Flujo de trabajo de n8n: construir una API de MongoDB con validación de nombres de colección y respuesta HTTP

• •Cadena de conexión de MongoDB
• •Punto final de HTTP Webhook (n8n generará automáticamente)

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        "content": "# n8n Workflow: Build a MongoDB API with Collection Name Validation and HTTP Responses\nAuthor: [Samuel Heredia - LinkedIn](https://www.linkedin.com/in/samuel-heredia-2b5b7a98/)\n## **Objective**\nExpose a secure HTTP endpoint that retrieves all documents from a given MongoDB collection. The workflow validates the collection name, queries MongoDB, transforms the response, and returns the result in a clean JSON format.\n\n## **Workflow Steps**"
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        "jsCode": "// Function to replace the '_id' key with 'id' in each object of the array\nfunction replaceIdKey(arr) {\nreturn arr.map(item => {\n// Create a shallow copy of the object to avoid mutating the original\nconst newItem = { ...item };\n// If the object has an '_id' property, replace it with 'id'\nif (newItem._id !== undefined) {\nnewItem.id = newItem._id;\ndelete newItem._id;\n}\nreturn newItem;\n});\n}\n\n// Example usage in n8n Code node:\n// Get the input array from all items\nconst inputArray = $input.all().map(i => i.json);\n// Apply the function to replace '_id' with 'id'\nconst outputArray = replaceIdKey(inputArray);\n\n// If you want to return each object as a separate item:\nreturn outputArray.map(obj => ({ json: obj }));\n\n// If you want to return the whole array as a single item, use this instead:\n// return [{ json: outputArray }];"
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        "jsCode": "const name = $input.first().json.params.nameCollection;\nconst regex = /^(?!system\\.)[a-zA-Z0-9._]{1,120}$/;\n\nif (!name) {\n  return { valid: false, message: 'The name Collection cannot be empty.' };\n}\n\nif (!regex.test(name)) {\n  let message = 'The name of the collection does not comply with the rules:';\n  if (name.startsWith('system.')) {\n    message += \"You cannot start with 'system.'. \";\n  }\n  if (name.length < 1 || name.length > 120) {\n    message += 'It must be between 1 and 120 characters long. ';\n  }\n  if (/[^a-zA-Z0-9._]/.test(name)) {\n    message += 'Only letters, numbers, and underscores are allowed. (_) and point (.). ';\n  }\n  return { valid: false, message };\n}\n\nreturn { valid: true, collection: name };"
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        "content": "## 1. Webhook Node (HTTP GET)\n\n A webhook endpoint is exposed with the following pattern:\n\n```perl\nhttps://<your-n8n-instance>/webhook/<uuid>/:nameCollection\n```\n\nThe :nameCollection parameter in the URL defines which MongoDB collection should be queried.\n\n"
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        "content": "## 2. Code Node (Validation Layer)\n\nFor security reasons, the provided collection name is validated before any database query is made.\n\nThe regex used is:\n\n```perl\n^(?!system\\.)[a-zA-Z0-9._]{1,120}$\n```\n\nWhy this matters:\nPrevents querying reserved collections (e.g., system.*).\nAvoids injection attempts with malformed names.\nEnsures collection names follow MongoDB’s recommended conventions"
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        "content": "## 3. IF Node (Validation Check)\n\n- If the validation passes ✅: the workflow continues to query MongoDB.\n\n- If validation fails ❌: the workflow returns a structured HTTP 400 response:\n\n\n```json\n{\n  \"code\": 400,\n  \"message\": \"{{ $json.message }}\"\n}\n```"
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        "content": "## 4. MongoDB Node (Data Retrieval)\n\n- Queries the specified collection and retrieves all documents.\n\n- Results are sent downstream for formatting."
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        "content": "## 5. Code Node (Data Transformation)\n\n- MongoDB documents include an _id field by default.\n\n- This step transforms each record by renaming _id → id to improve readability and API consistency."
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        "content": "## 6. Respond to Webhook Node (Final Response)\n\n- Sends back the cleaned MongoDB data as a JSON response to the original HTTP request.\n\n- Ensures clients receive a well-structured, ready-to-use dataset."
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        "content": "## 3.A. Responde code 400\nI respond with standard http :) "
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        "content": "## 1"
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        "content": "## 2"
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        "content": "## 3"
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        "content": "## 3.A."
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        "content": "## 4"
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        "content": "## 5"
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        "content": "## 6"
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