Add support for the HttpClient (#148)

`Streamer` takes a new optional `HttpClient` dependency to handle HTTP requests.

CHANGELOG.md

@@ -4,7 +4,12 @@ All notable changes to this project will be documented in this file.
 
 **Warning:** Features marked as *experimental* may change or be removed in a future release without notice. Use with caution.
 
-<!-- ## [Unreleased] -->
+## [Unreleased]
+
+### Added
+
+* `Streamer` takes a new optional `HttpClient` dependency to handle HTTP requests.
+
 
 ## [2.0.0-beta.2]
 

r2-streamer/src/main/java/org/readium/r2/streamer/Streamer.kt

@@ -18,6 +18,7 @@ import org.readium.r2.shared.publication.asset.PublicationAsset
 import org.readium.r2.shared.util.Try
 import org.readium.r2.shared.util.archive.ArchiveFactory
 import org.readium.r2.shared.util.archive.DefaultArchiveFactory
+import org.readium.r2.shared.util.http.DefaultHttpClient
 import org.readium.r2.shared.util.logging.WarningLogger
 import org.readium.r2.shared.util.mediatype.MediaType
 import org.readium.r2.shared.util.pdf.PdfDocumentFactory
@@ -28,7 +29,7 @@ import org.readium.r2.streamer.parser.image.ImageParser
 import org.readium.r2.streamer.parser.pdf.PdfParser
 import org.readium.r2.streamer.parser.pdf.PdfiumPdfDocumentFactory
 import org.readium.r2.streamer.parser.readium.ReadiumWebPubParser
-import java.lang.Exception
+import kotlin.Exception
 
 internal typealias PublicationTry<SuccessT> = Try<SuccessT, Publication.OpeningException>
 
@@ -45,6 +46,7 @@ internal typealias PublicationTry<SuccessT> = Try<SuccessT, Publication.OpeningE
  * @param ignoreDefaultParsers When true, only parsers provided in parsers will be used.
  * @param archiveFactory Opens an archive (e.g. ZIP, RAR), optionally protected by credentials.
  * @param pdfFactory Parses a PDF document, optionally protected by password.
+ * @param httpClient Service performing HTTP requests.
  * @param onCreatePublication Called on every parsed [Publication.Builder]. It can be used to modify
  *   the [Manifest], the root [Fetcher] or the list of service factories of a [Publication].
  */
@@ -56,6 +58,7 @@ class Streamer constructor(
     private val contentProtections: List<ContentProtection> = emptyList(),
     private val archiveFactory: ArchiveFactory = DefaultArchiveFactory(),
     private val pdfFactory: PdfDocumentFactory = DefaultPdfDocumentFactory(context),
+    private val httpClient: DefaultHttpClient = DefaultHttpClient(),
     private val onCreatePublication: Publication.Builder.() -> Unit = {}
 ) {
 
@@ -121,7 +124,7 @@ class Streamer constructor(
                 } catch (e: Exception) {
                     throw Publication.OpeningException.ParsingFailed(e)
                 }
-            } ?: throw Publication.OpeningException.UnsupportedFormat
+            } ?: throw Publication.OpeningException.UnsupportedFormat(Exception("Cannot find a parser for this asset"))
 
         // Transform from the Content Protection.
         protectedAsset?.let { builder.apply(it.onCreatePublication) }
@@ -145,7 +148,7 @@ class Streamer constructor(
         listOf(
             EpubParser(),
             PdfParser(context, pdfFactory),
-            ReadiumWebPubParser(pdfFactory),
+            ReadiumWebPubParser(pdfFactory, httpClient),
             ImageParser(),
             AudioParser()
         )

r2-streamer/src/main/java/org/readium/r2/streamer/parser/readium/ReadiumWebPubParser.kt

