overleaf/services/filestore/app/js/FileConverter.js
2020-01-07 09:22:53 +00:00

105 lines
2.3 KiB
JavaScript

const metrics = require('metrics-sharelatex')
const logger = require('logger-sharelatex')
const Settings = require('settings-sharelatex')
const { callbackify } = require('util')
const safeExec = require('./SafeExec').promises
const { ConversionError } = require('./Errors')
const APPROVED_FORMATS = ['png']
const FOURTY_SECONDS = 40 * 1000
const KILL_SIGNAL = 'SIGTERM'
module.exports = {
convert: callbackify(convert),
thumbnail: callbackify(thumbnail),
preview: callbackify(preview),
promises: {
convert,
thumbnail,
preview
}
}
async function convert(sourcePath, requestedFormat) {
const width = '600x'
return _convert(sourcePath, requestedFormat, [
'convert',
'-define',
`pdf:fit-page=${width}`,
'-flatten',
'-density',
'300',
`${sourcePath}[0]`
])
}
async function thumbnail(sourcePath) {
const width = '260x'
return convert(sourcePath, 'png', [
'convert',
'-flatten',
'-background',
'white',
'-density',
'300',
'-define',
`pdf:fit-page=${width}`,
`${sourcePath}[0]`,
'-resize',
width
])
}
async function preview(sourcePath) {
const width = '548x'
return convert(sourcePath, 'png', [
'convert',
'-flatten',
'-background',
'white',
'-density',
'300',
'-define',
`pdf:fit-page=${width}`,
`${sourcePath}[0]`,
'-resize',
width
])
}
async function _convert(sourcePath, requestedFormat, command) {
logger.log({ sourcePath, requestedFormat }, 'converting file format')
if (!APPROVED_FORMATS.includes(requestedFormat)) {
throw new ConversionError({
message: 'invalid format requested',
info: { format: requestedFormat }
})
}
const timer = new metrics.Timer('imageConvert')
const destPath = `${sourcePath}.${requestedFormat}`
command.push(destPath)
command = Settings.commands.convertCommandPrefix.concat(command)
try {
await safeExec(command, {
killSignal: KILL_SIGNAL,
timeout: FOURTY_SECONDS
})
} catch (err) {
throw new ConversionError({
message: 'something went wrong converting file',
info: { stderr: err.stderr, sourcePath, requestedFormat, destPath }
}).withCause(err)
}
timer.done()
logger.log(
{ sourcePath, requestedFormat, destPath },
'finished converting file'
)
return destPath
}