Sequential number generators stored in a fixed-size format eventually run
out of values. But activity queues only care about what activities are
currently present: any uid can be reused as soon as it is available.
So stop using a sequential id generator for activity uids, and instead use
random values.

Vincent Pelletier:
- Commit message.
- Minor formatting changes.
- Do probability computations, and increase activity uid storage size to
  64bits integers, up from 32. Table schema migration happens on first
  activity node which starts on upgraded code.
- Apply to SQLJobLib too.

Duplicate message detection is not good enough: different messages with
the same unicity value may bear different serialization_tags. This code
does not takes this into account, which can lead to deleting such tagged
message and validate an untagged one, which breaks serialization_tag
contract of preventing any further activity validation until execution
of all such-tagged validated activities is successful.
Also, it is not validation's node job to deduplicate: it can happen during
message execution without slowing down this crucial (performance-wise)
activity node.
As a result, distribute methods of SQLDict and SQLQueue can be factorised.

0. Download codemirror tarball ('lib/codemirror.js' is not available in git repository anymore):
   wget http://codemirror.net/codemirror.zip && unzip codemirror.zip

1. Prepare files to upload:
   cd UNZIPPED_CODEMIRROR_DIRECTORY/
   rm -r bin/ doc/ index.html demo/ src/ test/ rollup.config.js package.json mode/*/index.html mode/index.html .[a-z]*
   # 54087b03
   mv addon/edit/ addon/cm_edit/ && find -type f | xargs sed -i 's#addon/edit/#addon/cm_edit/#g'
   # https://github.com/codemirror/CodeMirror/issues/5321
   sed -i '/"Ctrl-V"/d' keymap/emacs.js

2. Edit zope.conf to enable FTP access:
   <ftp-server>
    address localhost:2202
   </ftp-server>

3. Upload files to Zope:
   yafc ftp://zope:zope@localhost:2202/erp5/portal_skins/erp5_code_mirror/codemirror/
   yafc> rm -r *
   yafc> put -r *

4. Run portal_alarms/Alarm_checkSkinCacheActive?fixit:int=1

- requests to bootstrap and site availability urls using a script run with userhosts
- hardcoded parameters removed
- try-exception controls in communication with master
- general refactoring and cleanup

ZODB Components not following ID=(document|extension|test).VERSION.REFERENCE convention are not importable anymore.

Import mechanism now relies on this convention to find the document in
portal_components.

This is necessary to get rid of _registry_dict (ZODB Components equivalent of
document_class_registry), along with several locks. This used to be a mapping
between (reference, version) to ID stored outside of Zope Transactions as a
dict on global erp5.component.XXX modules.

This did not work for long transactions such as installing many bt5s:
  1. Transaction1: Install a bt5 with ZODB Component "Foo".
     => Trigger a reset and _registry_dict is cleared.
  2. Transaction2: TimerServer kicks in.
     => Generate _registry_dict without "Foo".
  3. Transaction1: Install another bt5 using "Foo".
     => "Foo" not in _registry_dict and thus considered not present.

/reviewed-on !613

- test duration is get from testsuite definition
- refactoring and cleanup in runScalabilityTestSuite and benchmark
- request timeout in metric thread

/reviewed-on !607

Document why this method tolerates unhandled method types.

workflow_history attribute may not exist on bootstrapping (constructInstance),
which leads AttributeError exception, which could have further side-effects
as this is called during dynamic class initialisation.
Also, original code from CMFCore.WorkflowTool, from which this code is
derived for bootstrap reasons, catches KeyError (when history exists,
just not for considered workflow), so follow the same pattern.
Laslty, also catch IndexError in case the workflow history entry would
exist empty - which would be the sign of a broken workflow history.

workflow_history attribute may not exist on bootstrapping (constructInstance),
which could lead to acquisition, which could have further side-effects
as this is called during dynamic class initialisation.
Also, original code from CMFCore.WorkflowTool, from which this code is
derived for bootstrap reasons, does the equivalent aq_base, so follow
the same pattern.

LIMIT hides duplicates. We want to know if we ever violate the
soft-constraint of path unicity in catalog, so stop setting a LIMIT.
Also, for uid lookup, LIMIT is meaningless as this is ha hard unicity
constraint (must be enforced by relational database for ERP5 to work).

Also, simplify both the DTML and the SQL by having fewer ways to be
invoked (backward-compatible).

When _reindexObjectList receives a document more than once (which may
happen when multiple different-tag indexation activities are spawned for
the same document), it would emit a meaningless error, saying that
document /foo/bar stole the uid of document /foo/bar.
Instead, fix duplicate tracking and skip such dulicates.

Also, simplify & make _reindexObjectList more robust:
- Always check path length.
- Allocate uids before looking for duplicates in catalog (it may not be
  actually needed at this level nowadays).
- Always check both uid-to-path and path-to-uid mappings.
- Reuse existing mappings to detect duplicates among objects being reindexed,
  removing the need for assigned_uid_dict.
- Avoid computing path more than once, as it's expensive.

ZSQLCatalog now requires having portal_ids.
Keep support for clearing existing ones.

Any existing "reserved" row encountered while indexing documents will be
treated as a uid being attributed to more than one path.

See nexedi/erp5@78356c43

TypeError: isinstance() arg 2 must be a class, type, or tuple of classes and types

- bug fixing while getting instance_guid
- minotr refactoring in request parameters