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diff --git a/middleware/node_modules/depd/Readme.md b/middleware/node_modules/depd/Readme.md new file mode 100644 index 0000000..7790670 --- /dev/null +++ b/middleware/node_modules/depd/Readme.md @@ -0,0 +1,280 @@ +# depd + +[![NPM Version][npm-version-image]][npm-url] +[![NPM Downloads][npm-downloads-image]][npm-url] +[![Node.js Version][node-image]][node-url] +[![Linux Build][travis-image]][travis-url] +[![Windows Build][appveyor-image]][appveyor-url] +[![Coverage Status][coveralls-image]][coveralls-url] + +Deprecate all the things + +> With great modules comes great responsibility; mark things deprecated! + +## Install + +This module is installed directly using `npm`: + +```sh +$ npm install depd +``` + +This module can also be bundled with systems like +[Browserify](http://browserify.org/) or [webpack](https://webpack.github.io/), +though by default this module will alter it's API to no longer display or +track deprecations. + +## API + +<!-- eslint-disable no-unused-vars --> + +```js +var deprecate = require('depd')('my-module') +``` + +This library allows you to display deprecation messages to your users. +This library goes above and beyond with deprecation warnings by +introspection of the call stack (but only the bits that it is interested +in). + +Instead of just warning on the first invocation of a deprecated +function and never again, this module will warn on the first invocation +of a deprecated function per unique call site, making it ideal to alert +users of all deprecated uses across the code base, rather than just +whatever happens to execute first. + +The deprecation warnings from this module also include the file and line +information for the call into the module that the deprecated function was +in. + +**NOTE** this library has a similar interface to the `debug` module, and +this module uses the calling file to get the boundary for the call stacks, +so you should always create a new `deprecate` object in each file and not +within some central file. + +### depd(namespace) + +Create a new deprecate function that uses the given namespace name in the +messages and will display the call site prior to the stack entering the +file this function was called from. It is highly suggested you use the +name of your module as the namespace. + +### deprecate(message) + +Call this function from deprecated code to display a deprecation message. +This message will appear once per unique caller site. Caller site is the +first call site in the stack in a different file from the caller of this +function. + +If the message is omitted, a message is generated for you based on the site +of the `deprecate()` call and will display the name of the function called, +similar to the name displayed in a stack trace. + +### deprecate.function(fn, message) + +Call this function to wrap a given function in a deprecation message on any +call to the function. An optional message can be supplied to provide a custom +message. + +### deprecate.property(obj, prop, message) + +Call this function to wrap a given property on object in a deprecation message +on any accessing or setting of the property. An optional message can be supplied +to provide a custom message. + +The method must be called on the object where the property belongs (not +inherited from the prototype). + +If the property is a data descriptor, it will be converted to an accessor +descriptor in order to display the deprecation message. + +### process.on('deprecation', fn) + +This module will allow easy capturing of deprecation errors by emitting the +errors as the type "deprecation" on the global `process`. If there are no +listeners for this type, the errors are written to STDERR as normal, but if +there are any listeners, nothing will be written to STDERR and instead only +emitted. From there, you can write the errors in a different format or to a +logging source. + +The error represents the deprecation and is emitted only once with the same +rules as writing to STDERR. The error has the following properties: + + - `message` - This is the message given by the library + - `name` - This is always `'DeprecationError'` + - `namespace` - This is the namespace the deprecation came from + - `stack` - This is the stack of the call to the deprecated thing + +Example `error.stack` output: + +``` +DeprecationError: my-cool-module deprecated oldfunction + at Object.