build roles: create build_work_dir and redirect caches per-roleHEADmain

Each build role now creates build_work_dir itself and sets its own toolchain's
cache env (GOPATH/GOCACHE/GOMODCACHE, CARGO_HOME, npm cache, MIX/HEX) on its
build tasks, so the roles are self-contained instead of relying on a play-level
environment and pre_task.

1 files changed, 12 insertions, 0 deletions

diff --git a/bin/build/tasks/main.yaml b/bin/build/tasks/main.yaml
index 2a29635..8da49b6 100644
--- a/bin/build/tasks/main.yaml
+++ b/bin/build/tasks/main.yaml
@@ -1,5 +1,14 @@
 ---
 
+- name: ensure build work dir exists
+  become: yes
+  file:
+    path: "{{build_work_dir}}"
+    state: "directory"
+    owner: "{{ansible_user}}"
+    group: "{{ansible_user}}"
+    mode: "0755"
+
 - name: install cargo
   become: yes
   apt: name="cargo"
@@ -20,6 +29,9 @@
   command: "cargo build --release"
   args:
     chdir: "{{bin_build_dir}}"
+  # Keep the cargo cache on build_work_dir (the SSD) instead of the SD card.
+  environment:
+    CARGO_HOME: "{{build_work_dir}}/.cargo"
   when: not build_file.stat.exists
 
 - name: create build server dir