Added independant opaque return types for all calls.

Author: ed7coyne

Firebase.cpp

@@ -31,6 +31,40 @@ String makeUrl(const String& path, const String& auth) {
   return url;
 }
 
+class FirebaseCall {
+ public:
+  FirebaseCall(const String& host, const String& auth,
+               const char* method, const String& path, const String& value,
+               HTTPClient* http);
+  FirebaseCall(const String& host, const String& auth,
+               const char* method, const String& path,
+               HTTPClient* http);
+
+
+  // True if there was an error completing call.
+  bool isError() const;
+  String errorMessage() const;
+
+  // True if http status code is 200(OK).
+  bool isOk() const;
+
+  // Message sent back from Firebase backend. This pulls value to local memory,
+  // be careful if value can be large.
+  String rawResponse();
+
+  int httpStatus() const {
+    return status_;
+  }
+
+ private:
+  FirebaseCall(HTTPClient* http);
+
+  HTTPClient* http_;
+
+  int status_;
+  String error_message_;
+};
+
 }  // namespace
 
 Firebase::Firebase(const String& host) : host_(host) {
@@ -42,24 +76,36 @@ Firebase& Firebase::auth(const String& auth) {
   return *this;
 }
 
-FirebaseCall Firebase::get(const String& path) {
-  return FirebaseCall(host_, auth_, "GET", path, &http_);
+FirebaseGetResult Firebase::get(const String& path) {
+  FirebaseCall call(host_, auth_, "GET", path, &http_);
+  return call.isError() ? FirebaseGetResult::FromError(call.errorMessage())
+      : FirebaseGetResult::FromResponse(call.rawResponse());
 }
 
-FirebaseCall Firebase::push(const String& path, const String& value) {
-  return FirebaseCall(host_, auth_, "POST", path, value, &http_);
+FirebasePushResult Firebase::push(const String& path, const String& value) {
+  FirebaseCall call(host_, auth_, "POST", path, value, &http_);
+  return call.isError() ? FirebasePushResult::FromError(call.errorMessage())
+      : FirebasePushResult::FromResponse(call.rawResponse());
 }
 
-FirebaseCall Firebase::remove(const String& path) {
-  return FirebaseCall(host_, auth_, "DELETE", path, &http_);
+FirebaseRemoveResult Firebase::remove(const String& path) {
+  FirebaseCall call(host_, auth_, "DELETE", path, &http_);
+  if (call.isError()) {
+    return FirebaseRemoveResult::FromError(call.errorMessage());
+  }
+  // Remove is only complete if returned status is OK(200).
+  if (!call.isOk()) {
+    return FirebaseRemoveResult::FromError(
+        "Remove " + path + " returned with status " + call.httpStatus());
+  }
+  return FirebaseRemoveResult::Ok();
 }
 
 FirebaseEventStream Firebase::stream(const String& path) {
   return FirebaseEventStream(host_, auth_, path);
 }
 
 /* FirebaseCall */
-
 FirebaseCall::FirebaseCall(const String& host, const String& auth,
                            const char* method, const String& path, const String& value,
                            HTTPClient* http) : http_(http) {
@@ -154,4 +200,56 @@ String FirebaseEventStream::errorMessage() const {
   return error_message_;
 }
 
+FirebaseEventStream::operator bool() {
+  return !isError() && connected();
+}
+
+/* FirebaseResult */
+
+FirebaseResult::FirebaseResult(const String& error_message)
+  : is_error_(true), error_message_(error_message) {}
+
+FirebaseResult::FirebaseResult() {}
+
+FirebaseResult::operator bool() const {
+  return !isError();
+}
+
+bool FirebaseResult::isError() const {
+  return is_error_;
+}
+
+const String& FirebaseResult::errorMessage() const {
+  return error_message_;
+}
+
+/* FirebaseRemoveResult */
+
+FirebaseRemoveResult::FirebaseRemoveResult(const String& error_message)
+  : FirebaseResult(error_message) {}
+
+FirebaseRemoveResult::FirebaseRemoveResult() {}
+
+
+/* FirebasePushResult */
+
+FirebasePushResult::FirebasePushResult(const String& error_message)
+  : FirebaseResult(error_message) {}
+
+FirebasePushResult::FirebasePushResult() {}
+
+const String& FirebasePushResult::name() const {
+  return name_;
+}
+
+/* FirebaseGetResult */
+
+FirebaseGetResult::FirebaseGetResult(const String& error_message)
+  : FirebaseResult(error_message) {}
+
+FirebaseGetResult::FirebaseGetResult() {}
+
+const String& FirebaseGetResult::rawResponse() {
+  return response_;
+}
 

Firebase.h

@@ -25,9 +25,9 @@
 #include <WiFiClientSecure.h>
 #include <ESP8266HTTPClient.h>
 
-//TODO(edcoyne) split these into multiple files.
-
-class FirebaseCall;
+class FirebaseGetResult;
+class FirebasePushResult;
+class FirebaseRemoveResult;
 class FirebaseEventStream;
 
