OpdsFeed

app/src/main/kotlin/com/ustadmobile/zim2xapi/App.kt

@@ -12,11 +12,11 @@ import com.github.ajalt.clikt.parameters.types.file
 import com.github.ajalt.clikt.parameters.types.int
 import com.ustadmobile.zim2xapi.Client.client
 import com.ustadmobile.zim2xapi.Client.json
+import com.ustadmobile.zim2xapi.models.Topic
 import com.ustadmobile.zim2xapi.utils.SysPathUtil
 import kotlinx.serialization.json.Json
 import okhttp3.OkHttpClient
 import java.io.File
-import java.io.FileNotFoundException
 
 object Client {
     // Create a single OkHttpClient instance
@@ -111,11 +111,21 @@ class DownloadTopic : CliktCommand(name = "convert") {
 
     val keepTempFiles by option("-k","-keep-temp", help = "Keep temporary files").flag()
 
+    val endpoints by option("--endpoint", "-e")
+        .convert { it.split(",") }
+        .default(
+            listOf(
+                "https://kolibri-demo.learningequality.org",
+                "https://kolibri-catalog-en.learningequality.org"
+            )
+        )
+
     override fun run() {
 
         val channelId = channelId
         val topicId = topicId
         val zimFile = zimFile
+        var topics: List<Topic> = emptyList()
 
         val createdZimFile: File = zimFile ?: if (channelId != null && topicId != null) {
 
@@ -130,6 +140,8 @@ class DownloadTopic : CliktCommand(name = "convert") {
 
                 val kolbir2zimProcess = ProcessBuilderUseCase(kolibri2zimPath)
 
+                topics =  ListKolibriTopicsUseCase(client, json).invoke(channelId, topicId, endpoints)
+
                 DownloadKolibriZimUseCase(kolbir2zimProcess).invoke(
                     channelId,
                     topicId,
@@ -163,13 +175,15 @@ class DownloadTopic : CliktCommand(name = "convert") {
             // fix any exceptions found in the folder
             FixExtractZimExceptionsUseCase(zimDumpProcess).invoke(createdZimFile, extractedZimFolder)
 
+
             // create the xApi zip file
             val xapiFile = CreateXapiFileUseCase(zimDumpProcess, AddxAPIStatementUseCase(), json).invoke(
                 extractedZimFolder,
                 outputDir,
                 fileName,
                 createdZimFile,
-                passingGrade
+                passingGrade,
+                topics
             )
 
             echo("Process completed. Output filename: ${xapiFile.name}")

app/src/main/kotlin/com/ustadmobile/zim2xapi/CreateXapiFileUseCase.kt

@@ -1,7 +1,14 @@
 package com.ustadmobile.zim2xapi
 
 import com.ustadmobile.zim2xapi.models.ActivityDefinition
+import com.ustadmobile.zim2xapi.models.Topic
 import com.ustadmobile.zim2xapi.models.XapiObject
+import com.ustadmobile.zim2xapi.models.opdsfeed.OpdsFeed
+import com.ustadmobile.zim2xapi.models.opdsfeed.OpdsFeedMetadata
+import com.ustadmobile.zim2xapi.models.opdsfeed.OpdsWebMetadata
+import com.ustadmobile.zim2xapi.models.opdsfeed.ReadiumLink
+import com.ustadmobile.zim2xapi.models.opdsfeed.OpdsWebPublication
+import com.ustadmobile.zim2xapi.models.opdsfeed.OpdsWebPublicationLink
 import kotlinx.serialization.json.Json
 import org.jsoup.Jsoup
 import java.io.File
@@ -10,6 +17,7 @@ import java.io.FileOutputStream
 import java.io.PrintWriter
 import java.util.zip.ZipEntry
 import java.util.zip.ZipOutputStream
+import kotlin.reflect.typeOf
 
 class CreateXapiFileUseCase(
     private val zimDumpProcess: ProcessBuilderUseCase,
@@ -22,7 +30,8 @@ class CreateXapiFileUseCase(
         outputFolder: File,
         fileName: String,
         zimFile: File,
-        passingGrade: Int
+        passingGrade: Int,
+        topics: List<Topic>
     ): File {
 
         val indexHtml = File(zimFolder, INDEX_HTML)
@@ -54,7 +63,7 @@ class CreateXapiFileUseCase(
             )
         }
 
-        val xapiObjectJsonFile = File(zimFolder, "xapiobject.json")
+        val xapiObjectJsonFile = File(zimFolder, XAPI_OBJECT_JSON)
         xapiObjectJsonFile.writeText(
             json.encodeToString(
                 XapiObject.serializer(), XapiObject(
@@ -68,6 +77,100 @@ class CreateXapiFileUseCase(
             )
         )
 
