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GenNode: investigate Problem with non-unique attribute IDs

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this is not a problem, strictly sepaking, locally.
But it becomes a problem once the GUI uses those attribute IDs
as Element-IDs for tangible UI entities, which need to be uniquely
addressable via the UI-Bus.

An obvious solution is to inject randomness into the Attribute ID hash
This commit is contained in:
Fischlurch 2018-11-09 20:19:45 +01:00
parent 20451c958a
commit 83394a6f01
3 changed files with 193 additions and 16 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

28
src/lib/diff/gen-node.hpp
View file

@ -52,6 +52,16 @@
** addressable by-name and an (ordered) collection of elements treated
** as children within the scope of the given record.
**
** ## The GenNode ID
**
** Each GenNode holds an ID tag, allowing to establish _identical_ and _distinct_
** elements within a scope. This ID is based on lib::idi::BareEntryID, thereby
** providing a human readable symbolic part, and a hash value. By default, these
** GenNode IDs are fabricated such as to hold a non-reproducible, random hash
** value -- however, there are construction flavours allowing to pass in an
** pre-existing distinct Entry-ID.
**
**
** # Requirements
**
** GenNode elements are to be used in the diff detection and implementation.
@ -66,7 +76,7 @@
** typed context, either based on some kind of embedded type tag, or
** alternatively by visitation and matching
** - finally, the handling of changes prompts us to support installation
** of a specifically typed <i>change handling closure</i>.
** of a specifically typed _change handling closure_.
**
** ## monadic nature?
**
@ -223,6 +233,10 @@ namespace diff{
idi::getTypeHash<X>())
{ }
ID (string const& symbolicID, HashVal seed)
: idi::BareEntryID (symbolicID, seed)
{ }
public:
explicit
ID (GenNode const& node)
@ -433,7 +447,15 @@ namespace diff{
}
};
template<typename X>
static GenNode
forAttribute (string const& key, X&& payload)
{
return GenNode{ID(key, std::rand()) // NOTE: random hash seed
,DataCap(forward<X> (payload))};
}
protected:
/** @internal for dedicated builder subclasses */
GenNode (ID&& id, DataCap&& d)
@ -845,7 +867,7 @@ namespace diff{
inline GenNode
Rec::buildAttribute (string const& key, X&& payload)
{
return GenNode(key, std::forward<X>(payload));
return GenNode::forAttribute (key, forward<X>(payload));
}

13
src/lib/diff/record.hpp
View file

