Some more cleanup

config/checkstyle/checkstyle.xml

@@ -0,0 +1,218 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!--
+SPDX-FileCopyrightText: 2021 Paul Schaub <info@pgpainless.org>
+
+SPDX-License-Identifier: CC0-1.0
+-->
+
+<!DOCTYPE module PUBLIC
+        "-//Puppy Crawl//DTD Check Configuration 1.3//EN"
+        "http://www.puppycrawl.com/dtds/configuration_1_3.dtd">
+<module name="Checker">
+
+    <!-- Suppressions -->
+    <module name="SuppressionFilter">
+        <property name="file" value="${config_loc}/suppressions.xml"/>
+    </module>
+
+    <module name="NewlineAtEndOfFile">
+        <property name="lineSeparator" value="lf"/>
+    </module>
+
+    <module name="RegexpSingleline">
+        <!--
+            Matches StringBuilder.append(String) calls where the
+            argument is a String of length one. Those should be replaced
+            with append(char) for performance reasons.
+
+            TODO: This could be more advanced in order to match also
+            - .append("\u1234")
+        -->
+        <property name="format" value="\.append\(&quot;(.|\\.)&quot;\)"/>
+        <property name="message" value="Don&apos;t use StringBuilder.append(String) when you can use StringBuilder.append(char). Solution: Replace double quotes of append&apos;s argument with single quotes."/>
+    </module>
+
+    <!-- Whitespace only lines -->
+    <module name="RegexpSingleline">
+        <property name="format" value="^\s+$"/>
+        <property name="message" value="Line containing only whitespace character(s)"/>
+    </module>
+
+    <!-- Mixed spaces/tabs -->
+    <module name="RegexpSingleline">
+        <!-- We use {2,} instead of + here to address the typical case where a file was written
+           with tabs but javadoc is causing '\t *' -->
+        <property name="format" value="^\t+ {2,}"/>
+        <property name="message" value="Line containing space(s) after tab(s)"/>
+    </module>
+
+    <!-- Trailing whitespaces -->
+    <module name="RegexpSingleline">
+        <!--
+            Explaining the following Regex
+
+                       \s+   $
+                        |    +- End of Line (2)
+                        +- At least one whitespace (1)
+
+            Rationale:
+            Matches trailing whitespace (2) in lines containing at least one (1) non-whitespace character
+        -->
+        <property name="format" value="\s+$"/>
+        <property name="message" value="Line containing trailing whitespace character(s)"/>
+    </module>
+
+    <!-- <module name="RegexpSingleline"> -->
+    <!--   <property name="format" value="fqdn"/> -->
+    <!-- </module> -->
+
+    <!-- Space after // -->
+    <module name="RegexpSingleline">
+        <property name="format" value="^\s*//[^\s]"/>
+        <property name="message" value="Comment start ('//') followed by non-space character. You would not continue after a punctuation without a space, would you?"/>
+    </module>
+
+    <module name="JavadocPackage">
+    </module>
+
+    <module name="TreeWalker">
+        <module name="SuppressionCommentFilter"/>
+        <module name="FinalClass"/>
+        <module name="UnusedImports">
+            <property name="processJavadoc" value="true"/>
+        </module>
+        <module name="AvoidStarImport"/>
+        <module name="IllegalImport"/>
+        <module name="RedundantImport"/>
+        <module name="RedundantModifier"/>
+        <module name="ModifierOrder"/>
+        <module name="UpperEll"/>
+        <module name="ArrayTypeStyle"/>
+        <module name="GenericWhitespace"/>
+        <module name="EmptyStatement"/>
+        <module name="PackageDeclaration"/>
+        <module name="LeftCurly"/>
+
+        <!-- Spaces instead of Tabs -->
+        <module name="RegexpSinglelineJava">
+            <property name="format" value="^\t+"/>
+            <property name="message" value="Indent must not use tab characters. Use space instead."/>
+        </module>
+
+        <module name="JavadocMethod">
+            <!-- TODO stricten those checks -->
+            <property name="scope" value="public"/>
+            <!--<property name="allowUndeclaredRTE" value="true"/>-->
+            <property name="allowMissingParamTags" value="true"/>
+            <property name="allowMissingThrowsTags" value="true"/>
+            <property name="allowMissingReturnTag" value="true"/>
+            <property name="allowMissingJavadoc" value="true"/>
+            <property name="suppressLoadErrors" value="true"/>
+        </module>
+
+        <module name="JavadocStyle">
+            <property name="scope" value="public"/>
+            <property name="checkEmptyJavadoc" value="true"/>
+            <property name="checkHtml" value="false"/>
+        </module>
+
+        <module name="ParenPad">
+        </module>
+
+        <!-- Whitespace after key tokens -->
+        <module name="NoWhitespaceAfter">
+            <property name="tokens" value="INC
+										 , DEC
+										 , UNARY_MINUS
+										 , UNARY_PLUS
+										 , BNOT, LNOT
+										 , DOT
+										 , ARRAY_DECLARATOR
+										 , INDEX_OP
+										 "/>
+        </module>
+
+        <!-- Whitespace after key words -->
+        <module name="WhitespaceAfter">
+            <property name="tokens" value="TYPECAST
+										 , LITERAL_IF
+										 , LITERAL_ELSE
+										 , LITERAL_WHILE
+										 , LITERAL_DO
+										 , LITERAL_FOR
+										 , DO_WHILE
+										 "/>
+        </module>
+
+        <module name="WhitespaceAround">
+            <property
+                    name="ignoreEnhancedForColon"
+                    value="false"
+            />
+            <!-- Currently disabled tokens: LCURLY, RCURLY, WILDCARD_TYPE, GENERIC_START, GENERIC_END -->
+            <property
+                    name="tokens"
+                    value="ASSIGN
+					 , ARRAY_INIT
+					 , BAND
+					 , BAND_ASSIGN
+					 , BOR
+					 , BOR_ASSIGN
+					 , BSR
+					 , BSR_ASSIGN
+					 , BXOR
+					 , BXOR_ASSIGN
+					 , COLON
+					 , DIV
+					 , DIV_ASSIGN
+					 , DO_WHILE
+					 , EQUAL
+					 , GE
+					 , GT
+					 , LAMBDA
+					 , LAND
+					 , LE
+					 , LITERAL_CATCH
+					 , LITERAL_DO
+					 , LITERAL_ELSE
+					 , LITERAL_FINALLY
+					 , LITERAL_FOR
+					 , LITERAL_IF
+					 , LITERAL_RETURN
+					 , LITERAL_SWITCH
+					 , LITERAL_SYNCHRONIZED
+					 , LITERAL_TRY
+					 , LITERAL_WHILE
+					 , LOR
+					 , LT
+					 , MINUS
+					 , MINUS_ASSIGN
+					 , MOD
+					 , MOD_ASSIGN
+					 , NOT_EQUAL
+					 , PLUS
+					 , PLUS_ASSIGN
+					 , QUESTION
+					 , SL
+					 , SLIST
+					 , SL_ASSIGN
+					 , SR
+					 , SR_ASSIGN
+					 , STAR
+					 , STAR_ASSIGN
+					 , LITERAL_ASSERT
+					 , TYPE_EXTENSION_AND
+					 "/>
+        </module>
+
+        <!--
+        <module name="CustomImportOrder">
+            <property name="customImportOrderRules"
+                      value="STATIC###STANDARD_JAVA_PACKAGE###SPECIAL_IMPORTS###THIRD_PARTY_PACKAGE"/>
+            <property name="specialImportsRegExp" value="^org\.org.pgpainless.core\.org.pgpainless.core"/>
+            <property name="sortImportsInGroupAlphabetically" value="true"/>
+            <property name="separateLineBetweenGroups" value="true"/>
+        </module>
+        -->
+    </module>
+</module>

