Collection File Format

Overview

Bruno collections are directories containing .bru files. Collections can have:

collection.bru - Collection-level settings and scripts
folder.bru - Folder-level metadata files
Environment files - Variable definitions for different environments

Collection Structure

my-collection/
├── collection.bru          # Collection settings (optional)
├── environments/
│   ├── dev.bru            # Development environment
│   ├── staging.bru        # Staging environment
│   └── prod.bru           # Production environment
├── users/
│   ├── folder.bru         # Folder metadata
│   ├── get-user.bru       # Individual requests
│   ├── create-user.bru
│   └── delete-user.bru
└── auth/
    ├── folder.bru
    ├── login.bru
    └── logout.bru

Collection File

The collection.bru file defines collection-level settings that apply to all requests.

Basic Collection

headers {
  x-api-version: 1.0
  user-agent: Bruno/1.0
}

auth {
  mode: bearer
}

auth:bearer {
  token: {{collectionToken}}
}

vars:pre-request {
  baseUrl: https://api.example.com
  apiVersion: v1
}

script:pre-request {
  console.log('Collection pre-request script');
}

script:post-response {
  console.log('Collection post-response script');
}

tests {
  test("Collection-level test", function() {
    expect(res.getStatus()).to.be.below(500);
  });
}

docs {
  # My API Collection
  
  This collection contains all endpoints for the Example API.
}

Collection Blocks

headers

Headers applied to all requests in the collection:

headers {
  x-api-version: 1.0
  x-client-id: bruno-client
  accept: application/json
}

auth

Default authentication mode for the collection:

auth {
  mode: bearer
}

Supported modes: none, basic, bearer, digest, awsv4, oauth2, wsse, apikey

auth:*

Authentication credentials for the collection:

auth:bearer {
  token: {{token}}
}

auth:basic {
  username: {{username}}
  password: {{password}}
}

vars:pre-request

Variables set before each request:

vars:pre-request {
  baseUrl: https://api.example.com
  timestamp: {{$timestamp}}
}

vars:post-response

Variables extracted after each response:

vars:post-response {
  lastRequestId: $res.body.requestId
}

script:pre-request

Script executed before each request:

script:pre-request {
  const timestamp = Date.now();
  bru.setVar('timestamp', timestamp);
}

script:post-response

Script executed after each response:

script:post-response {
  if (res.getStatus() === 401) {
    console.log('Authentication required');
  }
}

tests

Tests run for all requests:

tests {
  test("Status should not be 5xx", function() {
    expect(res.getStatus()).to.be.below(500);
  });
}

docs

Collection documentation:

docs {
  # API Collection
  
  Collection description and usage notes.
}

Complete Collection Example

headers {
  accept: application/json
  x-api-version: 2.0
  x-client-name: bruno
}

auth {
  mode: bearer
}

auth:bearer {
  token: {{authToken}}
}

vars:pre-request {
  baseUrl: https://api.example.com
  apiVersion: v2
  defaultTimeout: 30000
}

vars:post-response {
  lastResponseTime: $res.responseTime
  lastStatus: $res.status
}

script:pre-request {
  const timestamp = Date.now();
  const requestId = crypto.randomUUID();
  
  bru.setVar('timestamp', timestamp);
  bru.setVar('requestId', requestId);
  
  console.log(`[${requestId}] Starting request at ${timestamp}`);
}

script:post-response {
  const status = res.getStatus();
  const time = res.getResponseTime();
  
  console.log(`Response: ${status} in ${time}ms`);
  
  // Handle token refresh
  if (status === 401) {
    console.warn('Authentication token expired');
  }
  
  // Store response metadata
  bru.setVar('lastResponseStatus', status);
}

tests {
  test("Response should be successful", function() {
    const status = res.getStatus();
    expect(status).to.be.at.least(200);
    expect(status).to.be.below(400);
  });
  
  test("Response should be timely", function() {
    expect(res.getResponseTime()).to.be.below(5000);
  });
  
  test("Content-Type should be JSON", function() {
    const contentType = res.getHeader('content-type');
    expect(contentType).to.include('application/json');
  });
}

docs {
  # Example API Collection
  
  Complete API collection for Example.com services.
  