+        val path = zimFolder.absolutePath.toString()
+        val topicId = path.split("/").last()
+        val assetResources = generateResourceLinks(zimFolder, topicId)
+
+        val opdsFeedJsonFile = File(zimFolder, OPDS_JSON)
+        opdsFeedJsonFile.writeText(
+            json.encodeToString(
+                OpdsFeed.serializer(), OpdsFeed(
+                    metadata = OpdsFeedMetadata(
+                        title = title,
+                        description = description
+                    ),
+                    links = listOf(
+                        ReadiumLink(
+                            href = "$topicId/$topicId",
+                            title = title,
+                        )
+                    ),
+                    navigation = listOf(
+                        ReadiumLink(
+                            href = "$topicId/$topicId.json",
+                            title = title
+                        ),
+                    )
+                )
+            )
+        )
+
+        val publicationLinks = topics.map { subTopic ->
+            OpdsWebPublication(
+                links = listOf(
+                    OpdsWebPublicationLink(
+                        rel = SELF_LINK,
+                        href = "$topicId/${subTopic.id}.json"
+                    ),
+                ),
+                context = "",
+                metadata = OpdsWebMetadata(
+                    title = subTopic.title,
+                    description = subTopic.description,
+                    identifier = subTopic.id
+                ),
+            )
+        }
+
+        val topicJsonFile = File(zimFolder, "${topicId}.json")
+        topicJsonFile.writeText(
+            json.encodeToString(
+                OpdsFeed.serializer(), OpdsFeed(
+                    metadata = OpdsFeedMetadata(
+                        title = title,
+                        description = description
+                    ),
+                    links = listOf(
+                        ReadiumLink(
+                            href = "$topicId/$topicId.json",
+                            title = title,
+                        )
+                    ),
+                    publications = publicationLinks
+                )
+            )
+        )
+
+        topics.forEach { subTopic ->
+            val subTopicJsonFile = File(zimFolder, "${subTopic.id}.json")
+            subTopicJsonFile.writeText(
+                json.encodeToString(
+                    OpdsWebPublication.serializer(),
+                    OpdsWebPublication(
+                        context = "",
+                        metadata = OpdsWebMetadata(
+                            title = subTopic.title,
+                            description = subTopic.description,
+                            identifier = subTopic.id
+                        ),
+                        links = listOf(
+                            OpdsWebPublicationLink(
+                                rel = SELF_LINK,
+                                href = "$topicId/${subTopic.id}"
+                            ),
+                            OpdsWebPublicationLink(
+                                rel = ACQUISITION_LINK,
+                                href = "$topicId/$INDEX_HTML",
+                                type = "text/html"
+                            )
+                        ),
+                        resources = assetResources
+                    )
+                )
+            )
+        }
+
+
         addXApi.invoke(zimFolder, passingGrade)
 
         val xapiFile = File(outputFolder, "$fileName.zip")
@@ -87,11 +190,37 @@ class CreateXapiFileUseCase(
         return xapiFile
     }
 
+    private fun generateResourceLinks(
+        zimFolder: File,
+        topic: String
+    ): List<OpdsWebPublicationLink> {
+        val assetsFolder = File(zimFolder, ASSESTS)
+        if (!assetsFolder.exists() || !assetsFolder.isDirectory) return emptyList()
+
+        return assetsFolder.walk()
+            .filter { it.isFile }
+            .map { file ->
+                val relativePath = zimFolder.toPath().relativize(file.toPath()).toString()
+                OpdsWebPublicationLink(
+                    href = "$topic/$relativePath",
+                )
+            }
+            .toList()
+    }
+
     companion object {
 
         const val TINCAN_XML = "tincan.xml"
         const val INDEX_HTML = "index.html"
 
+        const val XAPI_OBJECT_JSON = "xapiobject.json"
+        const val OPDS_JSON = "opds.json"
+
+        const val ASSESTS = "assets"
+
+        const val SELF_LINK = "self"
+        const val ACQUISITION_LINK = "http://opds-spec.org/acquisition/open-access"
+
         const val ACTIVITY_TYPE = "http://adlnet.gov/expapi/activities/module"
 
     }

app/src/main/kotlin/com/ustadmobile/zim2xapi/ListKolibriTopicsUseCase.kt

@@ -19,6 +19,22 @@ class ListKolibriTopicsUseCase(
         displayTopicInfo(topic)
     }
 
