Create stripe api endpoint for apple pay donations

service/src/main/java/org/whispersystems/textsecuregcm/WhisperServerConfiguration.java

@@ -22,6 +22,7 @@ import org.whispersystems.textsecuregcm.configuration.AwsAttachmentsConfiguratio
 import org.whispersystems.textsecuregcm.configuration.CdnConfiguration;
 import org.whispersystems.textsecuregcm.configuration.DatabaseConfiguration;
 import org.whispersystems.textsecuregcm.configuration.DirectoryConfiguration;
+import org.whispersystems.textsecuregcm.configuration.DonationConfiguration;
 import org.whispersystems.textsecuregcm.configuration.DynamoDbConfiguration;
 import org.whispersystems.textsecuregcm.configuration.GcmConfiguration;
 import org.whispersystems.textsecuregcm.configuration.GcpAttachmentsConfiguration;
@@ -250,6 +251,11 @@ public class WhisperServerConfiguration extends Configuration {
   @JsonProperty
   private TorExitNodeConfiguration tor;
 
+  @Valid
+  @NotNull
+  @JsonProperty
+  private DonationConfiguration donation;
+
   private Map<String, String> transparentDataIndex = new HashMap<>();
 
   public RecaptchaConfiguration getRecaptchaConfiguration() {
@@ -429,4 +435,8 @@ public class WhisperServerConfiguration extends Configuration {
   public TorExitNodeConfiguration getTorExitNodeConfiguration() {
     return tor;
   }
+
+  public DonationConfiguration getDonationConfiguration() {
+    return donation;
+  }
 }

service/src/main/java/org/whispersystems/textsecuregcm/configuration/DonationConfiguration.java

@@ -0,0 +1,79 @@
+/*
+ * Copyright 2021 Signal Messenger, LLC
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
+package org.whispersystems.textsecuregcm.configuration;
+
+import com.fasterxml.jackson.annotation.JsonProperty;
+import com.google.common.annotations.VisibleForTesting;
+import java.util.Set;
+import javax.validation.Valid;
+import javax.validation.constraints.NotEmpty;
+import javax.validation.constraints.NotNull;
+
+public class DonationConfiguration {
+
+  private String uri;
+  private String apiKey;
+  private Set<String> supportedCurrencies;
+  private CircuitBreakerConfiguration circuitBreaker;
+  private RetryConfiguration retry;
+
+  @JsonProperty
+  @NotEmpty
+  public String getUri() {
+    return uri;
+  }
+
+  @VisibleForTesting
+  public void setUri(final String uri) {
+    this.uri = uri;
+  }
+
+  @JsonProperty
+  @NotEmpty
+  public String getApiKey() {
+    return apiKey;
+  }
+
+  @VisibleForTesting
+  public void setApiKey(final String apiKey) {
+    this.apiKey = apiKey;
+  }
+
+  @JsonProperty
+  @NotEmpty
+  public Set<String> getSupportedCurrencies() {
+    return supportedCurrencies;
+  }
+
+  @VisibleForTesting
+  public void setSupportedCurrencies(final Set<String> supportedCurrencies) {
+    this.supportedCurrencies = supportedCurrencies;
+  }
+
+  @JsonProperty
+  @NotNull
+  @Valid
+  public CircuitBreakerConfiguration getCircuitBreaker() {
+    return circuitBreaker;
+  }
+
+  @VisibleForTesting
+  public void setCircuitBreaker(final CircuitBreakerConfiguration circuitBreaker) {
+    this.circuitBreaker = circuitBreaker;
+  }
+
+  @JsonProperty
+  @NotNull
+  @Valid
+  public RetryConfiguration getRetry() {
+    return retry;
+  }
+
+  @VisibleForTesting
+  public void setRetry(final RetryConfiguration retry) {
+    this.retry = retry;
+  }
+}

service/src/main/java/org/whispersystems/textsecuregcm/controllers/DonationController.java

