ENV File Parser — .env to JSON

Introduction

Twelve-factor apps load configuration from environment variables, usually authored as .env files during development. Nested values, export prefixes, variable expansion, and multiline secrets complicate mental parsing — docker-compose fails with cryptic errors when a quote is unmatched. Pasting .env into chat leaks secrets; parsing locally in the browser avoids upload while you debug structure.

Certoflow's ENV File Parser converts simple .env syntax to JSON object notation. Skips blank lines and # comments. Splits on first =. Strips optional surrounding single or double quotes from values. Live JSON output with two-space indent. Not a full dotenv specification implementation — no ${VAR} expansion or export keyword. Pair with Gitignore Generator to keep .env out of Git, JSON Formatter for further manipulation, and TOML to JSON when migrating config formats.

What this tool does

Syntax	Handling
KEY=value	Parsed to JSON key-value
# comment	Ignored
Blank lines	Ignored
KEY="quoted"	Quotes stripped from value
KEY='quoted'	Single quotes stripped
Lines without =	Skipped

Default sample input demonstrates API_KEY=secret and DEBUG=true. Output updates via useMemo as you edit.

How it works

for (const line of text.split("\n")) {
  const trimmed = line.trim();
  if (!trimmed || trimmed.startsWith("#")) continue;
  const eq = trimmed.indexOf("=");
  if (eq === -1) continue;
  const key = trimmed.slice(0, eq).trim();
  let val = trimmed.slice(eq + 1).trim();
  if ((val.startsWith('"') && val.endsWith('"')) || (val.startsWith("'") && val.endsWith("'"))) {
    val = val.slice(1, -1);
  }
  out[key] = val;
}

All values remain strings in JSON output — true stays "true" unless you manually coerce. No type inference for booleans or numbers.

Real-world examples

Onboarding documentation

New hire pastes sanitized .env.example (no real secrets) to see required keys as JSON checklist before API Key Generator fills placeholders.

Debugging docker-compose env_file

Compare parsed JSON against compose environment block expectations — spot typos like DATABSE_URL.

CI secret mapping

Map parsed keys to GitHub Actions env: YAML structure manually after visual JSON inspection.

Contrasting with production parsers

Document that export FOO=bar lines are skipped — strip export prefix before parse or enhance locally.

Feeding application config mocks

Copy JSON into test fixtures validated by JSON Validator for unit tests of config loaders.

Common mistakes

Pasting production secrets into any browser tab. Certoflow is local, but screen sharing and extensions remain risks. Use .env.example values.

Expecting boolean types. DEBUG=true becomes string "true" — application must coerce.

Values containing = signs. Only first = splits — CONNECTION=host=db value is host=db correctly; keys cannot contain unquoted =.

Multiline values. Not supported — PEM keys and multiline JSON break parser.

Variable interpolation. ${HOME}/data stays literal string — no expansion.

Duplicate keys. Later lines overwrite earlier in object — JSON duplicate keys invalid in strict parsers but JavaScript object last-wins.

Use cases

Developers visualizing env file structure.

DevOps engineers translating dotenv to JSON config prototypes.

Students learning environment variable conventions.

QA testers verifying example env completeness.

Technical writers documenting configuration keys.

Security reviewers confirming no unexpected keys in examples.

FAQ

Full dotenv spec?

No. Simple KEY=VALUE subset only.

Comments supported?

Yes, lines starting with # after trim.

Quote handling?

Surrounding ' or " removed from values.

Numeric values?

Remain strings in JSON output.

Invalid parse output?

Malformed input may yield partial JSON — validate with JSON Validator.

Uploaded?

No.

export keyword?

Not parsed — remove export prefix manually.

Multiline secrets?

Not supported.

Related?

Gitignore Generator, JSON Formatter.

Offline?

Yes.

dotenv versus structured config

Flat .env files excel at twelve-factor deployment — environment variables injected at runtime without committing secrets. They scale poorly when configuration becomes hierarchical: multiple services sharing partial settings, typed nested objects, or feature flags with metadata. Teams outgrow dotenv and adopt TOML, YAML, or JSON with schema validation. Certoflow's parser helps during the flat phase — inspect keys as JSON before writing importers. When migrating upward, compare parsed output structure with TOML to JSON results for the same logical settings. Never commit live .env files; Gitignore Generator templates list .env and .env.local explicitly. For public documentation, maintain .env.example with placeholder values generated by Password Generator or API Key Generator — parse examples here to verify every documented key appears in application startup validation errors when missing.

Quoted values and special characters

Values wrapped in double or single quotes lose their quotes in JSON output — the parser strips delimiters when both start and end match. Interior quotes without escaping are not supported; KEY="say \"hi\"" will not parse as intended. Values containing leading or trailing spaces outside quotes are trimmed once on the value side after the equals sign. Export prefix export KEY=value common in shell sourcing is not recognized — remove export before parsing or keys will be wrong. For production secret management, treat parsed JSON as a structural preview only; rotate any secret that ever appeared in a browser field on shared hardware regardless of local processing claims.