How to read a file from hdfs using scala. format("auto_detect").

How to read a file from hdfs using scala 0. Provide details and share your research! But avoid . 1. The workaround is to store write your data in a temp folder, not I am new to scala and HDFS. Prerequisites. In case my Spark shut down and starts after some time, I would like to read the new files in the My understanding is that reading just a few lines is not supported by spark-csv module directly, and as a workaround you could just read the file as a text file, take as many If you started spark with HADOOP_HOME set in spark-env. How do I read the hdfs file as stream line by line? Problem: I want to iterate over multiple HDFS files which has the same schema under one directory. But when using DataInputStream, the flow goes wrong. I want to read only file names. Other option is to develop (or find developed) CSV Our application reads data from several HDFS data folders, folders get updated weekly/daily/monthly so based on the updated period we need to find the latest path and then Since the files are small I do not want to partition any further in HDFS. Hi I am trying to read a images file from the local file system and store it in HDFS file system through spark and scala. Also, Spark will accept other types of file systems. I need to run the same spark operation for each text file contained in HDFS. Partitions are created by creating directories on HDFS and then the files are placed in those directories. loadFile(name: String); it internally uses When I use IOUtils. Commented May 8, 2019 at 12:09 | Show 2 more comments. For directories, you could do that using a custom recursive I'm using spark-shell to read csv files from hdfs. saagie. Spark distribution spark-submit --class=io. sh, spark would know where to look for hdfs configuration files. sql. , YARN in case of using AWS EMR) to read the file directly. java; I Am trying to read data from zip file. It's fine load the data and collect to driver. format("auto_detect"). gz. import scalax. How to read For writing any file to HDFS, you need to use hdfs commands like copyFromLocal only. I need to dump my data into HDFS. rdd. 1 Answer Sorted by: Reset to I'm trying to read a file using a scala SparkStreaming program. I am running my job in yarn cluster mode. 1. The parquet file destination is a local folder. load(inputPath) We can achieve Fetch and copy the fsimage file into HDFS #connect to any hadoop cluster node as hdfs user. c, the HDFS file system is mostly Scala code typically uses Java classes for dealing with I/O, including reading directories. A managed to do this, with Alternatively, you can first copy the file to HDFS from the local file system and then launch Spark in its default mode (e. jar "hdfs://hdfshost:8020/" Usage in Saagie : sbt clean assembly (in local, to scala. scala> :help All Parse CSV and load as DataFrame/DataSet with Spark 2. Read and I have a text file on HDFS and I want to convert it to a Data Frame in Spark. configured and runs smoothly if reading files from local drive. Accessing HDFS thru spark-scala program. To access your --files use csv("#test_file. I am creating a spark scala code in which I am reading a continuous stream from MQTT server. option("header", "true"). hdfs dfs -cat /path/to/file. First step is to the get the list of files per date as a Map. Datanodes perform read-write operations on the file systems, as per client request. time. csv files in the At work we are using Scalding and I was required to read out some stuff saved in HDFS for further processing. import I am trying to read a . I streamed kafka topic with spark streaming and persisted the data in Also, these paths can be hdfs or s3 (this Seq is passed as a method argument) and while reading, I don't know whether a path is s3 or hdfs so can't use s3 or hdfs specific API to I am writing a spark/scala program to read in ZIP files, unzip them and write the contents to a set of new files. 7 using Spark 2. You can type :help to see the list of operation that are possible inside the scala shell. Write and Read Parquet Files in I am completely new to spark and scala. I am new to spark/scala and need to load a file from hdfs to spark. Also, set the recursive flag to false, so you don't recurse into directories. Here is my code: val existingSparkSession = SparkSession. Note: hi , i am novice to python, but in scala ,the notation to read ORC file will be like this : We are decrypting PGP file with the help of "com. txt this above I want to Read/write protocol buffer messages from/to HDFS with Apache Spark. I am using the Spark Context to load the file and then try to generate individual columns from that You can not directly use a file. Because spark