Add a custom_process_id parameter for use with lambda

[genehand]

I found that using this with a lambda function ended up with the same hostname & PID (inside the containers) for multiple runs. This adds the option to specify a custom_process_id, for example I'm using the context.aws_request_id.

Had to do a little extra to keep rubocop happy :)

[genehand]

Looks like there's a new bundler 2.0 issue with Travis: https://docs.travis-ci.com/user/languages/ruby/#bundler-20

[eredi93]

why do we need this? we only instantiate the class once at line 14 let(:store) { described_class.new(table, hash_key, options) } i don't understand why we need to use allow_any_instance_of

[genehand]

When calling host_process_id from initialize, here's what I get without it:

  1) Marloss::Store.create_lock should create the lock
     Failure/Error:
       client.put_item(
         table_name: table,
         item: {
           hash_key => name,
           "ProcessID" => process_id,
           expires_key => (Time.now + ttl).to_i
         },
         expression_attribute_names: {
           "#E" => expires_key,
           "#P" => "ProcessID"

       #<InstanceDouble(Aws::DynamoDB::Client) (anonymous)> received :put_item with unexpected arguments
         expected: ({:condition_expression=>"attribute_not_exists(LockID) OR #E < :now OR #P = :process_id", :expression_...>1549560099, "LockID"=>"my_resource", "ProcessID"=>"hostname.local:86776"}, :table_name=>"my_table"})
              got: ({:condition_expression=>"attribute_not_exists(LockID) OR #E < :now OR #P = :process_id", :expression_...=>1549560099, "LockID"=>"my_resource", "ProcessID"=>"doxbook.local:86776"}, :table_name=>"my_table"})
       Diff:

       @@ -2,10 +2,10 @@
           "attribute_not_exists(LockID) OR #E < :now OR #P = :process_id",
          :expression_attribute_names=>{"#E"=>"Expires", "#P"=>"ProcessID"},
          :expression_attribute_values=>
       -   {":now"=>1549560089, ":process_id"=>"hostname.local:86776"},
       +   {":now"=>1549560089, ":process_id"=>"doxbook.local:86776"},
          :item=>
           {"Expires"=>1549560099,
            "LockID"=>"my_resource",
       -    "ProcessID"=>"hostname.local:86776"},
       +    "ProcessID"=>"doxbook.local:86776"},
          :table_name=>"my_table"}]

[genehand]

Had a more experienced rubyist take a look.. when you do allow(store) that calls the let(:store), that instantiates the object but at that point the stub method hasn't been created because it's evaluating the store value to pass to allow()

[eredi93]

gotcha. i pulled down the fork and ran it myself and yes is true, because we now call host_process_id at initialisation the system call get executed before the stubbing. makes sense now 👍
i just think allow_instance_of tend to make specs flaky and cause side effect - i like to avoid using it when possible but in this case is 🆗
thanks for trying this out 🙇

[eredi93]

@genehand i merged #14 and updated the the ruby versions is Travis. my build was 🍏 can you try rebasing? the bundler error should now be gone 😄

the PR overall looks good happy to merge this in once is 🍏

[genehand]

Awesome, travis isn't starting up so I'm going to try closing & reopening

[genehand]

Hmm, can you kick travis off? Or should I open a new PR?

[eredi93]

@genehand you need to rebase your repo
as you can see https://github.com/genehand/marloss/blob/master/.travis.yml you still the old trevis file
unfortunately i cannot rebase this PR as i do not have write access to your fork

you would need to rebase like this:

$ git remote add eredi93 git@github.com:eredi93/marloss.git
$ git remote show
eredi93
origin
$ git checkout unique-process-id
$ git pull eredi93 master
$ git rebase eredi93/master
$ git push -f

this should do the trick 😄

[genehand]

Hmm, already rebased. You can see the force-push up above and the updated .travis.yml in the branch I opened this from: https://github.com/genehand/marloss/blob/unique-process-id/.travis.yml

Not sure what's up with travis 🤷‍♂️ I'll try with a new PR