AWS Glue Construct Library
---The APIs of higher level constructs in this module are experimental and under active development. They are subject to non-backward compatible changes or removal in any future version. These are not subject to the Semantic Versioning model and breaking changes will be announced in the release notes. This means that while you may use them, you may need to update your source code when upgrading to a newer version of this package.
This module is part of the AWS Cloud Development Kit project.
Job
A Job
encapsulates a script that connects to data sources, processes them, and then writes output to a data target.
There are 3 types of jobs supported by AWS Glue: Spark ETL, Spark Streaming, and Python Shell jobs.
The glue.JobExecutable
allows you to specify the type of job, the language to use and the code assets required by the job.
glue.Code
allows you to refer to the different code assets required by the job, either from an existing S3 location or from a local file path.
glue.ExecutionClass
allows you to specify FLEX
or STANDARD
. FLEX
is appropriate for non-urgent jobs such as pre-production jobs, testing, and one-time data loads.
Spark Jobs
These jobs run in an Apache Spark environment managed by AWS Glue.
ETL Jobs
An ETL job processes data in batches using Apache Spark.
# bucket: s3.Bucket
glue.Job(self, "ScalaSparkEtlJob",
executable=glue.JobExecutable.scala_etl(
glue_version=glue.GlueVersion.V4_0,
script=glue.Code.from_bucket(bucket, "src/com/example/HelloWorld.scala"),
class_name="com.example.HelloWorld",
extra_jars=[glue.Code.from_bucket(bucket, "jars/HelloWorld.jar")]
),
worker_type=glue.WorkerType.G_8X,
description="an example Scala ETL job"
)
Streaming Jobs
A Streaming job is similar to an ETL job, except that it performs ETL on data streams. It uses the Apache Spark Structured Streaming framework. Some Spark job features are not available to streaming ETL jobs.
glue.Job(self, "PythonSparkStreamingJob",
executable=glue.JobExecutable.python_streaming(
glue_version=glue.GlueVersion.V4_0,
python_version=glue.PythonVersion.THREE,
script=glue.Code.from_asset(path.join(__dirname, "job-script", "hello_world.py"))
),
description="an example Python Streaming job"
)
Python Shell Jobs
A Python shell job runs Python scripts as a shell and supports a Python version that depends on the AWS Glue version you are using. This can be used to schedule and run tasks that don’t require an Apache Spark environment. Currently, three flavors are supported:
PythonVersion.TWO (2.7; EOL)
PythonVersion.THREE (3.6)
PythonVersion.THREE_NINE (3.9)
# bucket: s3.Bucket
glue.Job(self, "PythonShellJob",
executable=glue.JobExecutable.python_shell(
glue_version=glue.GlueVersion.V1_0,
python_version=glue.PythonVersion.THREE,
script=glue.Code.from_bucket(bucket, "script.py")
),
description="an example Python Shell job"
)
Ray Jobs
These jobs run in a Ray environment managed by AWS Glue.
glue.Job(self, "RayJob",
executable=glue.JobExecutable.python_ray(
glue_version=glue.GlueVersion.V4_0,
python_version=glue.PythonVersion.THREE_NINE,
runtime=glue.Runtime.RAY_TWO_FOUR,
script=glue.Code.from_asset(path.join(__dirname, "job-script", "hello_world.py"))
),
worker_type=glue.WorkerType.Z_2X,
worker_count=2,
description="an example Ray job"
)
Enable Spark UI
Enable Spark UI setting the sparkUI
property.
glue.Job(self, "EnableSparkUI",
job_name="EtlJobWithSparkUIPrefix",
spark_uI=glue.SparkUIProps(
enabled=True
),
executable=glue.JobExecutable.python_etl(
glue_version=glue.GlueVersion.V3_0,
python_version=glue.PythonVersion.THREE,
script=glue.Code.from_asset(path.join(__dirname, "job-script", "hello_world.py"))
)
)
The sparkUI
property also allows the specification of an s3 bucket and a bucket prefix.
See documentation for more information on adding jobs in Glue.
Connection
A Connection
allows Glue jobs, crawlers and development endpoints to access certain types of data stores. For example, to create a network connection to connect to a data source within a VPC:
# security_group: ec2.SecurityGroup
# subnet: ec2.Subnet
glue.Connection(self, "MyConnection",
type=glue.ConnectionType.NETWORK,
# The security groups granting AWS Glue inbound access to the data source within the VPC
security_groups=[security_group],
# The VPC subnet which contains the data source
subnet=subnet
)
For RDS Connection
by JDBC, it is recommended to manage credentials using AWS Secrets Manager. To use Secret, specify SECRET_ID
in properties
like the following code. Note that in this case, the subnet must have a route to the AWS Secrets Manager VPC endpoint or to the AWS Secrets Manager endpoint through a NAT gateway.
