Examples with SamzaSqlExecutionContext org.apache.samza.sql.data.SamzaSqlExecutionContext used on opensource projects

Example 1 with SamzaSqlExecutionContext

use of org.apache.samza.sql.data.SamzaSqlExecutionContext in project samza by apache.

the class QueryTranslator method translate.

/**
 * For unit testing only
 */
@VisibleForTesting
void translate(SamzaSqlQueryParser.QueryInfo queryInfo, StreamApplicationDescriptor appDesc, int queryId) {
    QueryPlanner planner = new QueryPlanner(sqlConfig.getRelSchemaProviders(), sqlConfig.getInputSystemStreamConfigBySource(), sqlConfig.getUdfMetadata(), sqlConfig.isQueryPlanOptimizerEnabled());
    final RelRoot relRoot = planner.plan(queryInfo.getSelectQuery());
    SamzaSqlExecutionContext executionContext = new SamzaSqlExecutionContext(sqlConfig);
    TranslatorContext translatorContext = new TranslatorContext(appDesc, relRoot, executionContext);
    translate(relRoot, sqlConfig.getOutputSystemStreams().get(queryId), translatorContext, queryId);
    Map<Integer, TranslatorContext> translatorContexts = new HashMap<>();
    translatorContexts.put(queryId, translatorContext.clone());
    appDesc.withApplicationTaskContextFactory(new ApplicationTaskContextFactory<SamzaSqlApplicationContext>() {

        @Override
        public SamzaSqlApplicationContext create(ExternalContext externalContext, JobContext jobContext, ContainerContext containerContext, TaskContext taskContext, ApplicationContainerContext applicationContainerContext) {
            return new SamzaSqlApplicationContext(translatorContexts);
        }
    });
}

Example 2 with SamzaSqlExecutionContext

use of org.apache.samza.sql.data.SamzaSqlExecutionContext in project samza by apache.

the class TestFilterTranslator method testTranslate.

