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id | title |
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data-formats | Data formats |
Apache Druid can ingest denormalized data in JSON, CSV, or a delimited form such as TSV, or any custom format. While most examples in the documentation use data in JSON format, it is not difficult to configure Druid to ingest any other delimited data. We welcome any contributions to new formats.
This page lists all default and core extension data formats supported by Druid. For additional data formats supported with community extensions, please see our community extensions list.
Formatting the Data
The following samples show data formats that are natively supported in Druid:
JSON
{"timestamp": "2013-08-31T01:02:33Z", "page": "Gypsy Danger", "language" : "en", "user" : "nuclear", "unpatrolled" : "true", "newPage" : "true", "robot": "false", "anonymous": "false", "namespace":"article", "continent":"North America", "country":"United States", "region":"Bay Area", "city":"San Francisco", "added": 57, "deleted": 200, "delta": -143}
{"timestamp": "2013-08-31T03:32:45Z", "page": "Striker Eureka", "language" : "en", "user" : "speed", "unpatrolled" : "false", "newPage" : "true", "robot": "true", "anonymous": "false", "namespace":"wikipedia", "continent":"Australia", "country":"Australia", "region":"Cantebury", "city":"Syndey", "added": 459, "deleted": 129, "delta": 330}
{"timestamp": "2013-08-31T07:11:21Z", "page": "Cherno Alpha", "language" : "ru", "user" : "masterYi", "unpatrolled" : "false", "newPage" : "true", "robot": "true", "anonymous": "false", "namespace":"article", "continent":"Asia", "country":"Russia", "region":"Oblast", "city":"Moscow", "added": 123, "deleted": 12, "delta": 111}
{"timestamp": "2013-08-31T11:58:39Z", "page": "Crimson Typhoon", "language" : "zh", "user" : "triplets", "unpatrolled" : "true", "newPage" : "false", "robot": "true", "anonymous": "false", "namespace":"wikipedia", "continent":"Asia", "country":"China", "region":"Shanxi", "city":"Taiyuan", "added": 905, "deleted": 5, "delta": 900}
{"timestamp": "2013-08-31T12:41:27Z", "page": "Coyote Tango", "language" : "ja", "user" : "cancer", "unpatrolled" : "true", "newPage" : "false", "robot": "true", "anonymous": "false", "namespace":"wikipedia", "continent":"Asia", "country":"Japan", "region":"Kanto", "city":"Tokyo", "added": 1, "deleted": 10, "delta": -9}
CSV
2013-08-31T01:02:33Z,"Gypsy Danger","en","nuclear","true","true","false","false","article","North America","United States","Bay Area","San Francisco",57,200,-143
2013-08-31T03:32:45Z,"Striker Eureka","en","speed","false","true","true","false","wikipedia","Australia","Australia","Cantebury","Syndey",459,129,330
2013-08-31T07:11:21Z,"Cherno Alpha","ru","masterYi","false","true","true","false","article","Asia","Russia","Oblast","Moscow",123,12,111
2013-08-31T11:58:39Z,"Crimson Typhoon","zh","triplets","true","false","true","false","wikipedia","Asia","China","Shanxi","Taiyuan",905,5,900
2013-08-31T12:41:27Z,"Coyote Tango","ja","cancer","true","false","true","false","wikipedia","Asia","Japan","Kanto","Tokyo",1,10,-9
TSV (Delimited)
2013-08-31T01:02:33Z "Gypsy Danger" "en" "nuclear" "true" "true" "false" "false" "article" "North America" "United States" "Bay Area" "San Francisco" 57 200 -143
2013-08-31T03:32:45Z "Striker Eureka" "en" "speed" "false" "true" "true" "false" "wikipedia" "Australia" "Australia" "Cantebury" "Syndey" 459 129 330
2013-08-31T07:11:21Z "Cherno Alpha" "ru" "masterYi" "false" "true" "true" "false" "article" "Asia" "Russia" "Oblast" "Moscow" 123 12 111
2013-08-31T11:58:39Z "Crimson Typhoon" "zh" "triplets" "true" "false" "true" "false" "wikipedia" "Asia" "China" "Shanxi" "Taiyuan" 905 5 900
2013-08-31T12:41:27Z "Coyote Tango" "ja" "cancer" "true" "false" "true" "false" "wikipedia" "Asia" "Japan" "Kanto" "Tokyo" 1 10 -9
Note that the CSV and TSV data do not contain column heads. This becomes important when you specify the data for ingesting.
Besides text formats, Druid also supports binary formats such as Orc and Parquet formats.
Custom Formats
Druid supports custom data formats and can use the Regex
parser or the JavaScript
parsers to parse these formats. Please note that using any of these parsers for
parsing data will not be as efficient as writing a native Java parser or using an external stream processor. We welcome contributions of new Parsers.
Input Format
The Input Format is a new way to specify the data format of your input data which was introduced in 0.17.0. Unfortunately, the Input Format doesn't support all data formats or ingestion methods supported by Druid yet. Especially if you want to use the Hadoop ingestion, you still need to use the Parser. If your data is formatted in some format not listed in this section, please consider using the Parser instead.
All forms of Druid ingestion require some form of schema object. The format of the data to be ingested is specified using the inputFormat
entry in your ioConfig
.
JSON
The inputFormat
to load data of JSON format. An example is:
"ioConfig": {
"inputFormat": {
"type": "json"
},
...
