GitHub - aiviet/loanpass-sdk-java: The SDK was designed to make LoanPASS APIs to be easily accessible with just a few lines of code.

Overview of the LoanPASS SDK for Java

The SDK was designed to make LoanPASS APIs to be easily accessible with just a few lines of code. Here are the highlighted features:

Provided both sync and async versions of the LoanPASS APIs
Convenient builder(s) to construct API requests safely through code-generated strong typed
Convenient annotation(s) and converters for safely:
- Serializing a (nested) POJO to an API request
- De-serializing an API response to a (nested) POJO
Utilities to:
- Generate enum KnownEnumId from get_configuration API
- Generate enum KnownFieldId from get_configuration API
- Generate GraphQL schema from enum KnownEnumId

If you would like to contribute to this project, please contact long@youland.com

Getting started

//Initialize LoanPass client
String api_key  = "Provide your LoanPass API Key"
Settings config = new Settings("https://api.loanpass.io/v1", api_key);
ILoanPassClient loanpassClient = new LoanPassClient(config);

//configuration
ConfigResponse configRes = loanpassClient.getConfiguration();

//execute-summary
ExecSummaryResponse sumRes = loanpassClient.postExecSummary(sumReq);

//execute-product
ExecProductResponse prodRes = loanpassClient.postExecProduct(prodReq);

How to build a request

There are two ways to build a request:

Strong typed version

FieldValueMapping.IBuilder fieldBuilder = new FieldValueMappingBuilder();
List<FieldValueMapping> fields = fieldBuilder
        .fieldEnum(KnownFieldId.LOAN_PURPOSE, "refinance")
        .fieldNumber(KnownFieldId.BASE_LOAN_AMOUNT, 2)
        .fieldString(KnownFieldId.STATE, "some text")
        .fieldDuration(KnownFieldId.DESIRED_LOAN_TERM, 3, DurationUnit.DAYS)
        .build();

ExecSummaryRequest.IBuilder builder = new ExecSummaryRequestBuilder();
builder.withTime(Instant.now())
        .withFields(fields);

ExecSummaryRequest request = builder.build();

Weak typed version

FieldValueMapping.IBuilder fieldBuilder = new FieldValueMappingBuilder();
List<FieldValueMapping> fields = fieldBuilder
        .fieldEnum("enumId", "a", "1")
        .fieldNumber("numId", 2)
        .fieldString("stId", "some text")
        .fieldDuration("durId", 3, DurationUnit.DAYS)
        .build();

ExecSummaryRequest.IBuilder builder = new ExecSummaryRequestBuilder();
builder.withTime(Instant.now())
        .withFields(fields);

ExecSummaryRequest request = builder.build();

Prerequisites of using strong typed builder

In order to build requests with strong typed, you need to generate the codes containing strong types of "creditApplicationFields" and "enumerations" from the result of get_configuration API. Here are the steps to generate the code:

Run the unit test of "LoanPassClientTest.test_getConfiguration" to retrieve the latest configuration.
Replace "test/testdata/config/response_sample.json" with the result above.
Run these 2 unit tests to generate the latest version of strong types above.
1. "EnumType2JavaGenTest"
2. "FieldDef2JavaGenTest"
Replace "KnownEnumId.java" and "KnownFieldId.java" with "temp/KnownEnumId.java.codegen" and "temp/KnownFieldId.java.codegen" generated from the previous step.

Creating a request with a few lines of code

Creating a request using strong typed bulder is good. Still, every field has to be hand drafted and most requests contain a dozen of fields. The better way to create a request in a few lines of code is to annotate your domain object model which is in turn converted into a request. Here is the unit test to demonstrate of use of Obj2FieldValueMapping.

private enum Loan_Purpose {
    PURCHASE,
    REFINANCE,
    MORTGAGE_MODIFICATION,
    ASSUMPTION
}

private class AnnotatedInputNested {
    @Tag(KnownFieldId.AFTER_REPAIR_VALUE_ARV)
    private Double afterRepairValue = 88.0;
}

private class AnnotatedInput {
    @Tag(KnownFieldId.LOAN_PURPOSE)
    private Loan_Purpose loanPurpose = Loan_Purpose.REFINANCE;

    @Tag(KnownFieldId.STATE)
    private String propertyState = "CA";

    @Tag(KnownFieldId.BASE_LOAN_AMOUNT)
    private Double loanAmount = 99.0;

    @TagDuration(value = KnownFieldId.DESIRED_LOAN_TERM, unit = DurationUnit.MONTHS)
    private Double loanTerm = 11.0;

    @TagObj
    private AnnotatedInputNested nestedInput = new AnnotatedInputNested();
}

//With a few annotations above, the AnnotatedInput source object can be converted to fields of a request 
AnnotatedInput source = new AnnotatedInput();
Obj2FieldValueMapping converter = new Obj2FieldValueMapping(source);
List<FieldValueMapping> result = converter.convert();

From API response to a POJO also in a few lines of code

License summary

Apache 2.0