@Test
public void testTranslate() throws IOException, ClassNotFoundException {
    // setup mock values to the constructor of FilterTranslator
    LogicalFilter mockFilter = PowerMockito.mock(LogicalFilter.class);
    Context mockContext = mock(Context.class);
    ContainerContext mockContainerContext = mock(ContainerContext.class);
    TranslatorContext mockTranslatorContext = mock(TranslatorContext.class);
    TestMetricsRegistryImpl metricsRegistry = new TestMetricsRegistryImpl();
    RelNode mockInput = mock(RelNode.class);
    when(mockFilter.getInput()).thenReturn(mockInput);
    when(mockInput.getId()).thenReturn(1);
    when(mockFilter.getId()).thenReturn(2);
    StreamApplicationDescriptorImpl mockGraph = mock(StreamApplicationDescriptorImpl.class);
    OperatorSpec<Object, SamzaSqlRelMessage> mockInputOp = mock(OperatorSpec.class);
    MessageStream<SamzaSqlRelMessage> mockStream = new MessageStreamImpl<>(mockGraph, mockInputOp);
    when(mockTranslatorContext.getMessageStream(eq(1))).thenReturn(mockStream);
    doAnswer(this.getRegisterMessageStreamAnswer()).when(mockTranslatorContext).registerMessageStream(eq(2), any(MessageStream.class));
    RexToJavaCompiler mockCompiler = mock(RexToJavaCompiler.class);
    when(mockTranslatorContext.getExpressionCompiler()).thenReturn(mockCompiler);
    Expression mockExpr = mock(Expression.class);
    when(mockCompiler.compile(any(), any())).thenReturn(mockExpr);
    when(mockContext.getContainerContext()).thenReturn(mockContainerContext);
    when(mockContainerContext.getContainerMetricsRegistry()).thenReturn(metricsRegistry);
    // Apply translate() method to verify that we are getting the correct filter operator constructed
    FilterTranslator filterTranslator = new FilterTranslator(1);
    filterTranslator.translate(mockFilter, LOGICAL_OP_ID, mockTranslatorContext);
    // make sure that context has been registered with LogicFilter and output message streams
    verify(mockTranslatorContext, times(1)).registerRelNode(2, mockFilter);
    verify(mockTranslatorContext, times(1)).registerMessageStream(2, this.getRegisteredMessageStream(2));
    when(mockTranslatorContext.getRelNode(2)).thenReturn(mockFilter);
    when(mockTranslatorContext.getMessageStream(2)).thenReturn(this.getRegisteredMessageStream(2));
    StreamOperatorSpec filterSpec = (StreamOperatorSpec) Whitebox.getInternalState(this.getRegisteredMessageStream(2), "operatorSpec");
    assertNotNull(filterSpec);
    assertEquals(filterSpec.getOpCode(), OperatorSpec.OpCode.FILTER);
    // Verify that the describe() method will establish the context for the filter function
    Map<Integer, TranslatorContext> mockContexts = new HashMap<>();
    mockContexts.put(1, mockTranslatorContext);
    when(mockContext.getApplicationTaskContext()).thenReturn(new SamzaSqlApplicationContext(mockContexts));
    filterSpec.getTransformFn().init(mockContext);
    FilterFunction filterFn = (FilterFunction) Whitebox.getInternalState(filterSpec, "filterFn");
    assertNotNull(filterFn);
    assertEquals(mockTranslatorContext, Whitebox.getInternalState(filterFn, "translatorContext"));
    assertEquals(mockFilter, Whitebox.getInternalState(filterFn, "filter"));
    assertEquals(mockExpr, Whitebox.getInternalState(filterFn, "expr"));
    // Verify MetricsRegistry works with Project
    assertEquals(1, metricsRegistry.getGauges().size());
    assertTrue(metricsRegistry.getGauges().get(LOGICAL_OP_ID).size() > 0);
    assertEquals(1, metricsRegistry.getCounters().size());
    assertEquals(3, metricsRegistry.getCounters().get(LOGICAL_OP_ID).size());
    assertEquals(0, metricsRegistry.getCounters().get(LOGICAL_OP_ID).get(0).getCount());
    assertEquals(0, metricsRegistry.getCounters().get(LOGICAL_OP_ID).get(1).getCount());
    // Calling filterFn.apply() to verify the filter function is correctly applied to the input message
    SamzaSqlRelMessage mockInputMsg = new SamzaSqlRelMessage(new ArrayList<>(), new ArrayList<>(), new SamzaSqlRelMsgMetadata(0L, 0L));
    SamzaSqlExecutionContext executionContext = mock(SamzaSqlExecutionContext.class);
    DataContext dataContext = mock(DataContext.class);
    when(mockTranslatorContext.getExecutionContext()).thenReturn(executionContext);
    when(mockTranslatorContext.getDataContext()).thenReturn(dataContext);
    Object[] result = new Object[1];
    doAnswer(invocation -> {
        Object[] retValue = invocation.getArgumentAt(4, Object[].class);
        retValue[0] = new Boolean(true);
        return null;
    }).when(mockExpr).execute(eq(executionContext), eq(mockContext), eq(dataContext), eq(mockInputMsg.getSamzaSqlRelRecord().getFieldValues().toArray()), eq(result));
    assertTrue(filterFn.apply(mockInputMsg));
    doAnswer(invocation -> {
        Object[] retValue = invocation.getArgumentAt(4, Object[].class);
        retValue[0] = new Boolean(false);
        return null;
    }).when(mockExpr).execute(eq(executionContext), eq(mockContext), eq(dataContext), eq(mockInputMsg.getSamzaSqlRelRecord().getFieldValues().toArray()), eq(result));
    assertFalse(filterFn.apply(mockInputMsg));
    // Verify filterFn.apply() updates the MetricsRegistry metrics
    assertEquals(2, metricsRegistry.getCounters().get(LOGICAL_OP_ID).get(0).getCount());
    assertEquals(1, metricsRegistry.getCounters().get(LOGICAL_OP_ID).get(1).getCount());
}

Example 3 with SamzaSqlExecutionContext

use of org.apache.samza.sql.data.SamzaSqlExecutionContext in project samza by apache.