}
The JSON inputFormat
has the following components:
Field | Type | Description | Required |
---|---|---|---|
type | String | This should say json . |
yes |
flattenSpec | JSON Object | Specifies flattening configuration for nested JSON data. See flattenSpec for more info. |
no |
featureSpec | JSON Object | JSON parser features supported by Jackson library. Those features will be applied when parsing the input JSON data. | no |
CSV
The inputFormat
to load data of the CSV format. An example is:
"ioConfig": {
"inputFormat": {
"type": "csv",
"columns" : ["timestamp","page","language","user","unpatrolled","newPage","robot","anonymous","namespace","continent","country","region","city","added","deleted","delta"]
},
...
}
The CSV inputFormat
has the following components:
Field | Type | Description | Required |
---|---|---|---|
type | String | This should say csv . |
yes |
listDelimiter | String | A custom delimiter for multi-value dimensions. | no (default = ctrl+A) |
columns | JSON array | Specifies the columns of the data. The columns should be in the same order with the columns of your data. | yes if findColumnsFromHeader is false or missing |
findColumnsFromHeader | Boolean | If this is set, the task will find the column names from the header row. Note that skipHeaderRows will be applied before finding column names from the header. For example, if you set skipHeaderRows to 2 and findColumnsFromHeader to true, the task will skip the first two lines and then extract column information from the third line. columns will be ignored if this is set to true. |
no (default = false if columns is set; otherwise null) |
skipHeaderRows | Integer | If this is set, the task will skip the first skipHeaderRows rows. |
no (default = 0) |
TSV (Delimited)
"ioConfig": {
"inputFormat": {
"type": "tsv",
"columns" : ["timestamp","page","language","user","unpatrolled","newPage","robot","anonymous","namespace","continent","country","region","city","added","deleted","delta"],
"delimiter":"|"
},
...
}
The inputFormat
to load data of a delimited format. An example is:
Field | Type | Description | Required |
---|---|---|---|
type | String | This should say tsv . |
yes |
delimiter | String | A custom delimiter for data values. | no (default = \t ) |
listDelimiter | String | A custom delimiter for multi-value dimensions. | no (default = ctrl+A) |
columns | JSON array | Specifies the columns of the data. The columns should be in the same order with the columns of your data. | yes if findColumnsFromHeader is false or missing |
findColumnsFromHeader | Boolean | If this is set, the task will find the column names from the header row. Note that skipHeaderRows will be applied before finding column names from the header. For example, if you set skipHeaderRows to 2 and findColumnsFromHeader to true, the task will skip the first two lines and then extract column information from the third line. columns will be ignored if this is set to true. |
no (default = false if columns is set; otherwise null) |
skipHeaderRows | Integer | If this is set, the task will skip the first skipHeaderRows rows. |
no (default = 0) |
Be sure to change the delimiter
to the appropriate delimiter for your data. Like CSV, you must specify the columns and which subset of the columns you want indexed.
ORC
You need to include the
druid-orc-extensions
as an extension to use the ORC input format.
If you are considering upgrading from earlier than 0.15.0 to 0.15.0 or a higher version, please read Migration from 'contrib' extension carefully.
The inputFormat
to load data of ORC format. An example is:
"ioConfig": {
"inputFormat": {
"type": "orc",
"flattenSpec": {
"useFieldDiscovery": true,
"fields": [
{
"type": "path",
"name": "nested",
"expr": "$.path.to.nested"
}
]
}
"binaryAsString": false
},
...
}
The ORC inputFormat
has the following components:
Field | Type | Description | Required |
---|---|---|---|
type | String | This should say orc . |
yes |
flattenSpec | JSON Object | Specifies flattening configuration for nested ORC data. See flattenSpec for more info. |
no |
binaryAsString | Boolean | Specifies if the binary orc column which is not logically marked as a string should be treated as a UTF-8 encoded string. | no (default = false) |
Parquet
You need to include the
druid-parquet-extensions
as an extension to use the Parquet input format.
The inputFormat
to load data of Parquet format. An example is:
"ioConfig": {
"inputFormat": {
"type": "parquet",
"flattenSpec": {
"useFieldDiscovery": true,
"fields": [
{
"type": "path",
"name": "nested",
"expr": "$.path.to.nested"
}
]
}
"binaryAsString": false
},
...
}
The Parquet inputFormat
has the following components:
Field | Type | Description | Required |
---|---|---|---|
type | String | This should be set to parquet to read Parquet file |
yes |
flattenSpec | JSON Object | Define a flattenSpec to extract nested values from a Parquet file. Note that only 'path' expression are supported ('jq' is unavailable). |
no (default will auto-discover 'root' level properties) |
binaryAsString | Boolean | Specifies if the bytes parquet column which is not logically marked as a string or enum type should be treated as a UTF-8 encoded string. | no (default = false) |
FlattenSpec
The flattenSpec
is located in inputFormat
→ flattenSpec
and is responsible for
bridging the gap between potentially nested input data (such as JSON, Avro, etc) and Druid's flat data model.
An example flattenSpec
is:
"flattenSpec": {
"useFieldDiscovery": true,
"fields": [
{ "name": "baz", "type": "root" },
{ "name": "foo_bar", "type": "path", "expr": "$.foo.bar" },
{ "name": "first_food", "type": "jq", "expr": ".thing.food[1]" }
]
}
Conceptually, after input data records are read, the
flattenSpec
is applied first before any other specs such astimestampSpec
,transformSpec
,dimensionsSpec
, ormetricsSpec
. Keep this in mind when writing your ingestion spec.