# security_group: ec2.SecurityGroup
# subnet: ec2.Subnet
# db: rds.DatabaseCluster
glue.Connection(self, "RdsConnection",
type=glue.ConnectionType.JDBC,
security_groups=[security_group],
subnet=subnet,
properties={
"JDBC_CONNECTION_URL": f"jdbc:mysql://{db.clusterEndpoint.socketAddress}/databasename",
"JDBC_ENFORCE_SSL": "false",
"SECRET_ID": db.secret.secret_name
}
)
If you need to use a connection type that doesn’t exist as a static member on ConnectionType
, you can instantiate a ConnectionType
object, e.g: new glue.ConnectionType('NEW_TYPE')
.
See Adding a Connection to Your Data Store and Connection Structure documentation for more information on the supported data stores and their configurations.
SecurityConfiguration
A SecurityConfiguration
is a set of security properties that can be used by AWS Glue to encrypt data at rest.
glue.SecurityConfiguration(self, "MySecurityConfiguration",
cloud_watch_encryption=glue.CloudWatchEncryption(
mode=glue.CloudWatchEncryptionMode.KMS
),
job_bookmarks_encryption=glue.JobBookmarksEncryption(
mode=glue.JobBookmarksEncryptionMode.CLIENT_SIDE_KMS
),
s3_encryption=glue.S3Encryption(
mode=glue.S3EncryptionMode.KMS
)
)
By default, a shared KMS key is created for use with the encryption configurations that require one. You can also supply your own key for each encryption config, for example, for CloudWatch encryption:
# key: kms.Key
glue.SecurityConfiguration(self, "MySecurityConfiguration",
cloud_watch_encryption=glue.CloudWatchEncryption(
mode=glue.CloudWatchEncryptionMode.KMS,
kms_key=key
)
)
See documentation for more info for Glue encrypting data written by Crawlers, Jobs, and Development Endpoints.
Database
A Database
is a logical grouping of Tables
in the Glue Catalog.
glue.Database(self, "MyDatabase",
database_name="my_database",
description="my_database_description"
)
Table
A Glue table describes a table of data in S3: its structure (column names and types), location of data (S3 objects with a common prefix in a S3 bucket), and format for the files (Json, Avro, Parquet, etc.):
# my_database: glue.Database
glue.S3Table(self, "MyTable",
database=my_database,
columns=[glue.Column(
name="col1",
type=glue.Schema.STRING
), glue.Column(
name="col2",
type=glue.Schema.array(glue.Schema.STRING),
comment="col2 is an array of strings"
)],
data_format=glue.DataFormat.JSON
)
By default, a S3 bucket will be created to store the table’s data but you can manually pass the bucket
and s3Prefix
:
# my_bucket: s3.Bucket
# my_database: glue.Database
glue.S3Table(self, "MyTable",
bucket=my_bucket,
s3_prefix="my-table/",
# ...
database=my_database,
columns=[glue.Column(
name="col1",
type=glue.Schema.STRING
)],
data_format=glue.DataFormat.JSON
)
Glue tables can be configured to contain user-defined properties, to describe the physical storage of table data, through the storageParameters
property:
# my_database: glue.Database
glue.S3Table(self, "MyTable",
storage_parameters=[
glue.StorageParameter.skip_header_line_count(1),
glue.StorageParameter.compression_type(glue.CompressionType.GZIP),
glue.StorageParameter.custom("separatorChar", ",")
],
# ...
database=my_database,
columns=[glue.Column(
name="col1",
type=glue.Schema.STRING
)],
data_format=glue.DataFormat.JSON
)
Glue tables can also be configured to contain user-defined table properties through the parameters
property:
# my_database: glue.Database
glue.S3Table(self, "MyTable",
parameters={
"key1": "val1",
"key2": "val2"
},
database=my_database,
columns=[glue.Column(
name="col1",
type=glue.Schema.STRING
)],
data_format=glue.DataFormat.JSON
)
Partition Keys
To improve query performance, a table can specify partitionKeys
on which data is stored and queried separately. For example, you might partition a table by year
and month
to optimize queries based on a time window:
# my_database: glue.Database
glue.S3Table(self, "MyTable",
database=my_database,
columns=[glue.Column(
name="col1",
type=glue.Schema.STRING
)],
partition_keys=[glue.Column(
name="year",
type=glue.Schema.SMALL_INT
), glue.Column(
name="month",
type=glue.Schema.SMALL_INT
)],
data_format=glue.DataFormat.JSON
)
Partition Indexes
Another way to improve query performance is to specify partition indexes. If no partition indexes are present on the table, AWS Glue loads all partitions of the table and filters the loaded partitions using the query expression. The query takes more time to run as the number of partitions increase. With an index, the query will try to fetch a subset of the partitions instead of loading all partitions of the table.