@@ -0,0 +1,117 @@
+/*
+ * Copyright 2021 Signal Messenger, LLC
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
+package org.whispersystems.textsecuregcm.controllers;
+
+import com.codahale.metrics.annotation.Timed;
+import com.fasterxml.jackson.core.JsonProcessingException;
+import com.fasterxml.jackson.databind.JsonNode;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import io.dropwizard.auth.Auth;
+import io.dropwizard.util.Strings;
+import java.net.URI;
+import java.net.http.HttpClient.Redirect;
+import java.net.http.HttpClient.Version;
+import java.net.http.HttpRequest;
+import java.net.http.HttpResponse;
+import java.net.http.HttpResponse.BodyHandlers;
+import java.nio.charset.StandardCharsets;
+import java.time.Duration;
+import java.util.Base64;
+import java.util.Map;
+import java.util.Set;
+import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.Executor;
+import javax.validation.Valid;
+import javax.ws.rs.Consumes;
+import javax.ws.rs.POST;
+import javax.ws.rs.Path;
+import javax.ws.rs.Produces;
+import javax.ws.rs.core.MediaType;
+import javax.ws.rs.core.Response;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.whispersystems.textsecuregcm.configuration.DonationConfiguration;
+import org.whispersystems.textsecuregcm.entities.ApplePayAuthorizationRequest;
+import org.whispersystems.textsecuregcm.entities.ApplePayAuthorizationResponse;
+import org.whispersystems.textsecuregcm.http.FaultTolerantHttpClient;
+import org.whispersystems.textsecuregcm.http.FormDataBodyPublisher;
+import org.whispersystems.textsecuregcm.storage.Account;
+import org.whispersystems.textsecuregcm.util.SystemMapper;
+
+@Path("/v1/donation")
+public class DonationController {
+
+  private final Logger logger = LoggerFactory.getLogger(DonationController.class);
+
+  private final URI uri;
+  private final String apiKey;
+  private final Set<String> supportedCurrencies;
+  private final FaultTolerantHttpClient httpClient;
+
+  public DonationController(final Executor executor, final DonationConfiguration configuration) {
+    this.uri = URI.create(configuration.getUri());
+    this.apiKey = configuration.getApiKey();
+    this.supportedCurrencies = configuration.getSupportedCurrencies();
+    this.httpClient = FaultTolerantHttpClient.newBuilder()
+        .withCircuitBreaker(configuration.getCircuitBreaker())
+        .withRetry(configuration.getRetry())
+        .withVersion(Version.HTTP_2)
+        .withConnectTimeout(Duration.ofSeconds(10))
+        .withRedirect(Redirect.NEVER)
+        .withExecutor(executor)
+        .withName("donation")
+        .withSecurityProtocol(FaultTolerantHttpClient.SECURITY_PROTOCOL_TLS_1_3)
+        .build();
+  }
+
+  @Timed
+  @POST
+  @Path("/authorize-apple-pay")
+  @Consumes(MediaType.APPLICATION_JSON)
+  @Produces(MediaType.APPLICATION_JSON)
+  public CompletableFuture<Response> getApplePayAuthorization(@Auth Account account, @Valid ApplePayAuthorizationRequest request) {
+    if (!supportedCurrencies.contains(request.getCurrency())) {
+      return CompletableFuture.completedFuture(Response.status(422).build());
+    }
+
+    final HttpRequest httpRequest = HttpRequest.newBuilder()
+        .uri(uri)
+        .POST(FormDataBodyPublisher.of(Map.of(
+            "amount", Long.toString(request.getAmount()),
+            "currency", request.getCurrency())))
+        .header("Authorization", "Basic " + Base64.getEncoder().encodeToString(
+            (apiKey + ":").getBytes(StandardCharsets.UTF_8)))
+        .header("Content-Type", "application/x-www-form-urlencoded")
+        .build();
+    return httpClient.sendAsync(httpRequest, BodyHandlers.ofString())
+        .thenApply(this::processApplePayAuthorizationRemoteResponse);
+  }
+
+  private Response processApplePayAuthorizationRemoteResponse(HttpResponse<String> response) {
+    ObjectMapper mapper = SystemMapper.getMapper();
+
+    if (response.statusCode() >= 200 && response.statusCode() < 300 &&
+        MediaType.APPLICATION_JSON.equalsIgnoreCase(response.headers().firstValue("Content-Type").orElse(null))) {
+      try {
+        final JsonNode jsonResponse = mapper.readTree(response.body());
+        final String id = jsonResponse.get("id").asText(null);
+        final String clientSecret = jsonResponse.get("client_secret").asText(null);
+        if (Strings.isNullOrEmpty(id) || Strings.isNullOrEmpty(clientSecret)) {
+          logger.warn("missing fields in json response in donation controller");
+          return Response.status(500).build();
+        }
+        final String responseJson = mapper.writeValueAsString(new ApplePayAuthorizationResponse(id, clientSecret));
+        return Response.ok(responseJson, MediaType.APPLICATION_JSON_TYPE).build();
+      } catch (JsonProcessingException e) {
+        logger.warn("json processing error in donation controller", e);
+        return Response.status(500).build();
+      }
+    } else {
+      logger.warn("unexpected response code returned to donation controller");
+      return Response.status(500).build();
+    }
+  }
+}