Flattening is only supported for data formats that support nesting, including avro
, json
, orc
,
and parquet
.
A flattenSpec
can have the following components:
Field | Description | Default |
---|---|---|
useFieldDiscovery | If true, interpret all root-level fields as available fields for usage by timestampSpec , transformSpec , dimensionsSpec , and metricsSpec .If false, only explicitly specified fields (see fields ) will be available for use. |
true |
fields | Specifies the fields of interest and how they are accessed. See below for details. | [] |
Field flattening specifications
Each entry in the fields
list can have the following components:
Field | Description | Default |
---|---|---|
type | Options are as follows:
|
none (required) |
name | Name of the field after flattening. This name can be referred to by the timestampSpec , transformSpec , dimensionsSpec , and metricsSpec . |
none (required) |
expr | Expression for accessing the field while flattening. For type path , this should be JsonPath. For type jq , this should be jackson-jq notation. For other types, this parameter is ignored. |
none (required for types path and jq ) |
Notes on flattening
- For convenience, when defining a root-level field, it is possible to define only the field name, as a string, instead of a JSON object. For example,
{"name": "baz", "type": "root"}
is equivalent to"baz"
. - Enabling
useFieldDiscovery
will only automatically detect "simple" fields at the root level that correspond to data types that Druid supports. This includes strings, numbers, and lists of strings or numbers. Other types will not be automatically detected, and must be specified explicitly in thefields
list. - Duplicate field
name
s are not allowed. An exception will be thrown. - If
useFieldDiscovery
is enabled, any discovered field with the same name as one already defined in thefields
list will be skipped, rather than added twice. - http://jsonpath.herokuapp.com/ is useful for testing
path
-type expressions. - jackson-jq supports a subset of the full jq syntax. Please refer to the jackson-jq documentation for details.
Parser
The Parser is deprecated for native batch tasks, Kafka indexing service, and Kinesis indexing service. Consider using the input format instead for these types of ingestion.
This section lists all default and core extension parsers. For community extension parsers, please see our community extensions list.
String Parser
string
typed parsers operate on text based inputs that can be split into individual records by newlines.
Each line can be further parsed using parseSpec
.
Field | Type | Description | Required |
---|---|---|---|
type | String | This should say string in general, or hadoopyString when used in a Hadoop indexing job. |
yes |
parseSpec | JSON Object | Specifies the format, timestamp, and dimensions of the data. | yes |
Avro Hadoop Parser
You need to include the
druid-avro-extensions
as an extension to use the Avro Hadoop Parser.
This parser is for Hadoop batch ingestion.
The inputFormat
of inputSpec
in ioConfig
must be set to "org.apache.druid.data.input.avro.AvroValueInputFormat"
.
You may want to set Avro reader's schema in jobProperties
in tuningConfig
,
e.g.: "avro.schema.input.value.path": "/path/to/your/schema.avsc"
or
"avro.schema.input.value": "your_schema_JSON_object"
.
If the Avro reader's schema is not set, the schema in Avro object container file will be used.
See Avro specification for more information.
Field | Type | Description | Required |
---|---|---|---|
type | String | This should say avro_hadoop . |
yes |
parseSpec | JSON Object | Specifies the timestamp and dimensions of the data. Should be an "avro" parseSpec. | yes |
An Avro parseSpec can contain a flattenSpec
using either the "root" or "path"
field types, which can be used to read nested Avro records. The "jq" field type is not currently supported for Avro.
For example, using Avro Hadoop parser with custom reader's schema file:
{
"type" : "index_hadoop",
"spec" : {
"dataSchema" : {
"dataSource" : "",
"parser" : {
"type" : "avro_hadoop",
"parseSpec" : {
"format": "avro",
"timestampSpec": <standard timestampSpec>,
"dimensionsSpec": <standard dimensionsSpec>,
"flattenSpec": <optional>
}
}
},
"ioConfig" : {
"type" : "hadoop",
"inputSpec" : {
"type" : "static",
"inputFormat": "org.apache.druid.data.input.avro.AvroValueInputFormat",
"paths" : ""
}
},
"tuningConfig" : {
"jobProperties" : {
"avro.schema.input.value.path" : "/path/to/my/schema.avsc"
}
}
}
}
ORC Hadoop Parser
You need to include the
druid-orc-extensions
as an extension to use the ORC Hadoop Parser.
If you are considering upgrading from earlier than 0.15.0 to 0.15.0 or a higher version, please read Migration from 'contrib' extension carefully.
This parser is for Hadoop batch ingestion.
The inputFormat
of inputSpec
in ioConfig
must be set to "org.apache.orc.mapreduce.OrcInputFormat"
.
Field | Type | Description | Required |
---|---|---|---|
type | String | This should say orc |
yes |
parseSpec | JSON Object | Specifies the timestamp and dimensions of the data (timeAndDims and orc format) and a flattenSpec (orc format) |
yes |
The parser supports two parseSpec
formats: orc
and timeAndDims
.
orc
supports auto field discovery and flattening, if specified with a flattenSpec
.
If no flattenSpec
is specified, useFieldDiscovery
will be enabled by default. Specifying a dimensionSpec
is
optional if useFieldDiscovery
is enabled: if a dimensionSpec
is supplied, the list of dimensions
it defines will be
the set of ingested dimensions, if missing the discovered fields will make up the list.
timeAndDims
parse spec must specify which fields will be extracted as dimensions through the dimensionSpec
.
