Export of Application

apaeffgen

All exported Applications are 0 bytes.
Error message from the console:
2025-08-27 09:11:02 server could not finish module export, stat data/transfer/79d4db46-0f11-47fa-a00b-257d24ddbb48.json: no such file or directory
Any hints whats going wrong? All export checks are green

gabriel

apaeffgen Can it be a firewall issue? Or is opening port 443 sufficient?

Port 443 is enough as long as websocket connections are not terminated, though this is usually a proxy issue.

Before, you mentioned this error:

apaeffgen 2025-08-27 09:11:02 server could not finish module export, stat data/transfer/79d4db46-0f11-47fa-a00b-257d24ddbb48.json: no such file or directory

This would explain the 0 byte issue und usually occurs due to badly configured permissions or paths. Even if you fixed the permission/path issues, the missing transfer files would need to be recreated. It´s no big deal to do this and then the issue goes away.

If you no longer get any error in the admin panel, then it´s something outside of r3. Either a proxy (many firewalls nowadays have proxy features enabled by default) or something in your browser. Without knowing more about your infrastructure, I can only speculate.

If you are part of an organization, we can also offer remote service and have a look together. Finding the issue is usually quite quick.

gabriel

When you install any app in r3 from file or from the repository, its export file is stored in r3´s transfer directory for future exports.

When you then want to export your own application, when it has dependencies on other installed apps, the transfer directory is checked. If the export files does not exist for the app that yours depends on, the export fails.

I´ve seen this error multiple times in Docker setups, where admins did not make these folders persistent and kept recreating them. If you do not use Docker, this is unlikely. Please check if the transfer path is there and writable for the user running the r3 service.

Btw. the ID 79d4db46-0f11-47fa-a00b-257d24ddbb48 belongs to the app lsw_shared - which your app apparently is built on, so its looking for the corresponding export file.

gabriel

gabriel Please check if the transfer path is there and writable for the user running the r3 service.

You need to check this first, before we can continue. The path must be there, must be writable for the service and must contain multiple files - 1 for every installed app. If any of those are wrong, exporting is not possible.

For reference of all required paths, you can look at the backup chapter of the documentation. Where those paths are, depends on your config.json file. There is another path for temporary files - but it´s not named in the backup chapter as its not relevent for backups. It also must be writable.

If the service does not have write access to any of these (including the config.json file), r3 will not work correctly.

apaeffgen

I do not use docker, but AlmaLinux.
If i try to export a related app, like organisations (lsw_organisations_190) i get the same error. The browser is asking for a path to export. Is there a temp folder to make rightable?

Anything else what could cause this problem?

apaeffgen

gabriel
i checked all above. Still a zero byte export of a standard app like company.
The only error i get in /var/log/messages is:
r3[13468]: 2025/08/29 20:28:56 http: TLS handshake error from [::1]:58148: remote error: tls: unknown certificate
Also in the transfer directory, that is writable, there are json files that do not correspond to the app-id-numbers from the webgui of r3
Any further suggestions?

apaeffgen

I do not know, if this is related, but the backup function works as expected.
What kind of file .rei3 will be? will it contain the same files as the backup directory?
How to manualy pack an app for reimport. Or is it possible to transfer the backup to a production machine?

gabriel

apaeffgen
Backups and application exports are different things.

A backup is a copy of a r3 instance. It includes the database, uploaded files, and so on. With backups you can recover your r3 instance to another system, keeping all your installed applications & data. For a guide on how to do that, you can check here.

An application export stores the structure of a single r3 application as JSON file, together with all r3 applications that the app is dependent on, compressed as a zip file (with *.rei3 extension). The JSON files for all dependencies are stored in the transfer directory.

Application exports serve to transfer an application version to another r3 instance. Usually to install or upgrade the target version of the application. It does not contain any data, besides preset records. The same r3 export can be used to rollout new versions on many r3 instances, regardless of what data is stored there - it´s just the application structure.

What are you trying to do? Are you trying to move your r3 instance / test recovery? Or are you trying to export a version of your r3 application?

apaeffgen

gabriel
I have a development system and want to transfer the application to a production system.
So every change is programmed and tested in the development system. Then i want to export the changes without any data to the production system, without loosing production data.

It gets tricky, when the data model gets enhanced. Maybe you have a good suggestion for that?

But for now, the export does not work. Without an error message i am lost, why it gets 0 byte. The transfer directory is writable and consists of json files.

gabriel

apaeffgen So every change is programmed and tested in the development system. Then i want to export the changes without any data to the production system, without loosing production data.

