# Process several CSV lines at the same time with a feed **URL:** \ **Category:** Gatling (Open-Source)\ **Created:** [January 11, 2013, 9:06am UTC](https://community.gatling.io/t/process-several-csv-lines-at-the-same-time-with-a-feed/223 "2013-01-11T09:06:36Z")\ **Posts on this page:** 14\ **Page:** 1
**Author:** ![Loic\_Descotte](https://avatars.discourse-cdn.com/v4/letter/l/8e7dd6/32.png) [@Loic\_Descotte](https://community.gatling.io/u/Loic_Descotte)\ **Post date:** [January 11, 2013, 9:06am UTC](https://community.gatling.io/t/process-several-csv-lines-at-the-same-time-with-a-feed/223/1 "2013-01-11T09:06:36Z")
Hi, is it possible to process several CSV lines at the same time with a feed? e.g I need to create an xml file from a template to send it via HTTP POST. For each request my XML must contain data from 5 lines in my CSV data file. Currently I do : feed(csv(dataSource).circular) .exec( http(“myRequest”) .post(URI) //loading template from ssp file .fileBody(“myRequest”, Map( “name” → “${name}”, “address” → “${address}” )).asXML .headers(commonHeaders) .check(status.is(200)) ) } When I do this I can process only 1 line of the CSV and my XML looks like : $name $address How can I do if I want something like this, reading CSV entries 5 by 5? $name1 $address1 $name2 $address2 .. .. .. .. .. .. Thanks Loic ---
**Author:** ![Excilys](https://avatars.discourse-cdn.com/v4/letter/e/8797f3/32.png) [@Excilys](https://community.gatling.io/u/Excilys)\ **Post date:** [January 11, 2013, 10:09am UTC](https://community.gatling.io/t/process-several-csv-lines-at-the-same-time-with-a-feed/223/2 "2013-01-11T10:09:33Z")
Hi Loïc, Your problem is a bit more complex than just polling 5 by 5 as you want the attributes names not to clash. Feeder is an alias for Iterator[Map[String, \_]], so you can do something like this: val feeder = tsv(“fileName”).queue // explicitly call queue to make the Array into an Iterator val scn = scenario(“foo”) .feed(feeder.map(suffixMapKey(1))) .feed(feeder.map(suffixMapKey(2))) .feed(feeder.map(suffixMapKey(3))) .feed(feeder.map(suffixMapKey(4))) .feed(feeder.map(suffixMapKey(5))) However, it won’t guarantee that the 5 records being polled are sequential, as multiple concurrent users might poll at the same time. I’ll try to think of a better solution. Cheers, Stéphane ---
**Author:** ![Loic\_Descotte](https://avatars.discourse-cdn.com/v4/letter/l/8e7dd6/32.png) [@Loic\_Descotte](https://community.gatling.io/u/Loic_Descotte)\ **Post date:** [January 11, 2013, 10:12am UTC](https://community.gatling.io/t/process-several-csv-lines-at-the-same-time-with-a-feed/223/3 "2013-01-11T10:12:39Z")
Thanks I will try this! Non sequential read is not a problem for me Regards Loïc ---
**Author:** ![Loic\_Descotte](https://avatars.discourse-cdn.com/v4/letter/l/8e7dd6/32.png) [@Loic\_Descotte](https://community.gatling.io/u/Loic_Descotte)\ **Post date:** [January 11, 2013, 10:29am UTC](https://community.gatling.io/t/process-several-csv-lines-at-the-same-time-with-a-feed/223/4 "2013-01-11T10:29:43Z")
Sorry I answered too quickly, I’m not sure to understand what I have to put in the suffixMapKey to make this work. In addition, I have to use circular stategy instead of queue, is it possible? Thanks Loic ---
**Author:** ![Excilys](https://avatars.discourse-cdn.com/v4/letter/e/8797f3/32.png) [@Excilys](https://community.gatling.io/u/Excilys)\ **Post date:** [January 11, 2013, 11:08am UTC](https://community.gatling.io/t/process-several-csv-lines-at-the-same-time-with-a-feed/223/5 "2013-01-11T11:08:30Z")
Here’s a better solution (just copy this directly into your simulation): type Record = Map[String, Any] // define an alias so there’s less boilerplate def chunkAndMerge(records: List[Record], chunkSize: Int): List[Record] = { // translate the record key with a suffix def suffixMapKey(record: Record, suffix: Int): Record = record.map { case (key, value) =\> (key + suffix) → value } // recursively split a list into chunks of a given size (exceeding records are discarded) def chunk(records: List[Record], chunks: List[List[Record]]): List[List[Record]] = { if (records.size \< chunkSize) chunks else chunk(records.drop(chunkSize), records.take(chunkSize) :: chunks) } // merge a list of records into a single one def merge(records: List[Record]): Record = records .zipWithIndex .map { case (record, index) =\> suffixMapKey(record, index) } .foldLeft(Map.empty[String, Any]) { (record, merged) =\> merged ++ record } chunk(records, Nil).reverse.map(merge) } val feeder = chunkAndMerge(csv(“foo”).toList, 5).toArray.circular // FIXME toArray shouldn’t be necessary, that’s Gatling’s fault, will fix You then just have to use it as a regular feeder. Is this clear for you? ---