All column types are supported, with the exception of union
types. Columns of
list
type, if filled with primitives, may be used as a multi-value dimension, or specific elements can be extracted with
flattenSpec
expressions. Likewise, primitive fields may be extracted from map
and struct
types in the same manner.
Auto field discovery will automatically create a string dimension for every (non-timestamp) primitive or list
of
primitives, as well as any flatten expressions defined in the flattenSpec
.
Hadoop job properties
Like most Hadoop jobs, the best outcomes will add "mapreduce.job.user.classpath.first": "true"
or
"mapreduce.job.classloader": "true"
to the jobProperties
section of tuningConfig
. Note that it is likely if using
"mapreduce.job.classloader": "true"
that you will need to set mapreduce.job.classloader.system.classes
to include
-org.apache.hadoop.hive.
to instruct Hadoop to load org.apache.hadoop.hive
classes from the application jars instead
of system jars, e.g.
...
"mapreduce.job.classloader": "true",
"mapreduce.job.classloader.system.classes" : "java., javax.accessibility., javax.activation., javax.activity., javax.annotation., javax.annotation.processing., javax.crypto., javax.imageio., javax.jws., javax.lang.model., -javax.management.j2ee., javax.management., javax.naming., javax.net., javax.print., javax.rmi., javax.script., -javax.security.auth.message., javax.security.auth., javax.security.cert., javax.security.sasl., javax.sound., javax.sql., javax.swing., javax.tools., javax.transaction., -javax.xml.registry., -javax.xml.rpc., javax.xml., org.w3c.dom., org.xml.sax., org.apache.commons.logging., org.apache.log4j., -org.apache.hadoop.hbase., -org.apache.hadoop.hive., org.apache.hadoop., core-default.xml, hdfs-default.xml, mapred-default.xml, yarn-default.xml",
...
This is due to the hive-storage-api
dependency of the
orc-mapreduce
library, which provides some classes under the org.apache.hadoop.hive
package. If instead using the
setting "mapreduce.job.user.classpath.first": "true"
, then this will not be an issue.
Examples
orc
parser, orc
parseSpec, auto field discovery, flatten expressions
{
"type": "index_hadoop",
"spec": {
"ioConfig": {
"type": "hadoop",
"inputSpec": {
"type": "static",
"inputFormat": "org.apache.orc.mapreduce.OrcInputFormat",
"paths": "path/to/file.orc"
},
...
},
"dataSchema": {
"dataSource": "example",
"parser": {
"type": "orc",
"parseSpec": {
"format": "orc",
"flattenSpec": {
"useFieldDiscovery": true,
"fields": [
{
"type": "path",
"name": "nestedDim",
"expr": "$.nestedData.dim1"
},
{
"type": "path",
"name": "listDimFirstItem",
"expr": "$.listDim[1]"
}
]
},
"timestampSpec": {
"column": "timestamp",
"format": "millis"
}
}
},
...
},
"tuningConfig": <hadoop-tuning-config>
}
}
}
orc
parser, orc
parseSpec, field discovery with no flattenSpec or dimensionSpec
{
"type": "index_hadoop",
"spec": {
"ioConfig": {
"type": "hadoop",
"inputSpec": {
"type": "static",
"inputFormat": "org.apache.orc.mapreduce.OrcInputFormat",
"paths": "path/to/file.orc"
},
...
},
"dataSchema": {
"dataSource": "example",
"parser": {
"type": "orc",
"parseSpec": {
"format": "orc",
"timestampSpec": {
"column": "timestamp",
"format": "millis"
}
}
},
...
},
"tuningConfig": <hadoop-tuning-config>
}
}
}
orc
parser, orc
parseSpec, no autodiscovery
{
"type": "index_hadoop",
"spec": {
"ioConfig": {
"type": "hadoop",
"inputSpec": {
"type": "static",
"inputFormat": "org.apache.orc.mapreduce.OrcInputFormat",
"paths": "path/to/file.orc"
},
...
},
"dataSchema": {
"dataSource": "example",
"parser": {
"type": "orc",
"parseSpec": {
"format": "orc",
"flattenSpec": {
"useFieldDiscovery": false,
"fields": [
{
"type": "path",
"name": "nestedDim",
"expr": "$.nestedData.dim1"
},
{
"type": "path",
"name": "listDimFirstItem",
"expr": "$.listDim[1]"
}
]
},
"timestampSpec": {
"column": "timestamp",
"format": "millis"
},
"dimensionsSpec": {
"dimensions": [
"dim1",
"dim3",
"nestedDim",
"listDimFirstItem"
],
"dimensionExclusions": [],
"spatialDimensions": []
}
}
},
...
},
"tuningConfig": <hadoop-tuning-config>
}
}
}
orc
parser, timeAndDims
parseSpec
{
"type": "index_hadoop",
"spec": {
"ioConfig": {
"type": "hadoop",
"inputSpec": {
"type": "static",
"inputFormat": "org.apache.orc.mapreduce.OrcInputFormat",
"paths": "path/to/file.orc"
},
...
},
"dataSchema": {
"dataSource": "example",
"parser": {
"type": "orc",
"parseSpec": {
"format": "timeAndDims",
"timestampSpec": {
"column": "timestamp",
"format": "auto"
},
"dimensionsSpec": {
"dimensions": [
"dim1",
"dim2",
"dim3",
"listDim"
],
"dimensionExclusions": [],
"spatialDimensions": []
}
}
},
...
