/// <summary>
        /// Adds a new contributor to entry metadata.
        /// </summary>
        /// <param name="entryMetadata">The entry metadata to add the contributor to.</param>
        /// <param name="contributorMetadata">The contributor metadata to add.</param>
        internal static void AddContributor(this AtomEntryMetadata entryMetadata, AtomPersonMetadata contributorMetadata)
        {
            Debug.Assert(entryMetadata != null, "entryMetadata != null");
            Debug.Assert(contributorMetadata != null, "contributorMetadata != null");

            entryMetadata.Contributors = entryMetadata.Contributors.ConcatToReadOnlyEnumerable("Contributors", contributorMetadata);
        }
        /// <summary>
        /// Adds a new author to entry metadata.
        /// </summary>
        /// <param name="entryMetadata">The entry metadata to add the author to.</param>
        /// <param name="authorMetadata">The author metadata to add.</param>
        internal static void AddAuthor(this AtomEntryMetadata entryMetadata, AtomPersonMetadata authorMetadata)
        {
            Debug.Assert(entryMetadata != null, "entryMetadata != null");
            Debug.Assert(authorMetadata != null, "authorMetadata != null");

            entryMetadata.Authors = entryMetadata.Authors.ConcatToReadOnlyEnumerable("Authors", authorMetadata);
        }
        /// <summary>
        /// Writes the specified start/end tags and the specified person metadata as content
        /// </summary>
        /// <param name="personMetadata">The person metadata to write.</param>
        internal void WritePersonMetadata(AtomPersonMetadata personMetadata)
        {
            Debug.Assert(personMetadata != null, "Person metadata must not be null.");

            // <atom:name>name of person</atom:name>
            // NOTE: write an empty element if no name is specified because the element is required.
            this.WriteElementWithTextContent(
                AtomConstants.AtomNamespacePrefix,
                AtomConstants.AtomPersonNameElementName,
                AtomConstants.AtomNamespace,
                personMetadata.Name);

            string uriString = personMetadata.UriFromEpm;

            if (uriString != null)
            {
                Debug.Assert(
                    personMetadata.Uri == null,
                    "If the internal UriFromEpm was used, then the Uri property must be left null. The merge between custom and EPM is probably wrong.");
            }
            else
            {
                Uri uri = personMetadata.Uri;
                if (uri != null)
                {
                    uriString = this.UriToUrlAttributeValue(uri);
                }
            }

            if (uriString != null)
            {
                this.WriteElementWithTextContent(
                    AtomConstants.AtomNamespacePrefix,
                    AtomConstants.AtomPersonUriElementName,
                    AtomConstants.AtomNamespace,
                    uriString);
            }

            string email = personMetadata.Email;

            if (email != null)
            {
                this.WriteElementWithTextContent(
                    AtomConstants.AtomNamespacePrefix,
                    AtomConstants.AtomPersonEmailElementName,
                    AtomConstants.AtomNamespace,
                    email);
            }
        }
 /// <summary>
 /// Visits an ATOM person metadata.
 /// </summary>
 /// <param name="atomPersonMetadata">The person metadata to visit.</param>
 protected override void VisitAtomPersonMetadata(AtomPersonMetadata atomPersonMetadata)
 {
     this.ValidateUri(atomPersonMetadata.Uri);
     base.VisitAtomPersonMetadata(atomPersonMetadata);
 }
        /// <summary>
        /// Reads a person (author/contributor) element.
        /// </summary>
        /// <returns>The person metadata object with the read values.</returns>
        /// <remarks>
        /// Pre-Condition:  XmlNodeType.Element (atom:contributor/atom:author) - the atom:author/atom:contributor element to read.
        /// Post-Condition: Any                                                - the node after the atom:author/atom:contributor element which was read.
        /// </remarks>
        protected AtomPersonMetadata ReadAtomPersonConstruct()
        {
            this.AssertXmlCondition(XmlNodeType.Element);
            Debug.Assert(
                (this.XmlReader.LocalName == AtomConstants.AtomAuthorElementName || this.XmlReader.LocalName == AtomConstants.AtomContributorElementName) &&
                this.XmlReader.NamespaceURI == AtomConstants.AtomNamespace,
                "Only atom:author or atom:contributor elements can be read by this method.");