config/checkstyle/suppressions.xml

@@ -0,0 +1,19 @@
+<?xml version="1.0"?>
+<!--
+SPDX-FileCopyrightText: 2021 Paul Schaub <info@pgpainless.org>
+
+SPDX-License-Identifier: CC0-1.0
+-->
+
+<!DOCTYPE suppressions PUBLIC
+        "-//Puppy Crawl//DTD Suppressions 1.1//EN"
+        "http://www.puppycrawl.com/dtds/suppressions_1_1.dtd">
+<suppressions>
+    <!-- GenericWhitespace has some problems with false postive, leave
+it disabled until gradle uses a checkstyle version where this is fixed
+-->
+    <suppress checks="GenericWhitespace"
+              files="Protocol.java" />
+    <!-- Suppress JavadocPackage in the test packages -->
+    <suppress checks="JavadocPackage" files="[\\/]test[\\/]"/>
+</suppressions>

vks-java/build.gradle

@@ -16,8 +16,10 @@ dependencies {
     testImplementation "org.junit.jupiter:junit-jupiter-api:$junitVersion"
     testRuntimeOnly "org.junit.jupiter:junit-jupiter-engine:$junitVersion"
 
-    api("org.pgpainless:pgp-certificate-store:0.1.0")
+    implementation("org.bouncycastle:bcutil-jdk15on:1.70")
-    api("org.pgpainless:pgpainless-core:1.1.4")
+
+    // api("org.pgpainless:pgp-certificate-store:0.1.0")
+    // api("org.pgpainless:pgpainless-core:1.1.4")
 
     // @Nonnull, @Nullable...
     implementation "com.google.code.findbugs:jsr305:3.0.2"

vks-java/src/main/java/pgp/vks/client/RequestVerify.java

@@ -4,19 +4,53 @@
 
 package pgp.vks.client;
 
-import pgp.vks.client.v1.dto.VerificationResponse;
-
 import java.io.IOException;
 import java.util.Arrays;
 import java.util.List;
+import java.util.Map;
 
 public interface RequestVerify {
 
-    default VerificationResponse forEmailAddresses(List<String> emailAddresses, String uploadToken)
+    default ForEmailAddresses forEmailAddress(String emailAddress) {
-            throws IOException {
+        return forEmailAddresses(emailAddress);
-        return forEmailAddresses(emailAddresses, uploadToken, Arrays.asList("en_US", "en_GB"));
     }
 