},
"tuningConfig": <hadoop-tuning-config>
}
}
Parquet Hadoop Parser
You need to include the
druid-parquet-extensions
as an extension to use the Parquet Hadoop Parser.
The Parquet Hadoop parser is for Hadoop batch ingestion and parses Parquet files directly.
The inputFormat
of inputSpec
in ioConfig
must be set to org.apache.druid.data.input.parquet.DruidParquetInputFormat
.
The Parquet Hadoop Parser supports auto field discovery and flattening if provided with a
flattenSpec
with the parquet
parseSpec
. Parquet nested list and map
logical types should operate correctly with
JSON path expressions for all supported types.
Field | Type | Description | Required |
---|---|---|---|
type | String | This should say parquet . |
yes |
parseSpec | JSON Object | Specifies the timestamp and dimensions of the data, and optionally, a flatten spec. Valid parseSpec formats are timeAndDims and parquet |
yes |
binaryAsString | Boolean | Specifies if the bytes parquet column which is not logically marked as a string or enum type should be treated as a UTF-8 encoded string. | no(default = false) |
When the time dimension is a DateType column,
a format should not be supplied. When the format is UTF8 (String), either auto
or a explicitly defined
format is required.
Parquet Hadoop Parser vs Parquet Avro Hadoop Parser
Both parsers read from Parquet files, but slightly differently. The main differences are:
- The Parquet Hadoop Parser uses a simple conversion while the Parquet Avro Hadoop Parser
converts Parquet data into avro records first with the
parquet-avro
library and then parses avro data using thedruid-avro-extensions
module to ingest into Druid. - The Parquet Hadoop Parser sets a hadoop job property
parquet.avro.add-list-element-records
tofalse
(which normally defaults totrue
), in order to 'unwrap' primitive list elements into multi-value dimensions. - The Parquet Hadoop Parser supports
int96
Parquet values, while the Parquet Avro Hadoop Parser does not. There may also be some subtle differences in the behavior of JSON path expression evaluation offlattenSpec
.
Based on those differences, we suggest using the Parquet Hadoop Parser over the Parquet Avro Hadoop Parser to allow ingesting data beyond the schema constraints of Avro conversion. However, the Parquet Avro Hadoop Parser was the original basis for supporting the Parquet format, and as such it is a bit more mature.
Examples
parquet
parser, parquet
parseSpec
{
"type": "index_hadoop",
"spec": {
"ioConfig": {
"type": "hadoop",
"inputSpec": {
"type": "static",
"inputFormat": "org.apache.druid.data.input.parquet.DruidParquetInputFormat",
"paths": "path/to/file.parquet"
},
...
},
"dataSchema": {
"dataSource": "example",
"parser": {
"type": "parquet",
"parseSpec": {
"format": "parquet",
"flattenSpec": {
"useFieldDiscovery": true,
"fields": [
{
"type": "path",
"name": "nestedDim",
"expr": "$.nestedData.dim1"
},
{
"type": "path",
"name": "listDimFirstItem",
"expr": "$.listDim[1]"
}
]
},
"timestampSpec": {
"column": "timestamp",
"format": "auto"
},
"dimensionsSpec": {
"dimensions": [],
"dimensionExclusions": [],
"spatialDimensions": []
}
}
},
...
},
"tuningConfig": <hadoop-tuning-config>
}
}
}
parquet
parser, timeAndDims
parseSpec
{
"type": "index_hadoop",
"spec": {
"ioConfig": {
"type": "hadoop",
"inputSpec": {
"type": "static",
"inputFormat": "org.apache.druid.data.input.parquet.DruidParquetInputFormat",
"paths": "path/to/file.parquet"
},
...
},
"dataSchema": {
"dataSource": "example",
"parser": {
"type": "parquet",
"parseSpec": {
"format": "timeAndDims",
"timestampSpec": {
"column": "timestamp",
"format": "auto"
},
"dimensionsSpec": {
"dimensions": [
"dim1",
"dim2",
"dim3",
"listDim"
],
"dimensionExclusions": [],
"spatialDimensions": []
}
}
},
...
},
"tuningConfig": <hadoop-tuning-config>
}
}
Parquet Avro Hadoop Parser
Consider using the Parquet Hadoop Parser over this parser to ingest Parquet files. See Parquet Hadoop Parser vs Parquet Avro Hadoop Parser for the differences between those parsers.
You need to include both the
druid-parquet-extensions
[druid-avro-extensions
] as extensions to use the Parquet Avro Hadoop Parser.
The Parquet Avro Hadoop Parser is for Hadoop batch ingestion.
This parser first converts the Parquet data into Avro records, and then parses them to ingest into Druid.
The inputFormat
of inputSpec
in ioConfig
must be set to org.apache.druid.data.input.parquet.DruidParquetAvroInputFormat
.
The Parquet Avro Hadoop Parser supports auto field discovery and flattening if provided with a
flattenSpec
with the avro
parseSpec
. Parquet nested list and map
logical types should operate correctly with
JSON path expressions for all supported types. This parser sets a hadoop job property
parquet.avro.add-list-element-records
to false
(which normally defaults to true
), in order to 'unwrap' primitive
list elements into multi-value dimensions.
Note that the int96
Parquet value type is not supported with this parser.
Field | Type | Description | Required |
---|---|---|---|
type | String | This should say parquet-avro . |
yes |
parseSpec | JSON Object | Specifies the timestamp and dimensions of the data, and optionally, a flatten spec. Should be avro . |
yes |
binaryAsString | Boolean | Specifies if the bytes parquet column which is not logically marked as a string or enum type should be treated as a UTF-8 encoded string. | no(default = false) |
When the time dimension is a DateType column,
a format should not be supplied. When the format is UTF8 (String), either auto
or
an explicitly defined format is required.
