lix-website/themes/lix/assets/bootstrap/node_modules/streamroller/lib/moveAndMaybeCompressFile.js
2024-04-26 22:49:34 -06:00

107 lines
4.1 KiB
JavaScript

const debug = require('debug')('streamroller:moveAndMaybeCompressFile');
const fs = require('fs-extra');
const zlib = require('zlib');
const _parseOption = function(rawOptions){
const defaultOptions = {
mode: parseInt("0600", 8),
compress: false,
};
const options = Object.assign({}, defaultOptions, rawOptions);
debug(`_parseOption: moveAndMaybeCompressFile called with option=${JSON.stringify(options)}`);
return options;
};
const moveAndMaybeCompressFile = async (
sourceFilePath,
targetFilePath,
options
) => {
options = _parseOption(options);
if (sourceFilePath === targetFilePath) {
debug(`moveAndMaybeCompressFile: source and target are the same, not doing anything`);
return;
}
if (await fs.pathExists(sourceFilePath)) {
debug(
`moveAndMaybeCompressFile: moving file from ${sourceFilePath} to ${targetFilePath} ${
options.compress ? "with" : "without"
} compress`
);
if (options.compress) {
await new Promise((resolve, reject) => {
let isCreated = false;
// to avoid concurrency, the forked process which can create the file will proceed (using flags wx)
const writeStream = fs.createWriteStream(targetFilePath, { mode: options.mode, flags: "wx" })
// wait until writable stream is valid before proceeding to read
.on("open", () => {
isCreated = true;
const readStream = fs.createReadStream(sourceFilePath)
// wait until readable stream is valid before piping
.on("open", () => {
readStream.pipe(zlib.createGzip()).pipe(writeStream);
})
.on("error", (e) => {
debug(`moveAndMaybeCompressFile: error reading ${sourceFilePath}`, e);
// manually close writable: https://nodejs.org/api/stream.html#readablepipedestination-options
writeStream.destroy(e);
});
})
.on("finish", () => {
debug(`moveAndMaybeCompressFile: finished compressing ${targetFilePath}, deleting ${sourceFilePath}`);
// delete sourceFilePath
fs.unlink(sourceFilePath)
.then(resolve)
.catch((e) => {
debug(`moveAndMaybeCompressFile: error deleting ${sourceFilePath}, truncating instead`, e);
// fallback to truncate
fs.truncate(sourceFilePath)
.then(resolve)
.catch((e) => {
debug(`moveAndMaybeCompressFile: error truncating ${sourceFilePath}`, e);
reject(e);
});
});
})
.on("error", (e) => {
if (!isCreated) {
debug(`moveAndMaybeCompressFile: error creating ${targetFilePath}`, e);
// do not do anything if handled by another forked process
reject(e);
} else {
debug(`moveAndMaybeCompressFile: error writing ${targetFilePath}, deleting`, e);
// delete targetFilePath (taking as nothing happened)
fs.unlink(targetFilePath)
.then(() => { reject(e); })
.catch((e) => {
debug(`moveAndMaybeCompressFile: error deleting ${targetFilePath}`, e);
reject(e);
});
}
});
}).catch(() => {});
} else {
debug(`moveAndMaybeCompressFile: renaming ${sourceFilePath} to ${targetFilePath}`);
try {
await fs.move(sourceFilePath, targetFilePath, { overwrite: true });
} catch (e) {
debug(`moveAndMaybeCompressFile: error renaming ${sourceFilePath} to ${targetFilePath}`, e);
/* istanbul ignore else: no need to do anything if file does not exist */
if (e.code !== "ENOENT") {
debug(`moveAndMaybeCompressFile: trying copy+truncate instead`);
try {
await fs.copy(sourceFilePath, targetFilePath, { overwrite: true });
await fs.truncate(sourceFilePath);
} catch (e) {
debug(`moveAndMaybeCompressFile: error copy+truncate`, e);
}
}
}
}
}
};
module.exports = moveAndMaybeCompressFile;