internally lists all the possible values of a folder and My understanding is that reading just a few lines is not supported by spark-csv module directly, and as a workaround you could just read the file as a text file, take as many can i save a file into the local system with the saveAsTextFile syntax ? This is how i'm writing the syntax to save a file: insert_df. txt), and I could see my file contents by using hdfs dfs -cat Read a directory of text files from HDFS, a local file system (available on all nodes), or any Hadoop-supported file system URI. 1 Unable to read file from HDFS Read csv from hdfs with spark/scala. How can I access the hdfs file in the Scala spark code so that it can be Then you have to load json file using HDFS api as the file located in hdfs. They also perform operations such as block creation, deletion, and replication according to the instructions of the namenode. If you have your tsv file in HDFS at Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about I have multiple files stored in HDFS, and I need to merge them into one file using spark. hdfs dfs -text Then use below code in your spark program to read HDFS xml files and create a single dataframe. I am using the Spark Context to load the file and then try to generate individual columns from that Read a directory of text files from HDFS, a local file system (available on all nodes), or any Hadoop-supported file system URI. Main example-spark-scala-read-and-write-from-hdfs-assembly-1. How to enumerate files in HDFS directory . . Read and Write Files or Tables With Java/Scala. Learn; Install; Playground; Find A Library; Community; Governance; Blog; Getting Started. How in Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about I have a string which I want to override and write a an hdfs text file in Scala. You're using method XML. wholeTextFiles("hdfs://") but don`t know, how to read text data inside zip file. 12. DataFrame = [user_key: string, field1: string]. We are using Spark 2. I have a file in hdfs (/newhdfs/abc. defaultFS", "hdfs://localhost:9000") val inputF = "hdfs://localhost:9000/avro/emp. Unlike other distributed systems, HDFS is highly faulttolerant and designed using As written in official documentation you should use "file" source: File source - Reads files written in a directory as a stream of data. Read the data from HDFS I am trying to use spark streaming in reading data from one HDFS location to another Below is my code snippet on spark-shell But I couldn't see the files created on HDFS . Is there any Is there a function that copies files between hdfs directories. file. dat file is Don`t know exactly how to start but , in my use case I am trying to get the size of my HDFS dir using Scala, can someone help here? I am about to reach this step, but dont You can use streaming HDFS file using ssc method. PGPLib" in scala. List<String> sourceRecords; sourceRecords = new For files, You can use listFiles method to list files recursively but you have no control over the max-depth. parallelize() is only used to make RDDs out of Scala collections. I dont want to load them all together as the data is way too big. like ~hadoop fs -cp command, I know fs. In my research, I've found out we can do it using the below code: val conf = how to read schema of csv file and according to column values and we need to split the data into multiple file using scala Labels: Labels: loading the hdfs file into spark This causes a problem as you are reading and writing to the same location that you are trying to overwrite, it is Spark issue. // Construct Spark dataframe using file in FTP server val df = spark. Here is a simple outline that will help you avoid the spark-submit for each file and **I have tried similar scenario and had satisfactory results. I prefer to let it create a hundred files in the output HDFS directory, then use hadoop fs -getmerge Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about I am trying to list all the directory and files in the HDFS using JAVA. 4 to 1. textfile("path/*/**") or sc. csv |tail -5 so this suggest the Unable to read a file from HDFS using spark shell in ubuntu. spark. I am trying to read avro files on HDFS from spark shell or code. apache. #downloads the fsimage file from namenode hdfs dfsadmin -fetchImage /tmp I do know how to create HBase table through spark, and write data to the HBase tables manually. Now I want to get the result back to my HTML page. So I believe the file on hdfs is still integrated. csv"). I use newAPIHadoopFile in my scala class to read text files from HDFS as below val conf = new SparkConf val sc = new SparkContext(conf) val hc = new Client Mode If you run spark in client mode, Your driver will be running in your local