meta/lib/oe/rootfs.py: dont' remove any packages by default

Currently, the rootfs.py removes base-passwd, shadow, update-rc.d, update-alternatives and run-postinsts when package-management not in IMAGE_FEATURES, this causes two problems:

1) This makes we can't install the removed pkgs to rootfs, such as IMAGE_INSTALL_append = " shadow", the shadow can't installed (first installed, then removed)

2) The base-passwd has been removed, but the /etc/passwd and /etc/group are still existed since they are generated by preinst, this would confuse the user, and we can't add a postuninst to remove /etc/passwd and /etc/group since they are required when runtime.

I think that we should not remove any pkgs by default, we can add some interfaces/ways to let the user decide whether to remove them or any other pkgs, for example, add a REMOVE_PACKAGS variable, leave it as NULL or only add run-postinsts to it by default.

Hi Robert,

Quoted 13 lines · On Friday 31 July 2015 14:56:15 Robert Yang wrote:

Currently, the rootfs.py removes base-passwd, shadow, update-rc.d, update-alternatives and run-postinsts when package-management not in IMAGE_FEATURES, this causes two problems:

1) This makes we can't install the removed pkgs to rootfs, such as IMAGE_INSTALL_append = " shadow", the shadow can't installed (first installed, then removed)

2) The base-passwd has been removed, but the /etc/passwd and /etc/group are still existed since they are generated by preinst, this would confuse the user, and we can't add a postuninst to remove /etc/passwd and /etc/group since they are required when runtime.

Quoted 4 lines

I think that we should not remove any pkgs by default, we can add some interfaces/ways to let the user decide whether to remove them or any other pkgs, for example, add a REMOVE_PACKAGS variable, leave it as NULL or only add run-postinsts to it by default.

There is a reason for these not to be there by default when you don't have runtime package management - the assumption is you won't be adding or removing any users, thus the binaries that those packages install aren't needed.

Now, it might be argued that if for example you're using some non-package- management based application installation mechanism that has per-application users (Android does this) you will need to add and remove users and therefore you do still need those tools, in which case we would probably need a mechanism for preventing the removal of those packages. I'm not sure whether that would be an IMAGE_FEATURES item (e.g. "user-management"), or perhaps we just make this code get the value of a variable specifying the list of packages to remove instead of it being hardcoded as it is now. Either way though I think the default behaviour does make sense for most people and I don't think we ought to be changing that part.

Cheers,
Paul

Quoted 4 lines

I think that we should not remove any pkgs by default, we can add some interfaces/ways to let the user decide whether to remove them or any other pkgs, for example, add a REMOVE_PACKAGS variable, leave it as NULL or only add run-postinsts to it by default.

There is a reason for these not to be there by default when you don't have runtime package management - the assumption is you won't be adding or removing any users, thus the binaries that those packages install aren't needed.

On Fri, Jul 31, 2015 at 12:46 PM, Paul Eggleton

Quoted 5 lines · <[email protected]> wrote:

Quoted 4 lines

I think that we should not remove any pkgs by default, we can add some interfaces/ways to let the user decide whether to remove them or any other pkgs, for example, add a REMOVE_PACKAGS variable, leave it as NULL or only add run-postinsts to it by default.

Quoted 4 lines

There is a reason for these not to be there by default when you don't have runtime package management - the assumption is you won't be adding or removing any users, thus the binaries that those packages install aren't needed.

I am not sure to understand the relationship between runtime package management, and adding/removing users? Why would no runtime package management, imply no need to add/remove users?

Quoted 3 lines

I am not sure to understand the relationship between runtime package management, and adding/removing users? Why would no runtime package management, imply no need to add/remove users?

I guess the underlying assumption is that if you have no package manager, in a typical embedded context (if there is such a thing) that implies you won't be changing the system after setup.

