b6-bf7c-8d5fccbdccd6").attachments(true).block();
Statement statement = response.getBody();
```
### Getting Statements
Example:
```java
var response = client.getStatements().block();
StatementResult statementResult = response.getBody();
Statement[] statements = statementResult.getStatements();
```
### Getting the next page of Statements
Example:
```java
var response = client.getStatements().block();
var moreResponse = client.getMoreStatements(r -> r.more(response.getBody().getMore())).block();
StatementResult moreStatementResult = moreResponse.getBody();
Statement[] statements = moreStatementResult.getStatements();
```
### Getting Statements as Iterator (and processing them as a Stream)
In most cases it is preferable to use `getStatementIterator()` instead of `getStatments()` and `getMoreStatements()`.
Example:
```java
var statements = client.getStatementIterator().block();
// process the first 100 Statements
statements.toStream().limit(100).forEach(s -> {
// add logic here...
});
```
### Posting a Statement
Example:
```java
client.postStatement(
r -> r.statement(s -> s.agentActor(a -> a.name("A N Other").mbox("mailto:[email protected]"))
.verb(Verb.ATTEMPTED)
.activityObject(o -> o.id("https://example.com/activity/simplestatement")
.definition(d -> d.addName(Locale.ENGLISH, "Simple Statement")))))
.block();
```
### Posting a Statement with an attachment
Example:
```java
client.postStatement(
r -> r.statement(s -> s.agentActor(a -> a.name("A N Other").mbox("mailto:[email protected]"))
.verb(Verb.ATTEMPTED)
.activityObject(o -> o.id("https://example.com/activity/simplestatement")
.definition(d -> d.addName(Locale.ENGLISH, "Simple Statement")))
.addAttachment(a -> a.content("Simple attachment").length(17).contentType("text/plain")
.usageType(URI.create("https://example.com/attachments/simplestatement"))
.addDisplay(Locale.ENGLISH, "text attachment"))
)).block();
```
### Posting a Signed Statement
Example:
```java
client.postStatement(
r -> r.signedStatement(s -> s.agentActor(a -> a.name("A N Other").mbox("mailto:[email protected]"))
.verb(Verb.ATTEMPTED)
.activityObject(o -> o.id("https://example.com/activity/simplestatement")
.definition(d -> d.addName(Locale.ENGLISH, "Simple Statement"))),
keyPair.getPrivate()))
.block();
```
### Posting Statements
Example:
```java
Statement attemptedStatement = Statement.builder()
.agentActor(a -> a.name("A N Other").mbox("mailto:[email protected]")).verb(Verb.ATTEMPTED)
.activityObject(o -> o.id("https://example.com/activity/simplestatement")
.definition(d -> d.addName(Locale.ENGLISH, "Simple Statement")))
.build();
Statement passedStatement = attemptedStatement.toBuilder().verb(Verb.PASSED).build();
client.postStatements(r -> r.statements(attemptedStatement, passedStatement)).block();
```
### Getting a voided Statement
Example:
```java
var response = client.getVoidedStatement(r -> r.id("4df42866-40e7-45b6-bf7c-8d5fccbdccd6")).block();
Statement voidedStatement = response.getBody();
```
### State Resource
The xAPI Java Client allows applications to store, change, fetch, or delete [state documents](https://github.com/adlnet/xAPI-Spec/blob/master/xAPI-Communication.md#23-state-resource).
#### Getting a state
Example:
```java
var response = client.getState(r -> r.activityId("https://example.com/activity/1")
.agent(a -> a.name("A N Other").mbox("mailto:[email protected]"))
.registration("67828e3a-d116-4e18-8af3-2d2c59e27be6")
.stateId("bookmark"), String.class)
.block();
String state = response.getBody();
```
#### Posting a state
Example:
```java
client.postState(r -> r.activityId("https://example.com/activity/1")
.agent(a -> a.name("A N Other").mbox("mailto:[email protected]"))
.registration("67828e3a-d116-4e18-8af3-2d2c59e27be6")
.stateId("bookmark")
.state("Hello World!"))
.block();
```
#### Putting a state
Example:
```java
client.putState(r -> r.activityId("https://example.com/activity/1")
.agent(a -> a.name("A N Other").mbox("mailto:[email protected]"))
.registration("67828e3a-d116-4e18-8af3-2d2c59e27be6")
.stateId("bookmark")
.state("Hello World!"))
.block();
```
#### Deleting a state
Example:
```java
client.deleteState(r -> r.activityId("https://example.com/activity/1")
.agent(a -> a.name("A N Other").mbox("mailto:[email protected]"))
.registration("67828e3a-d116-4e18-8af3-2d2c59e27be6")
.stateId("bookmark"))
.block();
```
### Samples
The samples folder in this repository contains [sample applications](samples) that use the xAPI client.
## xAPI Model Spring Boot Starter
The xAPI specification has strict rules for API requests/responses formatting. The xAPI Model has inbuilt validation for all of these rules. However, if you plan to use the xAPI Model, you should keep in mind that some activity providers do not fully conform to these rules.
In some cases it may be desirable to turn off some or all of the rules in order to be compatible with a wider range of xAPI activity providers. However, it should be noted that doing this is in violation of the xAPI specification.
The xAPI Model Spring Boot Starter package provides an easy way to turn on/off these validation rules.
### Getting started
To use the xAPI Model Spring Boot Starter include the appropriate XML in the `dependencies` section of your `pom.xml`, as shown in the following example:
```xml
dev.learning.xapi
xapi-model-spring-boot-starter
1.1.11
```
xAPI Model Spring Boot Starter is available in the [Maven Central Repository](https://central.sonatype.com/artifact/dev.learning.xapi/xapi-model-spring-boot-starter/).