-    VerificationResponse forEmailAddresses(List<String> emailAddresses, String uploadToken, List<String> locale)
+    ForEmailAddresses forEmailAddresses(String... emailAddresses);
-            throws IOException;
+
+    interface ForEmailAddresses {
+
+        default Response execute(String token) throws IOException {
+            return execute(token, Arrays.asList("en_US", "en_GB"));
+        }
+
+        Response execute(String token, List<String> locale) throws IOException;
+
+    }
+
+    class Response {
+
+        private final String keyFingerprint;
+        private final Map<String, Status> status;
+        private final String token;
+
+        public Response(String keyFingerprint,
+                        Map<String, Status> status,
+                        String token) {
+            this.keyFingerprint = keyFingerprint;
+            this.status = status;
+            this.token = token;
+        }
+
+        public String getKeyFingerprint() {
+            return keyFingerprint;
+        }
+
+        public Map<String, Status> getStatus() {
+            return status;
+        }
+
+        public String getToken() {
+            return token;
+        }
+    }
 }

vks-java/src/main/java/pgp/vks/client/Status.java

@@ -0,0 +1,28 @@
+// SPDX-FileCopyrightText: 2022 Paul Schaub <vanitasvitae@fsfe.org>
+//
+// SPDX-License-Identifier: Apache-2.0
+
+package pgp.vks.client;
+
+public enum Status {
+
+    /**
+     * User-ID is not published.
+     */
+    unpublished,
+
+    /**
+     * User-ID is published.
+     */
+    published,
+
+    /**
+     * User-ID is revoked.
+     */
+    revoked,
+
+    /**
+     * A verification mail for the User-ID was requested, but the verification is still pending.
+     */
+    pending
+}

vks-java/src/main/java/pgp/vks/client/Upload.java

@@ -4,14 +4,65 @@
 
 package pgp.vks.client;
 
-import pgp.vks.client.v1.dto.UploadResponse;
-
 import javax.annotation.Nonnull;
 import java.io.IOException;
 import java.io.InputStream;
+import java.util.HashMap;
+import java.util.Map;
 
 public interface Upload {
 
-    UploadResponse cert(@Nonnull InputStream certInStream) throws IOException;
+    /**
+     * Upload a certificate to the key server.
+     * The <pre>certInStream</pre> can either contain the binary, or the ASCII armored representation of a transferable
+     * public key (certificate).
+     *
+     * @param certInStream inputStream containing the certificate
+     * @return server response
+     * @throws IOException in case of an IO error
+     */
+    Response cert(@Nonnull InputStream certInStream) throws IOException;
 
+    class Response {
+
+        private final String keyFingerprint;
+        private final Map<String, Status> status;
+        private final String token;
+
+        public Response(String keyFingerprint,
+                        Map<String, Status> status,
+                        String token) {
+            this.keyFingerprint = keyFingerprint;
+            this.status = status;
+            this.token = token;
+        }
+
+        /**
+         * Return the fingerprint of the uploaded certificate.
+         *
+         * @return fingerprint
+         */
+        public String getKeyFingerprint() {
+            return keyFingerprint;
+        }
+
+        /**
+         * Return an access token which, for a limited time, can be used to request verifications (see {@link RequestVerify}).
+         *
+         * @return access token
+         */
+        public String getToken() {
+            return token;
+        }
+
+        /**
+         * Return a map containing the {@link Status} of each of the keys addresses.
+         *
+         * @return status map
+         */
+        public Map<String, Status> getStatus() {
+            return new HashMap<>(status);
+        }
+    }
 }
+

vks-java/src/main/java/pgp/vks/client/exception/package-info.java

@@ -2,7 +2,7 @@
 //
 // SPDX-License-Identifier: Apache-2.0
 
-package pgp.vks.client.impl.v1.dummy_vks;
+/**
-
+ * Exception classes.
-public class DummyVks {
+ */
-}
+package pgp.vks.client.exception;

vks-java/src/main/java/pgp/vks/client/package-info.java

@@ -0,0 +1,8 @@
+// SPDX-FileCopyrightText: 2022 Paul Schaub <vanitasvitae@fsfe.org>
+//
+// SPDX-License-Identifier: Apache-2.0
+
+/**
+ * Client API for communicating with Verifying Key Servers.
+ */
+package pgp.vks.client;

vks-java/src/main/java/pgp/vks/client/v1/dto/ErrorResponseDto.java

@@ -6,11 +6,11 @@ package pgp.vks.client.v1.dto;
 
 import com.fasterxml.jackson.annotation.JsonProperty;
 
-public class ErrorResponse {
+public class ErrorResponseDto {
 
     private final String error;
 
-    public ErrorResponse(@JsonProperty("error") String error) {
+    public ErrorResponseDto(@JsonProperty("error") String error) {
         this.error = error;
     }
 

vks-java/src/main/java/pgp/vks/client/v1/dto/UploadRequestDto.java

@@ -7,22 +7,33 @@ package pgp.vks.client.v1.dto;
 import com.fasterxml.jackson.annotation.JsonProperty;
 import org.bouncycastle.util.Arrays;
 import org.bouncycastle.util.encoders.Base64;
+import org.bouncycastle.util.io.Streams;
 
-import java.nio.charset.StandardCharsets;
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.nio.charset.Charset;
 
-public class UploadRequest {
+public class UploadRequestDto {
 
-    private static final byte[] ARMOR_HEADER = "-----BEGIN PGP PUBLIC KEY BLOCK-----".getBytes(StandardCharsets.UTF_8);
+    private static final byte[] ARMOR_HEADER = "-----BEGIN PGP PUBLIC KEY BLOCK-----".getBytes(Charset.forName("UTF8"));
 
     private final String keytext;
 