the class TestJoinTranslator method testTranslateStreamToTableJoin.

private void testTranslateStreamToTableJoin(boolean isRemoteTable) throws IOException, ClassNotFoundException {
    // setup mock values to the constructor of JoinTranslator
    final String logicalOpId = "sql0_join3";
    final int queryId = 0;
    LogicalJoin mockJoin = PowerMockito.mock(LogicalJoin.class);
    TranslatorContext mockTranslatorContext = mock(TranslatorContext.class);
    RelNode mockLeftInput = PowerMockito.mock(LogicalTableScan.class);
    RelNode mockRightInput = mock(RelNode.class);
    List<RelNode> inputs = new ArrayList<>();
    inputs.add(mockLeftInput);
    inputs.add(mockRightInput);
    RelOptTable mockLeftTable = mock(RelOptTable.class);
    when(mockLeftInput.getTable()).thenReturn(mockLeftTable);
    List<String> qualifiedTableName = Arrays.asList("test", "LeftTable");
    when(mockLeftTable.getQualifiedName()).thenReturn(qualifiedTableName);
    when(mockLeftInput.getId()).thenReturn(1);
    when(mockRightInput.getId()).thenReturn(2);
    when(mockJoin.getId()).thenReturn(3);
    when(mockJoin.getInputs()).thenReturn(inputs);
    when(mockJoin.getLeft()).thenReturn(mockLeftInput);
    when(mockJoin.getRight()).thenReturn(mockRightInput);
    RexCall mockJoinCondition = mock(RexCall.class);
    when(mockJoinCondition.isAlwaysTrue()).thenReturn(false);
    when(mockJoinCondition.getKind()).thenReturn(SqlKind.EQUALS);
    when(mockJoin.getCondition()).thenReturn(mockJoinCondition);
    RexInputRef mockLeftConditionInput = mock(RexInputRef.class);
    RexInputRef mockRightConditionInput = mock(RexInputRef.class);
    when(mockLeftConditionInput.getIndex()).thenReturn(0);
    when(mockRightConditionInput.getIndex()).thenReturn(0);
    List<RexNode> condOperands = new ArrayList<>();
    condOperands.add(mockLeftConditionInput);
    condOperands.add(mockRightConditionInput);
    when(mockJoinCondition.getOperands()).thenReturn(condOperands);
    RelDataType mockLeftCondDataType = mock(RelDataType.class);
    RelDataType mockRightCondDataType = mock(RelDataType.class);
    when(mockLeftCondDataType.getSqlTypeName()).thenReturn(SqlTypeName.BOOLEAN);
    when(mockRightCondDataType.getSqlTypeName()).thenReturn(SqlTypeName.BOOLEAN);
    when(mockLeftConditionInput.getType()).thenReturn(mockLeftCondDataType);
    when(mockRightConditionInput.getType()).thenReturn(mockRightCondDataType);
    RelDataType mockLeftRowType = mock(RelDataType.class);
    // ?? why ??
    when(mockLeftRowType.getFieldCount()).thenReturn(0);
    when(mockLeftInput.getRowType()).thenReturn(mockLeftRowType);
    List<String> leftFieldNames = Collections.singletonList("test_table_field1");
    List<String> rightStreamFieldNames = Collections.singletonList("test_stream_field1");
    when(mockLeftRowType.getFieldNames()).thenReturn(leftFieldNames);
    RelDataType mockRightRowType = mock(RelDataType.class);
    when(mockRightInput.getRowType()).thenReturn(mockRightRowType);
    when(mockRightRowType.getFieldNames()).thenReturn(rightStreamFieldNames);
    StreamApplicationDescriptorImpl mockAppDesc = mock(StreamApplicationDescriptorImpl.class);
    OperatorSpec<Object, SamzaSqlRelMessage> mockLeftInputOp = mock(OperatorSpec.class);
    MessageStream<SamzaSqlRelMessage> mockLeftInputStream = new MessageStreamImpl<>(mockAppDesc, mockLeftInputOp);
    when(mockTranslatorContext.getMessageStream(eq(mockLeftInput.getId()))).thenReturn(mockLeftInputStream);
    OperatorSpec<Object, SamzaSqlRelMessage> mockRightInputOp = mock(OperatorSpec.class);
    MessageStream<SamzaSqlRelMessage> mockRightInputStream = new MessageStreamImpl<>(mockAppDesc, mockRightInputOp);
    when(mockTranslatorContext.getMessageStream(eq(mockRightInput.getId()))).thenReturn(mockRightInputStream);
    when(mockTranslatorContext.getStreamAppDescriptor()).thenReturn(mockAppDesc);
    InputOperatorSpec mockInputOp = mock(InputOperatorSpec.class);
    OutputStreamImpl mockOutputStream = mock(OutputStreamImpl.class);
    when(mockInputOp.isKeyed()).thenReturn(true);
    when(mockOutputStream.isKeyed()).thenReturn(true);
    doAnswer(this.getRegisterMessageStreamAnswer()).when(mockTranslatorContext).registerMessageStream(eq(3), any(MessageStream.class));
    RexToJavaCompiler mockCompiler = mock(RexToJavaCompiler.class);
    when(mockTranslatorContext.getExpressionCompiler()).thenReturn(mockCompiler);
    Expression mockExpr = mock(Expression.class);