@@ -9,29 +9,25 @@
 
 package org.readium.r2.streamer.parser.readium
 
-import android.content.Context
 import kotlinx.coroutines.runBlocking
-import org.json.JSONObject
 import org.readium.r2.shared.PdfSupport
 import org.readium.r2.shared.drm.DRM
-import org.readium.r2.shared.fetcher.ArchiveFetcher
-import org.readium.r2.shared.fetcher.Fetcher
-import org.readium.r2.shared.fetcher.FileFetcher
-import org.readium.r2.shared.fetcher.TransformingFetcher
+import org.readium.r2.shared.fetcher.*
 import org.readium.r2.shared.publication.Manifest
 import org.readium.r2.shared.publication.Publication
 import org.readium.r2.shared.publication.asset.FileAsset
 import org.readium.r2.shared.publication.asset.PublicationAsset
 import org.readium.r2.shared.publication.services.PerResourcePositionsService
 import org.readium.r2.shared.publication.services.locatorServiceFactory
 import org.readium.r2.shared.publication.services.positionsServiceFactory
+import org.readium.r2.shared.util.http.HttpClient
 import org.readium.r2.shared.util.logging.WarningLogger
 import org.readium.r2.shared.util.mediatype.MediaType
 import org.readium.r2.shared.util.pdf.PdfDocumentFactory
-import org.readium.r2.streamer.DefaultPdfDocumentFactory
 import org.readium.r2.streamer.PublicationParser
 import org.readium.r2.streamer.container.ContainerError
 import org.readium.r2.streamer.container.PublicationContainer
+import org.readium.r2.streamer.extensions.readAsJsonOrNull
 import org.readium.r2.streamer.fetcher.LcpDecryptor
 import org.readium.r2.streamer.parser.PubBox
 import org.readium.r2.streamer.parser.audio.AudioLocatorService
@@ -43,38 +39,46 @@ import java.io.FileNotFoundException
  * Parses any Readium Web Publication package or manifest, e.g. WebPub, Audiobook, DiViNa, LCPDF...
  */
 @OptIn(PdfSupport::class)
-class ReadiumWebPubParser(private val pdfFactory: PdfDocumentFactory? = null) : PublicationParser, org.readium.r2.streamer.parser.PublicationParser {
-
-    constructor(context: Context) : this(pdfFactory = DefaultPdfDocumentFactory(context))
+class ReadiumWebPubParser(
+    private val pdfFactory: PdfDocumentFactory?,
+    private val httpClient: HttpClient,
+) : PublicationParser, org.readium.r2.streamer.parser.PublicationParser {
 
     override suspend fun parse(
         asset: PublicationAsset,
         fetcher: Fetcher,
         warnings: WarningLogger?
     ): Publication.Builder? {
+        val mediaType = asset.mediaType()
 
-        if (!asset.mediaType().isReadiumWebPubProfile)
+        if (!mediaType.isReadiumWebPubProfile)
             return null
 
-        val manifest =
-            if (asset.mediaType().isRwpm) {
-                val manifestLink = fetcher.links().firstOrNull()
-                    ?: error("Empty fetcher.")
-                val manifestJson = fetcher.get(manifestLink).use {
-                    it.readAsString().getOrThrow()
-                }
-                Manifest.fromJSON(JSONObject(manifestJson))
+        val isPackage = !mediaType.isRwpm
+
+        val manifestJson =
+            if (isPackage) {
+                fetcher.readAsJsonOrNull("/manifest.json")
             } else {
-                val manifestLink = fetcher.links()
-                    .firstOrNull { it.href == "/manifest.json" }
-                    ?: error("Unable to find a manifest link.")
-                val manifestJson = fetcher.get(manifestLink).use {
-                    it.readAsString().getOrThrow()
-                }
-                Manifest.fromJSON(JSONObject(manifestJson), packaged = true)
+                // For a single manifest file, reads the first (and only) file in the fetcher.
+                fetcher.links().firstOrNull()
+                    ?.let { fetcher.readAsJsonOrNull(it.href) }
             }
-                ?: throw Exception("Failed to parse RWPM.")
+                ?: throw Exception("Manifest not found")
 
+        val manifest = Manifest.fromJSON(manifestJson, packaged = isPackage)
+            ?: throw Exception("Failed to parse the RWPM Manifest")
+
+        @Suppress("NAME_SHADOWING")
+        var fetcher = fetcher
+
+        // For a manifest, we discard the [fetcher] provided by the Streamer, because it was only
+        // used to read the manifest file. We use an [HttpFetcher] instead to serve the remote
+        // resources.
+        if (!isPackage) {
+            val baseUrl = manifest.linkWithRel("self")?.let { File(it.href).parent }
+            fetcher = HttpFetcher(httpClient, baseUrl)
+        }
 
         // Checks the requirements from the LCPDF specification.
         // https://readium.org/lcp-specs/notes/lcp-for-pdf.html

r2-streamer/src/test/java/org/readium/r2/streamer/parser/epub/EpubPositionsServiceTest.kt

@@ -426,7 +426,7 @@ class EpubPositionsServiceTest {
 
                 override suspend fun length() = findResource(link.href)
                     ?.let { Try.success(it.first) }
-                    ?: Try.failure(Resource.Exception.NotFound)
+                    ?: Try.failure(Resource.Exception.NotFound())
 
                 override suspend fun read(range: LongRange?): ResourceTry<ByteArray> = Try.success(ByteArray(0))