            AtomPersonMetadata personMetadata = new AtomPersonMetadata();

            if (!this.XmlReader.IsEmptyElement)
            {
                // Move to the first child
                this.XmlReader.Read();

                do
                {
                    switch (this.XmlReader.NodeType)
                    {
                        case XmlNodeType.EndElement:
                            // End of the atom:author/atom:contributor element
                            continue;
                        case XmlNodeType.Element:
                            if (this.XmlReader.NamespaceEquals(this.AtomNamespace))
                            {
                                if (this.ReadAtomMetadata)
                                {
                                    switch (this.XmlReader.LocalName)
                                    {
                                        case AtomConstants.AtomPersonNameElementName:
                                            personMetadata.Name = this.ReadElementStringValue();
                                            continue;
                                        case AtomConstants.AtomPersonUriElementName:
                                            // NOTE: get the base URI here before we read the content as string; reading the content as string will move the 
                                            //       reader to the end element and thus we lose the xml:base definition on the element.
                                            Uri xmlBaseUri = this.XmlReader.XmlBaseUri;
                                            string textValue = this.ReadElementStringValue();
                                           
                                            if (this.ReadAtomMetadata)
                                            {
                                                personMetadata.Uri = this.ProcessUriFromPayload(textValue, xmlBaseUri);
                                            }

                                            continue;
                                        case AtomConstants.AtomPersonEmailElementName:
                                            personMetadata.Email = this.ReadElementStringValue();
                                            continue;
                                        default:
                                            break;
                                    }
                                }
                            }

                            break;
                        default:
                            break;
                    }

                    // Skip everything we haven't read yet.
                    this.XmlReader.Skip();
                }
                while (this.XmlReader.NodeType != XmlNodeType.EndElement);
            }

            // Read over the end element or the empty start element.
            this.AssertXmlCondition(true, XmlNodeType.EndElement);
            Debug.Assert(
                (this.XmlReader.LocalName == AtomConstants.AtomAuthorElementName || this.XmlReader.LocalName == AtomConstants.AtomContributorElementName) &&
                this.XmlReader.NamespaceURI == AtomConstants.AtomNamespace,
                "Only atom:author or atom:contributor elements can be read by this method.");
            this.XmlReader.Read();

            return personMetadata;
        }
        private static AtomPersonMetadata CreateAuthorMetadata(IEnumerable<XmlTreeAnnotation> children)
        {
            AtomPersonMetadata metadata = null;

            foreach (XmlTreeAnnotation epmTree in children)
            {
                if (epmTree.NamespaceName == TestAtomConstants.AtomNamespace)
                {
                    if (metadata == null)
                    {
                        metadata = new AtomPersonMetadata();
                    }

                    string localName = epmTree.LocalName;
                    if (localName == TestAtomConstants.AtomPersonNameElementName)
                    {
                        Debug.Assert(!epmTree.IsAttribute);
                        metadata.Name = epmTree.PropertyValue;
                    }
                    else if (localName == TestAtomConstants.AtomPersonUriElementName)
                    {
                        Debug.Assert(!epmTree.IsAttribute);
                        metadata.Uri = string.IsNullOrEmpty(epmTree.PropertyValue) ? null : new Uri(epmTree.PropertyValue);
                    }
                    else if (localName == TestAtomConstants.AtomPersonEmailElementName)
                    {
                        Debug.Assert(!epmTree.IsAttribute);
                        metadata.Email = epmTree.PropertyValue;
                    }
                }
            }

