Protobuf reorder

[sfc-gh-pchu]

Current issue description:

In this PR: #271. We change the proto definition for PackageInfo which has impact on package list action.
Old definition

message PackageInfo {
  string name = 1;
  string version = 2;
  string repo = 3;
}

New definition

message PackageInfo {
  string name = 1;
  uint32 epoch = 2;
  string version = 3;
  string release = 4;
  string architecture = 5;
  string repo = 6;
}

When the sansshell server is still running with version older than v1.22.0, and sanssh client with version newer or equal to v1.22.0, the server is still returning the old message but the client is expecting the new one which makes following mapping

Server	Client
name	name
version	epoch
repo	version

Then in client, we will format the result and print here

sansshell/services/packages/client/client.go

Line 351 in ae4cd86

for _, pkg := range r.Resp.Packages {

Current issue display

So when running the package list action $./sanssh --targets=localhost packages list, we will see the difference

// wrong result
Installed Packages
                           GeoIP.x86_64.           @base-
                     NessusAgent.x86_64. @sfc_external_software7-
                          PyYAML.x86_64.       installed-
                             acl.x86_64.           @base-
                             apr.x86_64.           @base-
                        apr-util.x86_64.           @base-
// expected result
Installed Packages
                             GeoIP.x86_64     1.5.0-14.el7                            @base
                      NessusAgent.x86_64       10.3.1-es7          @sfc_external_software7
                           PyYAML.x86_64      3.10-11.el7                        installed
                              acl.x86_64    2.2.51-15.el7                            @base
                              apr.x86_64      1.4.8-7.el7                            @base
                         apr-util.x86_64      1.5.2-6.el7                            @base

Resolution:

• reorder the PackageInfo message definition to make them have right mapping

Server	Client
name	name
version	version
repo	repo

• make adjustments to client side formatting to avoid trailing dot or dash
  With older version sansshell, the pkg.Architecture and pkg.Release will be empty, and we shouldn't print trailing . and -.

Output with above situation(newer sanssh + older sansshell)

./sanssh --targets=localhost packages list | tail -n 10
                              yum.noarch 3.4.3-168.el7.centos                        @anaconda
                    yum-langpacks.noarch      0.4.2-7.el7                        @anaconda
             yum-metadata-parser.aarch64     1.1.4-10.el7                        @anaconda
         yum-plugin-fastestmirror.noarch  1.1.31-54.el7_8                        @anaconda
                        yum-utils.noarch  1.1.31-54.el7_8                        @anaconda
                          zenity.aarch64   3.28.1-2.el7_9                         @updates
                             zip.aarch64       3.0-11.el7                        @anaconda
                            zlib.aarch64   1.2.7-21.el7_9                         @updates
                      zlib-devel.aarch64   1.2.7-21.el7_9                         @updates
                            zstd.aarch64      1.4.2-1.el7                            @epel

[sfc-gh-elinardi]

@sfc-gh-pchu could you add some more details of the root cause, and why the fix is effective?
Please also add test cases & results proving that this change actually works in all cases, e.g. new version of client against new version of server, new version of client against old version of server.

[sfc-gh-elinardi]

Looks good to me, but I'd love to get a review from @sfc-gh-srhodes who's more knowledgeable about protobuf.

[sfc-gh-pchu]

Yes, let me request @sfc-gh-srhodes to review.

[sfc-gh-srhodes]

Oof, I missed this mixup. We should get this in as soon as possible.

I highly recommend reading through https://protobuf.dev/programming-guides/dos-donts/ whenever you're figuring out evolution of a proto file.

[sfc-gh-srhodes]

Textprotos aren't very effective for this sort of test (https://protobuf.dev/programming-guides/dos-donts/#dont-use-text-format-messages-for-interchange). If you want to do a compatibility test, the testdata should be the binary proto encoding so that we're testing the on-the-wire format.

A better long-term option is adding a separate lint for protobuf changes, something like https://github.com/nilslice/protolock. We can do that as a separate PR.