[SDK-2622] Add expiresAt to token response

src/main/java/com/auth0/json/auth/TokenHolder.java

@@ -1,36 +1,43 @@
 package com.auth0.json.auth;
 
-import com.fasterxml.jackson.annotation.JsonIgnoreProperties;
-import com.fasterxml.jackson.annotation.JsonInclude;
-import com.fasterxml.jackson.annotation.JsonProperty;
+import com.fasterxml.jackson.databind.annotation.JsonDeserialize;
+
+import java.util.Date;
 
 /**
  * Class that contains the Tokens obtained after a call to the {@link com.auth0.client.auth.AuthAPI} methods.
  */
 @SuppressWarnings("unused")
-@JsonIgnoreProperties(ignoreUnknown = true)
-@JsonInclude(JsonInclude.Include.NON_NULL)
+@JsonDeserialize(using = TokenHolderDeserializer.class)
 public class TokenHolder {
 
-    @JsonProperty("access_token")
     private String accessToken;
-    @JsonProperty("id_token")
     private String idToken;
-    @JsonProperty("refresh_token")
     private String refreshToken;
-    @JsonProperty("token_type")
     private String tokenType;
-    @JsonProperty("expires_in")
     private long expiresIn;
-    @JsonProperty("scope")
     private String scope;
+    private Date expiresAt;
+
+    // We need to maintain a default constructor for backwards-compatibility
+    @SuppressWarnings("unused")
+    public TokenHolder() {}
+
+    public TokenHolder(String accessToken, String idToken, String refreshToken, String tokenType, long expiresIn, String scope, Date expiresAt) {
+        this.accessToken = accessToken;
+        this.idToken = idToken;
+        this.refreshToken = refreshToken;
+        this.tokenType = tokenType;
+        this.expiresIn = expiresIn;
+        this.scope = scope;
+        this.expiresAt = expiresAt;
+    }
 
     /**
      * Getter for the Auth0's access token.
      *
      * @return the access token or null if missing.
      */
-    @JsonProperty("access_token")
     public String getAccessToken() {
         return accessToken;
     }
@@ -40,7 +47,6 @@ public String getAccessToken() {
      *
      * @return the id token or null if missing.
      */
-    @JsonProperty("id_token")
     public String getIdToken() {
         return idToken;
     }
@@ -50,7 +56,6 @@ public String getIdToken() {
      *
      * @return the refresh token or null if missing.
      */
-    @JsonProperty("refresh_token")
     public String getRefreshToken() {
         return refreshToken;
     }
@@ -60,28 +65,37 @@ public String getRefreshToken() {
      *
      * @return the token type or null if missing.
      */
-    @JsonProperty("token_type")
     public String getTokenType() {
         return tokenType;
     }
 
     /**
-     * Getter for the duration of this token in seconds since it was issued.
+     * Getter for the duration of the Access Token token in seconds from the time it was issued. If no Access Token was
+     * present the value will be zero.
      *
-     * @return the number of seconds in which this token will expire, since the time it was issued.
+     * @return the number of seconds in which the Access Token token will expire, from the time it was issued.
      */
-    @JsonProperty("expires_in")
     public long getExpiresIn() {
         return expiresIn;
     }
 
+    /**
+     * Get the expiration date of the Access Token. This value is <strong>not</strong> part of the actual token response from the
+     * API, but rather is calculated and provided for convenience.
+     *
+     * @return the date of the Access Token's expiration. If no Access Token was present on the response, returns {@code null}
+     */
+    public Date getExpiresAt() {
+        return expiresAt;
+    }
+
     /**
      * Gets the granted scope value for this token.
      *
      * @return a space-delimited string of the granted scopes of this token.
      */
-    @JsonProperty
     public String getScope() {
         return scope;
     }
+
 }

