Structuring Large React Applications:
- Use feature-based structure approach (grouping by features or domains) and layered structure (grouping by type of file: components, hooks, utils, etc.);
- Feature (domain) based example: you might have a
src/features/
directory with subfolders likeauth/
,dashboard/
,products/
, etc. Inside each, you could have files likecomponents/
,hooks/
,services/
, and so on, related only to that feature. Shared resources (like common UI components or utility functions) live in a separate folder (e.g.,src/components/
for reusable UI,src/utils/
for utilities); - Avoid Deep Nesting: aim for a balance – group things meaningfully, but don’t create one-file-per-folder scenarios either.
- Use naming conventions for files: Use
kebab-case
for filenames, and some prefix component files with capital letters;
Managing Reusable Components and Utilities:
- Centralize Reusable Components: For truly shared components (used in multiple features), maintain a directory for them (e.g.,
src/components
orsrc/common/components
). Examples are buttons, modals, dropdowns, etc. Within that, you might even categorize by type (forms, layout, data-display); - Have a central place for utilities (pure functions like formatting, calculation helpers) and services (code that interacts with external APIs). A
src/utils
folder can contain things likedate.ts
,string.ts
, etc., and asrc/services
(orapi
) can contain modules for API calls (e.g.,userApi.ts
for user-related requests). With TypeScript, you can define interfaces for API responses in the same files or in a adjacentsrc/types
orsrc/interfaces
directory; - Shared State (Context/hooks): If you have context providers or custom hooks that are used app-wide (e.g., AuthProvider, useAuth, or a ThemeProvider), consider placing them in a
src/context
orsrc/providers
directory. If following feature structure, a context that is only used by one feature lives with that feature, whereas a global one (used by many features) lives in a common area; - Index Files for Barrel Imports: simplify imports, use
index.ts
barrel files in directories. For example, insrc/utils/
, export all utility functions in anindex.ts
. This way other parts of the app can import{ formatDate } from 'utils'
(assuming proper path aliases or relative path) instead of deep paths; - Be cautious not to create circular dependencies with barrels.
Handling Environment Variables and Configuration:
- Use environment variables for configuration that differs by environment (development, production, etc.) or for sensitive keys.
- Avoid magic strings for env variable names, add type definitions for
process.env
; For example, create aenv.d.ts
declaringnamespace NodeJS { interface ProcessEnv { REACT_APP_API_URL: string; } }
so thatprocess.env.REACT_APP_API_URL
is recognized by TypeScript; - Do Not Commit Secrets: Ensure that your .env files (especially those with real secrets or config) are excluded from version control (add to
.gitignore
). Instead, use sample env files (like.env.example
) to show what keys are needed; - Create a config module that reads from env and provides higher-level config. For example, a
config.ts
that exportsAPI_BASE_URL = process.env.REACT_APP_API_URL ?? ''
and other such constants. This centralizes config logic and can enforce required variables (throwing an error if a needed env is missing, to fail fast).