-    public UploadRequest(@JsonProperty("keytext") String keytext) {
+    public UploadRequestDto(@JsonProperty("keytext") String keytext) {
         this.keytext = keytext;
     }
 
-    public static UploadRequest fromBytes(byte[] keytext) {
+    public static UploadRequestDto fromInputStream(InputStream certInStream) throws IOException {
+        ByteArrayOutputStream certBuf = new ByteArrayOutputStream();
+        Streams.pipeAll(certInStream, certBuf);
+        certInStream.close();
+        return fromBytes(certBuf.toByteArray());
+    }
+
+    public static UploadRequestDto fromBytes(byte[] keytext) {
         String armoredOrBase64 = new String(base64IfNecessary(keytext));
-        return new UploadRequest(armoredOrBase64);
+        return new UploadRequestDto(armoredOrBase64);
     }
 
     private static byte[] base64IfNecessary(byte[] certBytes) {

vks-java/src/main/java/pgp/vks/client/v1/dto/UploadResponseDto.java

@@ -4,19 +4,20 @@
 
 package pgp.vks.client.v1.dto;
 
-import com.fasterxml.jackson.annotation.JsonIgnore;
 import com.fasterxml.jackson.annotation.JsonProperty;
+import pgp.vks.client.Status;
+import pgp.vks.client.Upload;
 
 import java.util.HashMap;
 import java.util.Map;
 
-public class UploadResponse {
+public class UploadResponseDto {
 
     private final String key_fpr;
     private final Map<String, Status> status;
     private final String token;
 
-    public UploadResponse(@JsonProperty("key_fpr") String key_fpr,
+    public UploadResponseDto(@JsonProperty("key_fpr") String key_fpr,
                              @JsonProperty("status") Map<String, Status> status,
                              @JsonProperty("token") String token) {
         this.key_fpr = key_fpr;
@@ -38,4 +39,8 @@ public class UploadResponse {
     public Map<String, Status> getStatus() {
         return new HashMap<>(status);
     }
+
+    public Upload.Response toEntity() {
+        return new Upload.Response(getKeyFingerprint(), getStatus(), getToken());
+    }
 }

vks-java/src/main/java/pgp/vks/client/v1/dto/VerificationRequestDto.java

@@ -8,13 +8,13 @@ import com.fasterxml.jackson.annotation.JsonProperty;
 
 import java.util.List;
 
-public class VerificationRequest {
+public class VerificationRequestDto {
 
     private final String token;
     private final List<String> addresses;
     private final List<String> locale;
 
-    public VerificationRequest(@JsonProperty("token") String token,
+    public VerificationRequestDto(@JsonProperty("token") String token,
                                   @JsonProperty("addresses") List<String> addresses,
                                   @JsonProperty("locale") List<String> locale) {
         this.token = token;

vks-java/src/main/java/pgp/vks/client/v1/dto/VerificationResponseDto.java

@@ -5,16 +5,18 @@
 package pgp.vks.client.v1.dto;
 
 import com.fasterxml.jackson.annotation.JsonProperty;
+import pgp.vks.client.RequestVerify;
+import pgp.vks.client.Status;
 
 import java.util.Map;
 
-public class VerificationResponse {
+public class VerificationResponseDto {
 
     private final String key_fpr;
     private final Map<String, Status> status;
     private final String token;
 
-    public VerificationResponse(@JsonProperty("key_fpr") String key_fpr,
+    public VerificationResponseDto(@JsonProperty("key_fpr") String key_fpr,
                                    @JsonProperty("status") Map<String, Status> status,
                                    @JsonProperty("token") String token) {
         this.key_fpr = key_fpr;
@@ -36,4 +38,8 @@ public class VerificationResponse {
     public Map<String, Status> getStatus() {
         return status;
     }
+
+    public RequestVerify.Response toEntity() {
+        return new RequestVerify.Response(getKeyFingerprint(), getStatus(), getToken());
+    }
 }

vks-java/src/main/java/pgp/vks/client/v1/dto/package-info.java

@@ -2,11 +2,7 @@
 //
 // SPDX-License-Identifier: Apache-2.0
 
+/**
+ * JSON DTOs for v1 API.
+ */
 package pgp.vks.client.v1.dto;
-
-public enum Status {
-    unpublished,
-    published,
-    revoked,
-    pending
-}

vks-java/src/main/java/pgp/vks/client/v1/impl/RequestVerifyImpl.java

@@ -7,15 +7,17 @@ package pgp.vks.client.v1.impl;
 import com.fasterxml.jackson.databind.ObjectMapper;
 import pgp.vks.client.RequestVerify;
 import pgp.vks.client.exception.CertCannotBePublishedException;
-import pgp.vks.client.v1.dto.ErrorResponse;
+import pgp.vks.client.v1.dto.ErrorResponseDto;
-import pgp.vks.client.v1.dto.VerificationResponse;
+import pgp.vks.client.v1.dto.VerificationRequestDto;
-import pgp.vks.client.v1.dto.VerificationRequest;
+import pgp.vks.client.v1.dto.VerificationResponseDto;
 