src/main/java/com/auth0/json/auth/TokenHolderDeserializer.java

@@ -0,0 +1,51 @@
+package com.auth0.json.auth;
+
+import com.fasterxml.jackson.core.JsonParser;
+import com.fasterxml.jackson.core.JsonProcessingException;
+import com.fasterxml.jackson.databind.DeserializationContext;
+import com.fasterxml.jackson.databind.JsonNode;
+import com.fasterxml.jackson.databind.deser.std.StdDeserializer;
+
+import java.io.IOException;
+import java.time.Instant;
+import java.util.Date;
+
+/**
+ * A custom Jackson Deserializer for the {@linkplain TokenHolder} object. It deserializes the JSON response and calculates
+ * an {@code expiresAt} date derived from the current time and the {@code expires_at} returned on the response.
+ */
+public class TokenHolderDeserializer extends StdDeserializer<TokenHolder> {
+
+    @SuppressWarnings("unused")
+    public TokenHolderDeserializer() {
+        this(null);
+    }
+
+    public TokenHolderDeserializer(Class<?> clazz) {
+        super(clazz);
+    }
+
+    @Override
+    public TokenHolder deserialize(JsonParser p, DeserializationContext ctxt) throws IOException, JsonProcessingException {
+        JsonNode node = p.getCodec().readTree(p);
+
+        JsonNode accessTokenNode = node.get("access_token");
+        JsonNode idTokenNode = node.get("id_token");
+        JsonNode refreshTokenNode = node.get("refresh_token");
+        JsonNode tokenTypeNode = node.get("token_type");
+        JsonNode scopeNode = node.get("scope");
+        JsonNode expiresInNode = node.get("expires_in");
+
+        String accessToken = accessTokenNode != null ? accessTokenNode.asText() : null;
+        String idToken = idTokenNode !=  null ? idTokenNode.asText() : null;
+        String refreshToken = refreshTokenNode != null ? refreshTokenNode.asText() : null;
+        String tokenType = tokenTypeNode != null  ? tokenTypeNode.asText() : null;
+        String scope = scopeNode != null ?  scopeNode.asText() : null;
+
+        // As a primitive, if expires_in is not sent on the response, value will be 0 instead of null
+        long expiresIn = expiresInNode !=  null ? expiresInNode.asLong() : 0L;
+        Date expiresAt = expiresInNode != null ? Date.from(Instant.now().plusSeconds(expiresIn)) : null;
+
+        return new TokenHolder(accessToken, idToken, refreshToken, tokenType, expiresIn, scope, expiresAt);
+    }
+}

src/test/java/com/auth0/json/auth/TokenHolderTest.java

@@ -3,25 +3,81 @@
 import com.auth0.json.JsonTest;
 import org.junit.Test;
 
+import java.time.Instant;
+import java.util.Date;
+
 import static org.hamcrest.MatcherAssert.assertThat;
-import static org.hamcrest.Matchers.is;
-import static org.hamcrest.Matchers.notNullValue;
+import static org.hamcrest.Matchers.*;
 
