Arvados

h1. Keep locator format

Draft. See discussion at #2755

<pre>

locator       ::= sized-digest hint*

sized-digest  ::= digest size-hint

digest        ::= <32 lowercase hexadecimal digits>

size-hint     ::= "+" [0-9]+

hint          ::= "+" hint-type hint-content

hint-type     ::= [A-Z]+

hint-content  ::= [A-Za-z0-9@_-]*

sign-hint      ::= "+A" <40 lowercase hexadecimal digits> "@" sign-timestamp

sign-timestamp ::= <8 lowercase hexadecimal digits>

</pre>

h2. Regular expressions

Is it a valid locator?

<pre>

/^([0-9a-f]{32})\+([0-9]+)(\+[A-Z][-A-Za-z0-9@_]*)*$/

</pre>

h2. Good examples

|@d41d8cd98f00b204e9800998ecf8427e+0@|

|@d41d8cd98f00b204e9800998ecf8427e+0+Z@|

|@d41d8cd98f00b204e9800998ecf8427e+0+Z+Ada39a3ee5e6b4b0d3255bfef95601890afd80709@53bed294@|

h2. Bad examples

||Why|

|@d41d8cd98f00b204e9800998ecf8427e@|No size hint|

|@d41d8cd98f00b204e9800998ecf8427e+Z+0@|Other hint before size hint|

|@d41d8cd98f00b204e9800998ecf8427e+0+0@|Multiple size hints|

|@d41d8cd98f00b204e9800998ecf8427e+0+z@|Hint does not start with uppercase letter|

|@d41d8cd98f00b204e9800998ecf8427e+0+Zfoo*bar@|Hint contains invalid character @*@|