+    operator fun invoke(
+        channelId: String,
+        topicId: String,
+        endpoints: List<String>
+    ): List<Topic> {
+        val rootTopic = fetchTopic(topicId, endpoints)
+
+        val topics = mutableListOf<Topic>()
+
+        rootTopic.children?.results?.forEach { child ->
+            flattenTopics(child, topics)
+        }
+
+        return topics
+    }
+
     private fun displayTopicInfo(topic: Topic, depth: Int = 0) {
         val indent = "  ".repeat(depth)
         println("$indent- ${topic.title} (ID: ${topic.id}, Kind: ${topic.kind}, Leaf: ${topic.is_leaf})")
@@ -27,7 +43,12 @@ class ListKolibriTopicsUseCase(
             displayTopicInfo(child, depth + 1)
         }
     }
-
+    private fun flattenTopics(topic: Topic, list: MutableList<Topic>) {
+        list.add(topic)
+        topic.children?.results?.forEach { child ->
+            flattenTopics(child, list)
+        }
+    }
     private fun fetchTopic(id: String, endpoints: List<String>): Topic {
         // expecting one url to throw a 404 or an error
         endpoints.forEach {base ->

app/src/main/kotlin/com/ustadmobile/zim2xapi/models/opdsfeed/OpdsFeed.kt

@@ -0,0 +1,11 @@
+package com.ustadmobile.zim2xapi.models.opdsfeed
+
+import kotlinx.serialization.Serializable
+
+@Serializable
+data class OpdsFeed(
+    val metadata: OpdsFeedMetadata,
+    val links: List<ReadiumLink>,
+    val publications: List<OpdsWebPublication>? = null,
+    val navigation: List<ReadiumLink>? = null,
+)

app/src/main/kotlin/com/ustadmobile/zim2xapi/models/opdsfeed/OpdsFeedMetaData.kt

@@ -0,0 +1,9 @@
+package com.ustadmobile.zim2xapi.models.opdsfeed
+
+import kotlinx.serialization.Serializable
+
+@Serializable
+data class OpdsFeedMetadata(
+    val title: String,
+    val description: String? = null
+)

app/src/main/kotlin/com/ustadmobile/zim2xapi/models/opdsfeed/OpdsPublication.kt

@@ -0,0 +1,11 @@
+package com.ustadmobile.zim2xapi.models.opdsfeed
+
+import kotlinx.serialization.Serializable
+
+@Serializable
+data class OpdsPublication(
+    val metadata: ReadiumMetadata,
+    val links: List<ReadiumLink>,
+    val images: List<ReadiumLink>? = null,
+)
+

app/src/main/kotlin/com/ustadmobile/zim2xapi/models/opdsfeed/OpdsWebMetadata.kt

@@ -0,0 +1,14 @@
+package com.ustadmobile.zim2xapi.models.opdsfeed
+
+import kotlinx.serialization.Serializable
+
+@Serializable
+data class OpdsWebMetadata(
+    val type: String? = null,
+    val title: String,
+    val author: String? = null,
+    val identifier: String,
+    val language: String? = null,
+    val modified: String? = null,
+    val description: String? = null
+)

app/src/main/kotlin/com/ustadmobile/zim2xapi/models/opdsfeed/OpdsWebPublication.kt

@@ -0,0 +1,13 @@
+package com.ustadmobile.zim2xapi.models.opdsfeed
+
+import kotlinx.serialization.Serializable
+
+@Serializable
+data class OpdsWebPublication(
+    val context: String,
+    val metadata: OpdsWebMetadata,
+    val links: List<OpdsWebPublicationLink>,
+    val readingOrder: List<OpdsWebPublicationLink> = emptyList(),
+    val resources: List<OpdsWebPublicationLink> = emptyList()
+)
+

app/src/main/kotlin/com/ustadmobile/zim2xapi/models/opdsfeed/OpdsWebPublicationLink.kt

@@ -0,0 +1,10 @@
+package com.ustadmobile.zim2xapi.models.opdsfeed
+
+import kotlinx.serialization.Serializable
+
+@Serializable
+data class OpdsWebPublicationLink(
+    val rel: String? = null,
+    val href: String,
+    val type: String? = null
+)

app/src/main/kotlin/com/ustadmobile/zim2xapi/models/opdsfeed/ReadiumLink.kt

@@ -0,0 +1,9 @@
+package com.ustadmobile.zim2xapi.models.opdsfeed
+
+import kotlinx.serialization.Serializable
+
+@Serializable
+data class ReadiumLink(
+    val href: String,
+    val title: String? = null
+)

app/src/main/kotlin/com/ustadmobile/zim2xapi/models/opdsfeed/ReadiumMetadata.kt

@@ -0,0 +1,9 @@
+package com.ustadmobile.zim2xapi.models.opdsfeed
+
+import kotlinx.serialization.Serializable
+
+@Serializable
+data class ReadiumMetadata(
+    val title: String,
+    val description: String? = null
+)