+import javax.annotation.Nonnull;
 import javax.net.ssl.HttpsURLConnection;
 import java.io.IOException;
 import java.io.InputStream;
 import java.io.OutputStream;
 import java.net.URL;
+import java.util.Arrays;
 import java.util.List;
 
 public class RequestVerifyImpl implements RequestVerify {
@@ -28,9 +30,26 @@ public class RequestVerifyImpl implements RequestVerify {
     }
 
     @Override
-    public VerificationResponse forEmailAddresses(List<String> emailAddresses, String token, List<String> locale)
+    public ForEmailAddresses forEmailAddresses(String... emailAddresses) {
-            throws IOException {
+        if (emailAddresses == null || emailAddresses.length == 0) {
-        VerificationRequest request = new VerificationRequest(token, emailAddresses, locale);
+            throw new IllegalArgumentException("At least one email address is required.");
+        }
+        List<String> emailList = Arrays.asList(emailAddresses);
+
+        return new ForEmailAddressesImpl(emailList);
+    }
+
+    private class ForEmailAddressesImpl implements ForEmailAddresses {
+
+        private final List<String> emailAddresses;
+
+        ForEmailAddressesImpl(@Nonnull List<String> emailList) {
+            this.emailAddresses = emailList;
+        }
+
+        @Override
+        public Response execute(String token, List<String> locale) throws IOException {
+            VerificationRequestDto request = new VerificationRequestDto(token, emailAddresses, locale);
 
             URL url = api.postRequestVerify();
             HttpsURLConnection connection = (HttpsURLConnection) url.openConnection();
@@ -47,12 +66,13 @@ public class RequestVerifyImpl implements RequestVerify {
             InputStream responseIn;
             if (status >= 400) {
                 responseIn = connection.getErrorStream();
-            ErrorResponse errorResponse = json.readValue(responseIn, ErrorResponse.class);
+                ErrorResponseDto errorResponse = json.readValue(responseIn, ErrorResponseDto.class);
-            throw new CertCannotBePublishedException(errorResponse.getError() + (status));
+                throw new CertCannotBePublishedException(errorResponse.getError() + " (" + status + ")");
             } else {
                 responseIn = connection.getInputStream();
-            VerificationResponse response = json.readValue(responseIn, VerificationResponse.class);
+                VerificationResponseDto response = json.readValue(responseIn, VerificationResponseDto.class);
-            return response;
+                return response.toEntity();
+            }
         }
     }
 }

vks-java/src/main/java/pgp/vks/client/v1/impl/UploadImpl.java

@@ -4,19 +4,15 @@
 
 package pgp.vks.client.v1.impl;
 
-import com.fasterxml.jackson.annotation.JsonAutoDetect;
-import com.fasterxml.jackson.annotation.PropertyAccessor;
 import com.fasterxml.jackson.databind.ObjectMapper;
-import org.bouncycastle.util.io.Streams;
 import pgp.vks.client.Upload;
 import pgp.vks.client.exception.CertCannotBePublishedException;
-import pgp.vks.client.v1.dto.UploadRequest;
+import pgp.vks.client.v1.dto.ErrorResponseDto;
-import pgp.vks.client.v1.dto.ErrorResponse;
+import pgp.vks.client.v1.dto.UploadRequestDto;
-import pgp.vks.client.v1.dto.UploadResponse;
+import pgp.vks.client.v1.dto.UploadResponseDto;
 
 import javax.annotation.Nonnull;
 import javax.net.ssl.HttpsURLConnection;
-import java.io.ByteArrayOutputStream;
 import java.io.IOException;
 import java.io.InputStream;
 import java.io.OutputStream;
@@ -32,12 +28,8 @@ public class UploadImpl implements Upload {
     }
 
     @Override
-    public UploadResponse cert(@Nonnull InputStream certInStream) throws IOException {
+    public Response cert(@Nonnull InputStream certInStream) throws IOException {
-        ByteArrayOutputStream certBuf = new ByteArrayOutputStream();
+        UploadRequestDto request = UploadRequestDto.fromInputStream(certInStream);
-        Streams.pipeAll(certInStream, certBuf);
-        certInStream.close();
-
-        UploadRequest request = UploadRequest.fromBytes(certBuf.toByteArray());
 
         URL url = api.postUpload();
         HttpsURLConnection connection = (HttpsURLConnection) url.openConnection();
@@ -46,22 +38,20 @@ public class UploadImpl implements Upload {
         connection.setDoOutput(true);
 
         OutputStream out = connection.getOutputStream();
-        byte[] requestBody = json.writeValueAsBytes(request);
+        json.writeValue(out, request);
-        out.write(requestBody);
         out.flush();
         out.close();
 
         int status = connection.getResponseCode();
-        System.out.println(status);
         InputStream responseIn;
         if (status >= 400) {
             responseIn = connection.getErrorStream();
-            ErrorResponse errorResponse = json.readValue(responseIn, ErrorResponse.class);
+            ErrorResponseDto errorResponse = json.readValue(responseIn, ErrorResponseDto.class);
             throw new CertCannotBePublishedException(errorResponse.getError() + (status));
         } else {
             responseIn = connection.getInputStream();
-            UploadResponse response = json.readValue(responseIn, UploadResponse.class);
+            UploadResponseDto dto = json.readValue(responseIn, UploadResponseDto.class);
-            return response;
+            return dto.toEntity();
         }
     }
 }

