Contoh skrip visual kustom - AWS Glue

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Contoh skrip visual kustom

Contoh-contoh berikut melakukan transformasi yang setara. Namun, contoh kedua (SparkSQL) adalah yang terbersih dan paling efisien, diikuti oleh Pandas UDF dan akhirnya pemetaan tingkat rendah pada contoh pertama. Contoh berikut adalah contoh lengkap dari transformasi sederhana untuk menambahkan dua kolom:

from awsglue import DynamicFrame # You can have other auxiliary variables, functions or classes on this file, it won't affect the runtime def record_sum(rec, col1, col2, resultCol): rec[resultCol] = rec[col1] + rec[col2] return rec # The number and name of arguments must match the definition on json config file # (expect self which is the current DynamicFrame to transform # If an argument is optional, you need to define a default value here # (resultCol in this example is an optional argument) def custom_add_columns(self, col1, col2, resultCol="result"): # The mapping will alter the columns order, which could be important fields = [field.name for field in self.schema()] if resultCol not in fields: # If it's a new column put it at the end fields.append(resultCol) return self.map(lambda record: record_sum(record, col1, col2, resultCol)).select_fields(paths=fields) # The name we assign on DynamicFrame must match the configured "functionName" DynamicFrame.custom_add_columns = custom_add_columns

Contoh berikut adalah transformasi setara yang memanfaatkan SparkSQL API.

from awsglue import DynamicFrame # The number and name of arguments must match the definition on json config file # (expect self which is the current DynamicFrame to transform # If an argument is optional, you need to define a default value here # (resultCol in this example is an optional argument) def custom_add_columns(self, col1, col2, resultCol="result"): df = self.toDF() return DynamicFrame.fromDF( df.withColumn(resultCol, df[col1] + df[col2]) # This is the conversion logic , self.glue_ctx, self.name) # The name we assign on DynamicFrame must match the configured "functionName" DynamicFrame.custom_add_columns = custom_add_columns

Contoh berikut menggunakan transformasi yang sama tetapi menggunakan panda UDF, yang lebih efisien daripada menggunakan UDF biasa. Untuk informasi selengkapnya tentang menulis panda UDF lihat: Dokumentasi Apache Spark SQL.

from awsglue import DynamicFrame import pandas as pd from pyspark.sql.functions import pandas_udf # The number and name of arguments must match the definition on json config file # (expect self which is the current DynamicFrame to transform # If an argument is optional, you need to define a default value here # (resultCol in this example is an optional argument) def custom_add_columns(self, col1, col2, resultCol="result"): @pandas_udf("integer") # We need to declare the type of the result column def add_columns(value1: pd.Series, value2: pd.Series) → pd.Series: return value1 + value2 df = self.toDF() return DynamicFrame.fromDF( df.withColumn(resultCol, add_columns(col1, col2)) # This is the conversion logic , self.glue_ctx, self.name) # The name we assign on DynamicFrame must match the configured "functionName" DynamicFrame.custom_add_columns = custom_add_columns