**Author:** ![Loic\_Descotte](https://avatars.discourse-cdn.com/v4/letter/l/8e7dd6/32.png) [@Loic\_Descotte](https://community.gatling.io/u/Loic_Descotte)\ **Post date:** [January 11, 2013, 1:31pm UTC](https://community.gatling.io/t/process-several-csv-lines-at-the-same-time-with-a-feed/223/6 "2013-01-11T13:31:54Z")
This is working great!! I just needed to define this : type Record = Map[String, String] and to change .foldLeft(Map.empty[String, Any]) { (record, merged) =\> by .foldLeft(Map.empty[String, String]) { (record, merged) =\> Thanks a lot for your help! ---
**Author:** ![Excilys](https://avatars.discourse-cdn.com/v4/letter/e/8797f3/32.png) [@Excilys](https://community.gatling.io/u/Excilys)\ **Post date:** [January 11, 2013, 1:48pm UTC](https://community.gatling.io/t/process-several-csv-lines-at-the-same-time-with-a-feed/223/7 "2013-01-11T13:48:08Z")
Ah, sorry, maybe that's something that has changed in 2.0.0\_SNAPSHOT/master You're welcome ---
**Author:** ![Loic\_Descotte](https://avatars.discourse-cdn.com/v4/letter/l/8e7dd6/32.png) [@Loic\_Descotte](https://community.gatling.io/u/Loic_Descotte)\ **Post date:** [January 11, 2013, 2:03pm UTC](https://community.gatling.io/t/process-several-csv-lines-at-the-same-time-with-a-feed/223/8 "2013-01-11T14:03:18Z")
I think this method could be useful for a lot of other people, what about addind possibility to parse CSV in multiline mode in the galting code? ---
**Author:** ![Excilys](https://avatars.discourse-cdn.com/v4/letter/e/8797f3/32.png) [@Excilys](https://community.gatling.io/u/Excilys)\ **Post date:** [January 11, 2013, 2:14pm UTC](https://community.gatling.io/t/process-several-csv-lines-at-the-same-time-with-a-feed/223/9 "2013-01-11T14:14:30Z")
Yep, just have to think of a clean API. 😉 ---
**Author:** ![Excilys](https://avatars.discourse-cdn.com/v4/letter/e/8797f3/32.png) [@Excilys](https://community.gatling.io/u/Excilys)\ **Post date:** [January 11, 2013, 2:28pm UTC](https://community.gatling.io/t/process-several-csv-lines-at-the-same-time-with-a-feed/223/10 "2013-01-11T14:28:33Z")
[https://github.com/excilys/gatling/issues/904](https://github.com/excilys/gatling/issues/904) ---
**Author:** ![Loic\_Descotte](https://avatars.discourse-cdn.com/v4/letter/l/8e7dd6/32.png) [@Loic\_Descotte](https://community.gatling.io/u/Loic_Descotte)\ **Post date:** [January 11, 2013, 2:33pm UTC](https://community.gatling.io/t/process-several-csv-lines-at-the-same-time-with-a-feed/223/11 "2013-01-11T14:33:18Z")
Great 🙂 ---
**Author:** ![Snigdha\_Arora](https://avatars.discourse-cdn.com/v4/letter/s/839c29/32.png) [@Snigdha\_Arora](https://community.gatling.io/u/Snigdha_Arora)\ **Post date:** [February 15, 2016, 3:36am UTC](https://community.gatling.io/t/process-several-csv-lines-at-the-same-time-with-a-feed/223/12 "2016-02-15T03:36:30Z")
Hi, I need to read 1000 csv records and hit as many users as i wish and those data to be parsed and put in body of a http request. Right now with my solution i am able to read only 1 random record. Ay help is appreciated. ---
**Author:** ![annycao520](https://avatars.discourse-cdn.com/v4/letter/a/b2d939/32.png) [@annycao520](https://community.gatling.io/u/annycao520)\ **Post date:** [April 19, 2016, 8:47am UTC](https://community.gatling.io/t/process-several-csv-lines-at-the-same-time-with-a-feed/223/13 "2016-04-19T08:47:02Z")
Hello,I tried to read user csv files to get useriDs 5 by 5,For HTTP GET:get("/user/1234;1235;1236;1237;1238/"). I used “chunkAndMerge(csv(“foo”).toList, 5).toArray.circular”,but it’s error. Info: “value toList is not a member of io.gatling.core.feeder.RecordSeqFeederBuilder[String]”. eg:csv.file email ,password,userid \*\*\*\*@eadtest.ea.com,123,1234 \*\*\*\*@eadtest.ea.com,123,1235 \*\*\*\*@eadtest.ea.com,123,1236 \*\*\*\*@eadtest.ea.com,123,1237 \*\*\*\*@eadtest.ea.com,123,1238 \*\*\*\*@eadtest.ea.com,123,1239 \*\*\*\*@eadtest.ea.com,123,12310 \*\*\*\*@eadtest.ea.com,123,12311 and more 在 2013年1月11日星期五 UTC+8下午7:08:30，Stéphane Landelle写道： ---
**Author:** ![slandelle](https://dub1.discourse-cdn.com/flex013/user_avatar/community.gatling.io/slandelle/32/4_2.png) [@slandelle](https://community.gatling.io/u/slandelle)\ **Post date:** [April 19, 2016, 9:07am UTC](https://community.gatling.io/t/process-several-csv-lines-at-the-same-time-with-a-feed/223/14 "2016-04-19T09:07:46Z")
This chunkAndMerge doesn’t come from Gatling and is some custom code on your side, can’t help.