/// <summary>
/// Write the ATOM metadata for an entry
/// </summary>
/// <param name="writer">The Xml writer to write to.</param>
/// <param name="baseUri">The base Uri of the document or null if none was specified.</param>
/// <param name="entry">The entry for which to write the metadata.</param>
/// <param name="epmEntryMetadata">The ATOM metadata for the entry which came from EPM.</param>
internal static void WriteEntryMetadata(XmlWriter writer, Uri baseUri, ODataEntry entry, AtomEntryMetadata epmEntryMetadata)
{
DebugUtils.CheckNoExternalCallers();
Debug.Assert(writer != null, "writer != null");
// TODO, ckerer: implement the rule around authors (an entry has to have an author directly or in the <entry:source> unless the feed has an author).
// currently we make all entries have an author.
AtomEntryMetadata customEntryMetadata = entry.GetAnnotation <AtomEntryMetadata>();
AtomEntryMetadata entryMetadata = ODataAtomWriterMetadataEpmMergeUtils.MergeCustomAndEpmEntryMetadata(customEntryMetadata, epmEntryMetadata);
if (entryMetadata == null)
{
// write all required metadata elements with default content
// <atom:title></atom:title>
ODataAtomWriterUtils.WriteEmptyElement(writer, AtomConstants.AtomNamespacePrefix, AtomConstants.AtomTitleElementName, AtomConstants.AtomNamespace);
// <atom:updated>dateTimeOffset</atom:updated>
// NOTE: the <updated> element is required and if not specified the best we can do is to create a default
// one with the current date/time.
ODataAtomWriterUtils.WriteElementWithTextContent(writer, AtomConstants.AtomNamespacePrefix, AtomConstants.AtomUpdatedElementName, AtomConstants.AtomNamespace, ODataAtomConvert.ToString(DateTimeOffset.UtcNow));
WriteEmptyAuthor(writer);
}
else
{
// <atom:title>text</atom:title>
// NOTE: writes an empty element even if no title was specified since the title is required
ODataAtomWriterMetadataUtils.WriteTextConstruct(writer, AtomConstants.AtomNamespacePrefix, AtomConstants.AtomTitleElementName, AtomConstants.AtomNamespace, entryMetadata.Title);
AtomTextConstruct summary = entryMetadata.Summary;
if (summary != null)
{
// <atom:summary>text</atom:summary>
ODataAtomWriterMetadataUtils.WriteTextConstruct(writer, AtomConstants.AtomNamespacePrefix, AtomConstants.AtomSummaryElementName, AtomConstants.AtomNamespace, summary);
}
DateTimeOffset?published = entryMetadata.Published;
if (published.HasValue)
{
// <atom:published>dateTimeOffset</atom:published>
ODataAtomWriterUtils.WriteElementWithTextContent(writer, AtomConstants.AtomNamespacePrefix, AtomConstants.AtomPublishedElementName, AtomConstants.AtomNamespace, ODataAtomConvert.ToString(published.Value));
}
// <atom:updated>date</atom:updated>
// NOTE: the <updated> element is required and if not specified the best we can do is to create a default
// one with the current date/time.