            return metadata;
        }
Example #7
0
        /// <summary>
        /// Reads a person (author/contributor) element.
        /// </summary>
        /// <returns>The person metadata object with the read values.</returns>
        /// <remarks>
        /// Pre-Condition:  XmlNodeType.Element (atom:contributor/atom:author) - the atom:author/atom:contributor element to read.
        /// Post-Condition: Any                                                - the node after the atom:author/atom:contributor element which was read.
        /// </remarks>
        protected AtomPersonMetadata ReadAtomPersonConstruct()
        {
            this.AssertXmlCondition(XmlNodeType.Element);
            Debug.Assert(
                (this.XmlReader.LocalName == AtomConstants.AtomAuthorElementName || this.XmlReader.LocalName == AtomConstants.AtomContributorElementName) &&
                this.XmlReader.NamespaceURI == AtomConstants.AtomNamespace,
                "Only atom:author or atom:contributor elements can be read by this method.");

            AtomPersonMetadata personMetadata = new AtomPersonMetadata();

            if (!this.XmlReader.IsEmptyElement)
            {
                // Move to the first child
                this.XmlReader.Read();

                do
                {
                    switch (this.XmlReader.NodeType)
                    {
                    case XmlNodeType.EndElement:
                        // End of the atom:author/atom:contributor element
                        continue;

                    case XmlNodeType.Element:
                        if (this.XmlReader.NamespaceEquals(this.AtomNamespace))
                        {
                            if (this.ReadAtomMetadata)
                            {
                                switch (this.XmlReader.LocalName)
                                {
                                case AtomConstants.AtomPersonNameElementName:
                                    personMetadata.Name = this.ReadElementStringValue();
                                    continue;

                                case AtomConstants.AtomPersonUriElementName:
                                    // NOTE: get the base URI here before we read the content as string; reading the content as string will move the
                                    //       reader to the end element and thus we lose the xml:base definition on the element.
                                    Uri    xmlBaseUri = this.XmlReader.XmlBaseUri;
                                    string textValue  = this.ReadElementStringValue();

                                    if (this.ReadAtomMetadata)
                                    {
                                        personMetadata.Uri = this.ProcessUriFromPayload(textValue, xmlBaseUri);
                                    }

                                    continue;

                                case AtomConstants.AtomPersonEmailElementName:
                                    personMetadata.Email = this.ReadElementStringValue();
                                    continue;

                                default:
                                    break;
                                }
                            }
                        }

                        break;

                    default:
                        break;
                    }

                    // Skip everything we haven't read yet.
                    this.XmlReader.Skip();
                }while (this.XmlReader.NodeType != XmlNodeType.EndElement);
            }

            // Read over the end element or the empty start element.
            this.AssertXmlCondition(true, XmlNodeType.EndElement);
            Debug.Assert(
                (this.XmlReader.LocalName == AtomConstants.AtomAuthorElementName || this.XmlReader.LocalName == AtomConstants.AtomContributorElementName) &&
                this.XmlReader.NamespaceURI == AtomConstants.AtomNamespace,
                "Only atom:author or atom:contributor elements can be read by this method.");
            this.XmlReader.Read();

            return(personMetadata);
        }
        public void EntryMetadataWriterTest()
        {
            const string testPublished = "2010-10-20T20:10:00Z";
            AtomTextConstruct testRights = new AtomTextConstruct { Text = "Copyright Data Fx team." };
            AtomTextConstruct testSummary = new AtomTextConstruct { Text = "Test summary." };
            AtomTextConstruct testTitle = new AtomTextConstruct { Text = "Test title" };
            const string testUpdated = "2010-11-01T00:04:00Z";
            const string testIcon = "http://odata.org/icon";
            const string testSourceId = "http://odata.org/id/random";
            const string testLogo = "http://odata.org/logo";
            AtomTextConstruct testSubtitle = new AtomTextConstruct { Text = "Test subtitle." };

            const string testAuthorName = "Test Author 1";
            const string testAuthorEmail = "*****@*****.**";
            const string testAuthorUri = "http://odata.org/authors/1";

            var testAuthors = new AtomPersonMetadata[]
                {
                    new AtomPersonMetadata()
                    {
                        Email = testAuthorEmail,
                        Name = testAuthorName,
                        Uri = new Uri(testAuthorUri)
                    }
                };