The keys of a partition index must be a subset of the partition keys of the table. You can have a
maximum of 3 partition indexes per table. To specify a partition index, you can use the partitionIndexes
property:
# my_database: glue.Database
glue.S3Table(self, "MyTable",
database=my_database,
columns=[glue.Column(
name="col1",
type=glue.Schema.STRING
)],
partition_keys=[glue.Column(
name="year",
type=glue.Schema.SMALL_INT
), glue.Column(
name="month",
type=glue.Schema.SMALL_INT
)],
partition_indexes=[glue.PartitionIndex(
index_name="my-index", # optional
key_names=["year"]
)], # supply up to 3 indexes
data_format=glue.DataFormat.JSON
)
Alternatively, you can call the addPartitionIndex()
function on a table:
# my_table: glue.Table
my_table.add_partition_index(
index_name="my-index",
key_names=["year"]
)
Partition Filtering
If you have a table with a large number of partitions that grows over time, consider using AWS Glue partition indexing and filtering.
# my_database: glue.Database
glue.S3Table(self, "MyTable",
database=my_database,
columns=[glue.Column(
name="col1",
type=glue.Schema.STRING
)],
partition_keys=[glue.Column(
name="year",
type=glue.Schema.SMALL_INT
), glue.Column(
name="month",
type=glue.Schema.SMALL_INT
)],
data_format=glue.DataFormat.JSON,
enable_partition_filtering=True
)
Glue Connections
Glue connections allow external data connections to third party databases and data warehouses. However, these connections can also be assigned to Glue Tables, allowing you to query external data sources using the Glue Data Catalog.
Whereas S3Table
will point to (and if needed, create) a bucket to store the tables’ data, ExternalTable
will point to an existing table in a data source. For example, to create a table in Glue that points to a table in Redshift:
# my_connection: glue.Connection
# my_database: glue.Database
glue.ExternalTable(self, "MyTable",
connection=my_connection,
external_data_location="default_db_public_example", # A table in Redshift
# ...
database=my_database,
columns=[glue.Column(
name="col1",
type=glue.Schema.STRING
)],
data_format=glue.DataFormat.JSON
)
Encryption
You can enable encryption on a Table’s data:
S3Managed - (default) Server side encryption (
SSE-S3
) with an Amazon S3-managed key.
# my_database: glue.Database
glue.S3Table(self, "MyTable",
encryption=glue.TableEncryption.S3_MANAGED,
# ...
database=my_database,
columns=[glue.Column(
name="col1",
type=glue.Schema.STRING
)],
data_format=glue.DataFormat.JSON
)
Kms - Server-side encryption (
SSE-KMS
) with an AWS KMS Key managed by the account owner.
# my_database: glue.Database
# KMS key is created automatically
glue.S3Table(self, "MyTable",
encryption=glue.TableEncryption.KMS,
# ...
database=my_database,
columns=[glue.Column(
name="col1",
type=glue.Schema.STRING
)],
data_format=glue.DataFormat.JSON
)
# with an explicit KMS key
glue.S3Table(self, "MyTable",
encryption=glue.TableEncryption.KMS,
encryption_key=kms.Key(self, "MyKey"),
# ...
database=my_database,
columns=[glue.Column(
name="col1",
type=glue.Schema.STRING
)],
data_format=glue.DataFormat.JSON
)
KmsManaged - Server-side encryption (
SSE-KMS
), likeKms
, except with an AWS KMS Key managed by the AWS Key Management Service.
# my_database: glue.Database
glue.S3Table(self, "MyTable",
encryption=glue.TableEncryption.KMS_MANAGED,
# ...
database=my_database,
columns=[glue.Column(
name="col1",
type=glue.Schema.STRING
)],
data_format=glue.DataFormat.JSON
)
ClientSideKms - Client-side encryption (
CSE-KMS
) with an AWS KMS Key managed by the account owner.
