Stream switching (#160)

README.md

@@ -75,7 +75,7 @@ steps:
           parallel: 16
 ```
 
-### Share a stream workspace between pipelines.
+### Share a stream workspace between pipelines
 
 Useful to avoid syncing duplicate data with large workspaces.
 Only allowed when there is a single buildkite agent running on the machine.
@@ -85,7 +85,10 @@ steps:
     plugins:
       - improbable-eng/perforce:
           stream: //dev/buildkite
+           # Sync each stream once
           share_workspace: true
+          # Sync once and switch streams in-place (requires share_workspace: true)
+          stream_switching: true
 ```
 
 ## Triggering Builds

hooks/pre-checkout

@@ -14,9 +14,14 @@ if [[ "${BUILDKITE_PLUGIN_PERFORCE_SHARE_WORKSPACE}" == true ]] ; then
       echo "Error: You cannot share stream workspaces when running more than one agent" >&2
       exit 1
     fi
-    # Sanitize //depot/stream-name to __depot_stream-name
-    SANITIZED_STREAM=$(echo $STREAM | python -c "import sys; print(sys.stdin.read().replace('/', '_'));")
-
+    if [[ "${BUILDKITE_PLUGIN_PERFORCE_STREAM_SWITCHING}" == true ]] ; then
+      echo "Stream switching enabled"
+      # Sanitize '//depot/stream-name' to 'depot'
+      SANITIZED_STREAM=$(echo $STREAM | python -c "import sys; print(sys.stdin.read().split('/')[2]);")
+    else # Create a directory per-stream
+      # Sanitize '//depot/stream-name' to '__depot_stream-name'
+      SANITIZED_STREAM=$(echo $STREAM | python -c "import sys; print(sys.stdin.read().replace('/', '_'));")
+    fi
     # Instead of builds/<agent_number>/<pipeline>, checkout to builds/<stream_name>
     PERFORCE_CHECKOUT_PATH="${BUILDKITE_BUILD_CHECKOUT_PATH}/../../${SANITIZED_STREAM}"
     export BUILDKITE_BUILD_CHECKOUT_PATH="${PERFORCE_CHECKOUT_PATH}"

python/test_perforce.py

@@ -90,6 +90,7 @@ def test_fixture(capsys, server):
     assert repo.info()['serverAddress'] == server
 
     # To change the fixture server, uncomment the line below with 'store_server' and put a breakpoint on it
+    # Change __P4D_TIMEOUT__ to 'None' or an otherwise large amount of time
     # Run unit tests in the debugger and hit the breakpoint
     # Log in using details printed to stdout (port/user) via p4v or the command line
     # Make changes to the p4 server
@@ -104,7 +105,8 @@ def test_fixture(capsys, server):
     depotfile_to_content = {depotfile: repo.perforce.run_print(depotfile)[1] for depotfile in depotfiles}
     assert depotfile_to_content == {
         "//depot/file.txt": "Hello World\n",
-        "//stream-depot/main/file.txt": "Hello Stream World\n"
+        "//stream-depot/main/file.txt": "Hello Stream World\n",
+        "//stream-depot/dev/file.txt": "Hello Stream World (dev)\n",
     }
 
     # Check submitted changes
@@ -132,6 +134,16 @@ def test_fixture(capsys, server):
             'depotFile': ['//depot/file.txt'],
             'desc': 'modify //depot/file.txt\n'
         },
+        '7': {
+            'action': ['branch'],
+            'depotFile': ['//stream-depot/dev/file.txt'],
+            'desc': 'Copy files from //stream-depot/main to //stream-depot/dev\n'
+        },
+        '8': {
+            'action': ['edit'],
+            'depotFile': ['//stream-depot/dev/file.txt'],
+            'desc': 'Update contents of //stream-depot/dev/file.txt\n'
+        }
     }
 
     # Check shelved changes
@@ -332,6 +344,21 @@ def test_client_migration(server, tmpdir):
         synced = repo.sync() # Flushes to match previous client, since p4config is there on disk
         assert synced == [], "Should not have synced any files in second client"
 
+def test_stream_switching(server, tmpdir):
+    """Test stream-switching within the same depot"""
+    repo = P4Repo(root=tmpdir, stream='//stream-depot/main')
+    synced = repo.sync()
+    assert len(synced) > 0, "Didn't sync any files"
+    with open(os.path.join(tmpdir, "file.txt")) as content:
+        assert content.read() == "Hello Stream World\n", "Unexpected content in workspace file"    
+
+    # Re-use the same checkout directory, but switch streams
+    repo = P4Repo(root=tmpdir, stream='//stream-depot/dev')
+    repo.sync()
+    assert len(synced) > 0, "Didn't sync any files"
+    with open(os.path.join(tmpdir, "file.txt")) as content:
+        assert content.read() == "Hello Stream World (dev)\n", "Unexpected content in workspace file"    
+
 
 # def test_live_server():
 #     """Reproduce production issues quickly by writing tests which run against a real server"""