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author | Felix Cheung <felixcheung_m@hotmail.com> | 2016-06-17 21:36:01 -0700 |
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committer | Shivaram Venkataraman <shivaram@cs.berkeley.edu> | 2016-06-17 21:36:01 -0700 |
commit | 8c198e246d64b5779dc3a2625d06ec958553a20b (patch) | |
tree | 8e882c1a467cb454863b08c74124a36d30120314 /R/pkg/inst/profile | |
parent | edb23f9e47eecfe60992dde0e037ec1985c77e1d (diff) | |
download | spark-8c198e246d64b5779dc3a2625d06ec958553a20b.tar.gz spark-8c198e246d64b5779dc3a2625d06ec958553a20b.tar.bz2 spark-8c198e246d64b5779dc3a2625d06ec958553a20b.zip |
[SPARK-15159][SPARKR] SparkR SparkSession API
## What changes were proposed in this pull request?
This PR introduces the new SparkSession API for SparkR.
`sparkR.session.getOrCreate()` and `sparkR.session.stop()`
"getOrCreate" is a bit unusual in R but it's important to name this clearly.
SparkR implementation should
- SparkSession is the main entrypoint (vs SparkContext; due to limited functionality supported with SparkContext in SparkR)
- SparkSession replaces SQLContext and HiveContext (both a wrapper around SparkSession, and because of API changes, supporting all 3 would be a lot more work)
- Changes to SparkSession is mostly transparent to users due to SPARK-10903
- Full backward compatibility is expected - users should be able to initialize everything just in Spark 1.6.1 (`sparkR.init()`), but with deprecation warning
- Mostly cosmetic changes to parameter list - users should be able to move to `sparkR.session.getOrCreate()` easily
- An advanced syntax with named parameters (aka varargs aka "...") is supported; that should be closer to the Builder syntax that is in Scala/Python (which unfortunately does not work in R because it will look like this: `enableHiveSupport(config(config(master(appName(builder(), "foo"), "local"), "first", "value"), "next, "value"))`
- Updating config on an existing SparkSession is supported, the behavior is the same as Python, in which config is applied to both SparkContext and SparkSession
- Some SparkSession changes are not matched in SparkR, mostly because it would be breaking API change: `catalog` object, `createOrReplaceTempView`
- Other SQLContext workarounds are replicated in SparkR, eg. `tables`, `tableNames`
- `sparkR` shell is updated to use the SparkSession entrypoint (`sqlContext` is removed, just like with Scale/Python)
- All tests are updated to use the SparkSession entrypoint
- A bug in `read.jdbc` is fixed
TODO
- [x] Add more tests
- [ ] Separate PR - update all roxygen2 doc coding example
- [ ] Separate PR - update SparkR programming guide
## How was this patch tested?
unit tests, manual tests
shivaram sun-rui rxin
Author: Felix Cheung <felixcheung_m@hotmail.com>
Author: felixcheung <felixcheung_m@hotmail.com>
Closes #13635 from felixcheung/rsparksession.
Diffstat (limited to 'R/pkg/inst/profile')
-rw-r--r-- | R/pkg/inst/profile/shell.R | 12 |
1 files changed, 6 insertions, 6 deletions
diff --git a/R/pkg/inst/profile/shell.R b/R/pkg/inst/profile/shell.R index 90a3761e41..8a8111a8c5 100644 --- a/R/pkg/inst/profile/shell.R +++ b/R/pkg/inst/profile/shell.R @@ -18,17 +18,17 @@ .First <- function() { home <- Sys.getenv("SPARK_HOME") .libPaths(c(file.path(home, "R", "lib"), .libPaths())) - Sys.setenv(NOAWT=1) + Sys.setenv(NOAWT = 1) # Make sure SparkR package is the last loaded one old <- getOption("defaultPackages") options(defaultPackages = c(old, "SparkR")) - sc <- SparkR::sparkR.init() - assign("sc", sc, envir=.GlobalEnv) - sqlContext <- SparkR::sparkRSQL.init(sc) + spark <- SparkR::sparkR.session() + assign("spark", spark, envir = .GlobalEnv) + sc <- SparkR:::callJStatic("org.apache.spark.sql.api.r.SQLUtils", "getJavaSparkContext", spark) + assign("sc", sc, envir = .GlobalEnv) sparkVer <- SparkR:::callJMethod(sc, "version") - assign("sqlContext", sqlContext, envir=.GlobalEnv) cat("\n Welcome to") cat("\n") cat(" ____ __", "\n") @@ -43,5 +43,5 @@ cat(" /_/", "\n") cat("\n") - cat("\n Spark context is available as sc, SQL context is available as sqlContext\n") + cat("\n SparkSession available as 'spark'.\n") } |