# Sbt recompiles everything between workflow steps **URL:** \ **Category:** Build Environment\ **Tags:** sbt\ **Created:** [March 21, 2019, 2:47pm UTC](https://discuss.circleci.com/t/sbt-recompiles-everything-between-workflow-steps/29162 "2019-03-21T14:47:17Z")\ **Posts on this page:** 6\ **Page:** 1
**Author:** ![drobert](https://avatars.discourse-cdn.com/v4/letter/d/ce7236/32.png) [@drobert](https://discuss.circleci.com/u/drobert)\ **Post date:** [March 21, 2019, 2:47pm UTC](https://discuss.circleci.com/t/sbt-recompiles-everything-between-workflow-steps/29162/1 "2019-03-21T14:47:17Z")
Cross-posted on Stack Overflow: [https://stackoverflow.com/questions/55282629/sbt-always-recompiles-full-project-in-ci-even-with-caching](https://stackoverflow.com/questions/55282629/sbt-always-recompiles-full-project-in-ci-even-with-caching) I can’t seem to find a way to compile sources using scala/sbt in one workflow step and avoid full project recompilation on the next step. I’ve looked at posts like [How to cache SBT incremental compilation](https://discuss.circleci.com/t/how-to-cache-sbt-incremental-compilation/18746) and it is not relevant to my setup, or at least not solving it. My approach is basically this: 1. attach workspace `/home/circleci/myorg` 2. checkout code (to `/home/circleci/myorg/myproj`) 3. compile the project (all compilation artifacts should reside at or below the git/checkout directory) 4. persist `myorg/myproj`, `~/.sbt`, `~/.ivy2/cache` to the workspace In the next workflow step (job): 1. Restore workspace 2. Move `.sbt` and `.ivy2/cache` back to the `/home/circleci` dir from the workspace 3. run `sbt test` However `sbt test` recompiles the full project every time. I am unable to determine why that’s the case. The workspace with all source code and resulting compiled `.class` files should all still exist in the workspace; nothing should appear to it to have changed. Relevant circleci config: ```yaml --- version: 2 jobs: # compile and cache compilation test-compile: working_directory: /home/circleci/myteam/myproj docker: - image: myorg/teika-myproj-base:sbt-1.2.8 steps: # the directory to be persisted (cached/restored) to the next step - attach_workspace: at: /home/circleci/myteam # git pull to /home/circleci/myteam/myproj - checkout - restore_cache: # look for a pre-existing set of ~/.ivy2/cache, ~/.sbt dirs # from a prior build keys: - sbt-artifacts-{{ checksum "project/build.properties"}}-{{ checksum "build.sbt" }}-{{ checksum "project/Dependencies.scala" }}-{{ checksum "project/plugins.sbt" }}-{{ .Branch }} - restore_cache: # look for pre-existing set of 'target' dirs from a prior build keys: - build-{{ checksum "project/build.properties"}}-{{ checksum "build.sbt" }}-{{ checksum "project/Dependencies.scala" }}-{{ checksum "project/plugins.sbt" }}-{{ .Branch }} - run: # the compile step working_directory: /home/circleci/myteam/myproj command: sbt test:compile # per: https://www.scala-sbt.org/1.0/docs/Travis-CI-with-sbt.html # Cleanup the cached directories to avoid unnecessary cache updates - run: working_directory: /home/circleci command: | rm -rf /home/circleci/.ivy2/.sbt.ivy.lock find /home/circleci/.ivy2/cache -name "ivydata-*.properties" -print -delete find /home/circleci/.sbt -name "*.lock" -print -delete - save_cache: # cache ~/.ivy2/cache and ~/.sbt for subsequent builds key: sbt-artifacts-{{ checksum "project/build.properties"}}-{{ checksum "build.sbt" }}-{{ checksum "project/Dependencies.scala" }}-{{ checksum "project/plugins.sbt" }}-{{ .Branch }}-{{ .Revision }} paths: - /home/circleci/.ivy2/cache - /home/circleci/.sbt - save_cache: # cache the `target` dirs for subsequenet builds key: build-{{ checksum "project/build.properties"}}-{{ checksum "build.sbt" }}-{{ checksum "project/Dependencies.scala" }}-{{ checksum "project/plugins.sbt" }}-{{ .Branch }}-{{ .Revision }} paths: - /home/circleci/myteam/myproj/target - /home/circleci/myteam/myproj/project/target - /home/circleci/myteam/myproj/project/project/target # in circle, a 'workflow' undergoes several jobs, this first one # is 'compile', the next will run the tests (see next 'job' section # 'test-run' below). # 'persist to workspace' takes any files from this job and ensures # they 'come with' the workspace to the next job in the workflow - persist_to_workspace: root: /home/circleci/myteam # bring the git checkout, including all target dirs paths: - myproj - persist_to_workspace: root: /home/circleci # bring the big stuff paths: - .ivy2/cache - .sbt # actually runs the tests compiled in the previous job test-run: environment: SBT_OPTS: -XX:+UseConcMarkSweepGC -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseCGroupMemoryLimitForHeap -Duser.timezone=Etc/UTC -Duser.language=en -Duser.country=US docker: # run tests in the same image as before, but technically # a different instance - image: myorg/teika-myproj-base:sbt-1.2.8 steps: # bring over all files 'persist_to_workspace' in the last job - attach_workspace: at: /home/circleci/myteam # restore ~/.sbt and ~/.ivy2/cache via `mv` from the workspace # back to the home dir - run: working_directory: /home/circleci/myteam command: | [[! -d /home/circleci/.ivy2]] && mkdir /home/circleci/.ivy2 for d in .ivy2/cache .sbt; do [[-d "/home/circleci/$d"]] && rm -rf "/home/circleci/$d" if [-d "$d"]; then mv -v "$d" "/home/circleci/$d" else echo "$d does not exist" >&2 ls -la . >&2 exit 1 fi done - run: # run the tests, already compiled # note: recompiles everything every time! working_directory: /home/circleci/myteam/myproj command: sbt test no_output_timeout: 3900s workflows: version: 2 build-and-test: jobs: - test-compile - test-run: requires: - test-compile ``` ---
