Create spark dataframe schema from json schema representation

Question

Is there a way to serialize a dataframe schema to json and deserialize it later on?

The use case is simple: I have a json configuration file which contains the sche

Answer 1

I am posting a pyspark version to a question answered by Assaf:

from pyspark.sql.types import StructType    

# Save schema from the original DataFrame into json:
schema_json = df.schema.json()

# Restore schema from json:
import json
new_schema = StructType.fromJson(json.loads(schema_json))

Answer 2

There are two steps for this: Creating the json from an existing dataframe and creating the schema from the previously saved json string.

Creating the string from an existing dataframe

    val schema = df.schema
    val jsonString = schema.json

create a schema from json

    import org.apache.spark.sql.types.{DataType, StructType}
    val newSchema = DataType.fromJson(jsonString).asInstanceOf[StructType]