Revert "Implement WebDAV detection via OPTIONS request with redirect support"

This reverts commit 76d46a8.

Author: sunkup

src/main/kotlin/at/bitfire/dav4jvm/DavResource.kt

@@ -68,8 +68,6 @@ open class DavResource @JvmOverloads constructor(
     companion object {
         const val MAX_REDIRECTS = 5
 
-        const val WEBDAV_VERSIONS = "1, 2, 3" // valid WebDAV versions
-
         const val HTTP_MULTISTATUS = 207
         val MIME_XML = "application/xml; charset=utf-8".toMediaType()
 
@@ -177,39 +175,6 @@ open class DavResource @JvmOverloads constructor(
         }
     }
 
-    /**
-     * Finds WebDAV capable location by sending OPTIONS request to this resource without HTTP
-     * compression (because some servers have broken compression for OPTIONS). Follows up
-     * to [MAX_REDIRECTS] redirects.
-     *
-     * @return the location of the WebDAV resource if it supports WebDAV, `null` otherwise
-     *
-     * @throws IOException on I/O error
-     * @throws HttpException on HTTP error
-     * @throws DavException on HTTPS -> HTTP redirect
-     */
-    @Throws(IOException::class, HttpException::class, DavException::class)
-    fun detectWebDav(): HttpUrl? = followRedirects {
-        httpClient.newCall(
-            Request.Builder()
-                .method("OPTIONS", null)
-                .header("Content-Length", "0")
-                .url(location)
-                .header("Accept-Encoding", "identity")      // disable compression
-                .build()
-        ).execute()
-    }.use { response ->
-        checkStatus(response)
-
-        // check whether WebDAV is supported
-        val davCapabilities = HttpUtils.listHeader(response, "DAV").map { it.trim() }.toSet()
-        val supportsWebDav = davCapabilities.any { it in WEBDAV_VERSIONS }
-        return if (supportsWebDav)
-            location
-        else
-            null
-    }
-
     /**
      * Sends a MOVE request to this resource. Follows up to [MAX_REDIRECTS] redirects.
      * Updates [location] on success.

src/test/kotlin/at/bitfire/dav4jvm/DavResourceTest.kt

@@ -484,51 +484,6 @@ class DavResourceTest {
         assertTrue(called)
     }
 
-    @Test
-    fun testDetectWebDav() {
-        val url = sampleUrl()
-        val dav = DavResource(httpClient, url)
-
-        // Without WebDAV
-        mockServer.enqueue(MockResponse()
-            .setResponseCode(HttpURLConnection.HTTP_OK)
-            .setHeader("DAV", "  0 ,, 4,5,6, hyperactive-access")
-        )
-        assertNull(dav.detectWebDav())
-
-        // With WebDAV
-        mockServer.enqueue(MockResponse()
-            .setResponseCode(HttpURLConnection.HTTP_OK)
-            .setHeader("DAV", " 1 ") // Class 1
-        )
-        assertEquals(url.encodedPath, dav.detectWebDav()?.encodedPath)
-        mockServer.enqueue(MockResponse()
-            .setResponseCode(HttpURLConnection.HTTP_OK)
-            .setHeader("DAV", "1, 2") // Class 2
-        )
-        assertEquals(url.encodedPath, dav.detectWebDav()?.encodedPath)
-        mockServer.enqueue(MockResponse()
-            .setResponseCode(HttpURLConnection.HTTP_OK)
-            .setHeader("DAV", " 1, 3 ") // Class 3
-        )
-        assertEquals(url.encodedPath, dav.detectWebDav()?.encodedPath)
-
-        // Follows redirects
-        mockServer.enqueue(MockResponse()
-            .setResponseCode(HttpURLConnection.HTTP_MOVED_TEMP)
-            .setHeader("Location", "/moved")
-        )
-        mockServer.enqueue(MockResponse()
-            .setResponseCode(HttpURLConnection.HTTP_MOVED_TEMP)
-            .setHeader("Location", "/redirected")
-        )
-        mockServer.enqueue(MockResponse()
-            .setResponseCode(HttpURLConnection.HTTP_OK)
-            .setHeader("DAV", "2")
-        )
-        assertEquals("/redirected", dav.detectWebDav()?.encodedPath)
-    }
-
     @Test
     fun testPropfindAndMultiStatus() {
         val url = sampleUrl()