            var testAuthors2 = new AtomPersonMetadata[0];

            const string testCategoryTerm = "Test category 1 term";
            const string testCategoryLabel = "Test category 1 label";
            const string testCategoryScheme = "http://odata.org/categories/1";

            var testCategories = new AtomCategoryMetadata[]
                {
                    new AtomCategoryMetadata()
                    {
                        Term = testCategoryTerm,
                        Label = testCategoryLabel,
                        Scheme = testCategoryScheme
                    }
                };

            const string testContributorName = "Test Contributor 1";
            const string testContributorEmail = "*****@*****.**";
            const string testContributorUri = "http://odata.org/contributors/1";

            var testContributors = new AtomPersonMetadata[]
                {
                    new AtomPersonMetadata()
                    {
                        Email = testContributorEmail,
                        Name = testContributorName,
                        Uri = new Uri(testContributorUri)
                    }
                };

            const string testGeneratorName = "Test generator";
            const string testGeneratorUri = "http://odata.org/generator";
            const string testGeneratorVersion = "3.0";

            var testGenerator = new AtomGeneratorMetadata()
                {
                    Name = testGeneratorName,
                    Uri = new Uri(testGeneratorUri),
                    Version = testGeneratorVersion
                };

            const string testLinkRelation = "http://odata.org/links/1";
            const string testLinkTitle = "Test link 1";
            const string testLinkHref = "http://odata.org/links/1";
            const string testLinkHrefLang = "de-AT";
            int? testLinkLength = 999;
            const string testLinkMediaType = "image/png";

            var testLinks = new AtomLinkMetadata[] 
                {
                    new AtomLinkMetadata()
                    {
                        Relation = testLinkRelation,
                        Title = testLinkTitle,
                        Href = new Uri(testLinkHref),
                        HrefLang = testLinkHrefLang,
                        Length = testLinkLength,
                        MediaType = testLinkMediaType
                    }
                };

            AtomFeedMetadata testSource = new AtomFeedMetadata()
            {
                Authors = testAuthors,
                Categories = testCategories,
                Contributors = testContributors,
                Generator = testGenerator,
                Icon = new Uri(testIcon),
                SourceId = new Uri(testSourceId),
                Links = testLinks,
                Logo = new Uri(testLogo),
                Rights = testRights,
                Subtitle = testSubtitle,
                Title = testTitle,
                Updated = DateTimeOffset.Parse(testUpdated)
            };

            Func<string, Func<XElement, XElement>> fragmentExtractor = (localName) => (e) => e.Element(TestAtomConstants.AtomXNamespace + localName);