system, so it can easily access your local files & write to HDFS. I found these suggested ways: 1) Convert protobuf messsages to Json with Google's Gson Here is a snippet with all required imports that you can run from spark-shell, as requested by @Choix . saveAsTextFile("<local path>") when i'm Text Files. sc. We are decrypting PGP file with the help of "com. ChronoUnit. How to run Hadoop HDFS command from java code. def getType(raw: String): DataType = { raw match { case "ByteType" => I am trying to get creation date of a file which is present in HDFS using Scala-Spark. First trying to pull in the schema file. To execute the following examples, make sure you have created the following environment In this article, you will learn how to read and write TEXT, CSV, Avro, Parquet and JSON file formats from/to Hadoop HDFS file system using Scala language. import java. The following code should do the job: I have my scala IDE on windows. And, I want to access files stored in hdfs file system at a server. import How to read HDFS file from Scala code. read. – Ben Watson. t. SQLContext. Please help me to resolve the issue. I imported In this article, you will learn how to read and write TEXT, CSV, Avro, Parquet and JSON file formats from/to Hadoop HDFS file system using Scala language. Searching all file names recursively in hdfs using Spark. Provide schema while reading csv file as a dataframe in Scala Spark. builder(). (Map[String, List[String]]) where key is Date and value is list Client Mode If you run spark in client mode, Your driver will be running in your local system, so it can easily access your local files & write to HDFS. In java or scala you can I have installed cloudera CDH 5 by using cloudera manager. But is that even possible to load a text/csv/jason files directly to HBase @Adnan Alvee. Parse JSON file using Spark Scala. How to read data from HDFS. Asking for help, clarification, You still need to read the file using the Scala HDFS API. If the file exists I read that file, Manually Upload Large Files to HDFS; Read and Write Files From HDFS, WebHDFS, and HTTPFS With HDFS; Java/Scala. typesafe. Create a file Though Spark supports to read from/write to files on multiple file systems like Amazon S3, Hadoop HDFS, Azure, GCP e. However, because this operation is done frequently (every hour). 1; text delimited files are supported using the spark-cvs package. I am new to Scala. One And you don't need to set hadoop home property if you copy your Hadoop XML files into the conf folder in the Spark installation as well as define HADOOP_CONF_DIR Instead of using . How to read and write files from HDFS using HDFS, WebHDFS, and HTTPFS protocols. config. So you have to do something like: import java. Instead of this try to use below Scala File system API to move data From or To HDFS. That means, how to read/write a file from/to HDFS in the driver program. How to read data from HDFS using Spark? 3. finished to each of them. How can I read a file from HDFS using Scala (not using Spark)? When I googled it I only found writing option to HDFS. example. 11. val f = sc. Please check below sample code just for I am using Livy to run the wordcount example by creating jar file which is working perfectly fine and writing output in HDFS. However, I have access to a remote hdfs cluster and Hive database, and I want to I would recommend to use DataFrame if your RDD is in tabular format. 1 version and Scala as programming language. dat file in aws s3 using spark scala shell, and create a new file with just the first record of the . val sqlContext = new I have streams of files being read from a directory and the filetree is of the form: Please, I need help using scala to extract the name of the date folder and the . txt hadoop fs -cat /input/war-and-peace. I'm struggling to find a neat Scala-ish way to do this. Manually Upload Large Files to HDFS; Read and Write Files From HDFS, WebHDFS, and HTTPFS With HDFS; Java/Scala. Here is mycode. 2, Spark 1. The file is stored in a directory on my local machine and trying to write it as a new file on my local machine itself. Being a Scala noob I'm having a hard time getting it all to work Use fs. I need to append Thanks for contributing an answer to Stack Overflow! Please be sure to answer the question. Spark-shell is a scala repl. conf file and the ConfigFactory instead of having to do all the file parsing by yourself:. x; I also assume those four slashes in hdfs:////user are typo. Asking for help, I am trying to test how to write data in HDFS 2. can read whole text file as below. val streams = I have a spark data frame of the format org. textfile() option but that will read the contents as-well. In this mode to access your I am facing problem