fix: normalize nil group param to prevent NoMethodError in version view

[Copilot]

Requesting /node/version/view?node=<node>&num=1 without group= can raise NoMethodError: undefined method '+' for nil from version.haml because the route passes params[:group] through as nil and the template concatenates it as a string. The same nil-path exists in /node/version/diffs; assigning groups to all devices avoids the crash, but only as a workaround.

• Bug

  • params[:group] is nil when the query omits group=.
  • The version/diffs views assume @info[:group] is string-like and build group/node paths from it.
  • Repro:

    curl "http://<oxidized>:8888/node/version/view?node=<node>&num=1"
    # => HTTP 500

• Change

  • Normalize params[:group] to '' in both route handlers:
    • GET /node/version/view
    • GET /node/version/diffs
  • This keeps the existing template guards working for “no group” requests without changing grouped behavior.

• Code

  • Applied in webapp.rb:

    @info = {
      node: node,
      group: params[:group] || '',
      oid: params[:oid],
      time: Time.at(params[:epoch].to_i),
      num: params[:num]
    }

• Coverage

  • Add focused route specs for requests that omit group= entirely, covering both version view and diffs paths.
  • Document the user-visible fix in CHANGELOG.md.

Original prompt

Open a pull request from the branch fix/nil-group-param-nomethoderror in makaiver/oxidized-web to ytti/oxidized-web:master.

The PR should:

• Title: "fix: normalize nil group param to prevent NoMethodError in version view"
• Description explaining:
  • The bug: requesting /node/version/view?node=<node>&num=1 without a group= parameter causes NoMethodError: undefined method '+' for nil in the version.haml template (line 5), because params[:group] returns nil and the template tries to concatenate it with a string.
  • The fix: normalize params[:group] to '' when absent using || '' in both the /node/version/view and /node/version/diffs route handlers in webapp.rb.
  • Reproduction: curl http://<oxidized>:8888/node/version/view?node=<node>&num=1 (no group param) → HTTP 500
  • No groups workaround: assigning groups to all devices avoids the bug but is not a proper fix.

The following is the prior conversation context from the user's chat exploration (may be truncated):

User: ```
2026-05-27 07:58:09.981319 E [11:SemanticLogger::Appenders] SemanticLogger::Appenders -- Failed to log to appender: SemanticLogger::Appender::File -- Exception: ArgumentError: The supplied log file_name: /home/oxidized/.config/oxidized/logs is already a directory.
/var/lib/gems/3.3.0/gems/semantic_logger-4.18.0/lib/semantic_logger/appender/file.rb:158:in reopen' /var/lib/gems/3.3.0/gems/semantic_logger-4.18.0/lib/semantic_logger/appender/file.rb:185:in log'
/var/lib/gems/3.3.0/gems/semantic_logger-4.18.0/lib/semantic_logger/appenders.rb:32:in `block in log'
/var/lib/gems/3.3.0/gems/semantic_logger-4.18.0/lib/semantic_logger/appenders.rb:31:in `each'
/var/lib/gems/3.3.0/gems/semantic_logger-4.18.0/lib/semantic_logger/appenders.rb:31:in `log'
/var/lib/gems/3.3.0/gems/semantic_logger-4.18.0/lib/semantic_logger/appender/async.rb:151:in `process_messages'
/var/lib/gems/3.3.0/gems/semantic_logger-4.18.0/lib/semantic_logger/appender/async.rb:120:in `process'
/var/lib/gems/3.3.0/gems/semantic_logger-4.18.0/lib/semantic_logger/appender/async.rb:76:in `block in thread'
2026-05-27 07:58:09.982027 E [11:SemanticLogger::Appenders] SemanticLogger::Appenders -- Failed to log to appender: SemanticLogger::Appender::File -- Exception: ArgumentError: The supplied log file_name: /home/oxidized/.config/oxidized/logs is already a directory.
/var/lib/gems/3.3.0/gems/semantic_logger-4.18.0/lib/semantic_logger/appender/file.rb:158:in `reopen'
/var/lib/gems/3.3.0/gems/semantic_logger-4.18.0/lib/semantic_logger/appender/file.rb:185:in `log'
/var/lib/gems/3.3.0/gems/semantic_logger-4.18.0/lib/semantic_logger/appenders.rb:32:in `block in log'
/var/lib/gems/3.3.0/gems/semantic_logger-4.18.0/lib/semantic_logger/appenders.rb:31:in `each'
/var/lib/gems/3.3.0/gems/semantic_logger-4.18.0/lib/semantic_logger/appenders.rb:31:in `log'
/var/lib/gems/3.3.0/gems/semantic_logger-4.18.0/lib/semantic_logger/appender/async.rb:151:in `process_messages'
/var/lib/gems/3.3.0/gems/semantic_logger-4.18.0/lib/semantic_logger/appender/async.rb:120:in `process'
/var/lib/gems/3.3.0/gems/semantic_logger-4.18.0/lib/semantic_logger/appender/async.rb:76:in `block in thread'
2026-05-27 07:58:09.983073 E [11:SemanticLogger::Appenders] SemanticLogger::Appenders -- Failed to log to appender: SemanticLogger::Appender::File -- Exception: ArgumentError: The supplied log file_name: /home/oxidized/.config/oxidized/logs is already a directory.
/var/lib/gems/3.3.0/gems/semantic_logger-4.18.0/lib/semantic_logger/appender/file.rb:158:in `reopen'
/var/lib/gems/3.3.0/gems/semantic_logger-4.18.0/lib/semantic_logger/appender/file.rb:185:in `log'
/var/lib/gems/3.3.0/gems/semantic_logger-4.18.0/lib/semantic_logger/appenders.rb:32:in `block in log'
/var/lib/gems/3.3.0/gems/semantic_logger-4.18.0/lib/semantic_logger/appenders.rb:31:in `each'
/var/lib/gems/3.3.0/gems/semantic_logger-4.18.0/lib/semantic_logger/appenders.rb:31:in `log'
/var/lib/gems/3.3.0/gems/semantic_logger-4.18.0/lib/semantic_logger/appender/async.rb:151:in `process_messages'
/var/lib/gems/3.3.0/gems/semantic_logger-4.18.0/lib/semantic_logger/appender/async.rb:120:in `process'
/var/lib/gems/3.3.0/gems/semantic_logger-4.18.0/lib/semantic_logger/appender/async.rb:76:in `block in thread'
2026-05-27 07:58:10.143687 E [11:SemanticLogger::Appenders] SemanticLogger::Appenders -- Failed to log to appender: SemanticLogger::Appender::File -- Exception: ArgumentError: The supplied log file_name: /home/oxidized/.config/oxidized/logs is already a directory.
/var/lib/gems/3.3.0/gems/semantic_logger-4.18.0/lib/semantic_logger/appender/file.rb:158:in `reopen'
/var/lib/gems/3.3.0/gems/semantic_logger-4.18.0/lib/semantic_logger/appender/file.rb:185:in `log'
/var/lib/gems/3.3.0/gems/semantic_logger-4.18.0/lib/semantic_logger/appenders.rb:32:in `block in log'
/var/lib/gems/3.3.0/gems/semantic_logger-4.18.0/lib/semantic_logger/appenders.rb:31:in `each'
/var/lib/gems/3.3.0/gems/semantic_logger-4.18.0/li...

This pull request was created from Copilot chat.