@ -25,17 +25,22 @@
** Special collection to represent object-like data.
** To be used in a context where introspection, open, extensible definitions
** and loose coupling of data representation matters. Typically, structures
** defined in terms of Record elements are linked to the actual \em core
** defined in terms of Record elements are linked to the _actual core_
** representation of the same entities relying on [diff messages](\ref diff-language.hpp).
** Record is one of the supported flavours within the DataCap of GenNode elements,
** which in turn serve as the standard handle to refer to other elements, entities,
** attributes or references within the "backbone" of the Lumiera GUI.
**
** A Record holds
** - (optionally) a type-ID string
** - a collection of _named attributes_ (key-value data)
** - a list of _enclosed children_ (contents within the "scope" of this Record)
**
** ## design decisions
** The Record type is shaped from its intended use: It serves to symbolically represent
** _objects_ in the "external tree description". Here, "objects" means objects _for real_,
** i.e. with types, fields and an enclosed scope. But \em external means that we do not work
** on these objects right here, we only represent them, for later referral, _symbolically_.
** *objects* in the "external tree description". Here, "objects" means objects _for real_,
** i.e. with types, fields and an enclosed scope. Yet the term *external* means that we do not
** work on these objects right here, we only represent them, for later referral, _symbolically_.
**
** \par rationale
** The underlying theme and motivation of this design is negative: we do not want

168
wiki/thinkPad.ichthyo.mm
View file

@ -6671,11 +6671,11 @@
<node CREATED="1487034180712" ID="ID_1371598611" MODIFIED="1518487921063" TEXT="und jedes genau wei&#xdf;, was die andern k&#xf6;nnen"/>
</node>
</node>
<node BACKGROUND_COLOR="#fefc4e" COLOR="#351d75" CREATED="1504393149140" FOLDED="true" HGAP="38" ID="ID_48107354" MODIFIED="1538942531699" TEXT="Addressierung" VSHIFT="55">
<node BACKGROUND_COLOR="#fefc4e" COLOR="#351d75" CREATED="1504393149140" FOLDED="true" HGAP="38" ID="ID_48107354" MODIFIED="1541547323971" TEXT="Addressierung" VSHIFT="55">
<arrowlink COLOR="#4f5d91" DESTINATION="ID_974158229" ENDARROW="Default" ENDINCLINATION="383;-2505;" ID="Arrow_ID_1832380552" STARTARROW="None" STARTINCLINATION="-597;127;"/>
<font BOLD="true" NAME="SansSerif" SIZE="12"/>
<icon BUILTIN="pencil"/>
<node CREATED="1504393160466" ID="ID_450547493" MODIFIED="1518487921063" TEXT="globales ID-Schema">
<node CREATED="1504393160466" ID="ID_450547493" MODIFIED="1541547317746" TEXT="globales Addre&#xdf;-Schema">
<node CREATED="1504393168946" ID="ID_390425361" MODIFIED="1518487921063" TEXT="Model-Typen"/>
<node CREATED="1504393177712" ID="ID_1686403667" MODIFIED="1518487921063" TEXT="View-Deskriptor">
<node CREATED="1504393184608" ID="ID_792210197" MODIFIED="1518487921063" TEXT="Strategy"/>
@ -6703,7 +6703,9 @@
<node CREATED="1519356887367" ID="ID_1139603062" MODIFIED="1519356897033" TEXT="wie findet man den Ort einer Komponente?"/>
<node CREATED="1519356901933" ID="ID_596521684" MODIFIED="1519356913407" TEXT="Verh&#xe4;ltnis ID / Ort">
<node CREATED="1519356920083" ID="ID_723456910" MODIFIED="1519356926342" TEXT="sind orthogonale Schemata">
<node CREATED="1519357047993" ID="ID_1706134856" MODIFIED="1519357059979" TEXT="ID = globale Identit&#xe4;t"/>
<node CREATED="1519357047993" ID="ID_1706134856" MODIFIED="1541547248389" TEXT="ID = globale Identit&#xe4;t">
<arrowlink COLOR="#6b83a8" DESTINATION="ID_1585676322" ENDARROW="Default" ENDINCLINATION="738;0;" ID="Arrow_ID_174361092" STARTARROW="None" STARTINCLINATION="1067;-74;"/>
</node>
<node CREATED="1519357060599" ID="ID_975802429" MODIFIED="1519357070810" TEXT="Ort = Topologie + Typ">
<node CREATED="1519357081868" ID="ID_1484266304" MODIFIED="1519357090975" TEXT="Ortsnamen sind generisch"/>
<node CREATED="1519357091795" ID="ID_68008128" MODIFIED="1519357096374" TEXT="sie werden lokal verstanden"/>
@ -20098,7 +20100,7 @@
<node CREATED="1533400281627" ID="ID_1248361340" MODIFIED="1533400375591" TEXT="geht noch nicht -- logging-Strategy fehlt">
<icon BUILTIN="stop-sign"/>
</node>
<node BACKGROUND_COLOR="#eee5c3" COLOR="#990000" CREATED="1533400377118" ID="ID_1072134705" MODIFIED="1539388435770" TEXT="#211 handling pattern for dispatch">
<node BACKGROUND_COLOR="#eee5c3" COLOR="#990000" CREATED="1533400377118" ID="ID_1072134705" MODIFIED="1541547696433" TEXT="#211 handling pattern for dispatch">
<arrowlink COLOR="#ca91c2" DESTINATION="ID_1192893155" ENDARROW="Default" ENDINCLINATION="1415;0;" ID="Arrow_ID_207842771" STARTARROW="None" STARTINCLINATION="2581;0;"/>
