firebase 云函数 onFinalize 触发器没有预定义的存储桶？

Question

Is it possible to write a firebase cloud function that triggers when a new fila was created in firebase storage - onFinalize (but we don't know the exact bucket in advance) ?

Inside my firebase storage a have a folder 'loads' and inside I have folders named with load id like:

• /loads/-Lw1UySdunYyFMrrV6tl
• /loads/-LwisA5hkNl_uxw3k36f
• /loads/-LwkPUm-q7wNv-wZ49Un

https://ibb.co/NnQkTyC here's a screenshot of storage

I want to trigger cloud function when new file has been created inside one of these folders. I don't know in andvance where the file will be created. I don't know if this is even possible. That's why I need an advice.

My main goal is to merge 2 pdf files in one within cloud functions. In my app (TMS written with vuejs) on frontend I create confirmationOrder.pdf using html2canvas/jsPDF and then save it to storage/loads/${loadID}. And later on user can manually upload POD.pdf on the same bucket. When it happens I want my cloud function to merge these two pdfs in one new file (in same storage bucket). But again I don't know the bucket in advance.

Here's how I upload PDFs in frontend:

 async uploadConfPDF({ commit }, payload) {
      const PDF = payload.PDF;
      const loadID = payload.loadID;
      const fileName = payload.fileName;

      const fileData = await firebase
        .storage()
        .ref(`loads/${loadID}/${fileName}.pdf`)
        .put(PDF);

      const confOrderURL = await fileData.ref.getDownloadURL();

      return confOrderURL;
    }, 

Any help is highly appreciated. Sorry if my explanation could seem not clear enough. English is not my native language.

Answer 1

EDIT FOLLOWING YOUR QUESTION RE-WORKING

Based on your code and on the print screen of your Cloud Storage console, you are working in the default bucket of your project, which location's URL is gs://alex-logistics.appspot.com .

As we can see on the print screen of your Cloud Storage console, the files in your bucket are presented in a hierarchical structure , just like the file system on your local hard disk. However, this is just a way of presenting the files: there aren't genuine folders/directories in a bucket, the Cloud Storage console just uses the different part of the files paths to "simulate" a folder structure.

---

So, based on the above paragraphs, I think that your question can be re-phrased to " In a Cloud Function, how can I extract the different parts of the path of a file that is uploaded to the default bucket of my Firebase Project? ".

Answer:

In a Cloud Function that is triggered when a file is added to the default bucket, you can get the file path as follows:

exports.yourCloudFunction = functions.storage.object().onFinalize(async (object) => {

    const filePath = object.name; // File path in the bucket.

    //...

});

Since we use an onFinalize event handler, you get the path of this new file by using the name property of the object Object, which is of type ObjectMetadata .

You can then use some String methods to, for example, extract from this path the ${loadID} you refer to in your question.