snap: build fixes (iterative#3990)

* snap: drop sudo

Fixes iterative#3989

* snap: ci: fix builds

* snap: ci: developer notifications

* snap: minimise size

* debug commit

* Revert "snap: minimise size"

This reverts commit 77b41a9.

* fix image info

* Revert "debug commit"

This reverts commit 232baf0.

* snap: v1 channels

Related: iterative#3872

.travis.yml

@@ -98,8 +98,12 @@ jobs:
      - name: lxd
        channel: stable
     env:
-    - SNAPCRAFT_IMAGE_INFO: '{"build_url": "$TRAVIS_BUILD_URL"}'
+    - SNAPCRAFT_IMAGE_INFO: |
+        '{"build_url": "$TRAVIS_JOB_WEB_URL"}'
+    - SNAPCRAFT_BUILD_ENVIRONMENT: lxd
+    - SNAPCRAFT_BUILD_INFO: 1  # https://snapcraft.io/blog/introducing-developer-notifications-for-snap-security-updates
     install:
+    - sudo usermod --append --groups lxd $USER
     - sudo /snap/bin/lxd.migrate -yes
     - sudo /snap/bin/lxd waitready
     - sudo /snap/bin/lxd init --auto

scripts/build_snap.sh

@@ -7,7 +7,7 @@ if [ ! -d "dvc" ]; then
   exit 1
 fi
 
-sudo snapcraft --use-lxd
+sg lxd -c snapcraft
 
 pip uninstall -y dvc
 if which dvc; then

scripts/ci/before_install.sh

@@ -53,10 +53,10 @@ fi
 
 if [[ -n "$TRAVIS_TAG" ]]; then
   if [[ $(echo "$TRAVIS_TAG" | grep -E '^[0-9]+\.[0-9]+\.[0-9]+$') ]]; then
-    echo "export SNAP_CHANNEL=stable" >>env.sh
+    echo "export SNAP_CHANNEL=stable,v1/stable" >>env.sh
   else
-    echo "export SNAP_CHANNEL=beta" >>env.sh
+    echo "export SNAP_CHANNEL=beta,v1/beta" >>env.sh
   fi
 else
-  echo "export SNAP_CHANNEL=edge" >>env.sh
+  echo "export SNAP_CHANNEL=edge,v1/edge" >>env.sh
 fi