            // TODO, ckerer: specify an Id via metadata if the entry does not specify one; we first have to decide what rules
            //               we want to apply to merging of metadata and ODataLib OM data.
            var testCases = new[] {
                new { // specify an author via metadata
                    CustomizeMetadata = new Action<AtomEntryMetadata>(metadata => metadata.Authors = testAuthors),
                    Xml = string.Join(
                        "$(NL)",
                        @"<author xmlns=""" + TestAtomConstants.AtomNamespace + @""">",
                        @"  <name>" + testAuthorName + @"</name>",
                        @"  <uri>" + testAuthorUri + @"</uri>",
                        @"  <email>" + testAuthorEmail + @"</email>",
                        @"</author>"),
                    Extractor = fragmentExtractor(TestAtomConstants.AtomAuthorElementName)
                },
                new { // specify an empty author array via metadata
                    CustomizeMetadata = new Action<AtomEntryMetadata>(metadata => metadata.Authors = testAuthors2),
                    Xml = string.Join(
                        "$(NL)",
                        @"<author xmlns=""" + TestAtomConstants.AtomNamespace + @""">",
                        @"  <name />",
                        @"</author>"),
                    Extractor = fragmentExtractor(TestAtomConstants.AtomAuthorElementName)
                },
                new { // specify no authors via metadata
                    CustomizeMetadata = new Action<AtomEntryMetadata>(metadata => metadata.Authors = null),
                    Xml = string.Join(
                        "$(NL)",
                        @"<author xmlns=""" + TestAtomConstants.AtomNamespace + @""">",
                        @"$(Indent)<name />",
                        @"</author>"),
                    Extractor = fragmentExtractor(TestAtomConstants.AtomAuthorElementName)
                },
                new { // specify a category via metadata
                    CustomizeMetadata = new Action<AtomEntryMetadata>(metadata => metadata.Categories = testCategories),
                    Xml = @"<category term=""" + testCategoryTerm + @""" scheme=""" + testCategoryScheme + @""" label=""" + testCategoryLabel + @""" xmlns=""" + TestAtomConstants.AtomNamespace + @""" />",
                    Extractor = fragmentExtractor(TestAtomConstants.AtomCategoryElementName)
                },
                new { // specify a contributor via metadata
                    CustomizeMetadata = new Action<AtomEntryMetadata>(metadata => metadata.Contributors = testContributors),
                    Xml = string.Join(
                        "$(NL)",
                        @"<contributor xmlns=""" + TestAtomConstants.AtomNamespace + @""">",
                        @"  <name>" + testContributorName + @"</name>",
                        @"  <uri>" + testContributorUri + @"</uri>",
                        @"  <email>" + testContributorEmail + @"</email>",
                        @"</contributor>"),
                    Extractor = fragmentExtractor(TestAtomConstants.AtomContributorElementName)
                },
                new { // specify a link via metadata
                    CustomizeMetadata = new Action<AtomEntryMetadata>(metadata => metadata.Links = testLinks),
                    Xml = @"<link rel=""" + testLinkRelation + @""" type = """ + testLinkMediaType + @""" title=""" + testLinkTitle + @""" href=""" + testLinkHref + @""" hreflang=""" + testLinkHrefLang + @""" length=""" + testLinkLength + @"""  xmlns=""" + TestAtomConstants.AtomNamespace + @"""/>",
                    Extractor = new Func<XElement, XElement>(
                            (e) => e.Elements(TestAtomConstants.AtomXNamespace + TestAtomConstants.AtomLinkElementName)
                                    .Where(l => l.Attribute(TestAtomConstants.AtomLinkRelationAttributeName).Value != TestAtomConstants.AtomSelfRelationAttributeValue)
                                    .Single())
                },
                new { // specify a published date via metadata
                    CustomizeMetadata = new Action<AtomEntryMetadata>(metadata => metadata.Published = DateTimeOffset.Parse(testPublished)),
                    Xml = @"<published xmlns=""" + TestAtomConstants.AtomNamespace + @""">" + testPublished + @"</published>",
                    Extractor = fragmentExtractor(TestAtomConstants.AtomPublishedElementName)
                },
                new { // specify rights via metadata
                    CustomizeMetadata = new Action<AtomEntryMetadata>(metadata => metadata.Rights = testRights),