# my_database: glue.Database
# KMS key is created automatically
glue.S3Table(self, "MyTable",
encryption=glue.TableEncryption.CLIENT_SIDE_KMS,
# ...
database=my_database,
columns=[glue.Column(
name="col1",
type=glue.Schema.STRING
)],
data_format=glue.DataFormat.JSON
)
# with an explicit KMS key
glue.S3Table(self, "MyTable",
encryption=glue.TableEncryption.CLIENT_SIDE_KMS,
encryption_key=kms.Key(self, "MyKey"),
# ...
database=my_database,
columns=[glue.Column(
name="col1",
type=glue.Schema.STRING
)],
data_format=glue.DataFormat.JSON
)
Note: you cannot provide a Bucket
when creating the S3Table
if you wish to use server-side encryption (KMS
, KMS_MANAGED
or S3_MANAGED
).
Types
A table’s schema is a collection of columns, each of which have a name
and a type
. Types are recursive structures, consisting of primitive and complex types:
# my_database: glue.Database
glue.S3Table(self, "MyTable",
columns=[glue.Column(
name="primitive_column",
type=glue.Schema.STRING
), glue.Column(
name="array_column",
type=glue.Schema.array(glue.Schema.INTEGER),
comment="array<integer>"
), glue.Column(
name="map_column",
type=glue.Schema.map(glue.Schema.STRING, glue.Schema.TIMESTAMP),
comment="map<string,string>"
), glue.Column(
name="struct_column",
type=glue.Schema.struct([
name="nested_column",
type=glue.Schema.DATE,
comment="nested comment"
]),
comment="struct<nested_column:date COMMENT 'nested comment'>"
)],
# ...
database=my_database,
data_format=glue.DataFormat.JSON
)
Primitives
Numeric
| Name | Type | Comments | |———– |———- |—————————————————————————————————————— | | FLOAT | Constant | A 32-bit single-precision floating point number | | INTEGER | Constant | A 32-bit signed value in two’s complement format, with a minimum value of -2^31 and a maximum value of 2^31-1 | | DOUBLE | Constant | A 64-bit double-precision floating point number | | BIG_INT | Constant | A 64-bit signed INTEGER in two’s complement format, with a minimum value of -2^63 and a maximum value of 2^63 -1 | | SMALL_INT | Constant | A 16-bit signed INTEGER in two’s complement format, with a minimum value of -2^15 and a maximum value of 2^15-1 | | TINY_INT | Constant | A 8-bit signed INTEGER in two’s complement format, with a minimum value of -2^7 and a maximum value of 2^7-1 |
Date and time
| Name | Type | Comments | |———– |———- |————————————————————————————————————————————————————————- | | DATE | Constant | A date in UNIX format, such as YYYY-MM-DD. | | TIMESTAMP | Constant | Date and time instant in the UNiX format, such as yyyy-mm-dd hh:mm:ss[.f…]. For example, TIMESTAMP ‘2008-09-15 03:04:05.324’. This format uses the session time zone. |
String
| Name | Type | Comments |
|——————————————– |———- |————————————————————————————————————————————————————————————————— |
| STRING | Constant | A string literal enclosed in single or double quotes |
| decimal(precision: number, scale?: number) | Function | precision
is the total number of digits. scale
(optional) is the number of digits in fractional part with a default of 0. For example, use these type definitions: decimal(11,5), decimal(15) |
| char(length: number) | Function | Fixed length character data, with a specified length between 1 and 255, such as char(10) |
| varchar(length: number) | Function | Variable length character data, with a specified length between 1 and 65535, such as varchar(10) |
Miscellaneous
| Name | Type | Comments |
|——— |———- |——————————- |
| BOOLEAN | Constant | Values are true
and false
|
| BINARY | Constant | Value is in binary |
Complex
| Name | Type | Comments | |————————————- |———- |——————————————————————- | | array(itemType: Type) | Function | An array of some other type | | map(keyType: Type, valueType: Type) | Function | A map of some primitive key type to any value type | | struct(collumns: Column[]) | Function | Nested structure containing individually named and typed collumns |
Data Quality Ruleset
A DataQualityRuleset
specifies a data quality ruleset with DQDL rules applied to a specified AWS Glue table. For example, to create a data quality ruleset for a given table:
glue.DataQualityRuleset(self, "MyDataQualityRuleset",
client_token="client_token",
description="description",
ruleset_name="ruleset_name",
ruleset_dqdl="ruleset_dqdl",
tags={
"key1": "value1",
"key2": "value2"
},
target_table=glue.DataQualityTargetTable("database_name", "table_name")
)
For more information, see AWS Glue Data Quality.