<icon BUILTIN="hourglass"/>
</node>
@ -20979,6 +20981,10 @@
</node>
</node>
</node>
<node CREATED="1541547600640" ID="ID_787025622" MODIFIED="1541547663157" TEXT="Element-IDs m&#xfc;ssen eindeutig sein">
<arrowlink COLOR="#c9876a" DESTINATION="ID_1850412206" ENDARROW="Default" ENDINCLINATION="49;-155;" ID="Arrow_ID_1571993328" STARTARROW="None" STARTINCLINATION="-11;173;"/>
<icon BUILTIN="messagebox_warning"/>
</node>
</node>
</node>
</node>
@ -21033,6 +21039,128 @@
<font ITALIC="true" NAME="SansSerif" SIZE="12"/>
<icon BUILTIN="info"/>
</node>
<node CREATED="1541545653978" ID="ID_1534432315" MODIFIED="1541545660929" TEXT="UI-Element - Identit&#xe4;t">
<node BACKGROUND_COLOR="#ccb59b" COLOR="#6e2a38" CREATED="1541545674669" ID="ID_1585676322" MODIFIED="1541547248389" TEXT="UI-Elemente sind global eindeutig">
<arrowlink COLOR="#7894b4" DESTINATION="ID_189279804" ENDARROW="Default" ENDINCLINATION="272;-358;" ID="Arrow_ID_540125984" STARTARROW="None" STARTINCLINATION="-618;10;"/>
<linktarget COLOR="#6b83a8" DESTINATION="ID_1585676322" ENDARROW="Default" ENDINCLINATION="738;0;" ID="Arrow_ID_174361092" SOURCE="ID_1706134856" STARTARROW="None" STARTINCLINATION="1067;-74;"/>
<font ITALIC="true" NAME="SansSerif" SIZE="14"/>
<icon BUILTIN="yes"/>
</node>
<node CREATED="1541545696185" ID="ID_1907010009" MODIFIED="1541545798109" TEXT="Grund: UI-Bus - Routing">
<icon BUILTIN="info"/>
</node>
<node CREATED="1541545933006" ID="ID_1850412206" MODIFIED="1541547731516" TEXT="t&#xfc;ckisches Problem">
<linktarget COLOR="#c9876a" DESTINATION="ID_1850412206" ENDARROW="Default" ENDINCLINATION="49;-155;" ID="Arrow_ID_1571993328" SOURCE="ID_787025622" STARTARROW="None" STARTINCLINATION="-11;173;"/>
<linktarget COLOR="#c9876a" DESTINATION="ID_1850412206" ENDARROW="Default" ENDINCLINATION="369;179;" ID="Arrow_ID_1229280605" SOURCE="ID_659707505" STARTARROW="None" STARTINCLINATION="586;-203;"/>
<icon BUILTIN="messagebox_warning"/>
<node CREATED="1541545944079" ID="ID_1737663580" MODIFIED="1541545963000" TEXT="ein Duplikat ersetzt stillschweigend die Registrierung"/>
<node CREATED="1541545963822" ID="ID_1562348206" MODIFIED="1541546016778" TEXT="Identit&#xe4;t beruht auf EntryID (Hash)"/>
<node CREATED="1541545975779" ID="ID_1748214927" MODIFIED="1541546024401" TEXT="diese(r) wird aber systematisch gebildet"/>
<node CREATED="1541546204541" ID="ID_1625379453" MODIFIED="1541546208976" TEXT="speziell...">
<node CREATED="1541546209896" ID="ID_1049660229" MODIFIED="1541546245931" TEXT="Kind: _CHILD_&lt;typ&gt;.&lt;cnt&gt;">
<node CREATED="1541546489419" ID="ID_282481336" MODIFIED="1541546548022" TEXT="automatisch global eindeutig">
<richcontent TYPE="NOTE"><html>
<head>
</head>
<body>
<p>
weil wir einen Mechanismus haben, die &lt;cnt&gt;-Dekoration pro Typ global hochzuz&#228;hlen (treadsafe)
</p>
</body>
</html>
</richcontent>
</node>
<node CREATED="1541546556994" ID="ID_35993355" MODIFIED="1541546573135" TEXT="hash-seed: der &lt;typ&gt;-Hash"/>
</node>
<node CREATED="1541546415736" ID="ID_1483102981" MODIFIED="1541546432862" TEXT="Attribut: key">
<node CREATED="1541546579096" ID="ID_728290559" MODIFIED="1541546602798">
<richcontent TYPE="NODE"><html>
<head>
</head>
<body>
<p>
Problem: key nur <i>innerhalb</i>&#160;des Objektes eindeutig
</p>
</body>
</html>
</richcontent>
<icon BUILTIN="broken-line"/>
</node>
<node CREATED="1541547820403" ID="ID_1229228521" MODIFIED="1541775004416" TEXT="L&#xf6;sung: Hash-Chaining">
<icon BUILTIN="button_cancel"/>
<node CREATED="1541547837646" ID="ID_508395323" MODIFIED="1541547854627" TEXT="&#xe4;hnlich wie im Merkle-Tree">
<icon BUILTIN="idea"/>
</node>
<node CREATED="1541547855766" ID="ID_1691211097" MODIFIED="1541547867017" TEXT="Hash des Vaters als seed">
<node CREATED="1541552824556" ID="ID_42859602" MODIFIED="1541552831542" TEXT="geht nicht">
<icon BUILTIN="stop-sign"/>
</node>
<node CREATED="1541552832731" ID="ID_346770424" MODIFIED="1541552877349" TEXT="bricht die Subsidiarit&#xe4;t">
<richcontent TYPE="NOTE"><html>
<head>
</head>
<body>
<p>
...denn dann m&#252;&#223;te das Attribut
</p>
<p>
von dem Container (GenNode) wissen, der es zwei Ebenen h&#246;her enth&#228;lt und umschlie&#223;t
</p>
</body>
</html>
</richcontent>
<icon BUILTIN="broken-line"/>
</node>
<node CREATED="1541774981285" ID="ID_1038144488" MODIFIED="1541774996472" TEXT="ist letzten Endes auch blo&#xdf; random()"/>
</node>
</node>
<node CREATED="1541775187418" ID="ID_1058458763" MODIFIED="1541789739897" TEXT="Frage: Reproduzierbarkeit irrelevant?">
<richcontent TYPE="NOTE"><html>
<head>
</head>
<body>
<p>
...es kommt (vielleicht) &#252;berhaupt nicht darauf an,
</p>
<p>
da&#223; der Hash einer Attribut-ID <i>reproduzierbar</i>&#160;ist (auf Basis der symbilschen ID).
