JOOQ MockDataProvider - 如何根据某些条件返回不同的模拟？

Question

Recenty I was implementing a unit test using JOOQ MockDataProvider. When I wanted to use my mock provider in DAO with many selects I had to use many if-else statements.

According to: http://www.jooq.org/doc/latest/manual/tools/jdbc-mocking , I just need to check if my SQL starts with some query. And my SQLs used in DAO could start with 3 different ways, so I used pretty complex if-else construct.

Second thing - I wanted my MockDataProvider to return some mock result only when SQL is executed for the first time, and then not to return any results - in DAO iterated in loop 5 times, and each time my DAO should check something in database. I had no idea how to mock such behaviour, so I used simple counter - but it looks awful, and I want it to be implemented in a good way. Here is my code:

public class SomeProvider implements MockDataProvider {

private static final String STATEMENT_NOT_SUPPORTED_ = "Statement not supported: ";
private static final String SELECT_META = "select \"myschema\".\"meta\".";
private static final String SELECT_CLIENT = "select \"myschema\".\"client\".";
private static final String SELECT_KEY = "select \"myschema\".\"key\".";
private static final String TEST_SECRET_KEY = "some key";
private static final String KEY = "40sld";
private static final String DROP = "DROP";
private static final String SOME_URL = "something";
private static final String MONKEY = "monkey";
private static final int FIRST_ITERARION_COUNTER_VALUE = 0;
private final Long keyId;
int counter = 0;

public SomeProvider(Long keyId) {
    this.keyId = keyId;
}

@Override
public MockResult[] execute(MockExecuteContext ctx) throws SQLException {

    DSLContext create = DSL.using(SQLDialect.POSTGRES);
    MockResult[] mock = new MockResult[3];
    String sql = ctx.sql();
    if (sql.toUpperCase().startsWith(DROP)) {
        throw new SQLException(STATEMENT_NOT_SUPPORTED_ + sql);
    } else if (sql.startsWith(SELECT_CLIENT)) {

        Result<ClientRecord> result = create.newResult(CLIENT);
        result.add(create.newRecord(CLIENT));
        result.get(0).setValue(CLIENT.ID, 1L);
        result.get(0).setValue(CLIENT.SECRET_KEY, TEST_SECRET_KEY);
        mock[0] = new MockResult(1, result);

    } else if (sql.startsWith(SELECT_META)) {

        Result<MetaRecord> metaResult = create.newResult(META);
        metaResult.add(create.newRecord(META));
        metaResult.get(0).setValue(META.ID, 1L);

        metaResult.get(0).setValue(META.URL, SOME_URL);
        metaResult.get(0).setValue(META.KEY, KEY);
        metaResult.get(0).setValue(META.OPTION, keyId);
        mock[0] = new MockResult(1, metaResult);

    } else if (sql.startsWith(SELECT_KEY)) {

        Result<KeyRecord> keyResult = create.newResult(KEY);
        if (counter == FIRST_ITERARION_COUNTER_VALUE) {
            // first SELECT returns monkey, rest will return no results
            keyResult.add(create.newRecord(KEY));
            keyResult.get(0).setValue(KEY.ID, 1L);
            keyResult.get(0).setValue(KEY.VALUE, MONKEY);
            mock[0] = new MockResult(1, keyResult);
        } else {
            mock[0] = new MockResult(0, keyResult);
        }
        counter++;
    }

    return mock;
}
}

It works but looks bad. To sum up my question is: How to return (using one provider) different results depending on the query and the number of query executions. Maybe this class is only for simple DSLContext mocking, not to mock whole DAO which uses many queries many times using one DSLContext.

Answer 1

I have done this and it is no fun - the mock in the end needs tests of its own... Another approach, is to enable the mock provider to be configurable with what to expect and what to return.

provider.when(..).times(5).return(...)

And so on... The return can take a generator as well as literal values. The when could use regex as well as strings