DateTimeOffset updated = entryMetadata.Updated.HasValue ? entryMetadata.Updated.Value : DateTimeOffset.UtcNow;
ODataAtomWriterUtils.WriteElementWithTextContent(
writer,
AtomConstants.AtomNamespacePrefix,
AtomConstants.AtomUpdatedElementName,
AtomConstants.AtomNamespace,
ODataAtomConvert.ToString(updated));
bool wroteAuthor = false;
IEnumerable <AtomPersonMetadata> authors = entryMetadata.Authors;
if (authors != null)
{
foreach (AtomPersonMetadata author in authors)
{
if (author == null)
{
throw new ODataException(Strings.ODataAtomWriterMetadataUtils_AuthorMetadataMustNotContainNull);
}
// <atom:author>author data</atom:author>
writer.WriteStartElement(AtomConstants.AtomNamespacePrefix, AtomConstants.AtomAuthorElementName, AtomConstants.AtomNamespace);
WritePersonMetadata(writer, baseUri, author);
writer.WriteEndElement();
wroteAuthor = true;
}
}
if (!wroteAuthor)
{
// write empty authors since they are required
WriteEmptyAuthor(writer);
}
IEnumerable <AtomPersonMetadata> contributors = entryMetadata.Contributors;
if (contributors != null)
{
foreach (AtomPersonMetadata contributor in contributors)
{
if (contributor == null)
{
throw new ODataException(Strings.ODataAtomWriterMetadataUtils_ContributorMetadataMustNotContainNull);
}
// <atom:contributor>contributor data</atom:contributor>
writer.WriteStartElement(AtomConstants.AtomNamespacePrefix, AtomConstants.AtomContributorElementName, AtomConstants.AtomNamespace);
WritePersonMetadata(writer, baseUri, contributor);
writer.WriteEndElement();
}
}
IEnumerable <AtomLinkMetadata> links = entryMetadata.Links;
if (links != null)
{
foreach (AtomLinkMetadata link in links)
{
if (link == null)
{
throw new ODataException(Strings.ODataAtomWriterMetadataUtils_LinkMetadataMustNotContainNull);
}
// <atom:link>...</atom:link>
WriteAtomLinkMetadata(writer, baseUri, link);
}
}
IEnumerable <AtomCategoryMetadata> categories = entryMetadata.Categories;
if (categories != null)
{
foreach (AtomCategoryMetadata category in categories)
{
if (category == null)
{
throw new ODataException(Strings.ODataAtomWriterMetadataUtils_CategoryMetadataMustNotContainNull);
}
// <atom:category term="..." scheme="..." label="..."></atom:category>
WriteCategory(writer, category);
}
}
if (entryMetadata.Rights != null)
{
// <atom:rights>rights</atom:rights>
ODataAtomWriterMetadataUtils.WriteTextConstruct(writer, AtomConstants.AtomNamespacePrefix, AtomConstants.AtomRightsElementName, AtomConstants.AtomNamespace, entryMetadata.Rights);
}
Uri icon = entryMetadata.Icon;
if (icon != null)
{
// <atom:icon>Uri</atom:icon>
ODataAtomWriterUtils.WriteElementWithTextContent(
writer,
AtomConstants.AtomNamespacePrefix,
AtomConstants.AtomIconElementName,
AtomConstants.AtomNamespace,
AtomUtils.ToUrlAttributeValue(icon, baseUri));
}
AtomFeedMetadata source = entryMetadata.Source;
if (source != null)
{
// <atom:source>
writer.WriteStartElement(AtomConstants.AtomNamespacePrefix, AtomConstants.AtomSourceElementName, AtomConstants.AtomNamespace);
WriteFeedMetadata(writer, baseUri, source, null);
// </atom:source>
writer.WriteEndElement();
}
}
}
/// <summary>
/// Write the given feed metadata in atom format
/// </summary>
/// <param name="writer">The Xml writer to write to.</param>
/// <param name="baseUri">The base Uri of the document or null if none was specified.</param>
/// <param name="feedMetadata">The metadata to write.</param>
/// <param name="feed">The feed for which to write the meadata or null if it is the metadata of an atom:source element.</param>
private static void WriteFeedMetadata(XmlWriter writer, Uri baseUri, AtomFeedMetadata feedMetadata, ODataFeed feed)
{
Debug.Assert(writer != null, "writer != null");
Debug.Assert(feedMetadata != null, "Feed metadata must not be null!");
// <atom:id>text</atom:id>
// NOTE: this is the Id of the feed. For a regular feed this is stored on the feed itself;
// if used in the context of an <atom:source> element it is stored in metadata
Debug.Assert(feed == null || !string.IsNullOrEmpty(feed.Id), "The feed Id should have been validated by now.");
string id = feed == null ? feedMetadata.SourceId : feed.Id;
ODataAtomWriterUtils.WriteElementWithTextContent(
writer,
AtomConstants.AtomNamespacePrefix,
AtomConstants.AtomIdElementName,
AtomConstants.AtomNamespace,
id);
// <atom:title>text</atom:title>
// NOTE: write an empty element if no title is specified since the element is required
ODataAtomWriterMetadataUtils.WriteTextConstruct(writer, AtomConstants.AtomNamespacePrefix, AtomConstants.AtomTitleElementName, AtomConstants.AtomNamespace, feedMetadata.Title);
if (feedMetadata.Subtitle != null)
{
// <atom:subtitle>text</atom:subtitle>
ODataAtomWriterMetadataUtils.WriteTextConstruct(writer, AtomConstants.AtomNamespacePrefix, AtomConstants.AtomSubtitleElementName, AtomConstants.AtomNamespace, feedMetadata.Subtitle);
}
// <atom:updated>date</atom:updated>
// NOTE: the <updated> element is required and if not specified the best we can do is to create a default
// one with the current date/time.