</p>
<p>
Der Hash kann genausogut eine Zufallszahl sein
</p>
</body>
</html>
</richcontent>
<icon BUILTIN="help"/>
<node CREATED="1541775381760" ID="ID_681940327" MODIFIED="1541775392922" TEXT="denn: get sucht per Symbol"/>
<node CREATED="1541775428125" ID="ID_1569956089" MODIFIED="1541775485774" TEXT="und: einige Attribute haben notwendig eine extern definierte ID">
<richcontent TYPE="NOTE"><html>
<head>
</head>
<body>
<p>
...n&#228;mlich diejenigen, die <i>selber </i>Modell-Elemente sind.
</p>
<p>
Und genau diese speziellen Objekt-Attribute sind der Anla&#223;,
</p>
<p>
sich &#252;ber dieses Problem Gedanken zu machen
</p>
</body>
</html>
</richcontent>
</node>
</node>
</node>
</node>
</node>
</node>
<node CREATED="1523021670034" ID="ID_1102842396" MODIFIED="1523021676897" TEXT="Einstiegspunkte">
<icon BUILTIN="idea"/>
<node CREATED="1523021679960" ID="ID_1386792927" MODIFIED="1523021704154">
@ -21253,7 +21381,7 @@
<node CREATED="1448070559466" ID="ID_182430638" MODIFIED="1518487921085" TEXT="Controller"/>
</node>
<node CREATED="1448070583679" HGAP="69" ID="ID_1248152908" MODIFIED="1538871387818" TEXT="Protokoll" VSHIFT="-1">
<node CREATED="1448078263344" FOLDED="true" ID="ID_1136748666" MODIFIED="1535638754133" TEXT="Verhaltensweisen">
<node CREATED="1448078263344" FOLDED="true" ID="ID_1136748666" MODIFIED="1541546653282" TEXT="Verhaltensweisen">
<cloud COLOR="#e0d6ba"/>
<icon BUILTIN="info"/>
<node CREATED="1448078268223" ID="ID_1027574047" MODIFIED="1518487921085" TEXT="Lebenszyklus">
@ -21414,7 +21542,7 @@
</node>
</node>
</node>
<node CREATED="1448658633478" FOLDED="true" HGAP="99" ID="ID_314439240" MODIFIED="1538871380938" TEXT="Design" VSHIFT="13">
<node CREATED="1448658633478" FOLDED="true" HGAP="99" ID="ID_314439240" MODIFIED="1541547787225" TEXT="Design" VSHIFT="13">
<icon BUILTIN="button_ok"/>
<node CREATED="1448658692023" ID="ID_339186676" MODIFIED="1518487921085">
<richcontent TYPE="NODE"><html>
@ -21528,6 +21656,22 @@
</node>
</node>
</node>
<node CREATED="1541546692289" ID="ID_189279804" MODIFIED="1541546864673">
<richcontent TYPE="NODE"><html>
<head>
</head>
<body>
<p>
<b>Identit&#228;t</b>&#160;== Bus-ID
</p>
</body>
</html>
</richcontent>
<linktarget COLOR="#7894b4" DESTINATION="ID_189279804" ENDARROW="Default" ENDINCLINATION="272;-358;" ID="Arrow_ID_540125984" SOURCE="ID_1585676322" STARTARROW="None" STARTINCLINATION="-618;10;"/>
<node CREATED="1541546715849" ID="ID_503690063" MODIFIED="1541546722489" TEXT="sollte global eindeutig sein"/>
<node CREATED="1541546733765" ID="ID_1010323480" MODIFIED="1541546741208" TEXT="wird per Diff &#xfc;bermittelt"/>
</node>
<node CREATED="1448658696638" ID="ID_1235910089" MODIFIED="1518487921086" TEXT="slots">
<node CREATED="1451177440022" ID="ID_1603816152" MODIFIED="1518487921086" TEXT="expand">
<icon BUILTIN="button_ok"/>
@ -21615,7 +21759,7 @@
</node>
</node>
</node>
<node CREATED="1535639028984" FOLDED="true" ID="ID_316446199" MODIFIED="1538871369730" TEXT="hilfs-Abstraktionen">
