library(sparklyr)
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) Write CSV Stream
R/stream_data.R
stream_write_csv
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
| Arguments | 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
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()