Templates CI (#12313)

Adds a `langchain-location` param to lint, so we can properly locate it.

Regular langchain and experimental lint steps are passing, so default
value seems to be working.

.github/workflows/_lint.yml

@@ -7,6 +7,10 @@ on:
         required: true
         type: string
         description: "From which folder this pipeline executes"
+      langchain-location:
+        required: false
+        type: string
+        description: "Relative path to the langchain library folder"
 
 env:
   POETRY_VERSION: "1.6.1"
@@ -117,8 +121,10 @@ jobs:
       - name: Install langchain editable
         working-directory: ${{ inputs.working-directory }}
         if: ${{ inputs.working-directory != 'libs/langchain' }}
+        env:
+          LANGCHAIN_LOCATION: ${{ inputs.langchain-location || '../langchain'}}
         run: |
-          pip install -e ../langchain
+          pip install -e "$LANGCHAIN_LOCATION"
 
       - name: Restore black cache
         uses: actions/cache@v3

.github/workflows/templates_ci.yml

@@ -0,0 +1,37 @@
+---
+name: templates CI
+
+on:
+  push:
+    branches: [ master ]
+  pull_request:
+    paths:
+      - '.github/actions/poetry_setup/action.yml'
+      - '.github/tools/**'
+      - '.github/workflows/_lint.yml'
+      - '.github/workflows/templates_ci.yml'
+      - 'templates/**'
+  workflow_dispatch:  # Allows to trigger the workflow manually in GitHub UI
+
+# If another push to the same PR or branch happens while this workflow is still running,
+# cancel the earlier run in favor of the next run.
+#
+# There's no point in testing an outdated version of the code. GitHub only allows
+# a limited number of job runners to be active at the same time, so it's better to cancel
+# pointless jobs early so that more useful jobs can run sooner.
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
+env:
+  POETRY_VERSION: "1.6.1"
+  WORKDIR: "templates"
+
+jobs:
+  lint:
+    uses:
+      ./.github/workflows/_lint.yml
+    with:
+      working-directory: templates
+      langchain-location: ../libs/langchain
+    secrets: inherit