org.apache.druid.catalog.model.table

Class BaseInputSourceDefn

java.lang.Object

org.apache.druid.catalog.model.table.BaseInputSourceDefn

All Implemented Interfaces:

InputSourceDefn

Direct Known Subclasses:

FormattedInputSourceDefn

public abstract class BaseInputSourceDefn
extends Object
implements InputSourceDefn

Base class for input source definitions.

See Also:

FormattedInputSourceDefn} for the base class for (most) input formats which take an input format.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
class	BaseInputSourceDefn.AdHocTableFunction The "from-scratch" table function for this input source.
class	BaseInputSourceDefn.PartialTableFunction The "partial" table function that starts with a catalog external table spec, then uses SQL function arguments to "complete" (i.e.

Constructor Summary

Constructors

Constructor and Description
BaseInputSourceDefn()

Method Summary

Modifier and Type	Method and Description
TableFunction	adHocTableFn() Provide a definition for a SQL table function that defines an ad-hoc external table "from scratch" for this input source.
protected void	auditInputSource(Map<String,Object> jsonMap) Optional step to audit or adjust the input source properties prior to conversion via Jackson.
void	bind(TableDefnRegistry registry) Gather information about the set of format definitions.
protected InputFormat	convertArgsToFormat(Map<String,Object> args, List<ColumnSpec> columns, com.fasterxml.jackson.databind.ObjectMapper jsonMapper) Convert SQL arguments, and the column schema, to an input format, if required.
protected InputSource	convertArgsToSource(Map<String,Object> args, com.fasterxml.jackson.databind.ObjectMapper jsonMapper) Convert the input source using arguments to a "from scratch" table function.
protected abstract void	convertArgsToSourceMap(Map<String,Object> jsonMap, Map<String,Object> args) Convert SQL arguments to the corresponding "generic JSON" form in the given map.
protected ExternalTableSpec	convertArgsToTable(Map<String,Object> args, List<ColumnSpec> columns, com.fasterxml.jackson.databind.ObjectMapper jsonMapper) Define a table "from scratch" using SQL function arguments.
protected abstract ExternalTableSpec	convertCompletedTable(ResolvedExternalTable table, Map<String,Object> args, List<ColumnSpec> columns) Complete a partial table using the table function arguments and columns provided.
protected InputSource	convertSource(Map<String,Object> jsonMap, com.fasterxml.jackson.databind.ObjectMapper jsonMapper) Convert from a generic Java map to the target input source using the object mapper provided.
ExternalTableSpec	convertTable(ResolvedExternalTable table) Convert a complete (that is, fully-defined) table spec to an external table spec.
protected abstract InputFormat	convertTableToFormat(ResolvedExternalTable table) Convert the format spec, if any, to an input format.
protected InputSource	convertTableToSource(ResolvedExternalTable table) Converts the input source given in a table spec.
protected abstract BaseInputSourceDefn.AdHocTableFunction	defineAdHocTableFunction() Overridden by each subclass to define the parameters needed by each input source.
protected abstract Class<? extends InputSource>	inputSourceClass() Overridden by each subclass to return the input source class to be used for JSON conversions.
protected List<ColumnSpec>	selectPartialTableColumns(ResolvedExternalTable table, List<ColumnSpec> columns) Choose table or SQL-provided columns: table takes precedence.
void	validate(ResolvedExternalTable table) Given a external table catalog spec, with the JSON input source and format properties parsed to generic Java maps, validate that the properties are valid prior to saving the spec into the catalog.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface org.apache.druid.catalog.model.table.InputSourceDefn

partialTableFn, typeValue

Constructor Detail

BaseInputSourceDefn

public BaseInputSourceDefn()

Method Detail

inputSourceClass

protected abstract Class<? extends InputSource> inputSourceClass()

Overridden by each subclass to return the input source class to be used for JSON conversions.

bind

public void bind(TableDefnRegistry registry)

Description copied from interface: InputSourceDefn

Gather information about the set of format definitions.

Specified by:

bind in interface InputSourceDefn

validate

public void validate(ResolvedExternalTable table)

Description copied from interface: InputSourceDefn

Given a external table catalog spec, with the JSON input source and format properties parsed to generic Java maps, validate that the properties are valid prior to saving the spec into the catalog.