vks-java/src/main/java/pgp/vks/client/v1/impl/package-info.java

@@ -0,0 +1,8 @@
+// SPDX-FileCopyrightText: 2022 Paul Schaub <vanitasvitae@fsfe.org>
+//
+// SPDX-License-Identifier: Apache-2.0
+
+/**
+ * Implementations of interfaces for API v1.
+ */
+package pgp.vks.client.v1.impl;

vks-java/src/main/java/pgp/vks/client/v1/package-info.java

@@ -0,0 +1,8 @@
+// SPDX-FileCopyrightText: 2022 Paul Schaub <vanitasvitae@fsfe.org>
+//
+// SPDX-License-Identifier: Apache-2.0
+
+/**
+ * Implementation of API v1.
+ */
+package pgp.vks.client.v1;

vks-java/src/test/java/pgp/vks/client/v1/dto/ErrorResponseDtoTest.java

@@ -0,0 +1,28 @@
+// SPDX-FileCopyrightText: 2022 Paul Schaub <vanitasvitae@fsfe.org>
+//
+// SPDX-License-Identifier: Apache-2.0
+
+package pgp.vks.client.v1.dto;
+
+import com.fasterxml.jackson.core.JsonProcessingException;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+public class ErrorResponseDtoTest {
+
+    private static final ObjectMapper json = new ObjectMapper();
+
+    @Test
+    public void testSerializeDeserialize() throws JsonProcessingException {
+        String errorMessage = "Certificate cannot be parsed.";
+        ErrorResponseDto dto = new ErrorResponseDto(errorMessage);
+        assertEquals(errorMessage, dto.getError());
+
+        String val = json.writeValueAsString(dto);
+        dto = json.readValue(val, ErrorResponseDto.class);
+
+        assertEquals(errorMessage, dto.getError());
+    }
+}

vks-java/src/test/java/pgp/vks/client/v1/dto/UploadRequestDtoTest.java

@@ -2,17 +2,16 @@
 //
 // SPDX-License-Identifier: Apache-2.0
 
-package pgp.vks.client.impl.v1.dto;
+package pgp.vks.client.v1.dto;
 
 import com.fasterxml.jackson.core.JsonProcessingException;
 import com.fasterxml.jackson.databind.ObjectMapper;
 import org.bouncycastle.util.encoders.Base64;
 import org.junit.jupiter.api.Test;
-import pgp.vks.client.v1.dto.UploadRequest;
 
 import static org.junit.jupiter.api.Assertions.assertEquals;
 
-public class UploadRequestTest {
+public class UploadRequestDtoTest {
 
     private static final String TEST_CERT_ARMORED = "-----BEGIN PGP PUBLIC KEY BLOCK-----\n" +
             "Comment: 9DF2 C3FE 6F69 A3EE DBD5  FB81 69E8 A788 A36E 7BFD\n" +
@@ -71,21 +70,23 @@ public class UploadRequestTest {
 
     @Test
     public void testSerializeDeserializeArmoredCert() throws JsonProcessingException {
-        UploadRequest request = new UploadRequest(TEST_CERT_ARMORED);
+        UploadRequestDto request = new UploadRequestDto(TEST_CERT_ARMORED);
 
         String val = json.writeValueAsString(request);
-        request = json.readValue(val, UploadRequest.class);
+        request = json.readValue(val, UploadRequestDto.class);
 
         assertEquals(TEST_CERT_ARMORED, request.getKeyText());
     }
 
     @Test
     public void testSerializeDeserializeBase64() throws JsonProcessingException {
+        // raw bytes
         byte[] rawCert = Base64.decode(TEST_CERT_BASE64);
-        UploadRequest request = UploadRequest.fromBytes(rawCert);
+
+        UploadRequestDto request = UploadRequestDto.fromBytes(rawCert);
 
         String val = json.writeValueAsString(request);
-        request = json.readValue(val, UploadRequest.class);
+        request = json.readValue(val, UploadRequestDto.class);
 
         assertEquals(TEST_CERT_BASE64, request.getKeyText());
     }

vks-java/src/test/java/pgp/vks/client/v1/dto/UploadResponseTest.java

@@ -2,13 +2,12 @@
 //
 // SPDX-License-Identifier: Apache-2.0
 
-package pgp.vks.client.impl.v1.dto;
+package pgp.vks.client.v1.dto;
 
 import com.fasterxml.jackson.core.JsonProcessingException;
 import com.fasterxml.jackson.databind.ObjectMapper;
 import org.junit.jupiter.api.Test;
-import pgp.vks.client.v1.dto.Status;
+import pgp.vks.client.Status;
-import pgp.vks.client.v1.dto.UploadResponse;
 
 import java.util.HashMap;
 import java.util.Map;
@@ -27,10 +26,10 @@ public class UploadResponseTest {
         statusMap.put("hello@mail.world", Status.unpublished);
         String token = "t0k3n5tr1n9";
 
-        UploadResponse response = new UploadResponse(fingerprint, statusMap, token);
+        UploadResponseDto response = new UploadResponseDto(fingerprint, statusMap, token);
 