 // Primary client to the Firebase backend.
@@ -38,55 +38,103 @@ class Firebase {
 
   // Fetch result at "path" to a local variable. If the value is too large you will exceed
   // local memory.
-  FirebaseCall get(const String& path);
+  FirebaseGetResult get(const String& path);
 
   // Add new value to list at "path", will return child name of new item.
-  FirebaseCall push(const String& path, const String& value);
+  FirebasePushResult push(const String& path, const String& value);
 
   // Deletes value at "path" from server.
-  FirebaseCall remove(const String& path);
+  FirebaseRemoveResult remove(const String& path);
 
   // Starts a stream of events that effect object at "path".
   FirebaseEventStream stream(const String& path);
 
  private:
+
+  int sendRequest(const char* method, const String& path, const String& value);
+
   HTTPClient http_;
   String host_;
   String auth_;
 };
 
-class FirebaseCall {
+
+// Result from a Firebase call.
+class FirebaseResult {
  public:
-  FirebaseCall(const String& host, const String& auth,
-               const char* method, const String& path, const String& value,
-               HTTPClient* http);
-  FirebaseCall(const String& host, const String& auth,
-               const char* method, const String& path,
-               HTTPClient* http);
+  // Constructor for error result.
+  FirebaseResult(const String& error_message);
+  // Constructor if no error.
+  FirebaseResult();
 
+  // True if no error.
+  operator bool() const;
 
-  // True if there was an error completing call.
   bool isError() const;
-  String errorMessage() const;
 
-  // True if http status code is 200(OK).
-  bool isOk() const;
+  const String& errorMessage() const;
+
+ private:
+  bool is_error_ = false;
+  String error_message_;
+};
 
-  // Message sent back from Firebase backend. This pulls value to local memory,
-  // be careful if value can be large.
-  String rawResponse();
+class FirebaseRemoveResult : public FirebaseResult {
+ public:
+  static FirebaseRemoveResult FromError(const String& error_message) {
+    return FirebaseRemoveResult(error_message);
+  }
 
-  int httpStatus() const {
-    return status_;
+  static FirebaseRemoveResult Ok() {
+    return FirebaseRemoveResult();
   }
 
  private:
-  FirebaseCall(HTTPClient* http);
+  FirebaseRemoveResult(const String& error_message);
+  FirebaseRemoveResult();
+};
 
-  HTTPClient* http_;
+class FirebasePushResult : public FirebaseResult {
+ public:
+  static FirebasePushResult FromError(const String& error_message) {
+    return FirebasePushResult(error_message);
+  }
 
-  int status_;
-  String error_message_;
+  static FirebasePushResult FromResponse(const String& response) {
+    FirebasePushResult result;
+    // TODO(edcoyne): add json parsing to get name object.
+    result.name_ = response;
+    return result;
+  }
+
+  const String& name() const;
+
+ private:
+  FirebasePushResult(const String& error_message);
+  FirebasePushResult();
+
+  String name_;
+};
+
+class FirebaseGetResult : public FirebaseResult {
+ public:
+  static FirebaseGetResult FromError(const String& error_message) {
+    return FirebaseGetResult(error_message);
+  }
+
+  static FirebaseGetResult FromResponse(const String& response) {
+    FirebaseGetResult result;
+    result.response_ = response;
+    return result;
+  }
+
+  const String& rawResponse();
+
+ private:
+  FirebaseGetResult(const String& error_message);
+  FirebaseGetResult();
+
+  String response_;
 };
 
 class FirebaseEventStream {
@@ -108,6 +156,9 @@ class FirebaseEventStream {
   // True if there is an event available.
   bool available();
 
+  // True if no error and stream is connected.
+  operator bool();
+
   // True if there was an error.
   bool isError() const;
   String errorMessage() const;

examples/FirebasePush_ESP8266/FirebasePush_ESP8266.ino

@@ -38,20 +38,20 @@ void setup() {
   Serial.println(WiFi.localIP());
 
    // add a new entry.
-  FirebaseCall push = fbase.push("/logs", "{\".sv\": \"timestamp\"}");
-  if (push.isError()) {
+  FirebasePushResult push = fbase.push("/logs", "{\".sv\": \"timestamp\"}");
+  if (!push) {
       Serial.println("Firebase request failed");
       Serial.println(push.errorMessage());  
       return;
   }
 
   // print response.
-  Serial.println(push.rawResponse());
+  Serial.println(push.name());
 
   // print all entries.
-  FirebaseCall fetch = fbase.get("/logs");
-  if (!fetch.isError()) {
-    Serial.println(fetch.rawResponse());
+  FirebaseGetResult get = fbase.get("/logs");
+  if (get) {
+    Serial.println(get.rawResponse());
   }
 }
 

examples/FirebaseStream_ESP8266/FirebaseStream_ESP8266.ino

@@ -47,7 +47,7 @@ void setup() {
 
 void loop() {  
   static FirebaseEventStream stream = fbase.stream("/bitcoin");
-  if (stream.isError()) {
+  if (!stream) {
     Serial.println("streaming error");
     Serial.println(stream.errorMessage());
   }