Hi Robert,

Quoted 13 lines · On Friday 31 July 2015 14:56:15 Robert Yang wrote:

Currently, the rootfs.py removes base-passwd, shadow, update-rc.d, update-alternatives and run-postinsts when package-management not in IMAGE_FEATURES, this causes two problems:

1) This makes we can't install the removed pkgs to rootfs, such as IMAGE_INSTALL_append = " shadow", the shadow can't installed (first installed, then removed)

2) The base-passwd has been removed, but the /etc/passwd and /etc/group are still existed since they are generated by preinst, this would confuse the user, and we can't add a postuninst to remove /etc/passwd and /etc/group since they are required when runtime.

Quoted 4 lines

I think that we should not remove any pkgs by default, we can add some interfaces/ways to let the user decide whether to remove them or any other pkgs, for example, add a REMOVE_PACKAGS variable, leave it as NULL or only add run-postinsts to it by default.

There is a reason for these not to be there by default when you don't have runtime package management - the assumption is you won't be adding or removing any users, thus the binaries that those packages install aren't needed.

Now, it might be argued that if for example you're using some non-package- management based application installation mechanism that has per-application users (Android does this) you will need to add and remove users and therefore you do still need those tools, in which case we would probably need a mechanism for preventing the removal of those packages. I'm not sure whether that would be an IMAGE_FEATURES item (e.g. "user-management"), or perhaps we just make this code get the value of a variable specifying the list of packages to remove instead of it being hardcoded as it is now. Either way

though I think the default behaviour does make sense for most people and I don't think we ought to be changing that part.

Cheers,
Paul

Quoted 29 lines · Paul Eggleton

Hi Robert,

Quoted 16 lines · On Friday 31 July 2015 14:56:15 Robert Yang wrote:

Currently, the rootfs.py removes base-passwd, shadow, update-rc.d, update-alternatives and run-postinsts when package-management not in IMAGE_FEATURES, this causes two problems:

1) This makes we can't install the removed pkgs to rootfs, such as

IMAGE_INSTALL_append = " shadow", the shadow can't installed (first installed, then removed)

2) The base-passwd has been removed, but the /etc/passwd and /etc/group

are still existed since they are generated by preinst, this would confuse the user, and we can't add a postuninst to remove /etc/passwd
and /etc/group since they are required when runtime.

Quoted 4 lines

I think that we should not remove any pkgs by default, we can add some interfaces/ways to let the user decide whether to remove them or any other pkgs, for example, add a REMOVE_PACKAGS variable, leave it as NULL or only add run-postinsts to it by default.

There is a reason for these not to be there by default when you don't have runtime package management - the assumption is you won't be adding or removing any users, thus the binaries that those packages install aren't needed.

Quoted 9 lines

Now, it might be argued that if for example you're using some non-package- management based application installation mechanism that has per-application users (Android does this) you will need to add and remove users and therefore you do still need those tools, in which case we would probably need a mechanism for preventing the removal of those packages. I'm not sure whether that would be an IMAGE_FEATURES item (e.g. "user-management"), or perhaps we just make this code get the value of a variable specifying the list of packages to remove instead of it being hardcoded as it is now. Either way

I prefer use a variable like REMOVE_PACKAGS to remove them, but after more thinking, it seems that we need something like user-management since the removing only be enabled when package-management/user-management is not in IMAGE_FEATURES.

On the other side, use IMAGE_FEATURES like user-management may also cause confusion to the user, when people does things like:

IMAGE_INSTALL_append += "shadow"

He wants to use the command like "useradd", but sorry, the "user-management" is not in IMAGE_FEATURES, so he can't get the command "useradd". Usually linux users know that the package like shadow provides the command "useradd", but only OE developers/users(or advanced developer/users) know that he also needs user-management in IMAGE_FEATURES, this seems not a good user experience.

The similar to rpm/package-management, when we install rpm package in the image, usually, we'd like to use command like "rpm -qa/ql", but it doesn't work when package-management is not in the IMAGE_FEATURES, we've received a few questions/complains about this.

I think that OE is a development platform, we'd better avoid such policies for the end user, we don't remove anything for them in the fundamental code like rootfs.py by default, and leave interfaces for them to remove when they want.