Use Node.js Modules Inside of

The video provides a guide on how to integrate Node.js modules into n8n workflows, distinguishing between built-in modules that require activation and external modules that require installation and activation. It details the process for each using command-line instructions within a Docker environment, emphasizing changes to docker-compose.yml and the creation of a Dockerfile. The guide also covers the updated procedure for n8n updates when custom modules are in use.

Using Node.js Modules in n8n #

• Node.js modules may be required for complex n8n workflows.
• Modules are referenced by require in code nodes.
• Some modules are built-in but need activation; others are external and need installation.
• A link to an article with a full list of built-in n8n modules is provided in the description.

Activating Built-in Modules (e.g., crypto) #

• Error Identification: Running a test function shows Cannot find module crypto if a built-in module is not activated.
• Accessing docker-compose.yml:
  • Navigate to the directory containing docker-compose.yml (e.g., cd ~/n8n-docker-caddy).
  • Open the file for editing (e.g., nano docker-compose.yml).
• Modifying docker-compose.yml:
  • Add NODE_FUNCTION_ALLOW_BUILTIN=crypto under the environment section.
  • Multiple built-in modules can be added as a comma-separated list (e.g., a,b,c).
  • An asterisk (*) can activate all built-in modules, but it's best practice to activate only needed ones.
• Applying Changes:
  • Save the docker-compose.yml file (Ctrl+X, Y, Enter).
  • Bring Docker down (docker-compose down).
  • Bring Docker back up (docker-compose up -d).
• Verification: Re-running the n8n workflow should resolve the built-in module error.

Installing and Activating External Modules (e.g., express) #

• Error Identification: If an external module is not installed, an error like Cannot find module express will occur.
• Custom Image Requirement: External modules require building n8n with a custom Docker image. This process does not delete existing workflows.
• Creating a Dockerfile:
  • Ensure you are in the same directory as docker-compose.yml.
  • Create or open a Dockerfile (e.g., nano Dockerfile). Note: Dockerfile must have a capital 'D'.
  • Add the following content:

    1FROM n8nio/n8n:latest
    2USER root
    3RUN npm install -g express
    

  • To install multiple external modules, list them space-separated after npm install -g (e.g., RUN npm install -g module1 module2).
  • Save the Dockerfile (Ctrl+X, Y, Enter).
• Modifying docker-compose.yml for External Modules:
  • Open docker-compose.yml for editing (e.g., nano docker-compose.yml).
  • Remove the image line under the n8n section.
  • Replace it with build: . (this tells Docker to build from the current directory where the Dockerfile is).
  • Add NODE_FUNCTION_ALLOW_EXTERNAL=express to the environment section. This can be added after the NODE_FUNCTION_ALLOW_BUILTIN line if both are used.
  • Similar to built-in modules, multiple external modules can be a comma-separated list, or an asterisk (*) can be used to allow all installed external modules. Best practice is to allow only needed ones.
  • Save docker-compose.yml (Ctrl+X, Y, Enter).
• Applying Changes:
  • Bring Docker down (docker-compose down).
  • Build the custom image (docker-compose build). This may take time and download files on first build.
  • Bring Docker back up (docker-compose up -d).
• Verification: Re-running the n8n workflow should show successful execution, confirming the external module is working.

Updating n8n with Custom Modules #

• For External Modules (and combinations):
  • Bring Docker down: docker-compose down
  • Build the custom image again: docker-compose build
  • Bring Docker back up: docker-compose up -d
  • This sequence ensures the custom Dockerfile is rebuilt with the new n8n version.
• For Built-in Modules Only (no external modules):
  • Pull the latest Docker image: docker-compose pull
  • Bring Docker down: docker-compose down
  • Bring Docker back up: docker-compose up -d

Summary Sections: #

• Introduction to Node.js Modules in n8n: Discusses the need for Node.js modules in complex n8n workflows and the two categories of modules (built-in and external).
• Activating Built-in Modules: Provides step-by-step instructions for enabling pre-installed Node.js modules like crypto through modifications to the docker-compose.yml file and Docker commands.
• Installing and Activating External Modules: Details the more involved process for using modules not built into n8n, such as express, which requires creating a Dockerfile and further modifications to docker-compose.yml, followed by building a custom Docker image.
• Updating n8n with Custom Modules: Explains the different update procedures for n8n instances depending on whether only built-in modules or external modules have been integrated.