                    Xml = @"<rights type=""text"" xmlns=""" + TestAtomConstants.AtomNamespace + @""">" + testRights.Text + @"</rights>",
                    Extractor = fragmentExtractor(TestAtomConstants.AtomRightsElementName)
                },
                new { // specify a source via metadata
                    CustomizeMetadata = new Action<AtomEntryMetadata>(metadata => metadata.Source = testSource),
                    Xml = string.Join(
                        "$(NL)",
                        @"<source xmlns=""" + TestAtomConstants.AtomNamespace + @""">",
                        @"  <id>" + testSourceId + "</id>",
                        @"  <title type=""text"">" + testTitle.Text + @"</title>",
                        @"  <subtitle type=""text"">" + testSubtitle.Text + @"</subtitle>",
                        @"  <updated>" + testUpdated + @"</updated>",
                        @"  <link rel=""" + testLinkRelation + @""" type = """ + testLinkMediaType + @""" title=""" + testLinkTitle + @""" href=""" + testLinkHref + @""" hreflang=""" + testLinkHrefLang + @""" length=""" + testLinkLength + @"""/>",
                        @"  <category term=""" + testCategoryTerm + @""" scheme=""" + testCategoryScheme + @""" label=""" + testCategoryLabel + @""" />",
                        @"  <logo>" + testLogo + @"</logo>",
                        @"  <rights type=""text"">" + testRights.Text + @"</rights>",
                        @"  <contributor>",
                        @"    <name>" + testContributorName + @"</name>",
                        @"    <uri>" + testContributorUri + @"</uri>",
                        @"    <email>" + testContributorEmail + @"</email>",
                        @"  </contributor>",
                        @"  <generator uri=""" + testGeneratorUri + @""" version=""" +testGeneratorVersion + @""">" + testGeneratorName + @"</generator>",
                        @"  <icon>" + testIcon + @"</icon>",
                        @"  <author>",
                        @"    <name>" + testAuthorName + @"</name>",
                        @"    <uri>" + testAuthorUri + @"</uri>",
                        @"    <email>" + testAuthorEmail + @"</email>",
                        @"  </author>",
                        @"</source>"),
                    Extractor = fragmentExtractor(TestAtomConstants.AtomSourceElementName)
                },
                new { // specify default feed metadata as source
                    CustomizeMetadata = new Action<AtomEntryMetadata>(metadata => metadata.Source = new AtomFeedMetadata()),
                    Xml = string.Join(
                        "$(NL)",
                        @"<source xmlns=""" + TestAtomConstants.AtomNamespace + @""">",
                        @"  <id />",
                        @"  <title />",
                        @"  <updated />",
                        @"</source>"),
                    Extractor = new Func<XElement, XElement>(result => {
                        var source = fragmentExtractor(TestAtomConstants.AtomSourceElementName)(result);
                        // Remove the value of updates as it can't be reliably predicted
                        source.Element(TestAtomConstants.AtomXNamespace + TestAtomConstants.AtomUpdatedElementName).Nodes().Remove();
                        return source;
                    })
                },
                new { // specify a summary via metadata
                    CustomizeMetadata = new Action<AtomEntryMetadata>(metadata => metadata.Summary = testSummary),
                    Xml = @"<summary type=""text"" xmlns=""" + TestAtomConstants.AtomNamespace + @""">" + testSummary.Text + @"</summary>",
                    Extractor = fragmentExtractor(TestAtomConstants.AtomSummaryElementName)
                },
                new { // specify a title via metadata
                    CustomizeMetadata = new Action<AtomEntryMetadata>(metadata => metadata.Title = testTitle),
                    Xml = @"<title type=""text"" xmlns=""" + TestAtomConstants.AtomNamespace + @""">" + testTitle.Text + @"</title>",
                    Extractor = fragmentExtractor(TestAtomConstants.AtomTitleElementName)
                },
                new { // specify an updated date via metadata
                    CustomizeMetadata = new Action<AtomEntryMetadata>(metadata => metadata.Updated = DateTimeOffset.Parse(testUpdated)),
                    Xml = @"<updated xmlns=""" + TestAtomConstants.AtomNamespace + @""">" + testUpdated + @"</updated>",
                    Extractor = fragmentExtractor(TestAtomConstants.AtomUpdatedElementName)
                },
            };