### Configuration
The xAPI Model Spring Boot Starter has a Spring AutoConfiguration bean which picks up the following properties:
| Property | Description |
| ---------------------------------------- | -------------------------------------------------------------------------- |
| xapi.model.validateJson | Fail on trailing JSON tokens |
| xapi.model.validateProperties | Fail on unknown JSON properties |
| xapi.model.validateNullValues | Fail on null JSON properties |
| xapi.model.validateLiterals | Fail on number and boolean JSON properties defined as string |
| xapi.model.validateObjectType | Fail on invalid JSON objectType property |
| xapi.model.validateLocale | Fail on invalid Locale strings |
| xapi.model.validateTimestamp | Fail on negative zero timezone offsets |
| xapi.model.validateActivityDefinition | Fail on invalid xAPI ActivityDefinition (missing properties) |
| xapi.model.validateActor | Fail on invalid xAPI Actor (missing or multiple identifiers) |
| xapi.model.validateAuthority | Fail on invalid xAPI Authority object |
| xapi.model.validateUriScheme | Fail on invalid xAPI URI property (missing scheme) |
| xapi.model.validateMbox | Fail on invalid xAPI mbox property (invalid email or missing prefix) |
| xapi.model.validateLocaleNotUndetermined | Fail on invalid xAPI locale property (locale is undetermined) |
| xapi.model.validateScaledScore | Fail on invalid xAPI scaledScore property (out of -1 - 1 range) |
| xapi.model.validateScore | Fail on invalid xAPI Score (raw score is out of min/max range) |
| xapi.model.validateStatementPlatform | Fail on invalid xAPI context.platform (if present object must be Activity) |
| xapi.model.validateStatementRevision | Fail on invalid xAPI context.revision (if present object must be Activity) |
| xapi.model.validateStatementListIds | Fail on invalid xAPI statement List (conflicting statement ids) |
| xapi.model.validateStatementVerb | Fail on invalid xAPI voided statement (object must be StatemnetReference) |
| xapi.model.validateUuidVariant | Fail on invalid xAPI UUID property (must be UUID variant 4) |
The default value is **TRUE** for all of the above properties.
## xAPI Java Model
The xAPI model can be used by clients that send xAPI data or by servers that receive xAPI data.
### Getting started
To use the xAPI Model include the appropriate XML in the `dependencies` section of your `pom.xml`, as shown in the following example:
```xml
4.0.0
getting-started
dev.learning.xapi
xapi-model
1.1.11
```
xAPI Model is available in the [Maven Central Repository](https://central.sonatype.com/artifact/dev.learning.xapi/xapi-model/).
### Creating a statement
Example:
```java
Statement statement = Statement.builder()
.agentActor(a -> a.name("A N Other").mbox("mailto:[email protected]"))
.verb(Verb.ATTEMPTED)
.activityObject(o -> o.id("https://example.com/activity/simplestatement")
.definition(d -> d.addName(Locale.ENGLISH, "Simple Statement")))
.build();
```
### Deserializing Statements
The Jackson ObjectMapper can be used to deserialize statements into Java objects.
Example:
```java
String json = """
{
"actor":{
"objectType":"Agent",
"name":"A N Other",
"mbox":"mailto:[email protected]"
},
"verb":{
"id":"http://adlnet.gov/expapi/verbs/attempted",
"display":{
"und":"attempted"
}
},
"object":{
"objectType":"Activity",
"id":"https://example.com/activity/simplestatement",
"definition":{
"name":{
"en":"Simple Statement"
}
}
}
}""";
Statement statement = objectMapper.readValue(json, Statement.class);
```
### Serializing Statements
The Jackson ObjectMapper can be used to serialize Statement objects into JSON.
Example:
```java
Statement statement = Statement.builder()
.agentActor(a -> a.name("A N Other").mbox("mailto:[email protected]")).verb(Verb.ATTEMPTED)
.activityObject(o -> o.id("https://example.com/activity/simplestatement")
.definition(d -> d.addName(Locale.ENGLISH, "Simple Statement")))
.build();
String json = objectMapper.writeValueAsString(statement);
```
### Creating a new statement using an existing statement as template
Example:
```java
Statement passed = Statement.builder()
.agentActor(a -> a.name("A N Other").mbox("mailto:[email protected]")).verb(Verb.PASSED)
.activityObject(o -> o.id("https://example.com/activity/simplestatement")
.definition(d -> d.addName(Locale.ENGLISH, "Simple Statement")))
.build();
Statement completed = passed.toBuilder().verb(Verb.COMPLETED).build();
```
### Validating Statements
Statements can be validated programmatically.
Example:
```java
Validator validator = Validation.buildDefaultValidatorFactory().getValidator();
Statement statement = Statement.builder()
.agentActor(a -> a.name("A N Other").mbox("mailto:[email protected]"))
.activityObject(o -> o.id("https://example.com/xapi/activity/simplestatement"))
.build();
Set> constraintViolations = validator.validate(statement);
System.out.println(constraintViolations)
// Prints [ConstraintViolationImpl{interpolatedMessage='must not be null', propertyPath=verb, rootBeanClass=class dev.learning.xapi.model.Statement, messageTemplate='{jakarta.validation.constraints.NotNull.message}'}]
```
Statements can also be validated when they are received by a method in a REST controller. The following example requires Spring MVC and the Hibernate Validator.
```java
@PostMapping
public ResponseEntity> postStatements(
@RequestBody List<@Valid Statement> statements) {
// Process the statements
return new ResponseEntity<>(HttpStatus.OK);
}
```