That is definitely best practice and what we recommend in most scenarios.

apaeffgen It gets tricky, when the data model gets enhanced. Maybe you have a good suggestion for that?

Renaming or creating things is not a problem, but adding not-nullable attributes without a default is not allowed when there are records already. The same with adding a not-null constraints on attributes that have null data in the target instance - the database just won´t have it and it´s right to do so. But there are solutions for these situations. If you encounter one, please go into some details and we can help. There are a few exotic issues that can occur with complex function call chains, but nothing we have not found a good solution for yet.

apaeffgen But for now, the export does not work. Without an error message i am lost, why it gets 0 byte.

There are basically two places where an error can occur during export. If r3 runs into an error, like you had before with the missing transfer files, than it logs it into the system log. Should this error still occur, we need to recreate those transfer files.

Here is a case, where somebody had an issue due to a key pair being invalid during export - he also got a 0 bytes file:
https://community.rei3.de/d/325-exported-application-file-is-empty/2

If there is no error in the admin panel at all after an export failed with 0 bytes, then the other potential error source is a proxy. We sometimes had issues with proxies not allowing downloads. These issues sometimes came in combination with header limitations for HTTP requests or with issues due to invalid SSL certs.

apaeffgen

Can it be a firewall issue? Or is opening port 443 sufficient?
I will investigate further, maybe i missed something.

apaeffgen

I tested the export in my development environment (newly set up), and there the export works.
Maybe i messed up with my first installation, because it showed strange behaviour, after i played with some parameters (Like renaming apps, changing dependancies.....

I will post some information, if i found the root cause.

gabriel

apaeffgen I will post some information, if i found the root cause.

Appreciated. :)

There cannot be that many issues as r3 has very few dependencies and there is little variation in how you can run it.

I hope you find the cause soon.

apaeffgen

gabriel

I could now export everything with no error from my test system. But when i want to reimport the exported files, i get an error message:

"could not finish module import, could not decode PEM block from public key"
What i did:

I created a 2024 key pair. Used this keypair to export the application.
Then i copied the public key to my productive system and created a new Key in the admin key area.
Then i imported the file into my productive system

Anything i missed here?

gabriel

apaeffgen Then i copied the public key to my productive system and created a new Key in the admin key area.

Did you save after importing they key? You can check be seeing if the key is gone after re-opening the admin panel.

I ask because this is a common error. :)

apaeffgen

I saved one 2048 public key in both systems, just to make sure. Also the temp private key is the only one i generated in the exporting system. But the bom error message persists:

Message from transferlog:
" 03.09.2025 15:10:32
Fehler
node1 - Server could not finish module import, could not decode PEM block from public key
03.09.2025 15:10:32
Info
node1 - Transfer import is parsing 2 module files"

apaeffgen

What i checked in the exported .rei3 file, the signature in the end of the .json file is not the key i used to export the application. Is this a hint for something?

Also the exported file is not encrypted. It can be read with plain text editors and can be unzipped without a problem.

So no hint to any RSA Key whatsoever. Only the signature section in the json files. Any problem with the coding / decoding?

gabriel

apaeffgen What i checked in the exported .rei3 file, the signature in the end of the .json file is not the key i used to export the application. Is this a hint for something?

It sounds like there are some misunderstandings.

If the error "could not decode PEM block from public key" comes up, it means that the public key was entered wrongly. This is how it should look like:

If your key was entered without the -----BEGIN RSA PUBLIC KEY----- line, or is incomplete, you will get this error.

Next topic: Exporting apps
Export files are not encrypted, they are signed. There is nothing secretive in there; the signature only serves to guarantee that the author is who he/she claims to be. If the corresponding public key from the author is not imported into the target system, imports will be denied. Exporting itself happens via the private key of the author of the app.

apaeffgen

I found the problem of the PEM - Error.
I work on MacOS and saved the keys to a texteditor (COT in this case). If i copy the key from this textfile into the browser window, some hidden charakters break the RSA-Decoding.

Maybe a hidden Line End, a BOM segment or other. If i copy the RSA- Key (Just text) from browser to browser it works.

Same on a Linux System. Did not test on windows.
Maybe this coding / decoding process could be handled more robust? I like to make copys of important files for later. Even if i have then to encrypt them.

This just for people, who have the same problem

gabriel

This is weird. We regularly work with Linux and I know people that build apps on MacOS - but I have not heard of these kinds of issues yet.

Could you maybe share your problematic public key file? Then I can run tests on it and see if I can reproduce the error. If you do not want to share your current public key, you can create a new one. If what you write is the case, this error should always happen.