Specified by:

validate in interface InputSourceDefn

Parameters:

table - a catalog table spec with the input source and input format properties parsed into generic Java maps

defineAdHocTableFunction

protected abstract BaseInputSourceDefn.AdHocTableFunction defineAdHocTableFunction()

Overridden by each subclass to define the parameters needed by each input source.

adHocTableFn

public TableFunction adHocTableFn()

Description copied from interface: InputSourceDefn

Provide a definition for a SQL table function that defines an ad-hoc external table "from scratch" for this input source. Typically defines parameters for the input source and all allowed input formats.

Specified by:

adHocTableFn in interface InputSourceDefn

Returns:

a fully-defined external table to be handed off to the Calcite planner.

convertArgsToTable

protected ExternalTableSpec convertArgsToTable(Map<String,Object> args,
                                               List<ColumnSpec> columns,
                                               com.fasterxml.jackson.databind.ObjectMapper jsonMapper)

Define a table "from scratch" using SQL function arguments.

convertArgsToSource

protected InputSource convertArgsToSource(Map<String,Object> args,
                                          com.fasterxml.jackson.databind.ObjectMapper jsonMapper)

Convert the input source using arguments to a "from scratch" table function.

convertArgsToSourceMap

protected abstract void convertArgsToSourceMap(Map<String,Object> jsonMap,
                                               Map<String,Object> args)

Convert SQL arguments to the corresponding "generic JSON" form in the given map. The map will then be adjusted and converted to the actual input source.

convertArgsToFormat

protected InputFormat convertArgsToFormat(Map<String,Object> args,
                                          List<ColumnSpec> columns,
                                          com.fasterxml.jackson.databind.ObjectMapper jsonMapper)

Convert SQL arguments, and the column schema, to an input format, if required.

convertCompletedTable

protected abstract ExternalTableSpec convertCompletedTable(ResolvedExternalTable table,
                                                           Map<String,Object> args,
                                                           List<ColumnSpec> columns)

Complete a partial table using the table function arguments and columns provided. The arguments match the set of parameters used for the function. The columns are provided if the SQL included an EXTENDS clause: the implementation should decide if columns are required (or allowed) depending on whether the partial spec already defines columns.

Parameters:

table - the partial table spec, with input source and format parsed into a generic Java map

args - the argument values provided in the SQL table function call. The arguments use the Java types defined in the parameter definitions.

columns - the set of columns (if any) from the SQL EXTEND clause

Returns:

an external table spec which Calcite can consume

convertTable

public ExternalTableSpec convertTable(ResolvedExternalTable table)

Description copied from interface: InputSourceDefn

Convert a complete (that is, fully-defined) table spec to an external table spec. Used when SQL references the catalog table directly by name in the FROM clause without using a table function.

Specified by:

convertTable in interface InputSourceDefn

Returns:

a fully-defined external table to be handed off to the Calcite planner.

convertTableToSource

protected InputSource convertTableToSource(ResolvedExternalTable table)

Converts the input source given in a table spec. Since Druid input sources were not designed for the use by the catalog or SQL, some cleanup is done to simplify the parameters which the user provides.

Parameters:

table - the resolved external table spec

Returns:

the input source converted from the spec

convertSource

protected InputSource convertSource(Map<String,Object> jsonMap,
                                    com.fasterxml.jackson.databind.ObjectMapper jsonMapper)

Convert from a generic Java map to the target input source using the object mapper provided. Translates Jackson errors into a generic unchecked error.

auditInputSource

protected void auditInputSource(Map<String,Object> jsonMap)

Optional step to audit or adjust the input source properties prior to conversion via Jackson. Changes are made directly in the jsonMap.

convertTableToFormat

protected abstract InputFormat convertTableToFormat(ResolvedExternalTable table)

Convert the format spec, if any, to an input format.

selectPartialTableColumns

protected List<ColumnSpec> selectPartialTableColumns(ResolvedExternalTable table,
                                                     List<ColumnSpec> columns)

Choose table or SQL-provided columns: table takes precedence.