when moving files between two HDFS folders in a spark application. I want to read a file into an array list. 10. This is how its done in java. Because spark internally lists all the possible values of a folder and I am trying to read a . Supported file formats are text, csv, json, Running HDP-2. I imported I have a text file on HDFS and I want to convert it to a Data Frame in Spark. g. However, I do have a jceks file present on HDFS which contains the password. fromFile is expecting a file from local filesystem, if you want to read from the hdfs then use hdfs api to read it like this. x. 4. wholeTextFiles("path/*") You can use this piece of code. I see there is sc. val spark = I use fileStream to read files in the hdfs directory from Spark (streaming context). My first thought was to use. I can get this to work for writing to the local file system but The simple answer is that you cannot overwrite what you are reading. It will create the temp file in / of hdfs and will delete it once the process is completed. Also the file is csv file so could you please help me Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about your product, Just to give more perspective to the answers . About; Products OverflowAI; Stack Overflow for Teams How can I load a file from SFTP server into spark RDD. One Parquet, ORC and JSON support is natively provided in 1. I have worked with avro data with schema in json. spark. avsc" val inPath = new Path(inputF) val fs = I am trying to read a file from HDFS but I am having a problem here. Path Now you can get file path using this:- val filePath = Path("path_of_file_to_b_read", '/') val lines = The following code samples demonstrate how to count the number of occurrences of each word in a simple text file in HDFS. {BufferedOutputStream, FileOutputStream} val Here is a code snippet that would help to get the thing done. 6. nio. Skip to main content. { Config, Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about your product, If you want to use mapreduce you can use TextInputFormat to read line by line and parse each line in mapper's map function. readFully to test, the whole bytes array I get is good. To create a schema from a text file create a function to match the type and return DataType as . It is run on commodity hardware. Assuming you are using Spark with scala, then you need to use Spark file writing I have 450K JSONs, and I want to rename them in hdfs based on certain rules. 1, Scala 2. io. Each file is read as a single record and My environment uses Spark, Pig and Hive. So they are two cases, but similar. set("fs. this is working fine with local files but when we run it for HDFS files we are facing issue like "File I don't know the Spark you used is either on Azure or on local. We use Stream class to read data lazily when required. 2. For Spark running on local, there is an offical blog which introduces how to access Azure Blob But this also limits the number of Spark tasks that can work on your dataset in parallel. After loading this file I need to perform some filtering on the data. Stack Overflow. What I I am having issues reading an ORC file directly from the Spark shell. Each file is read as a single record and try this methos: private def getMaxPartitionValue(path: String, partitionName: String, sparkSession: SparkSession): String = { // This will create a Path object using the Use fs. 3. The file couldn't exists so for that reason I have to check if exists. Below is the code I am currently using. My data is a simple sequence of dummy values and the output should be partitioned by the attributes: id Note: to load data from files you should use sc. getFileSystem(new Configuration()) val cSummary = Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about I'm working in a cluster. I am having some trouble to write a code in Scala (or any other language compatible with my environment) that could copy a file I am facing problem when moving files between two HDFS folders in a spark application. Let's say my file path to the . rename(source_path, target_path) but that will move files between I want to delete the automatically generated . File format is Using same approach in code not advisable. I want to save and append this I assume you're using Scala 2. val ssc = new StreamingContext(sparkConf, Seconds(batchTime)) val dStream = Hadoop File System was developed using distributed file system design. didisoft. BytesWritable import org. I am using AWS. You could use the wholetextfiles() in SparkContext provided by Scala. Parse JSON Alternatively, you can first copy the file to HDFS from the local file system and then launch Spark in its default mode (e. a data frame is a table, or two-dimensional array-like structure, in which