Workflow: write n8n workflow for Http Schedule Create Scheduled
Integrations: httpRequest, if, scheduleTrigger, set, splitInBatches, wait

{"meta": {"templateCredsSetupCompleted": true}, "nodes": [{"id": "b9a807c3-5847-477a-a242-2fdf5b15ba7e", "name": "API to Check existing merge request", "type": "n8n-nodes-base.httpRequest", "position": [-840, -20], "parameters": {"url": "=https://gitlab.com/<projectid>/merge_requests", "options": {"allowUnauthorizedCerts": false}, "sendQuery": true, "sendHeaders": true, "queryParameters": {"parameters": [{"name": "state", "value": "opened"}, {"name": "source_branch", "value": "=sourceBranchName"}]}, "headerParameters": {"parameters": [{"name": "PRIVATE-TOKEN", "value": "=gitlabToken"}]}}, "typeVersion": 4.2, "alwaysOutputData": true}, {"id": "42270a5a-d696-44f3-b2f5-16b2ddb3488c", "name": "Is Exists", "type": "n8n-nodes-base.if", "position": [-660, -20], "parameters": {"options": {}, "conditions": {"options": {"version": 2, "leftValue": "", "caseSensitive": true, "typeValidation": "strict"}, "combinator": "and", "conditions": [{"id": "d895b8cc-5679-442f-a1bf-d8375174a24b", "operator": {"type": "boolean", "operation": "true", "singleValue": true}, "leftValue": "={{ $node[\"API to Check existing merge request\"].data.isEmpty() }}", "rightValue": ""}]}}, "typeVersion": 2.2}, {"id": "d380c943-0525-4976-9e70-c90de1177f0c", "name": "Create New Merge Request", "type": "n8n-nodes-base.httpRequest", "position": [-440, -200], "parameters": {"url": "=https://gitlab.com/<projectid>/merge_requests", "method": "POST", "options": {"allowUnauthorizedCerts": false}, "sendBody": true, "contentType": "form-urlencoded", "sendHeaders": true, "bodyParameters": {"parameters": [{"name": "source_branch", "value": "=sourceBranchName"}, {"name": "target_branch", "value": "=targetBranchName"}, {"name": "title", "value": "=mergeTitle"}]}, "headerParameters": {"parameters": [{"name": "PRIVATE-TOKEN", "value": "=gitlabToken"}]}}, "typeVersion": 4.2}, {"id": "600a0ed5-cb68-4479-8aee-55b55f0d8630", "name": "Loop Over Items", "type": "n8n-nodes-base.splitInBatches", "position": [-440, 160], "parameters": {"options": {}}, "typeVersion": 3}, {"id": "555643cb-761c-41ec-b983-8e0194851a8d", "name": "API to CLOSE existing Merge Request", "type": "n8n-nodes-base.httpRequest", "position": [-220, 180], "parameters": {"url": "=https://gitlab.com/<projectid>/merge_requests/<merge_iid>", "method": "PUT", "options": {"allowUnauthorizedCerts": false}, "sendBody": true, "contentType": "form-urlencoded", "sendHeaders": true, "bodyParameters": {"parameters": [{"name": "state_event", "value": "close"}]}, "headerParameters": {"parameters": [{"name": "PRIVATE-TOKEN", "value": "=gitlabToken"}]}}, "typeVersion": 4.2}, {"id": "0c94b06a-80e3-4e50-8bac-2bd4015f085e", "name": "Add Custom Notes To Merge Request", "type": "n8n-nodes-base.httpRequest", "position": [-220, -200], "parameters": {"url": "=https://gitlab.com/<projectid>/merge_requests/<merge_iid>/notes", "method": "POST", "options": {"allowUnauthorizedCerts": false}, "sendBody": true, "contentType": "form-urlencoded", "sendHeaders": true, "bodyParameters": {"parameters": [{"name": "body", "value": "=<mergeComments>"}]}, "headerParameters": {"parameters": [{"name": "PRIVATE-TOKEN", "value": "=gitlabToken"}]}}, "typeVersion": 4.2}, {"id": "8e849f4f-2a52-46ba-9e0a-17126a8d966c", "name": "30 secs wait to approve merge request and pipeline to finish1", "type": "n8n-nodes-base.wait", "position": [140, -200], "webhookId": "ac7bb2de-2c6f-479a-8807-13a29d8eaf5e", "parameters": {"amount": 30}, "typeVersion": 1.1}, {"id": "05cca829-b2df-4c1e-9441-56349acc4a0d", "name": "Merge When Pipeline Succeeds", "type": "n8n-nodes-base.httpRequest", "position": [720, -200], "parameters": {"url": "=https://gitlab.com/<projectid>/merge_requests/<merge_iid>/merge", "method": "PUT", "options": {"allowUnauthorizedCerts": false}, "jsonBody": "={\n\"merge_when_pipeline_succeeds\": {{ $('setValueForMerge').item.json.merge_when_pipeline_succeeds }},\n  \"should_remove_source_branch\": {{ $('setValueForMerge').item.json.should_remove_source_branch }}\n}", "sendBody": true, "sendHeaders": true, "specifyBody": "json", "headerParameters": {"parameters": [{"name": "PRIVATE-TOKEN", "value": "=gitlabToken"}]}}, "typeVersion": 4.2}, {"id": "e3ce9cdc-5484-4b4b-8701-6b9089a1f76d", "name": "setValueForMerge", "type": "n8n-nodes-base.set", "position": [460, -200], "parameters": {"options": {}, "assignments": {"assignments": [{"id": "a22922c7-0c69-4ac1-bd15-4d289fa57737", "name": "merge_when_pipeline_succeeds", "type": "boolean", "value": false}, {"id": "17580668-84d9-4ad6-b93b-e7b6c9c0f8ea", "name": "should_remove_source_branch", "type": "boolean", "value": true}]}}, "typeVersion": 3.4}, {"id": "0d49ec98-4806-492e-a6c2-a298ed8bb11a", "name": "Schedule Trigger", "type": "n8n-nodes-base.scheduleTrigger", "position": [-1160, -20], "parameters": {"rule": {"interval": [{}]}}, "typeVersion": 1.2}], "pinData": {}, "connections": {"Is Exists": {"main": [[{"node": "Create New Merge Request", "type": "main", "index": 0}], [{"node": "Loop Over Items", "type": "main", "index": 0}]]}, "Loop Over Items": {"main": [[{"node": "API to Check existing merge request", "type": "main", "index": 0}], [{"node": "API to CLOSE existing Merge Request", "type": "main", "index": 0}]]}, "Schedule Trigger": {"main": [[{"node": "API to Check existing merge request", "type": "main", "index": 0}]]}, "setValueForMerge": {"main": [[{"node": "Merge When Pipeline Succeeds", "type": "main", "index": 0}]]}, "Create New Merge Request": {"main": [[{"node": "Add Custom Notes To Merge Request", "type": "main", "index": 0}]]}, "Add Custom Notes To Merge Request": {"main": [[{"node": "30 secs wait to approve merge request and pipeline to finish1", "type": "main", "index": 0}]]}, "API to CLOSE existing Merge Request": {"main": [[{"node": "Loop Over Items", "type": "main", "index": 0}]]}, "API to Check existing merge request": {"main": [[{"node": "Is Exists", "type": "main", "index": 0}]]}, "30 secs wait to approve merge request and pipeline to finish1": {"main": [[{"node": "setValueForMerge", "type": "main", "index": 0}]]}}}