    when(mockCompiler.compile(any(), any())).thenReturn(mockExpr);
    if (isRemoteTable) {
        doAnswer(this.getRegisteredTableAnswer()).when(mockAppDesc).getTable(any(RemoteTableDescriptor.class));
    } else {
        IntermediateMessageStreamImpl mockPartitionedStream = new IntermediateMessageStreamImpl(mockAppDesc, mockInputOp, mockOutputStream);
        when(mockAppDesc.getIntermediateStream(any(String.class), any(Serde.class), eq(false))).thenReturn(mockPartitionedStream);
        doAnswer(this.getRegisteredTableAnswer()).when(mockAppDesc).getTable(any(RocksDbTableDescriptor.class));
    }
    when(mockJoin.getJoinType()).thenReturn(JoinRelType.INNER);
    SamzaSqlExecutionContext mockExecutionContext = mock(SamzaSqlExecutionContext.class);
    when(mockTranslatorContext.getExecutionContext()).thenReturn(mockExecutionContext);
    SamzaSqlApplicationConfig mockAppConfig = mock(SamzaSqlApplicationConfig.class);
    when(mockExecutionContext.getSamzaSqlApplicationConfig()).thenReturn(mockAppConfig);
    Map<String, SqlIOConfig> ssConfigBySource = mock(HashMap.class);
    when(mockAppConfig.getInputSystemStreamConfigBySource()).thenReturn(ssConfigBySource);
    SqlIOConfig mockIOConfig = mock(SqlIOConfig.class);
    TableDescriptor mockTableDesc;
    if (isRemoteTable) {
        mockTableDesc = mock(RemoteTableDescriptor.class);
    } else {
        mockTableDesc = mock(RocksDbTableDescriptor.class);
    }
    when(ssConfigBySource.get(String.join(".", qualifiedTableName))).thenReturn(mockIOConfig);
    when(mockIOConfig.getTableDescriptor()).thenReturn(Optional.of(mockTableDesc));
    JoinTranslator joinTranslator = new JoinTranslator(logicalOpId, "", queryId);
    // Verify Metrics Works with Join
    Context mockContext = mock(Context.class);
    ContainerContext mockContainerContext = mock(ContainerContext.class);
    TestMetricsRegistryImpl testMetricsRegistryImpl = new TestMetricsRegistryImpl();
    when(mockContext.getContainerContext()).thenReturn(mockContainerContext);
    when(mockContainerContext.getContainerMetricsRegistry()).thenReturn(testMetricsRegistryImpl);
    TranslatorInputMetricsMapFunction inputMetricsMF = joinTranslator.getInputMetricsMF();
    assertNotNull(inputMetricsMF);
    inputMetricsMF.init(mockContext);
    TranslatorOutputMetricsMapFunction outputMetricsMF = joinTranslator.getOutputMetricsMF();
    assertNotNull(outputMetricsMF);
    outputMetricsMF.init(mockContext);
    assertEquals(1, testMetricsRegistryImpl.getCounters().size());
    assertEquals(2, testMetricsRegistryImpl.getCounters().get(logicalOpId).size());
    assertEquals(0, testMetricsRegistryImpl.getCounters().get(logicalOpId).get(0).getCount());
    assertEquals(0, testMetricsRegistryImpl.getCounters().get(logicalOpId).get(1).getCount());
    assertEquals(1, testMetricsRegistryImpl.getGauges().size());
    // Apply translate() method to verify that we are getting the correct map operator constructed
    joinTranslator.translate(mockJoin, mockTranslatorContext);
    // make sure that context has been registered with LogicFilter and output message streams
    verify(mockTranslatorContext, times(1)).registerMessageStream(3, this.getRegisteredMessageStream(3));
    when(mockTranslatorContext.getRelNode(3)).thenReturn(mockJoin);
    when(mockTranslatorContext.getMessageStream(3)).thenReturn(this.getRegisteredMessageStream(3));
    StreamTableJoinOperatorSpec joinSpec = (StreamTableJoinOperatorSpec) Whitebox.getInternalState(this.getRegisteredMessageStream(3), "operatorSpec");
    assertNotNull(joinSpec);
    assertEquals(joinSpec.getOpCode(), OperatorSpec.OpCode.JOIN);
    // Verify joinSpec has the corresponding setup
    StreamTableJoinFunction joinFn = joinSpec.getJoinFn();
    assertNotNull(joinFn);
    if (isRemoteTable) {
        assertTrue(joinFn instanceof SamzaSqlRemoteTableJoinFunction);
    } else {
        assertTrue(joinFn instanceof SamzaSqlLocalTableJoinFunction);
    }
    assertTrue(Whitebox.getInternalState(joinFn, "isTablePosOnRight").equals(false));
    assertEquals(Collections.singletonList(0), Whitebox.getInternalState(joinFn, "streamFieldIds"));
    assertEquals(leftFieldNames, Whitebox.getInternalState(joinFn, "tableFieldNames"));
    List<String> outputFieldNames = new ArrayList<>();
    outputFieldNames.addAll(leftFieldNames);
    outputFieldNames.addAll(rightStreamFieldNames);
    assertEquals(outputFieldNames, Whitebox.getInternalState(joinFn, "outFieldNames"));
}