  ## Authentication
  All requests require a Bearer token. Set `authToken` in your environment.
  
  ## Rate Limiting
  - 1000 requests per hour per token
  - 100 requests per minute per token
  
  ## Base URL
  - Production: https://api.example.com
  - Staging: https://staging-api.example.com
  - Development: http://localhost:3000
  
  ## Support
  For issues, contact api-support@example.com
}

Folder Files

The folder.bru file contains metadata for organizing requests within folders.

meta {
  name: User Management
  seq: 5
}

name

string

required

Display name for the folder

seq

number

Sequence number for ordering folders

Folder Example

meta {
  name: Authentication Endpoints
  seq: 1
}

Environment Files

Environment files define variables for different environments (dev, staging, production).

Environment File Location

Environment files are stored in the environments/ directory:

collection/
└── environments/
    ├── dev.bru
    ├── staging.bru
    ├── prod.bru
    └── local.bru

Environment File Format

vars {
  baseUrl: https://api.example.com
  apiKey: your-api-key-here
  timeout: 30000
  debugMode: false
}

Environment Variables

Do not commit sensitive data like API keys or passwords to version control. Use local environments or secret management.

Development Environment

vars {
  baseUrl: http://localhost:3000
  apiKey: dev-api-key
  dbHost: localhost
  dbPort: 5432
  debugMode: true
  logLevel: debug
}

Staging Environment

vars {
  baseUrl: https://staging-api.example.com
  apiKey: {{STAGING_API_KEY}}
  dbHost: staging-db.example.com
  dbPort: 5432
  debugMode: true
  logLevel: info
}

Production Environment

vars {
  baseUrl: https://api.example.com
  apiKey: {{PROD_API_KEY}}
  dbHost: prod-db.example.com
  dbPort: 5432
  debugMode: false
  logLevel: error
  enableCaching: true
  cacheTimeout: 3600
}

Variable Precedence

Variables are resolved in the following order (highest to lowest priority):

Request variables - Set in vars:pre-request within the request
Environment variables - Set in the active environment file
Collection variables - Set in collection.bru
Built-in variables - System variables like {{$uuid}}

Request-level variables override environment and collection variables.

Variable Syntax

Enabling/Disabling Variables

vars {
  enabled_var: value
  ~disabled_var: value
}

Disabled variables (prefixed with ~) are not applied.

Local Variables

Variables prefixed with @ are local and not persisted:

vars:pre-request {
  apiKey: {{API_KEY}}
  @temporaryToken: generated-token
}

Referencing Environment Variables

vars {
  apiUrl: https://{{API_HOST}}/api
  secretKey: {{SECRET_KEY}}
}

Environment variables in {{}} are resolved from:

Process environment variables
.env files
System environment

OAuth 2.0 Configuration

Collections can define OAuth 2.0 authentication with additional parameters:

OAuth 2.0 Authorization Request

auth:oauth2:additional_params:auth_req:headers {
  x-custom-header: value
}

auth:oauth2:additional_params:auth_req:queryparams {
  custom_param: value
}

OAuth 2.0 Access Token Request

auth:oauth2:additional_params:access_token_req:headers {
  x-tenant-id: {{tenantId}}
}

auth:oauth2:additional_params:access_token_req:queryparams {
  scope: extended
}

auth:oauth2:additional_params:access_token_req:body {
  custom_claim: value
}

OAuth 2.0 Refresh Token Request

auth:oauth2:additional_params:refresh_token_req:headers {
  x-refresh-source: bruno
}

auth:oauth2:additional_params:refresh_token_req:queryparams {
  grant_type: refresh_token
}

auth:oauth2:additional_params:refresh_token_req:body {
  client_info: bruno-client
}

