.env File Validator & Linter
.env File Validator: Checks trimmed non-comment lines for optional export, an ASCII key, an equals sign, and duplicate keys; it does not parse shell semantics.
About this .env file validator & linter
.env File Validator: Checks trimmed non-comment lines for optional export, an ASCII key, an equals sign, and duplicate keys; it does not parse shell semantics Transforms and validates developer data structures locally, preventing confidential payload exposure during data wrangling.
Syntax parsing & data transformation logic
Splits pasted dotenv text into lines, skips blanks and # comments, checks optional export plus ASCII KEY=VALUE shape, and reports duplicate keys or line errors. It does not parse value syntax or expand variables.
Worked conversion & output example
Scenario: Validate two ordinary dotenv assignments.
Sample input:
Processing: Trim lines, match the limited KEY=VALUE grammar, and count unique keys.
Illustrative output:
Syntax constraints & input size limits
It does not parse quoting, escapes, interpolation, multiline values, inline comments, shell expansion, required keys, value types, or secret safety.
Data conversions and formatting in .env File Validator & Linter reflect standard structured syntax. Verify parsed outputs against your target runtime before deployment.
Local client execution boundary
Data parsing and transformations in .env File Validator & Linter execute in the local browser tab without remote data transmission.
Data format specifications & language standards
Data interchange formats and language grammar specifications:
- Standard Browser Web API / Algorithm Implementation (No single external RFC/ISO standard)
.env File Validator & Linter verification · Audit standards
How to use it
- Paste .env text.
- Ignore blank and # comment lines; accept optional export, then require an ASCII KEY=VALUE assignment.
- Read a valid variable count or the original physical line number for malformed and duplicate keys.
Frequently asked questions
What dotenv syntax does the validator inspect?+
It trims each non-comment line, accepts an optional `export`, then requires an ASCII identifier followed by `=`. It reports malformed line numbers and duplicate keys while counting valid keys.
What does the two-variable example return?+
For `FOO=bar` and `COUNT=2`, the page returns `Basic dotenv assignment shape OK (2 variables); values and quoting not parsed.` This checks the documented assignment and count path; it does not load values into a shell.
Which dotenv rules are outside this checker?+
It does not interpret quotes, escapes, interpolation, multiline values, inherited environment, command substitution, permissions, or whether another dotenv loader accepts the file.
What result should the documented example produce?+
The example run enters dotenv text, runs the validator, and reads its page result. Its tool request log contains no request carrying that entered text; ordinary page resources, extensions, and wider browser traffic are separate.