Example 4 with SamzaSqlExecutionContext

use of org.apache.samza.sql.data.SamzaSqlExecutionContext in project samza by apache.

the class TestProjectTranslator method testTranslate.

@Test
public void testTranslate() throws IOException, ClassNotFoundException {
    // setup mock values to the constructor of FilterTranslator
    LogicalProject mockProject = PowerMockito.mock(LogicalProject.class);
    Context mockContext = mock(Context.class);
    ContainerContext mockContainerContext = mock(ContainerContext.class);
    TranslatorContext mockTranslatorContext = mock(TranslatorContext.class);
    TestMetricsRegistryImpl testMetricsRegistryImpl = new TestMetricsRegistryImpl();
    RelNode mockInput = mock(RelNode.class);
    List<RelNode> inputs = new ArrayList<>();
    inputs.add(mockInput);
    when(mockInput.getId()).thenReturn(1);
    when(mockProject.getId()).thenReturn(2);
    when(mockProject.getInputs()).thenReturn(inputs);
    when(mockProject.getInput()).thenReturn(mockInput);
    RelDataType mockRowType = mock(RelDataType.class);
    when(mockRowType.getFieldCount()).thenReturn(1);
    when(mockProject.getRowType()).thenReturn(mockRowType);
    RexNode mockRexField = mock(RexNode.class);
    List<Pair<RexNode, String>> namedProjects = new ArrayList<>();
    namedProjects.add(Pair.of(mockRexField, "test_field"));
    when(mockProject.getNamedProjects()).thenReturn(namedProjects);
    StreamApplicationDescriptorImpl mockAppDesc = mock(StreamApplicationDescriptorImpl.class);
    OperatorSpec<Object, SamzaSqlRelMessage> mockInputOp = mock(OperatorSpec.class);
    MessageStream<SamzaSqlRelMessage> mockStream = new MessageStreamImpl<>(mockAppDesc, mockInputOp);
    when(mockTranslatorContext.getMessageStream(eq(1))).thenReturn(mockStream);
    doAnswer(this.getRegisterMessageStreamAnswer()).when(mockTranslatorContext).registerMessageStream(eq(2), any(MessageStream.class));
    RexToJavaCompiler mockCompiler = mock(RexToJavaCompiler.class);
    when(mockTranslatorContext.getExpressionCompiler()).thenReturn(mockCompiler);
    Expression mockExpr = mock(Expression.class);
    when(mockCompiler.compile(any(), any())).thenReturn(mockExpr);
    when(mockContext.getContainerContext()).thenReturn(mockContainerContext);
    when(mockContainerContext.getContainerMetricsRegistry()).thenReturn(testMetricsRegistryImpl);
    // Apply translate() method to verify that we are getting the correct map operator constructed
    ProjectTranslator projectTranslator = new ProjectTranslator(1);
    projectTranslator.translate(mockProject, LOGICAL_OP_ID, mockTranslatorContext);
    // make sure that context has been registered with LogicFilter and output message streams
    verify(mockTranslatorContext, times(1)).registerRelNode(2, mockProject);
    verify(mockTranslatorContext, times(1)).registerMessageStream(2, this.getRegisteredMessageStream(2));
    when(mockTranslatorContext.getRelNode(2)).thenReturn(mockProject);
    when(mockTranslatorContext.getMessageStream(2)).thenReturn(this.getRegisteredMessageStream(2));
