node.js - Cloud Functions for Firebase - Converting PDF to image -

cloud functions firebase has nice sample create thumbnail each uploaded image. done making use of imagemagick.

i tried convert sample convert pdfs images. imagemagick can do, can't make work cloud functions firebase. keep getting code 1 error:

childprocesserror: `convert /tmp/cd9d0278-16b2-42be-aa3d-45b5adf89332.pdf[0] -density 200 /tmp/cd9d0278-16b2-42be-aa3d-45b5adf89332.pdf` failed code 1     @ childprocess.<anonymous> (/user_code/node_modules/child-process-promise/lib/index.js:132:23)     @ emittwo (events.js:106:13)     @ childprocess.emit (events.js:191:7)     @ maybeclose (internal/child_process.js:877:16)     @ socket.<anonymous> (internal/child_process.js:334:11)     @ emitone (events.js:96:13)     @ socket.emit (events.js:188:7)     @ pipe._handle.close [as _onclose] (net.js:498:12) 

of course 1 possibility converting pdfs not supported.

const functions = require('firebase-functions'); const gcs = require('@google-cloud/storage')(); const spawn = require('child-process-promise').spawn; // [end import]  // [start generatethumbnail] /**  * when image uploaded in storage bucket generate thumbnail automatically using  * imagemagick.  */ // [start generatethumbnailtrigger] exports.generatethumbnail = functions.storage.object().onchange(event => { // [end generatethumbnailtrigger]     // [start eventattributes]     const object = event.data; // storage object.      const filebucket = object.bucket; // storage bucket contains file.     const filepath = object.name; // file path in bucket.     const contenttype = object.contenttype; // file content type.     const resourcestate = object.resourcestate; // resourcestate 'exists' or 'not_exists' (for file/folder deletions).     // [end eventattributes]      // [start stopconditions]     // exit if triggered on file not image.     if (!contenttype.startswith('application/pdf')) {         console.log('this not pdf.');         return;     }      // file name.     const filename = filepath.split('/').pop();     // exit if image thumbnail.     if (filename.startswith('thumb_')) {         console.log('already thumbnail.');         return;     }      // exit if move or deletion event.     if (resourcestate === 'not_exists') {         console.log('this deletion event.');         return;     }     // [end stopconditions]      // [start thumbnailgeneration]     // download file bucket.     const bucket = gcs.bucket(filebucket);     const tempfilepath = `/tmp/${filename}`;     return bucket.file(filepath).download({         destination: tempfilepath     }).then(() => {         console.log('pdf downloaded locally to', tempfilepath);         // generate thumbnail of first page using imagemagick.         return spawn('convert', [tempfilepath+'[0]' ,'-density', '200', tempfilepath]).then(() => {             console.log('thumbnail created at', tempfilepath);             // convert pdf extension png             const thumbfilepath = filepath.replace('.pdf', 'png');             // uploading thumbnail.             return bucket.upload(tempfilepath, {                 destination: thumbfilepath             });         });     });     // [end thumbnailgeneration] });