         String val = json.writeValueAsString(response);
-        response = json.readValue(val, UploadResponse.class);
+        response = json.readValue(val, UploadResponseDto.class);
 
         assertEquals(fingerprint, response.getKeyFingerprint());
         assertEquals(statusMap, response.getStatus());

vks-java/src/test/java/pgp/vks/client/v1/dto/VerificationRequestDtoTest.java

@@ -0,0 +1,39 @@
+// SPDX-FileCopyrightText: 2022 Paul Schaub <vanitasvitae@fsfe.org>
+//
+// SPDX-License-Identifier: Apache-2.0
+
+package pgp.vks.client.v1.dto;
+
+import com.fasterxml.jackson.core.JsonProcessingException;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import org.junit.jupiter.api.Test;
+
+import java.util.Arrays;
+import java.util.List;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+public class VerificationRequestDtoTest {
+
+    private static final ObjectMapper json = new ObjectMapper();
+
+    @Test
+    public void testSerializationDeserialization() throws JsonProcessingException {
+        String token = "thisisalongtokenstring";
+        List<String> addresses = Arrays.asList("alice@pgpainless.org", "vanitasvitae@fsfe.org", "Ed_Snowden@lavabit.com");
+        List<String> locale = Arrays.asList("de_DE", "de_CH");
+
+        VerificationRequestDto dto = new VerificationRequestDto(token, addresses, locale);
+        assertEquals(token, dto.getToken());
+        assertEquals(addresses, dto.getAddresses());
+        assertEquals(locale, dto.getLocale());
+
+        String val = json.writeValueAsString(dto);
+
+        dto = json.readValue(val, VerificationRequestDto.class);
+        assertEquals(token, dto.getToken());
+        assertEquals(addresses, dto.getAddresses());
+        assertEquals(locale, dto.getLocale());
+    }
+
+}

vks-java/src/test/java/pgp/vks/client/v1/dto/VerificationResponseDtoTest.java

@@ -0,0 +1,42 @@
+// SPDX-FileCopyrightText: 2022 Paul Schaub <vanitasvitae@fsfe.org>
+//
+// SPDX-License-Identifier: Apache-2.0
+
+package pgp.vks.client.v1.dto;
+
+import com.fasterxml.jackson.core.JsonProcessingException;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import org.junit.jupiter.api.Test;
+import pgp.vks.client.Status;
+
+import java.util.HashMap;
+import java.util.Map;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+public class VerificationResponseDtoTest {
+
+    private static final ObjectMapper json = new ObjectMapper();
+
+    @Test
+    public void testSerializationDeserialization() throws JsonProcessingException {
+        String fingerprint = "1EBF5F15850C540B3142F1584BDD496D4C6C5F25";
+        Map<String, Status> status = new HashMap<>();
+        status.put("XXX@riseup.net", Status.published);
+        status.put("l.p@riseup.net", Status.unpublished);
+        status.put("laura@riseup.net", Status.pending);
+        status.put("poitras@gmail.com", Status.revoked);
+        String token = "incrediblylongandoverlytideoustotypetokenstring";
+
+        VerificationResponseDto dto = new VerificationResponseDto(fingerprint, status, token);
+        assertEquals(fingerprint, dto.getKeyFingerprint());
+        assertEquals(status, dto.getStatus());
+        assertEquals(token, dto.getToken());
+
+        String val = json.writeValueAsString(dto);
+        dto = json.readValue(val, VerificationResponseDto.class);
+        assertEquals(fingerprint, dto.getKeyFingerprint());
+        assertEquals(status, dto.getStatus());
+        assertEquals(token, dto.getToken());
+    }
+}

vks-java/src/test/java/pgp/vks/client/v1/impl/URLMapperTest.java

@@ -2,18 +2,17 @@
 //
 // SPDX-License-Identifier: Apache-2.0
 
-package pgp.vks.client.impl.v1;
+package pgp.vks.client.v1.impl;
 
 import org.junit.jupiter.api.BeforeAll;
 import org.junit.jupiter.api.Test;
-import pgp.vks.client.v1.impl.URLMapper;
 
 import java.net.MalformedURLException;
 import java.net.URL;
 
 import static org.junit.jupiter.api.Assertions.assertEquals;
 
-public class V1APITest {
+public class URLMapperTest {
 
     private static URLMapper api;
 

vks-java/src/test/java/pgp/vks/client/v1/impl/VKSTest.java

@@ -2,45 +2,37 @@
 //
 // SPDX-License-Identifier: Apache-2.0
 
-package pgp.vks.client.impl.v1;
+package pgp.vks.client.v1.impl;
 
+import org.bouncycastle.util.Arrays;
 import org.bouncycastle.util.io.Streams;
 import org.junit.jupiter.api.BeforeAll;
 import org.junit.jupiter.api.Test;
+import pgp.vks.client.RequestVerify;
+import pgp.vks.client.Upload;
 import pgp.vks.client.VKS;
+import pgp.vks.client.exception.CertCannotBePublishedException;
 import pgp.vks.client.exception.CertNotFoundException;
-import pgp.vks.client.v1.dto.VerificationResponse;
-import pgp.vks.client.v1.impl.VKSImpl;
-import pgp.vks.client.v1.dto.UploadResponse;
 
 import java.io.ByteArrayInputStream;
+import java.io.ByteArrayOutputStream;
 import java.io.IOException;
 import java.io.InputStream;
+import java.net.MalformedURLException;
 import java.nio.charset.StandardCharsets;
-import java.util.Collections;
+import java.util.Random;
 
 import static org.junit.jupiter.api.Assertions.assertEquals;
 import static org.junit.jupiter.api.Assertions.assertThrows;
+import static org.junit.jupiter.api.Assertions.assertTrue;
 
 public class VKSTest {
 
     private static VKS vks;
 