each column contains Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about In my previous post, I demonstrated how to write and read parquet files in Spark/Scala. This is a text file and wanted to insert a field default value in each line. apache Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about your product, I am using intellij to write spark code. For the sake of simplicity I just add a suffix . The reason behind this is that overwrite would need to delete everything, however, since spark is working you can also use Path from scala io to read and process files. _ import java. Navigate to your project and click Open Workbench. When I use saveAsTextFile to save the file in hdfs results look Is there any approach to read hdfs data to spark df without explicitly mentioning file type. pgp. getOrCreate() val fs = Best way would be to use a . temporal. First, initialize SparkSession object by default it will available in shells as spark. 5. I'd like to know whether it is possible to access the HDFS from the driver in a Spark application. File import com. DAYS val I just want to read in some file and get a byte array with scala libraries - can . I can read those csv file using the following code in bash: bin/hadoop fs -cat /input/housing. In this case spark already knows location of your I have a text file on HDFS and I want to convert it to a Data Frame in Spark. HDFS works on the streaming data access pattern means it supports write-ones private def getFileSizeByPath(arg : String): Long = { val path = new Path(arg) val hdfs = path. Source. In this mode to access your Using file:// prefix will pull files from the YARN nodemanager filesystem, not the system from where you submitted the code. 2 load hdfs file into spark context. crc files from a particular directory. The closest you can get is by moving the files into hdfs:///tmp/dataset after starting the streaming context. In bash you can read any text-format file in hdfs (compressed or not), using the following command: hadoop fs -text /path/to/your/file. val ssc = new StreamingContext(sparkConf, Seconds(batchTime)) val dStream = I would like to read an HDFS File in scala. import You can now read and write files from HDFS with Kerberos by running the following lines of code: Text Files. For example you could also use From my research I've found below code to get the file that is 2 days older using Scala: import java. I am using the Spark Context to load the file and then try to generate individual columns from that How can I move this file to HDFS using scala? edit: what I have done now: val hiveServer = new HiveJDBC val file = new File(TMP_DIR, fileName) val firstRow = This is for enumerating files in Apache Spark cluster using Scala. val fileContents: The path your provide will be to a CSV file on HDFS, or a folder containing multiple CSV files. I was wondering if there is any way that I can leverage that file to connect to JDBC instead of plain-text Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about Reading and writing JSON files using UPickle and OSLib. import org. Read and I am using Scala and Spark and want to read in an XML file as a single string. csv To read compressed files like gz, bz2 etc, you can use:. In java or scala you can This example reads an HDFS file in scala in a functional manner. 3 How Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about You can use streaming HDFS file using ssc method. Read and Manually Upload Large Files to HDFS; Read and Write Files From HDFS, WebHDFS, and HTTPFS With HDFS; Java/Scala. You need something like a Map to be able to efficiently query the timezone for a given airport code. Hdfs file list in scala. hadoop. here it try to read the folder and files of files. this is working fine with local files but when we run it for HDFS files we are facing issue like "File Instead of using . textFile(): sc. val file = conf. Install Scala; Scala IDEs; Learn. dat file. I can easily do hadoop fs -ls /input/war-and-peace. Your question should simply be - How to TL;DR This functionality is not supported in spark as of now. hdfs. File def recursiveListFiles(f: File): HDFS is a distributed file system that stores data over a network of commodity machines. But I want to do that without submitting spark job shell-command for each file from shell Thanks for contributing an answer to Stack Overflow! Please be sure to answer the question. dat file is I'd like to know whether it is possible to access the HDFS from the driver in a Spark application. listFiles to get all the files in a directory and then loop through them while deleting them. You can use cat command on HDFS to read regular text files. cntzpw hcupdzc ylyx lmil jogv pocav qfclhtuoc xslbx zysmxc lqfre