DateTimeOffset updated = feedMetadata.Updated.HasValue ? feedMetadata.Updated.Value : DateTimeOffset.UtcNow;
ODataAtomWriterUtils.WriteElementWithTextContent(
writer,
AtomConstants.AtomNamespacePrefix,
AtomConstants.AtomUpdatedElementName,
AtomConstants.AtomNamespace,
ODataAtomConvert.ToString(updated));
IEnumerable <AtomPersonMetadata> authors = feedMetadata.Authors;
if (authors != null)
{
foreach (AtomPersonMetadata author in authors)
{
// <atom:author>author data</atom:author>
writer.WriteStartElement(AtomConstants.AtomNamespacePrefix, AtomConstants.AtomAuthorElementName, AtomConstants.AtomNamespace);
WritePersonMetadata(writer, baseUri, author);
writer.WriteEndElement();
}
}
IEnumerable <AtomLinkMetadata> links = feedMetadata.Links;
if (links != null)
{
foreach (AtomLinkMetadata link in links)
{
// <atom:link>...</atom:link>
WriteAtomLinkMetadata(writer, baseUri, link);
}
}
IEnumerable <AtomCategoryMetadata> categories = feedMetadata.Categories;
if (categories != null)
{
foreach (AtomCategoryMetadata category in categories)
{
// <atom:category term="..." scheme="..." label="..."></atom:category>
WriteCategory(writer, category);
}
}
Uri logo = feedMetadata.Logo;
if (logo != null)
{
// <atom:logo>Uri</atom:logo>
ODataAtomWriterUtils.WriteElementWithTextContent(
writer,
AtomConstants.AtomNamespacePrefix,
AtomConstants.AtomLogoElementName,
AtomConstants.AtomNamespace,
AtomUtils.ToUrlAttributeValue(logo, baseUri));
}
if (feedMetadata.Rights != null)
{
// <atom:rights>rights</atom:rights>
ODataAtomWriterMetadataUtils.WriteTextConstruct(
writer,
AtomConstants.AtomNamespacePrefix,
AtomConstants.AtomRightsElementName,
AtomConstants.AtomNamespace,
feedMetadata.Rights);
}
IEnumerable <AtomPersonMetadata> contributors = feedMetadata.Contributors;
if (contributors != null)
{
foreach (AtomPersonMetadata contributor in contributors)
{
// <atom:contributor>contributor data</atom:contributor>
writer.WriteStartElement(AtomConstants.AtomNamespacePrefix, AtomConstants.AtomContributorElementName, AtomConstants.AtomNamespace);
WritePersonMetadata(writer, baseUri, contributor);
writer.WriteEndElement();
}
}
AtomGeneratorMetadata generator = feedMetadata.Generator;
if (generator != null)
{
// <atom:generator uri="..." version="...">name</atom:generator>
writer.WriteStartElement(AtomConstants.AtomNamespacePrefix, AtomConstants.AtomGeneratorElementName, AtomConstants.AtomNamespace);
if (generator.Uri != null)
{
writer.WriteAttributeString(AtomConstants.AtomGeneratorUriAttributeName, AtomUtils.ToUrlAttributeValue(generator.Uri, baseUri));
}
if (!string.IsNullOrEmpty(generator.Version))
{
writer.WriteAttributeString(AtomConstants.AtomGeneratorVersionAttributeName, generator.Version);
}
writer.WriteString(generator.Name);
writer.WriteEndElement();
}
Uri icon = feedMetadata.Icon;
if (icon != null)
{
// <atom:icon>Uri</atom:icon>
ODataAtomWriterUtils.WriteElementWithTextContent(
writer,
AtomConstants.AtomNamespacePrefix,
AtomConstants.AtomIconElementName,
AtomConstants.AtomNamespace,
AtomUtils.ToUrlAttributeValue(icon, baseUri));
}
}
/// <summary>
