@now/build-utils
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TypeScript
/// <reference types="node" />
/**
* `DetectorFilesystem` is an abstract class that represents a virtual filesystem
* to perform read-only operations on in order to detect which framework is being
* used.
*
* Its abstract methods must be implemented by a subclass that perform the actual
* FS operations. Example subclasses could be implemented as:
*
* - Local filesystem, which proxies the FS operations to the equivalent `fs`
* module functions.
* - HTTP filesystem, which implements the FS operations over an HTTP server
* and does not require a local copy of the files.
* - `Files` filesystem, which operates on a virtual `Files` object (i.e. from
* the `glob()` function) which could include `FileFsRef`, `FileBlob`, etc.
*
* This base class implements various helper functions for common tasks (i.e.
* read and parse a JSON file). It also includes caching for all FS operations
* so that multiple detector functions de-dup read operations on the same file
* to reduce network/filesystem overhead.
*
* **NOTE:** It's important that all instance methods in this base class are
* bound to `this` so that the `fs` object may be destructured in the detector
* functions. The easiest way to do this is to use the `=` syntax when defining
* methods in this class definition.
*/
export declare abstract class DetectorFilesystem {
protected abstract _hasPath(name: string): Promise<boolean>;
protected abstract _readFile(name: string): Promise<Buffer>;
protected abstract _isFile(name: string): Promise<boolean>;
private pathCache;
private fileCache;
private readFileCache;
constructor();
hasPath: (path: string) => Promise<boolean>;
isFile: (name: string) => Promise<boolean>;
readFile: (name: string) => Promise<Buffer>;
}