stream_write_csv

Write CSV Stream

Description

Writes a Spark dataframe stream into a tabular (typically, comma-separated) stream.

Usage

stream_write_csv(
  x,
  path,
  mode = c("append", "complete", "update"),
  trigger = stream_trigger_interval(),
  checkpoint = file.path(path, "checkpoint"),
  header = TRUE,
  delimiter = ",",
  quote = "\"",
  escape = "\\",
  charset = "UTF-8",
  null_value = NULL,
  options = list(),
  partition_by = NULL,
  ...
)

Arguments

Argument Description
x A Spark DataFrame or dplyr operation
path The path to the file. Needs to be accessible from the cluster. Supports the “hdfs://”, “s3a://” and “file://” protocols.
mode Specifies how data is written to a streaming sink. Valid values are "append", "complete" or "update".
trigger The trigger for the stream query, defaults to micro-batches runnnig every 5 seconds. See stream_trigger_interval and stream_trigger_continuous.
checkpoint The location where the system will write all the checkpoint information to guarantee end-to-end fault-tolerance.
header Should the first row of data be used as a header? Defaults to TRUE.
delimiter The character used to delimit each column, defaults to ,.
quote The character used as a quote. Defaults to ‘“’.
escape The character used to escape other characters, defaults to \.
charset The character set, defaults to "UTF-8".
null_value The character to use for default values, defaults to NULL.
options A list of strings with additional options.
partition_by Partitions the output by the given list of columns.
Optional arguments; currently unused.

Examples



sc <- spark_connect(master = "local")

dir.create("csv-in")
write.csv(iris, "csv-in/data.csv", row.names = FALSE)

csv_path <- file.path("file://", getwd(), "csv-in")

stream <- stream_read_csv(sc, csv_path) %>% stream_write_csv("csv-out")

stream_stop(stream)

See Also

Other Spark stream serialization: stream_read_csv(), stream_read_delta(), stream_read_json(), stream_read_kafka(), stream_read_orc(), stream_read_parquet(), stream_read_socket(), stream_read_text(), stream_write_console(), stream_write_delta(), stream_write_json(), stream_write_kafka(), stream_write_memory(), stream_write_orc(), stream_write_parquet(), stream_write_text()