    StreamOperatorSpec projectSpec = (StreamOperatorSpec) Whitebox.getInternalState(this.getRegisteredMessageStream(2), "operatorSpec");
    assertNotNull(projectSpec);
    assertEquals(projectSpec.getOpCode(), OperatorSpec.OpCode.MAP);
    // Verify that the bootstrap() method will establish the context for the map function
    Map<Integer, TranslatorContext> mockContexts = new HashMap<>();
    mockContexts.put(1, mockTranslatorContext);
    when(mockContext.getApplicationTaskContext()).thenReturn(new SamzaSqlApplicationContext(mockContexts));
    projectSpec.getTransformFn().init(mockContext);
    MapFunction mapFn = (MapFunction) Whitebox.getInternalState(projectSpec, "mapFn");
    assertNotNull(mapFn);
    assertEquals(mockTranslatorContext, Whitebox.getInternalState(mapFn, "translatorContext"));
    assertEquals(mockProject, Whitebox.getInternalState(mapFn, "project"));
    assertEquals(mockExpr, Whitebox.getInternalState(mapFn, "expr"));
    // Verify TestMetricsRegistryImpl works with Project
    assertEquals(1, testMetricsRegistryImpl.getGauges().size());
    assertEquals(2, testMetricsRegistryImpl.getGauges().get(LOGICAL_OP_ID).size());
    assertEquals(1, testMetricsRegistryImpl.getCounters().size());
    assertEquals(2, testMetricsRegistryImpl.getCounters().get(LOGICAL_OP_ID).size());
    assertEquals(0, testMetricsRegistryImpl.getCounters().get(LOGICAL_OP_ID).get(0).getCount());
    assertEquals(0, testMetricsRegistryImpl.getCounters().get(LOGICAL_OP_ID).get(1).getCount());
    // Calling mapFn.apply() to verify the filter function is correctly applied to the input message
    SamzaSqlRelMessage mockInputMsg = new SamzaSqlRelMessage(new ArrayList<>(), new ArrayList<>(), new SamzaSqlRelMsgMetadata(0L, 0L));
    SamzaSqlExecutionContext executionContext = mock(SamzaSqlExecutionContext.class);
    DataContext dataContext = mock(DataContext.class);
    when(mockTranslatorContext.getExecutionContext()).thenReturn(executionContext);
    when(mockTranslatorContext.getDataContext()).thenReturn(dataContext);
    Object[] result = new Object[1];
    final Object mockFieldObj = new Object();
    doAnswer(invocation -> {
        Object[] retValue = invocation.getArgumentAt(4, Object[].class);
        retValue[0] = mockFieldObj;
        return null;
    }).when(mockExpr).execute(eq(executionContext), eq(mockContext), eq(dataContext), eq(mockInputMsg.getSamzaSqlRelRecord().getFieldValues().toArray()), eq(result));
    SamzaSqlRelMessage retMsg = (SamzaSqlRelMessage) mapFn.apply(mockInputMsg);
    assertEquals(retMsg.getSamzaSqlRelRecord().getFieldNames(), Collections.singletonList("test_field"));
    assertEquals(retMsg.getSamzaSqlRelRecord().getFieldValues(), Collections.singletonList(mockFieldObj));
    // Verify mapFn.apply() updates the TestMetricsRegistryImpl metrics
    assertEquals(1, testMetricsRegistryImpl.getCounters().get(LOGICAL_OP_ID).get(0).getCount());
    assertEquals(1, testMetricsRegistryImpl.getCounters().get(LOGICAL_OP_ID).get(1).getCount());
}

