feat(model-server): /repositories/{repository}/branches outputs json if accepted

Author: abstraktor

model-server-api/src/commonMain/kotlin/org/modelix/model/server/api/BranchInfo.kt

@@ -0,0 +1,8 @@
+package org.modelix.model.server.api
+
+import kotlinx.serialization.Serializable
+import kotlin.js.JsExport
+
+@JsExport
+@Serializable
+data class BranchInfo(val id: String, val versionHash: String)

model-server-openapi/specifications/model-server-v2.yaml

@@ -249,7 +249,14 @@ paths:
             type: string
       responses:
         "200":
-          $ref: '#/components/responses/200'
+          description: OK
+          content:
+            text/plain:
+              schema:
+                type: string
+            application/json:
+              schema:
+                $ref: "#/components/schemas/BranchesWithHashes"
         default:
           $ref: '#/components/responses/GeneralError'
   /repositories/{repository}/branches/{branch}:
@@ -764,3 +771,15 @@ components:
           type: string
           description: Unix timestamp
         author: { type: string }
+    BranchesWithHashes:
+      type: array
+      items:
+        type: object
+        properties:
+          id:
+            type: string
+          versionHash:
+            type: string
+        required:
+          - id
+          - versionHash

model-server/src/main/kotlin/org/modelix/model/server/handlers/ModelReplicationServer.kt

@@ -54,6 +54,7 @@ import org.modelix.model.lazy.RepositoryId
 import org.modelix.model.operations.OTBranch
 import org.modelix.model.persistent.HashUtil
 import org.modelix.model.server.ModelServerPermissionSchema
+import org.modelix.model.server.api.BranchInfo
 import org.modelix.model.server.api.RepositoryConfig
 import org.modelix.model.server.api.v2.ImmutableObjectsStream
 import org.modelix.model.server.api.v2.VersionDelta
@@ -114,14 +115,30 @@ class ModelReplicationServer(
     }
 
     override suspend fun RoutingContext.getRepositoryBranches(repository: String) {
-        call.respondText(
-            @OptIn(RequiresTransaction::class)
-            runRead { repositoriesManager.getBranchNames(repositoryId(repository)) }
+        @OptIn(RequiresTransaction::class)
+        val branchNames = runRead {
+            repositoriesManager.getBranchNames(repositoryId(repository))
                 .filter { call.hasPermission(ModelServerPermissionSchema.repository(repository).branch(it).list) }
-                .joinToString("\n"),
-        )
+        }
+        if (acceptsJson()) {
+            call.respond<List<BranchInfo>>(
+                @OptIn(RequiresTransaction::class)
+                runRead {
+                    branchNames.mapNotNull { branchName ->
+                        val branchRef = repositoryId(repository).getBranchReference(branchName)
+                        val versionHash = repositoriesManager.getVersionHash(branchRef)
+                        versionHash?.let { BranchInfo(branchName, it) }
+                    }
+                },
+            )
+        } else {
+            call.respondText(branchNames.joinToString("\n"))
+        }
     }
 
+    private fun RoutingContext.acceptsJson(): Boolean =
+        call.request.acceptItems().any { ContentType.parse(it.value).match(ContentType.Application.Json) }
+
     override suspend fun RoutingContext.getRepositoryBranchDelta(
         repository: String,
         branch: String,

model-server/src/test/kotlin/org/modelix/model/server/handlers/ModelReplicationServerTest.kt

@@ -48,6 +48,7 @@ import org.modelix.model.client2.readVersionDelta
 import org.modelix.model.client2.runWrite
 import org.modelix.model.client2.useVersionStreamFormat
 import org.modelix.model.lazy.RepositoryId
+import org.modelix.model.server.api.BranchInfo
 import org.modelix.model.server.api.v2.VersionDeltaStream
 import org.modelix.model.server.api.v2.VersionDeltaStreamV2
 import org.modelix.model.server.installDefaultServerPlugins
@@ -169,6 +170,71 @@ class ModelReplicationServerTest {
         }
     }
 
+    @Test
+    fun `fetch branches as plain`() {
+        val repositoryId = RepositoryId("repo1")
+
+        runWithTestModelServer { _, fixture ->
+            @OptIn(RequiresTransaction::class)
+            fixture.repositoriesManager.getTransactionManager().runWrite {
+                val version = fixture.repositoriesManager.createRepository(repositoryId, null)
+                fixture.repositoriesManager.forcePush(
+                    branch = repositoryId.getBranchReference("change-request/1"),
+                    newVersionHash = version.getContentHash(),
+                )
+            }
+
+            val response = client.get {
+                url {
+                    appendPathSegments("v2", "repositories", repositoryId.id, "branches")
+                }
+            }
+
+            assertEquals(HttpStatusCode.OK, response.status)
+            assertContains(response.bodyAsText(), "master")
+        }
+    }
+
+    @Test
+    fun `fetch branches as json`() {
+        val repositoryId = RepositoryId("repo1")
+
+        runWithTestModelServer { _, fixture ->
+
+            // Arrange
+            @OptIn(RequiresTransaction::class)
+            val initialVersion = fixture.repositoriesManager.getTransactionManager().runWrite {
+                fixture.repositoriesManager.createRepository(repositoryId, null)
+                    .also {
+                        fixture.repositoriesManager.forcePush(
+                            branch = repositoryId.getBranchReference("change-requests/1"),
+                            newVersionHash = it.getContentHash(),
+                        )
+                    }
+            }
+
+            // Act
+            val client = jsonClient()
+            val response = client.get {
+                accept(ContentType.Application.Json)
+                url {
+                    appendPathSegments("v2", "repositories", repositoryId.id, "branches")
+                }
+            }
+
+            // Assert
+            assertEquals(HttpStatusCode.OK, response.status)
+            response.shouldHaveContentType(ContentType.Application.Json.withCharset(Charsets.UTF_8))
+            assertEquals(
+                response.body<List<BranchInfo>>(),
+                listOf(
+                    BranchInfo("change-requests/1", initialVersion.getContentHash()),
+                    BranchInfo("master", initialVersion.getContentHash()),
+                ),
+            )
+        }
+    }
+
     @Test
     fun `responds with 400 when deleting from an invalid repository ID`() {
         runWithTestModelServer { _, _ ->
@@ -434,13 +500,7 @@ class ModelReplicationServerTest {
             fixture.repositoriesManager.getTransactionManager().runWrite {
                 fixture.repositoriesManager.createRepository(repositoryId, null)
             }
-            val client = createClient {
-                install(ContentNegotiation) {
-                    json()
-                    register(branchV1ContentType, KotlinxSerializationConverter(DefaultJson))
-                }
-            }
-
+            val client = jsonClient()
             val response = client.get {
                 url {
                     appendPathSegments("v2", "repositories", repositoryId.id, "branches", "master")
@@ -545,6 +605,13 @@ class ModelReplicationServerTest {
     }
 }
 
+private fun ApplicationTestBuilder.jsonClient(): HttpClient = createClient {
+    install(ContentNegotiation) {
+        json()
+        register(ContentType.Application.Json, KotlinxSerializationConverter(DefaultJson))
+    }
+}
+
 fun <T> Flow<T>.assertNotEmpty(additionalMessage: () -> String = { "" }): Flow<T> {
     return onEmpty { throw IllegalArgumentException("At least one element was expected. " + additionalMessage()) }
 }