<node CREATED="1535639028984" FOLDED="true" ID="ID_316446199" MODIFIED="1541545385363" TEXT="hilfs-Abstraktionen">
<linktarget COLOR="#709eaf" DESTINATION="ID_316446199" ENDARROW="Default" ENDINCLINATION="-354;-490;" ID="Arrow_ID_1105268233" SOURCE="ID_447101734" STARTARROW="None" STARTINCLINATION="-3385;0;"/>
<node CREATED="1535639151330" ID="ID_301022990" MODIFIED="1535639159958" TEXT="mix-in">
<icon BUILTIN="yes"/>
@ -39273,7 +39417,7 @@
<icon BUILTIN="flag-yellow"/>
</node>
</node>
<node CREATED="1539270417847" ID="ID_1555798999" MODIFIED="1539388406968" TEXT="korrekte Diff-Struktur">
<node CREATED="1539270417847" ID="ID_1555798999" MODIFIED="1541547682934" TEXT="korrekte Diff-Struktur">
<linktarget COLOR="#cbada9" DESTINATION="ID_1555798999" ENDARROW="Default" ENDINCLINATION="1069;-129;" ID="Arrow_ID_46239762" SOURCE="ID_1136748343" STARTARROW="None" STARTINCLINATION="-474;40;"/>
<linktarget COLOR="#d47366" DESTINATION="ID_1555798999" ENDARROW="Default" ENDINCLINATION="713;-263;" ID="Arrow_ID_971172326" SOURCE="ID_1387553695" STARTARROW="None" STARTINCLINATION="-1999;120;"/>
<linktarget COLOR="#d47366" DESTINATION="ID_1555798999" ENDARROW="Default" ENDINCLINATION="590;-127;" ID="Arrow_ID_308349501" SOURCE="ID_1435731309" STARTARROW="None" STARTINCLINATION="915;0;"/>
@ -39304,6 +39448,12 @@
</node>
</node>
</node>
<node CREATED="1541547600640" HGAP="79" ID="ID_659707505" MODIFIED="1541547731516" TEXT="Element-IDs m&#xfc;ssen eindeutig sein" VSHIFT="10">
<arrowlink COLOR="#c9876a" DESTINATION="ID_1850412206" ENDARROW="Default" ENDINCLINATION="369;179;" ID="Arrow_ID_1229280605" STARTARROW="None" STARTINCLINATION="586;-203;"/>
<icon BUILTIN="messagebox_warning"/>
<node CREATED="1541547743885" ID="ID_1112550435" MODIFIED="1541547750312" TEXT="wegen UI-Bus-Routing"/>
<node CREATED="1541547751020" ID="ID_566590492" MODIFIED="1541547764950" TEXT="Aber: Attribute werden lokal erzeugt"/>
</node>
</node>
<node CREATED="1539270417847" ID="ID_946219609" MODIFIED="1539388465978" TEXT="Reaktion auf Diff-Fehler">
<linktarget COLOR="#d47366" DESTINATION="ID_946219609" ENDARROW="Default" ENDINCLINATION="713;-263;" ID="Arrow_ID_1085344706" SOURCE="ID_19523487" STARTARROW="Default" STARTINCLINATION="-1999;120;"/>
@ -39319,7 +39469,7 @@
<font ITALIC="true" NAME="SansSerif" SIZE="14"/>
<icon BUILTIN="yes"/>
</node>
<node BACKGROUND_COLOR="#eee5c3" COLOR="#990000" CREATED="1533400707072" ID="ID_1192893155" MODIFIED="1539388435770" TEXT="#211 handling pattern for dispatch">
<node BACKGROUND_COLOR="#eee5c3" COLOR="#990000" CREATED="1533400707072" ID="ID_1192893155" MODIFIED="1541547696433" TEXT="#211 handling pattern for dispatch">
<linktarget COLOR="#ca91c2" DESTINATION="ID_1192893155" ENDARROW="Default" ENDINCLINATION="1415;0;" ID="Arrow_ID_207842771" SOURCE="ID_1072134705" STARTARROW="None" STARTINCLINATION="2581;0;"/>
<icon BUILTIN="hourglass"/>
</node>