/// Write the metadata attributes of a link in ATOM format
/// </summary>
/// <param name="writer">The Xml writer to write to.</param>
/// <param name="relation">The value for the 'rel' attribute.</param>
/// <param name="href">The value for the 'href' attribute.</param>
/// <param name="hrefLang">The value for the 'hreflang' attribute.</param>
/// <param name="title">The value for the 'title' attribute.</param>
/// <param name="mediaType">The value for the 'type' attribute.</param>
/// <param name="length">The value for the 'length' attribute.</param>
private static void WriteAtomLinkMetadataAttributes(XmlWriter writer, string relation, string href, string hrefLang, string title, string mediaType, int?length)
{
Debug.Assert(writer != null, "writer != null");
// rel="..."
if (relation != null)
{
writer.WriteAttributeString(AtomConstants.AtomLinkRelationAttributeName, relation);
}
// type="..."
if (mediaType != null)
{
writer.WriteAttributeString(AtomConstants.AtomLinkTypeAttributeName, mediaType);
}
// title="..."
if (title != null)
{
writer.WriteAttributeString(AtomConstants.AtomLinkTitleAttributeName, title);
}
// href="..."
if (href == null)
{
throw new ODataException(Strings.ODataAtomWriterMetadataUtils_LinkMustSpecifyHref);
}
writer.WriteAttributeString(AtomConstants.AtomHRefAttributeName, href);
// hreflang="..."
if (hrefLang != null)
{
writer.WriteAttributeString(AtomConstants.AtomLinkHrefLangAttributeName, hrefLang);
}
// length="..."
if (length.HasValue)
{
writer.WriteAttributeString(AtomConstants.AtomLinkLengthAttributeName, ODataAtomConvert.ToString(length.Value));
}
}
/// <summary>
/// Write the ATOM metadata for a feed
/// </summary>
/// <param name="writer">The Xml writer to write to.</param>
/// <param name="baseUri">The base Uri of the document or null if none was specified.</param>
/// <param name="feed">The feed for which to write the metadata.</param>
internal static void WriteFeedMetadata(XmlWriter writer, Uri baseUri, ODataFeed feed)
{
DebugUtils.CheckNoExternalCallers();
Debug.Assert(writer != null, "writer != null");
Debug.Assert(feed != null, "feed != null");
AtomFeedMetadata feedMetadata = feed.GetAnnotation <AtomFeedMetadata>();
if (feedMetadata == null)
{
// create the required metadata elements with default values.
// <atom:id>idValue</atom:id>
Debug.Assert(!string.IsNullOrEmpty(feed.Id), "The feed Id should have been validated by now.");
ODataAtomWriterUtils.WriteElementWithTextContent(
writer,
AtomConstants.AtomNamespacePrefix,
AtomConstants.AtomIdElementName,
AtomConstants.AtomNamespace,
feed.Id);
// <atom:title></atom:title>
ODataAtomWriterUtils.WriteEmptyElement(writer, AtomConstants.AtomNamespacePrefix, AtomConstants.AtomTitleElementName, AtomConstants.AtomNamespace);
// <atom:updated>dateTimeOffset</atom:updated>
ODataAtomWriterUtils.WriteElementWithTextContent(writer, AtomConstants.AtomNamespacePrefix, AtomConstants.AtomUpdatedElementName, AtomConstants.AtomNamespace, ODataAtomConvert.ToString(DateTimeOffset.UtcNow));
}
else
{
WriteFeedMetadata(writer, baseUri, feedMetadata, feed);
}
}