     @BeforeAll
-    static void prepare() {
+    static void prepare() throws MalformedURLException {
-        vks = VKSImpl.keysDotOpenPgpDotOrg();
+        vks = new VKSImpl("https://testing2.keys.openpgp.org");
-    }
-
-    @Test
-    public void testGetByFingerprint() throws IOException {
-        InputStream inputStream = vks.get().byFingerprint("7F9116FEA90A5983936C7CFAA027DB2F3E1E118A");
-        Streams.pipeAll(inputStream, System.out);
-    }
-
-    @Test
-    public void testGetByFingerprint_inexistent() {
-        assertThrows(CertNotFoundException.class, () ->
-                vks.get().byFingerprint("0000000000000000000000000000000000000000"));
     }
 
     @Test
@@ -77,16 +69,75 @@ public class VKSTest {
                 "YA3TLiYiZbEM\n" +
                 "=QRwY\n" +
                 "-----END PGP PUBLIC KEY BLOCK-----\n";
+        System.out.println(keyArmored);
         String keyFingerprint = "57417147D0C8B548220A36A60BAAB05A087768D3";
 
-        UploadResponse uploadResponse = vks.upload().cert(new ByteArrayInputStream(keyArmored.getBytes(StandardCharsets.UTF_8)));
+        Upload.Response uploadResponse = vks.upload().cert(new ByteArrayInputStream(keyArmored.getBytes(StandardCharsets.UTF_8)));
         assertEquals(keyFingerprint, uploadResponse.getKeyFingerprint());
 
-        VerificationResponse verifyResponse = vks.requestVerification().forEmailAddresses(
+        RequestVerify.Response verifyResponse = vks.requestVerification()
-                Collections.singletonList("test123asdasd@byom.de"),
+                .forEmailAddress("test123asdasd@byom.de")
-                uploadResponse.getToken(),
+                .execute(uploadResponse.getToken());
-                Collections.singletonList("de_DE"));
 
         assertEquals(keyFingerprint, verifyResponse.getKeyFingerprint());
     }
+
+    @Test
+    public void testGetByKeyId() throws IOException {
+        long keyId = 1620429777827217382L; // subkey id of the cert
+        byte[] expectedHeader = ("-----BEGIN PGP PUBLIC KEY BLOCK-----\n" +
+                "Comment: 5741 7147 D0C8 B548 220A  36A6 0BAA B05A 0877 68D3")
+                .getBytes(StandardCharsets.UTF_8);
+        InputStream in = vks.get().byKeyId(keyId);
+        ByteArrayOutputStream out = new ByteArrayOutputStream();
+        Streams.pipeAll(in, out);
+        in.close();
+
+        assertTrue(Arrays.areEqual(
+                expectedHeader, 0, expectedHeader.length, out.toByteArray(), 0, expectedHeader.length));
+    }
+
+    @Test
+    public void testGetByFingerprint() throws IOException {
+        byte[] expectedHeader = ("-----BEGIN PGP PUBLIC KEY BLOCK-----\n" +
+                "Comment: 5741 7147 D0C8 B548 220A  36A6 0BAA B05A 0877 68D3")
+                .getBytes(StandardCharsets.UTF_8);
+        InputStream in = vks.get().byFingerprint("57417147D0C8B548220A36A60BAAB05A087768D3");
+        ByteArrayOutputStream out = new ByteArrayOutputStream();
+        Streams.pipeAll(in, out);
+        in.close();
+
+        assertTrue(Arrays.areEqual(
+                expectedHeader, 0, expectedHeader.length, out.toByteArray(), 0, expectedHeader.length));
+    }
+
+    @Test
+    public void testGetByEmail() throws IOException {
+        byte[] expectedHeader = ("-----BEGIN PGP PUBLIC KEY BLOCK-----\n" +
+                "Comment: 7F91 16FE A90A 5983 936C  7CFA A027 DB2F 3E1E 118A")
+                .getBytes(StandardCharsets.UTF_8);
+
+        InputStream in = vks.get().byEmail("vanitasvitae@fsfe.org");
+        ByteArrayOutputStream out = new ByteArrayOutputStream();
+        Streams.pipeAll(in, out);
+        in.close();
+
+        assertTrue(Arrays.areEqual(
+                expectedHeader, 0, expectedHeader.length, out.toByteArray(), 0, expectedHeader.length));
+    }
+
+    @Test
+    public void testGetByFingerprint_inexistent() {
+        assertThrows(CertNotFoundException.class, () ->
+                vks.get().byFingerprint("0000000000000000000000000000000000000000"));
+    }
+
+    @Test
+    public void testUploadBrokenKey() {
+        byte[] buf = new byte[4096];
+        new Random().nextBytes(buf);
+
+        assertThrows(CertCannotBePublishedException.class, () ->
+                vks.upload().cert(new ByteArrayInputStream(buf)));
+    }
 }