**Author:** ![drazisil](https://sea2.discourse-cdn.com/circleci/user_avatar/discuss.circleci.com/drazisil/32/24029_2.png) [@drazisil](https://discuss.circleci.com/u/drazisil)\ **Post date:** [March 21, 2019, 2:52pm UTC](https://discuss.circleci.com/t/sbt-recompiles-everything-between-workflow-steps/29162/2 "2019-03-21T14:52:48Z")
I’m not an sbt wizard, so hoping someone else can help here. From the other thread: > [@How to cache SBT incremental compilation](https://discuss.circleci.com/t/how-to-cache-sbt-incremental-compilation/18746/1): > > - “lib\_managed” #### \<– need this Is this something that would help, or was that project specific to them? I’m assuming sbt has to cache the compiled state somewhere that you aren’t adding to the workspace, but I have no clue where that would be. ---
**Author:** ![drobert](https://avatars.discourse-cdn.com/v4/letter/d/ce7236/32.png) [@drobert](https://discuss.circleci.com/u/drobert)\ **Post date:** [March 21, 2019, 6:12pm UTC](https://discuss.circleci.com/t/sbt-recompiles-everything-between-workflow-steps/29162/3 "2019-03-21T18:12:12Z")
I don’t see how it’s applicable here. I’m persisting the entirety of my checkout to the workspace, and that would bring lib\_managed along with it, wouldn’t it? Another issue is that “lib\_managed” only applies if you set `retrieveManaged := true` in `build.sbt`, which I understand to mean jars are downloaded here instead of (or in addition to) `~/.ivy2/cache`. I don’t have this setting enabled, so there is no lib\_managed, plus I should still have these artifacts in `~/.ivy2/cache` persisted in the workspace. ---
**Author:** ![drazisil](https://sea2.discourse-cdn.com/circleci/user_avatar/discuss.circleci.com/drazisil/32/24029_2.png) [@drazisil](https://discuss.circleci.com/u/drazisil)\ **Post date:** [March 21, 2019, 7:03pm UTC](https://discuss.circleci.com/t/sbt-recompiles-everything-between-workflow-steps/29162/4 "2019-03-21T19:03:02Z")
True, I missed that and thought you doing a single sub-directory. Will have to wait for someone who knows sbt more then I. ---
**Author:** ![drobert](https://avatars.discourse-cdn.com/v4/letter/d/ce7236/32.png) [@drobert](https://discuss.circleci.com/u/drobert)\ **Post date:** [March 29, 2019, 3:10pm UTC](https://discuss.circleci.com/t/sbt-recompiles-everything-between-workflow-steps/29162/5 "2019-03-29T15:10:58Z")
I haven’t solved the problem so I’m not updating the post, but rather am replying, but I _do_ have a workaround for my immediate problem that I might as well share. The gist is, I’m trying to separate ‘test compile’ with ‘test run’ so that I can customize JVM properties appropriately and spun up dependencies at different times to lower total machine memory pressure. What I’ve done, in a nutshell, is run scalatest from `scala -cp ... org.scalatest.tools.Runner` rather than via `sbt test` so that avoids any attempt at recompilation. The runner can operate against a directory of `.class` files. The short version is this: 1. docker container: augmented to include a scala CLI install instead of using the one SBT pulls down (unfortunate as I now need to keep these versions in sync) 2. build phase: `sbt test:compile 'inspect run' 'export test:fullClasspath' | tee >(grep -F '.jar' > ~test-classpath.txt)` - compiles but also records a copy-patseable classpath string, suitable for passing into `scala -cp VALUE_HERE` to run tests 3. test phase: `scala -cp "$(cat test-classpath.txt)" org.scalatest.tools.Runner -R target/scala-2.12/test-classes/ -u target/test-reports -oD` - runs scalatest via the runner, using compiled `.class` files in `target/scala-2.12/test-classes`, using the classpath reported on in the compile phase, and printint to stdout as well as a reports directory I don’t love this and it has some problems, but figured I’d share this workaround. ---
**Author:** ![xuwei-k](https://sea2.discourse-cdn.com/circleci/user_avatar/discuss.circleci.com/xuwei-k/32/24238_2.png) [@xuwei-k](https://discuss.circleci.com/u/xuwei-k)\ **Post date:** [February 21, 2020, 5:04am UTC](https://discuss.circleci.com/t/sbt-recompiles-everything-between-workflow-steps/29162/6 "2020-02-21T05:04:35Z")
see [https://github.com/sbt/sbt/issues/4168](https://github.com/sbt/sbt/issues/4168)