<anonymous> ([eval]-wrapper:6:22) + at Module._compile (module.js:456:26) + at evalScript (node.js:532:25) + at startup (node.js:80:7) + at node.js:902:3 +``` + +### process.env.NO_DEPRECATION + +As a user of modules that are deprecated, the environment variable `NO_DEPRECATION` +is provided as a quick solution to silencing deprecation warnings from being +output. The format of this is similar to that of `DEBUG`: + +```sh +$ NO_DEPRECATION=my-module,othermod node app.js +``` + +This will suppress deprecations from being output for "my-module" and "othermod". +The value is a list of comma-separated namespaces. To suppress every warning +across all namespaces, use the value `*` for a namespace. + +Providing the argument `--no-deprecation` to the `node` executable will suppress +all deprecations (only available in Node.js 0.8 or higher). + +**NOTE** This will not suppress the deperecations given to any "deprecation" +event listeners, just the output to STDERR. + +### process.env.TRACE_DEPRECATION + +As a user of modules that are deprecated, the environment variable `TRACE_DEPRECATION` +is provided as a solution to getting more detailed location information in deprecation +warnings by including the entire stack trace. The format of this is the same as +`NO_DEPRECATION`: + +```sh +$ TRACE_DEPRECATION=my-module,othermod node app.js +``` + +This will include stack traces for deprecations being output for "my-module" and +"othermod". The value is a list of comma-separated namespaces. To trace every +warning across all namespaces, use the value `*` for a namespace. + +Providing the argument `--trace-deprecation` to the `node` executable will trace +all deprecations (only available in Node.js 0.8 or higher). + +**NOTE** This will not trace the deperecations silenced by `NO_DEPRECATION`. + +## Display + + + +When a user calls a function in your library that you mark deprecated, they +will see the following written to STDERR (in the given colors, similar colors +and layout to the `debug` module): + +``` +bright cyan bright yellow +| | reset cyan +| | | | +▼ ▼ ▼ ▼ +my-cool-module deprecated oldfunction [eval]-wrapper:6:22 +▲ ▲ ▲ ▲ +| | | | +namespace | | location of mycoolmod.oldfunction() call + | deprecation message + the word "deprecated" +``` + +If the user redirects their STDERR to a file or somewhere that does not support +colors, they see (similar layout to the `debug` module): + +``` +Sun, 15 Jun 2014 05:21:37 GMT my-cool-module deprecated oldfunction at [eval]-wrapper:6:22 +▲ ▲ ▲ ▲ ▲ +| | | | | +timestamp of message namespace | | location of mycoolmod.oldfunction() call + | deprecation message + the word "deprecated" +``` + +## Examples + +### Deprecating all calls to a function + +This will display a deprecated message about "oldfunction" being deprecated +from "my-module" on STDERR. + +```js +var deprecate = require('depd')('my-cool-module') + +// message automatically derived from function name +// Object.oldfunction +exports.oldfunction = deprecate.function(function oldfunction () { + // all calls to function are deprecated +}) + +// specific message +exports.oldfunction = deprecate.function(function () { + // all calls to function are deprecated +}, 'oldfunction') +``` + +### Conditionally deprecating a function call + +This will display a deprecated message about "weirdfunction" being deprecated +from "my-module" on STDERR when called with less than 2 arguments. + +```js +var deprecate = require('depd')('my-cool-module') + +exports.weirdfunction = function () { + if (arguments.length < 2) { + // calls with 0 or 1 args are deprecated + deprecate('weirdfunction args < 2') + } +} +``` + +When calling `deprecate` as a function, the warning is counted per call site +within your own module, so you can display different deprecations depending +on different situations and the users will still get all the warnings: + +```js +var deprecate = require('depd')('my-cool-module') + +exports.weirdfunction = function () { + if (arguments.length < 2) { + // calls with 0 or 1 args are deprecated + deprecate('weirdfunction args < 2') + } else if (typeof arguments[0] !== 'string') { + // calls with non-string first argument are deprecated + deprecate('weirdfunction non-string first arg') + } +} +``` + +### Deprecating property access + +This will display a deprecated message about "oldprop" being deprecated +from "my-module" on STDERR when accessed. A deprecation will be displayed +when setting the value and when getting the value. + +```js +var deprecate = require('depd')('my-cool-module') + +exports.oldprop = 'something' + +// message automatically derives from property name +deprecate.property(exports, 'oldprop') + +// explicit message +deprecate.property(exports, 'oldprop', 'oldprop >= 0.10') +``` + +## License + +[MIT](LICENSE) + +[npm-version-image]: https://img.shields.io/npm/v/depd.svg +[npm-downloads-image]: https://img.shields.io/npm/dm/depd.svg +[npm-url]: https://npmjs.org/package/depd +[travis-image]: https://img.shields.io/travis/dougwilson/nodejs-depd/master.svg?label=linux +[travis-url]: https://travis-ci.org/dougwilson/nodejs-depd +[appveyor-image]: https://img.shields.io/appveyor/ci/dougwilson/nodejs-depd/master.svg?label=windows +[appveyor-url]: https://ci.appveyor.com/project/dougwilson/nodejs-depd +[coveralls-image]: https://img.shields.io/coveralls/dougwilson/nodejs-depd/master.svg +[coveralls-url]: https://coveralls.io/r/dougwilson/nodejs-depd?branch=master +[node-image]: https://img.shields.io/node/v/depd.svg +[node-url]: https://nodejs.org/en/download/ |