Example 5 with SamzaSqlExecutionContext

use of org.apache.samza.sql.data.SamzaSqlExecutionContext in project samza by apache.

the class SamzaSqlApplication method describe.

@Override
public void describe(StreamApplicationDescriptor appDescriptor) {
    try {
        // TODO: Introduce an API to return a dsl string containing one or more sql statements.
        List<String> dslStmts = SamzaSqlDslConverter.fetchSqlFromConfig(appDescriptor.getConfig());
        Map<Integer, TranslatorContext> translatorContextMap = new HashMap<>();
        // 1. Get Calcite plan
        List<String> inputSystemStreams = new LinkedList<>();
        List<String> outputSystemStreams = new LinkedList<>();
        Collection<RelRoot> relRoots = SamzaSqlApplicationConfig.populateSystemStreamsAndGetRelRoots(dslStmts, appDescriptor.getConfig(), inputSystemStreams, outputSystemStreams);
        // 2. Populate configs
        SamzaSqlApplicationConfig sqlConfig = new SamzaSqlApplicationConfig(appDescriptor.getConfig(), inputSystemStreams, outputSystemStreams);
        // 3. Translate Calcite plan to Samza stream operators
        QueryTranslator queryTranslator = new QueryTranslator(appDescriptor, sqlConfig);
        SamzaSqlExecutionContext executionContext = new SamzaSqlExecutionContext(sqlConfig);
        // QueryId implies the index of the query in multiple query statements scenario. It should always start with 0.
        int queryId = 0;
        for (RelRoot relRoot : relRoots) {
            LOG.info("Translating relRoot {} to samza stream graph with queryId {}", relRoot, queryId);
            TranslatorContext translatorContext = new TranslatorContext(appDescriptor, relRoot, executionContext);
            translatorContextMap.put(queryId, translatorContext);
            queryTranslator.translate(relRoot, sqlConfig.getOutputSystemStreams().get(queryId), translatorContext, queryId);
            queryId++;
        }
        // 4. Set all translator contexts
        /*
       * TODO When serialization of ApplicationDescriptor is actually needed, then something will need to be updated here,
       * since translatorContext is not Serializable. Currently, a new ApplicationDescriptor instance is created in each
       * container, so it does not need to be serialized. Therefore, the translatorContext is recreated in each container
       * and does not need to be serialized.
       */
        appDescriptor.withApplicationTaskContextFactory(new ApplicationTaskContextFactory<SamzaSqlApplicationContext>() {

            @Override
            public SamzaSqlApplicationContext create(ExternalContext externalContext, JobContext jobContext, ContainerContext containerContext, TaskContext taskContext, ApplicationContainerContext applicationContainerContext) {
                return new SamzaSqlApplicationContext(translatorContextMap);
            }
        });
    } catch (RuntimeException e) {
        LOG.error("SamzaSqlApplication threw exception.", e);
        throw e;
    }
}