trigger documentation deployment automatically

Author: nicolaskruchten

.circleci/config.yml

@@ -397,7 +397,8 @@ jobs:
     steps:
       - add_ssh_keys:
           fingerprints:
-            - "3e:4b:19:1c:c2:d1:92:dd:bf:f8:c9:d6:a6:78:69:2a"
+            - "3e:4b:19:1c:c2:d1:92:dd:bf:f8:c9:d6:a6:78:69:2a" #plotly.py-docs (built)
+            - "c0:55:31:66:74:4b:c8:fb:46:d4:b6:4e:5d:ba:81:b7" #documentation (s-d-m)
 
       - checkout
 
@@ -459,6 +460,18 @@ jobs:
             rm -rf build/html build/ipynb
             cd ..
 
+      - run:
+          name: trigger doc build
+          command: |
+            if [ "${CIRCLE_BRANCH}" == "doc-prod" ]; then
+              git clone --depth=1 --branch=source-design-merge https://github.com/plotly/documentation.git
+              cd documentation
+              git commit --allow-empty -m "deploying https://github.com/plotly/plotly.py/commit/${CIRCLE_SHA1}"
+              git push
+              cd ..
+              rm -rf documentation
+            fi
+
       - run:
           name: make doc
           command: |