Example
{
"type": "index_hadoop",
"spec": {
"ioConfig": {
"type": "hadoop",
"inputSpec": {
"type": "static",
"inputFormat": "org.apache.druid.data.input.parquet.DruidParquetAvroInputFormat",
"paths": "path/to/file.parquet"
},
...
},
"dataSchema": {
"dataSource": "example",
"parser": {
"type": "parquet-avro",
"parseSpec": {
"format": "avro",
"flattenSpec": {
"useFieldDiscovery": true,
"fields": [
{
"type": "path",
"name": "nestedDim",
"expr": "$.nestedData.dim1"
},
{
"type": "path",
"name": "listDimFirstItem",
"expr": "$.listDim[1]"
}
]
},
"timestampSpec": {
"column": "timestamp",
"format": "auto"
},
"dimensionsSpec": {
"dimensions": [],
"dimensionExclusions": [],
"spatialDimensions": []
}
}
},
...
},
"tuningConfig": <hadoop-tuning-config>
}
}
}
Avro Stream Parser
You need to include the
druid-avro-extensions
as an extension to use the Avro Stream Parser.
This parser is for stream ingestion and reads Avro data from a stream directly.
Field | Type | Description | Required |
---|---|---|---|
type | String | This should say avro_stream . |
no |
avroBytesDecoder | JSON Object | Specifies how to decode bytes to Avro record. | yes |
parseSpec | JSON Object | Specifies the timestamp and dimensions of the data. Should be an "avro" parseSpec. | yes |
An Avro parseSpec can contain a flattenSpec
using either the "root" or "path"
field types, which can be used to read nested Avro records. The "jq" field type is not currently supported for Avro.
For example, using Avro stream parser with schema repo Avro bytes decoder:
"parser" : {
"type" : "avro_stream",
"avroBytesDecoder" : {
"type" : "schema_repo",
"subjectAndIdConverter" : {
"type" : "avro_1124",
"topic" : "${YOUR_TOPIC}"
},
"schemaRepository" : {
"type" : "avro_1124_rest_client",
"url" : "${YOUR_SCHEMA_REPO_END_POINT}",
}
},
"parseSpec" : {
"format": "avro",
"timestampSpec": <standard timestampSpec>,
"dimensionsSpec": <standard dimensionsSpec>,
"flattenSpec": <optional>
}
}
Avro Bytes Decoder
If type
is not included, the avroBytesDecoder defaults to schema_repo
.
Inline Schema Based Avro Bytes Decoder
The "schema_inline" decoder reads Avro records using a fixed schema and does not support schema migration. If you may need to migrate schemas in the future, consider one of the other decoders, all of which use a message header that allows the parser to identify the proper Avro schema for reading records.
This decoder can be used if all the input events can be read using the same schema. In this case, specify the schema in the input task JSON itself, as described below.
...
"avroBytesDecoder": {
"type": "schema_inline",
"schema": {
//your schema goes here, for example
"namespace": "org.apache.druid.data",
"name": "User",
"type": "record",
"fields": [
{ "name": "FullName", "type": "string" },
{ "name": "Country", "type": "string" }
]
}
}
...
Multiple Inline Schemas Based Avro Bytes Decoder
Use this decoder if different input events can have different read schemas. In this case, specify the schema in the input task JSON itself, as described below.
...
"avroBytesDecoder": {
"type": "multiple_schemas_inline",
"schemas": {
//your id -> schema map goes here, for example
"1": {
"namespace": "org.apache.druid.data",
"name": "User",
"type": "record",
"fields": [
{ "name": "FullName", "type": "string" },
{ "name": "Country", "type": "string" }
]
},
"2": {
"namespace": "org.apache.druid.otherdata",
"name": "UserIdentity",
"type": "record",
"fields": [
{ "name": "Name", "type": "string" },
{ "name": "Location", "type": "string" }
]
},
...
...
}
}
...
Note that it is essentially a map of integer schema ID to avro schema object. This parser assumes that record has following format. first 1 byte is version and must always be 1. next 4 bytes are integer schema ID serialized using big-endian byte order. remaining bytes contain serialized avro message.
SchemaRepo Based Avro Bytes Decoder
This Avro bytes decoder first extracts subject
and id
from the input message bytes, and then uses them to look up the Avro schema used to decode the Avro record from bytes. For details, see the schema repo and AVRO-1124. You will need an http service like schema repo to hold the avro schema. For information on registering a schema on the message producer side, see org.apache.druid.data.input.AvroStreamInputRowParserTest#testParse()
.
Field | Type | Description | Required |
---|---|---|---|
type | String | This should say schema_repo . |
no |
subjectAndIdConverter | JSON Object | Specifies how to extract the subject and id from message bytes. | yes |
schemaRepository | JSON Object | Specifies how to look up the Avro schema from subject and id. | yes |
Avro-1124 Subject And Id Converter
This section describes the format of the subjectAndIdConverter
object for the schema_repo
Avro bytes decoder.
Field | Type | Description | Required |
---|---|---|---|
type | String | This should say avro_1124 . |
no |
topic | String | Specifies the topic of your Kafka stream. | yes |
Avro-1124 Schema Repository
This section describes the format of the schemaRepository
object for the schema_repo
Avro bytes decoder.
