diff --git a/DALI.tex b/DALI.tex index 555fa2d..a73d579 100644 --- a/DALI.tex +++ b/DALI.tex @@ -233,7 +233,7 @@ \subsection{Asynchronous Execution: DALI-async} A concrete DAL service specification will specify zero or more asynchronous job submission resources and whether they are mandatory or optional. It may mandate a specific resource name to support simple client use, or it can allow the -resource name to be described in the service metadata (Section 2.5 ). +resource name to be described in the service metadata (Section~\ref{sec:vosi-capabilities}). \subsection{Synchronous Execution: DALI-sync} \label{sec:dali-sync} @@ -266,7 +266,8 @@ \subsection{Synchronous Execution: DALI-sync} A concrete DAL service specification will specify zero or more synchronous job submission resources and whether they are mandatory or optional. It may mandate a specific resource name to support simple client use, or it can allow the -resource name to be described in the service capability metadata (Section 2.5 ). +resource name to be described in the service capability metadata +(Section~\ref{sec:vosi-capabilities}). \subsection{DALI-examples} \label{sec:dali-examples} @@ -287,7 +288,8 @@ \subsection{DALI-examples} $$ DAL services may implement the /examples resource and include it in the -capabilities described by the VOSI-capabilities resource (Section 2.5 ); if they +capabilities described by the VOSI-capabilities resource +(Section~\ref{sec:vosi-capabilities}); if they do not, retrieving its URL must yield a 404 HTTP error code. The document at /examples must be well-formed XML. This restriction is imposed @@ -1075,8 +1077,8 @@ \subsubsection{RESPONSEFORMAT} In some cases, the specification for a specific format may be parameterised (e.g., the media type may include optional semi-colon and additional key-value parameters). A DAL service must accept a RESPONSEFORMAT parameter indicating a -format that the service supports and should fail (Section 4.2 ) where the -RESPONSEFORMAT parameter specifies a format not supported by the service +format that the service supports and should fail (Section~\ref{sec:response-error}) +where the RESPONSEFORMAT parameter specifies a format not supported by the service implementation. A concrete DAL service specification will specify any mandatory or optional @@ -1120,11 +1122,11 @@ \subsubsection{MAXREC} enforce a limit on the value of MAXREC that is smaller than the value in the request. If the size of the result exceeds the resulting limit, the service must only return the requested number of rows. If the result set is truncated in this -fashion, it must include an overflow indicator as specified in Section 4.4.1 . +fashion, it must include an overflow indicator as specified in Section \ref{sec:response-overflow}. The service must support the special value of MAXREC=0. This value indicates that, in the event of an otherwise valid request, a valid response be returned -containing metadata, no results, and an overflow indicator (Section 4.4.1 ). The +containing metadata, no results, and an overflow indicator. The service is not required to execute the request and the overflow indicator does not necessarily mean that there is at least one record satisfying the query. The service may perform validation and may try to execute the request, in which case @@ -1325,7 +1327,7 @@ \subsection{Redirection} A concrete DAL service specification may require that HTTP redirects (302 or 303) be used to communicate the location of an alternate resource which should be accessed by the client via the HTTP GET method. For example, the UWS pattern -used for DALI-async (Section 2.1 ) requires this behaviour. Even when not +used for DALI-async (\ref{sec:dali-async}) requires this behaviour. Even when not required, concrete DAL service specifications must allow implementers to use redirects and clients must be prepared to follow these redirects using normal HTTP semantics \citep{std:HTTP}. @@ -1389,12 +1391,11 @@ \subsection{Use of VOTable} \subsubsection{Overflow} \label{sec:response-overflow} -If an overflow occurs (for example, result exceeds MAXREC), the service must include an -\xmlel{INFO} -element in the \xmlel{RESOURCE} with \verb|name="QUERY\_STATUS"| and the -\verb|value="OVERFLOW"|. If -the initial \xmlel{INFO} element (above) specified the overflow, no further elements are -needed, e.g.: +If an overflow occurs (for example, result exceeds MAXREC) and the output format +is VOTable, the service must include an \xmlel{INFO} element in the \xmlel{RESOURCE} +with \verb|name="QUERY\_STATUS"| and the \verb|value="OVERFLOW"|. If the initial +\xmlel{INFO} element (above) specified the overflow, no further elements are needed, +e.g.: \begin{lstlisting}[language=XML] @@ -1416,6 +1417,10 @@ \subsubsection{Overflow} \end{lstlisting} +There is no defined mechanism to indicate overflow (truncation) of output for formats +other than VOTable. Specifically, simple text formats like \verb|text/csv| and +\verb|text/tab-separated-values| do not support indicating overflow. + In general, services may truncate the output results when reaching a limit. A default or user-specified value of the MAXREC parameter is a common mechanism that causes truncation of results, but service providers may also impose limits in services that do not use