Complete Collection Setup

Directory Structure

api-collection/
├── collection.bru
├── environments/
│   ├── dev.bru
│   ├── staging.bru
│   └── prod.bru
├── auth/
│   ├── folder.bru
│   ├── login.bru
│   ├── logout.bru
│   └── refresh-token.bru
├── users/
│   ├── folder.bru
│   ├── list-users.bru
│   ├── get-user.bru
│   ├── create-user.bru
│   ├── update-user.bru
│   └── delete-user.bru
└── posts/
    ├── folder.bru
    ├── list-posts.bru
    ├── get-post.bru
    ├── create-post.bru
    └── delete-post.bru

collection.bru

headers {
  accept: application/json
  content-type: application/json
  user-agent: Bruno API Client
}

auth {
  mode: bearer
}

auth:bearer {
  token: {{authToken}}
}

vars:pre-request {
  requestId: {{$uuid}}
  timestamp: {{$timestamp}}
}

script:pre-request {
  const env = bru.getEnvName();
  console.log(`Running in ${env} environment`);
}

tests {
  test("Status should be valid", function() {
    expect(res.getStatus()).to.be.at.least(200);
  });
}

environments/dev.bru

vars {
  baseUrl: http://localhost:3000
  authToken: dev-token-12345
  apiKey: dev-api-key
  debugMode: true
}

environments/prod.bru

vars {
  baseUrl: https://api.example.com
  authToken: {{PROD_AUTH_TOKEN}}
  apiKey: {{PROD_API_KEY}}
  debugMode: false
}

auth/folder.bru

meta {
  name: Authentication
  seq: 1
}

users/folder.bru

meta {
  name: User Management
  seq: 2
}

Best Practices

Use Environments

Create separate environments for dev, staging, and production with appropriate base URLs and credentials.

Secure Secrets

Never commit sensitive data. Use environment variable references like {{SECRET_KEY}} and .env files.

Collection Scripts

Use collection-level scripts for common logic like authentication, logging, and error handling.

Organize Folders

Group related requests in folders with descriptive names and sequence numbers.

Tips

Use collection-level headers for common headers like accept, user-agent, and API versioning.

Set base URLs in environment variables to easily switch between environments.

Use collection-level tests to validate common requirements like response times and status codes.

Bru Syntax

Complete Bru language syntax reference

Request Format

Request file format specification

​Overview

​Collection Structure

​Collection File

​Basic Collection

​Collection Blocks

​Complete Collection Example

​Folder Files

​Folder Example

​Environment Files

​Environment File Location

​Environment File Format

​Environment Variables

​Development Environment

​Staging Environment

​Production Environment

​Variable Precedence

​Variable Syntax

​Enabling/Disabling Variables

​Local Variables

​Referencing Environment Variables

​OAuth 2.0 Configuration

​OAuth 2.0 Authorization Request

​OAuth 2.0 Access Token Request

​OAuth 2.0 Refresh Token Request

​Complete Collection Setup

​Directory Structure

​collection.bru

​environments/dev.bru

​environments/prod.bru

​auth/folder.bru

​users/folder.bru

​Best Practices

Use Environments

Secure Secrets

Collection Scripts

Organize Folders

​Tips

​See Also

Bru Syntax

Request Format

Overview

Collection Structure

Collection File

Basic Collection

Collection Blocks

Complete Collection Example

Folder Files

Folder Example

Environment Files

Environment File Location

Environment File Format

Environment Variables

Development Environment

Staging Environment

Production Environment

Variable Precedence

Variable Syntax

Enabling/Disabling Variables

Local Variables

Referencing Environment Variables

OAuth 2.0 Configuration

OAuth 2.0 Authorization Request

OAuth 2.0 Access Token Request

OAuth 2.0 Refresh Token Request

Complete Collection Setup

Directory Structure

collection.bru

environments/dev.bru

environments/prod.bru

auth/folder.bru

users/folder.bru

Best Practices

Tips

See Also