 public class TokenHolderTest extends JsonTest<TokenHolder> {
 
-    private static final String json = "{\"id_token\":\"eyJ0eXAiOiJKV1Qi...\",\"access_token\":\"A9CvPwFojaBI...\",\"refresh_token\":\"GEbRxBN...edjnXbL\",\"token_type\": \"bearer\",\"expires_in\":86000, \"scope\": \"openid profile email\"}";
-
     @Test
     public void shouldDeserialize() throws Exception {
+        String json = "{\"id_token\":\"eyJ0eXAiOiJKV1Qi...\",\"access_token\":\"A9CvPwFojaBI...\",\"refresh_token\":\"GEbRxBN...edjnXbL\",\"token_type\": \"bearer\",\"expires_in\":86000, \"scope\": \"openid profile email\"}";
+
+        TokenHolder holder = fromJSON(json, TokenHolder.class);
+
+        assertThat(holder, is(notNullValue()));
+        assertThat(holder.getAccessToken(), is("A9CvPwFojaBI..."));
+        assertThat(holder.getIdToken(), is("eyJ0eXAiOiJKV1Qi..."));
+        assertThat(holder.getRefreshToken(), is("GEbRxBN...edjnXbL"));
+        assertThat(holder.getTokenType(), is("bearer"));
+        assertThat(holder.getExpiresIn(), is(86000L));
+        assertThat(holder.getScope(), is("openid profile email"));
+
+        // allow for a small tolerance since now may be calculated at slightly different times in the test
+        assertThat(getExpectedExpiredAtDiff(86000, holder.getExpiresAt()), is(lessThanOrEqualTo(2L)));
+
+    }
+
+    @Test
+    public void shouldDeserializeWithUnexpectedValues() throws Exception {
+        String json = "{\"id_token\":\"eyJ0eXAiOiJKV1Qi...\",\"access_token\":\"A9CvPwFojaBI...\",\"refresh_token\":\"GEbRxBN...edjnXbL\",\"token_type\": \"bearer\",\"expires_in\":86000, \"scope\": \"openid profile email\", \"some-key\": \"some-value\"}";
+
+        TokenHolder holder = fromJSON(json, TokenHolder.class);
+
+        assertThat(holder, is(notNullValue()));
+        assertThat(holder.getAccessToken(), is("A9CvPwFojaBI..."));
+        assertThat(holder.getIdToken(), is("eyJ0eXAiOiJKV1Qi..."));
+        assertThat(holder.getRefreshToken(), is("GEbRxBN...edjnXbL"));
+        assertThat(holder.getTokenType(), is("bearer"));
+        assertThat(holder.getExpiresIn(), is(86000L));
+        assertThat(holder.getScope(), is("openid profile email"));
+
+        // allow for a small tolerance since now may be calculated at slightly different times in the test
+        assertThat(getExpectedExpiredAtDiff(86000, holder.getExpiresAt()), is(lessThanOrEqualTo(2L)));
+    }
+
+    @Test
+    public void shouldDeserializeWithMissingFields() throws Exception {
+        String json = "{}";
+
         TokenHolder holder = fromJSON(json, TokenHolder.class);
 
         assertThat(holder, is(notNullValue()));
+        assertThat(holder.getAccessToken(), is(nullValue()));
+        assertThat(holder.getIdToken(), is(nullValue()));
+        assertThat(holder.getRefreshToken(), is(nullValue()));
+        assertThat(holder.getTokenType(), is(nullValue()));
+        assertThat(holder.getScope(), is(nullValue()));
+
+        // as a primitive, a missing value in the JSON will result in a value of zero on the value object.
+        assertThat(holder.getExpiresIn(), is(0L));
+        assertThat(holder.getExpiresAt(), is(nullValue()));
+
+    }
+
+    @Test
+    public void shouldHaveDefaultConstructor() {
+        // To ensure default constructor exists for backwards-compatibility
+        TokenHolder tokenHolder = new TokenHolder();
+        assertThat(tokenHolder, is(notNullValue()));
+    }
 
-        assertThat(holder.getAccessToken(), is(notNullValue()));
-        assertThat(holder.getIdToken(), is(notNullValue()));
-        assertThat(holder.getRefreshToken(), is(notNullValue()));
-        assertThat(holder.getTokenType(), is(notNullValue()));
-        assertThat(holder.getExpiresIn(), is(notNullValue()));
-        assertThat(holder.getScope(), is(notNullValue()));
+    private long getExpectedExpiredAtDiff(long expiresIn, Date expiresAt) {
+        Instant expectedExpiresAt  = Instant.now().plusSeconds(expiresIn);
+        long expectedEpochSeconds = expectedExpiresAt.getEpochSecond();
+        long actualEpochSeconds = expiresAt.toInstant().getEpochSecond();
+        return Math.abs(expectedEpochSeconds - actualEpochSeconds);
     }
-}
+}