            // Convert test cases to test descriptions
            IEnumerable<Func<ODataEntry>> entryCreators = new Func<ODataEntry>[]
                {
                    () => ObjectModelUtils.CreateDefaultEntry(),
                    () => ObjectModelUtils.CreateDefaultEntryWithAtomMetadata(),
                };
            var testDescriptors = testCases.SelectMany(testCase =>
                entryCreators.Select(entryCreator =>
                {
                    ODataEntry entry = entryCreator();
                    AtomEntryMetadata metadata = entry.Atom();
                    this.Assert.IsNotNull(metadata, "Expected default entry metadata on a default entry.");
                    testCase.CustomizeMetadata(metadata);
                    return new PayloadWriterTestDescriptor<ODataItem>(this.Settings, entry, testConfiguration =>
                        new AtomWriterTestExpectedResults(this.Settings.ExpectedResultSettings) { Xml = testCase.Xml, FragmentExtractor = testCase.Extractor });
                }));

            this.CombinatorialEngineProvider.RunCombinations(
                testDescriptors.PayloadCases(WriterPayloads.EntryPayloads),
                this.WriterTestConfigurationProvider.AtomFormatConfigurations,
                (testDescriptor, testConfiguration) =>
                {
                    testConfiguration = testConfiguration.Clone();
                    testConfiguration.MessageWriterSettings.SetServiceDocumentUri(ServiceDocumentUri);

                    TestWriterUtils.WriteAndVerifyODataPayload(testDescriptor, testConfiguration, this.Assert, this.Logger);
                });
        }
 /// <summary>
 /// Visits an ATOM person metadata.
 /// </summary>
 /// <param name="atomPersonMetadata">The person metadata to visit.</param>
 protected virtual void VisitAtomPersonMetadata(AtomPersonMetadata atomPersonMetadata)
 {
 }
        /// <summary>
        /// Adds a new contributor to feed metadata.
        /// </summary>
        /// <param name="feedMetadata">The feed metadata to add the contributor to.</param>
        /// <param name="contributorMetadata">The author metadata to add.</param>
        internal static void AddContributor(this AtomFeedMetadata feedMetadata, AtomPersonMetadata contributorMetadata)
        {
            Debug.Assert(feedMetadata != null, "feedMetadata != null");
            Debug.Assert(contributorMetadata != null, "contributorMetadata != null");

            feedMetadata.Contributors = feedMetadata.Contributors.ConcatToReadOnlyEnumerable("Contributors", contributorMetadata);
        }
        /// <summary>
        /// Adds a new author to feed metadata.
        /// </summary>
        /// <param name="feedMetadata">The feed metadata to add the author to.</param>
        /// <param name="authorMetadata">The author metadata to add.</param>
        internal static void AddAuthor(this AtomFeedMetadata feedMetadata, AtomPersonMetadata authorMetadata)
        {
            Debug.Assert(feedMetadata != null, "feedMetadata != null");
            Debug.Assert(authorMetadata != null, "authorMetadata != null");

            feedMetadata.Authors = feedMetadata.Authors.ConcatToReadOnlyEnumerable("Authors", authorMetadata);
        }
        /// <summary>
        /// Writes the specified start/end tags and the specified person metadata as content
        /// </summary>
        /// <param name="personMetadata">The person metadata to write.</param>
        internal void WritePersonMetadata(AtomPersonMetadata personMetadata)
        {
            Debug.Assert(personMetadata != null, "Person metadata must not be null.");

            // <atom:name>name of person</atom:name>
            // NOTE: write an empty element if no name is specified because the element is required.
            this.WriteElementWithTextContent(
                AtomConstants.AtomNamespacePrefix,
                AtomConstants.AtomPersonNameElementName,
                AtomConstants.AtomNamespace,
                personMetadata.Name);

            string uriString = personMetadata.UriFromEpm;
            if (uriString != null)
            {
                Debug.Assert(
                    personMetadata.Uri == null,
                    "If the internal UriFromEpm was used, then the Uri property must be left null. The merge between custom and EPM is probably wrong.");
            }
            else
            {
                Uri uri = personMetadata.Uri;
                if (uri != null)
                {
                    uriString = this.UriToUrlAttributeValue(uri);
                }
            }

            if (uriString != null)
            {
                this.WriteElementWithTextContent(
                    AtomConstants.AtomNamespacePrefix,
                    AtomConstants.AtomPersonUriElementName,
                    AtomConstants.AtomNamespace,
                    uriString);
            }

            string email = personMetadata.Email;
            if (email != null)
            {
                this.WriteElementWithTextContent(
                    AtomConstants.AtomNamespacePrefix,
                    AtomConstants.AtomPersonEmailElementName,
                    AtomConstants.AtomNamespace,
                    email);
            }
        }