service/src/main/java/org/whispersystems/textsecuregcm/entities/ApplePayAuthorizationRequest.java

@@ -0,0 +1,42 @@
+/*
+ * Copyright 2021 Signal Messenger, LLC
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
+package org.whispersystems.textsecuregcm.entities;
+
+import com.fasterxml.jackson.annotation.JsonProperty;
+import com.google.common.annotations.VisibleForTesting;
+import javax.validation.constraints.Min;
+import javax.validation.constraints.NotEmpty;
+import javax.validation.constraints.Pattern;
+import javax.validation.constraints.Size;
+
+public class ApplePayAuthorizationRequest {
+
+  private String currency;
+  private long amount;
+
+  @JsonProperty
+  @NotEmpty
+  @Size(min=3, max=3)
+  @Pattern(regexp="[a-z]{3}")
+  public String getCurrency() {
+    return currency;
+  }
+
+  public void setCurrency(final String currency) {
+    this.currency = currency;
+  }
+
+  @JsonProperty
+  @Min(0)
+  public long getAmount() {
+    return amount;
+  }
+
+  @VisibleForTesting
+  public void setAmount(final long amount) {
+    this.amount = amount;
+  }
+}

service/src/main/java/org/whispersystems/textsecuregcm/entities/ApplePayAuthorizationResponse.java

@@ -0,0 +1,44 @@
+/*
+ * Copyright 2021 Signal Messenger, LLC
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
+package org.whispersystems.textsecuregcm.entities;
+
+import com.fasterxml.jackson.annotation.JsonCreator;
+import com.fasterxml.jackson.annotation.JsonProperty;
+import io.dropwizard.util.Strings;
+import javax.validation.constraints.NotEmpty;
+
+public class ApplePayAuthorizationResponse {
+
+  private final String id;
+  private final String clientSecret;
+
+  @JsonCreator
+  public ApplePayAuthorizationResponse(
+      @JsonProperty("id") final String id,
+      @JsonProperty("client_secret") final String clientSecret) {
+    if (Strings.isNullOrEmpty(id)) {
+      throw new IllegalArgumentException("id cannot be empty");
+    }
+    if (Strings.isNullOrEmpty(clientSecret)) {
+      throw new IllegalArgumentException("clientSecret cannot be empty");
+    }
+
+    this.id = id;
+    this.clientSecret = clientSecret;
+  }
+
+  @JsonProperty("id")
+  @NotEmpty
+  public String getId() {
+    return id;
+  }
+
+  @JsonProperty("client_secret")
+  @NotEmpty
+  public String getClientSecret() {
+    return clientSecret;
+  }
+}