Field | Type | Description | Required |
---|---|---|---|
type | String | This should say avro_1124_rest_client . |
no |
url | String | Specifies the endpoint url of your Avro-1124 schema repository. | yes |
Confluent Schema Registry-based Avro Bytes Decoder
This Avro bytes decoder first extracts a unique id
from input message bytes, and then uses it to look up the schema in the Schema Registry used to decode the Avro record from bytes.
For details, see the Schema Registry documentation and repository.
Field | Type | Description | Required |
---|---|---|---|
type | String | This should say schema_registry . |
no |
url | String | Specifies the url endpoint of the Schema Registry. | yes |
capacity | Integer | Specifies the max size of the cache (default = Integer.MAX_VALUE). | no |
...
"avroBytesDecoder" : {
"type" : "schema_registry",
"url" : <schema-registry-url>
}
...
Protobuf Parser
You need to include the
druid-protobuf-extensions
as an extension to use the Protobuf Parser.
This parser is for stream ingestion and reads Protocol buffer data from a stream directly.
Field | Type | Description | Required |
---|---|---|---|
type | String | This should say protobuf . |
yes |
descriptor | String | Protobuf descriptor file name in the classpath or URL. | yes |
protoMessageType | String | Protobuf message type in the descriptor. Both short name and fully qualified name are accepted. The parser uses the first message type found in the descriptor if not specified. | no |
parseSpec | JSON Object | Specifies the timestamp and dimensions of the data. The format must be JSON. See JSON ParseSpec for more configuration options. Note that timeAndDims parseSpec is no longer supported. | yes |
Sample spec:
"parser": {
"type": "protobuf",
"descriptor": "file:///tmp/metrics.desc",
"protoMessageType": "Metrics",
"parseSpec": {
"format": "json",
"timestampSpec": {
"column": "timestamp",
"format": "auto"
},
"dimensionsSpec": {
"dimensions": [
"unit",
"http_method",
"http_code",
"page",
"metricType",
"server"
],
"dimensionExclusions": [
"timestamp",
"value"
]
}
}
}
See the extension description for more details and examples.
ParseSpec
The Parser is deprecated for native batch tasks, Kafka indexing service, and Kinesis indexing service. Consider using the input format instead for these types of ingestion.
ParseSpecs serve two purposes:
- The String Parser use them to determine the format (i.e., JSON, CSV, TSV) of incoming rows.
- All Parsers use them to determine the timestamp and dimensions of incoming rows.
If format
is not included, the parseSpec defaults to tsv
.
JSON ParseSpec
Use this with the String Parser to load JSON.
Field | Type | Description | Required |
---|---|---|---|
format | String | This should say json . |
no |
timestampSpec | JSON Object | Specifies the column and format of the timestamp. | yes |
dimensionsSpec | JSON Object | Specifies the dimensions of the data. | yes |
flattenSpec | JSON Object | Specifies flattening configuration for nested JSON data. See flattenSpec for more info. |
no |
Sample spec:
"parseSpec": {
"format" : "json",
"timestampSpec" : {
"column" : "timestamp"
},
"dimensionSpec" : {
"dimensions" : ["page","language","user","unpatrolled","newPage","robot","anonymous","namespace","continent","country","region","city"]
}
}
JSON Lowercase ParseSpec
The jsonLowercase parser is deprecated and may be removed in a future version of Druid.
This is a special variation of the JSON ParseSpec that lower cases all the column names in the incoming JSON data. This parseSpec is required if you are updating to Druid 0.7.x from Druid 0.6.x, are directly ingesting JSON with mixed case column names, do not have any ETL in place to lower case those column names, and would like to make queries that include the data you created using 0.6.x and 0.7.x.
Field | Type | Description | Required |
---|---|---|---|
format | String | This should say jsonLowercase . |
yes |
timestampSpec | JSON Object | Specifies the column and format of the timestamp. | yes |
dimensionsSpec | JSON Object | Specifies the dimensions of the data. | yes |
CSV ParseSpec
Use this with the String Parser to load CSV. Strings are parsed using the com.opencsv library.
Field | Type | Description | Required |
---|---|---|---|
format | String | This should say csv . |
yes |
timestampSpec | JSON Object | Specifies the column and format of the timestamp. | yes |
dimensionsSpec | JSON Object | Specifies the dimensions of the data. | yes |
listDelimiter | String | A custom delimiter for multi-value dimensions. | no (default = ctrl+A) |
columns | JSON array | Specifies the columns of the data. | yes |
Sample spec:
"parseSpec": {
"format" : "csv",
"timestampSpec" : {
"column" : "timestamp"
},
"columns" : ["timestamp","page","language","user","unpatrolled","newPage","robot","anonymous","namespace","continent","country","region","city","added","deleted","delta"],
"dimensionsSpec" : {
"dimensions" : ["page","language","user","unpatrolled","newPage","robot","anonymous","namespace","continent","country","region","city"]
}
}
CSV Index Tasks
If your input files contain a header, the columns
field is optional and you don't need to set.
Instead, you can set the hasHeaderRow
field to true, which makes Druid automatically extract the column information from the header.
Otherwise, you must set the columns
field and ensure that field must match the columns of your input data in the same order.
Also, you can skip some header rows by setting skipHeaderRows
in your parseSpec. If both skipHeaderRows
and hasHeaderRow
options are set,
skipHeaderRows
is first applied. For example, if you set skipHeaderRows
to 2 and hasHeaderRow
to true, Druid will
skip the first two lines and then extract column information from the third line.
Note that hasHeaderRow
and skipHeaderRows
are effective only for non-Hadoop batch index tasks. Other types of index
tasks will fail with an exception.
Other CSV Ingestion Tasks
The columns
field must be included and and ensure that the order of the fields matches the columns of your input data in the same order.
TSV / Delimited ParseSpec
Use this with the String Parser to load any delimited text that does not require special escaping. By default, the delimiter is a tab, so this will load TSV.
Field | Type | Description | Required |
---|---|---|---|
format | String | This should say tsv . |
yes |
timestampSpec | JSON Object | Specifies the column and format of the timestamp. | yes |
dimensionsSpec | JSON Object | Specifies the dimensions of the data. | yes |
delimiter | String | A custom delimiter for data values. | no (default = \t) |
listDelimiter | String | A custom delimiter for multi-value dimensions. | no (default = ctrl+A) |
columns | JSON String array | Specifies the columns of the data. | yes |
Sample spec:
"parseSpec": {
"format" : "tsv",
"timestampSpec" : {
"column" : "timestamp"
},
"columns" : ["timestamp","page","language","user","unpatrolled","newPage","robot","anonymous","namespace","continent","country","region","city","added","deleted","delta"],
"delimiter":"|",
"dimensionsSpec" : {
"dimensions" : ["page","language","user","unpatrolled","newPage","robot","anonymous","namespace","continent","country","region","city"]
}
}
Be sure to change the delimiter
to the appropriate delimiter for your data. Like CSV, you must specify the columns and which subset of the columns you want indexed.
TSV (Delimited) Index Tasks
If your input files contain a header, the columns
field is optional and doesn't need to be set.
Instead, you can set the hasHeaderRow
field to true, which makes Druid automatically extract the column information from the header.
Otherwise, you must set the columns
field and ensure that field must match the columns of your input data in the same order.
Also, you can skip some header rows by setting skipHeaderRows
in your parseSpec. If both skipHeaderRows
and hasHeaderRow
options are set,
skipHeaderRows
is first applied. For example, if you set skipHeaderRows
to 2 and hasHeaderRow
to true, Druid will
skip the first two lines and then extract column information from the third line.
Note that hasHeaderRow
and skipHeaderRows
are effective only for non-Hadoop batch index tasks. Other types of index
tasks will fail with an exception.
Other TSV (Delimited) Ingestion Tasks
The columns
field must be included and and ensure that the order of the fields matches the columns of your input data in the same order.
Multi-value dimensions
Dimensions can have multiple values for TSV and CSV data. To specify the delimiter for a multi-value dimension, set the listDelimiter
in the parseSpec
.
JSON data can contain multi-value dimensions as well. The multiple values for a dimension must be formatted as a JSON array in the ingested data. No additional parseSpec
configuration is needed.
Regex ParseSpec
"parseSpec":{
"format" : "regex",
"timestampSpec" : {
"column" : "timestamp"
},
"dimensionsSpec" : {
"dimensions" : [<your_list_of_dimensions>]
},
"columns" : [<your_columns_here>],
"pattern" : <regex pattern for partitioning data>
}
The columns
field must match the columns of your regex matching groups in the same order. If columns are not provided, default
columns names ("column_1", "column2", ... "column_n") will be assigned. Ensure that your column names include all your dimensions.
JavaScript ParseSpec
"parseSpec":{
"format" : "javascript",
"timestampSpec" : {
"column" : "timestamp"
},
"dimensionsSpec" : {
"dimensions" : ["page","language","user","unpatrolled","newPage","robot","anonymous","namespace","continent","country","region","city"]
},
"function" : "function(str) { var parts = str.split(\"-\"); return { one: parts[0], two: parts[1] } }"
}
Note with the JavaScript parser that data must be fully parsed and returned as a {key:value}
format in the JS logic.
This means any flattening or parsing multi-dimensional values must be done here.
JavaScript-based functionality is disabled by default. Please refer to the Druid JavaScript programming guide for guidelines about using Druid's JavaScript functionality, including instructions on how to enable it.
TimeAndDims ParseSpec
Use this with non-String Parsers to provide them with timestamp and dimensions information. Non-String Parsers handle all formatting decisions on their own, without using the ParseSpec.
Field | Type | Description | Required |
---|---|---|---|
format | String | This should say timeAndDims . |
yes |
timestampSpec | JSON Object | Specifies the column and format of the timestamp. | yes |
dimensionsSpec | JSON Object | Specifies the dimensions of the data. | yes |
Orc ParseSpec
Use this with the Hadoop ORC Parser to load ORC files.
Field | Type | Description | Required |
---|---|---|---|
format | String | This should say orc . |
no |
timestampSpec | JSON Object | Specifies the column and format of the timestamp. | yes |
dimensionsSpec | JSON Object | Specifies the dimensions of the data. | yes |
flattenSpec | JSON Object | Specifies flattening configuration for nested JSON data. See flattenSpec for more info. |
no |
Parquet ParseSpec
Use this with the Hadoop Parquet Parser to load Parquet files.
Field | Type | Description | Required |
---|---|---|---|
format | String | This should say parquet . |
no |
timestampSpec | JSON Object | Specifies the column and format of the timestamp. | yes |
dimensionsSpec | JSON Object | Specifies the dimensions of the data. | yes |
flattenSpec | JSON Object | Specifies flattening configuration for nested JSON data. See flattenSpec for more info. |
no |