feat(ses_email): add email services to hyperswitch

config/config.example.toml

@@ -322,9 +322,17 @@ region = "" # The AWS region used by the KMS SDK for decrypting data.
 
 # EmailClient configuration. Only applicable when the `email` feature flag is enabled.
 [email]
-from_email = "[email protected]" # Sender email
-aws_region = ""                   # AWS region used by AWS SES
-base_url = ""                     # Base url used when adding links that should redirect to self
+sender_email = "[email protected]" # Sender email
+aws_region = ""                      # AWS region used by AWS SES
+base_url = ""                        # Base url used when adding links that should redirect to self
+allowed_unverified_days = 1          # Number of days the api calls ( with jwt token ) can be made without verifying the email
+active_email_client = "SES"          # The currently active email client
+
+# Configuration for aws ses, applicable when the active email client is SES
+[email.aws_ses]
+email_role_arn = ""        # The amazon resource name ( arn ) of the role which has permission to send emails
+sts_role_session_name = "" # An identifier for the assumed role session, used to uniquely identify a session.
+
 
 #tokenization configuration which describe token lifetime and payment method for specific connector
 [tokenization]
@@ -427,9 +435,6 @@ credit = { currency = "USD" }
 debit = { currency = "USD" }
 ach = { currency = "USD" }
 
-[pm_filters.stripe]
-cashapp = { country = "US", currency = "USD" }
-
 [pm_filters.prophetpay]
 card_redirect = { currency = "USD" }
 

config/development.toml

@@ -212,9 +212,15 @@ disabled = false
 consumer_group = "SCHEDULER_GROUP"
 
 [email]
-from_email = "notify@example.com"
+sender_email = "example@example.com"
 aws_region = ""
-base_url = ""
+base_url = "http://localhost:8080"
+allowed_unverified_days = 1
+active_email_client = "SES"
+
+[email.aws_ses]
+email_role_arn = ""
+sts_role_session_name = ""
 
 [bank_config.eps]
 stripe = { banks = "arzte_und_apotheker_bank,austrian_anadi_bank_ag,bank_austria,bankhaus_carl_spangler,bankhaus_schelhammer_und_schattera_ag,bawag_psk_ag,bks_bank_ag,brull_kallmus_bank_ag,btv_vier_lander_bank,capital_bank_grawe_gruppe_ag,dolomitenbank,easybank_ag,erste_bank_und_sparkassen,hypo_alpeadriabank_international_ag,hypo_noe_lb_fur_niederosterreich_u_wien,hypo_oberosterreich_salzburg_steiermark,hypo_tirol_bank_ag,hypo_vorarlberg_bank_ag,hypo_bank_burgenland_aktiengesellschaft,marchfelder_bank,oberbank_ag,raiffeisen_bankengruppe_osterreich,schoellerbank_ag,sparda_bank_wien,volksbank_gruppe,volkskreditbank_ag,vr_bank_braunau" }

crates/external_services/Cargo.toml

@@ -16,6 +16,7 @@ async-trait = "0.1.68"
 aws-config = { version = "0.55.3", optional = true }
 aws-sdk-kms = { version = "0.28.0", optional = true }
 aws-sdk-sesv2 = "0.28.0"
+aws-sdk-sts = "0.28.0"
 aws-smithy-client = "0.55.3"
 base64 = "0.21.2"
 dyn-clone = "1.0.11"
@@ -24,6 +25,8 @@ once_cell = "1.18.0"
 serde = { version = "1.0.163", features = ["derive"] }
 thiserror = "1.0.40"
 tokio = "1.28.2"
+hyper-proxy = "0.9.1"
+hyper = "0.14.26"
 
 # First party crates
 common_utils = { version = "0.1.0", path = "../common_utils" }

crates/external_services/src/email.rs

@@ -1,127 +1,163 @@
 //! Interactions with the AWS SES SDK
 
-use aws_config::meta::region::RegionProviderChain;
-use aws_sdk_sesv2::{
-    config::Region,
-    operation::send_email::SendEmailError,
-    types::{Body, Content, Destination, EmailContent, Message},
-    Client,
-};
+use aws_sdk_sesv2::types::Body;
 use common_utils::{errors::CustomResult, pii};
-use error_stack::{IntoReport, ResultExt};
-use masking::PeekInterface;
 use serde::Deserialize;
 
+/// Implementation of aws ses client
+pub mod ses;
+
 /// Custom Result type alias for Email operations.
 pub type EmailResult<T> = CustomResult<T, EmailError>;
 
 /// A trait that defines the methods that must be implemented to send email.
 #[async_trait::async_trait]
 pub trait EmailClient: Sync + Send + dyn_clone::DynClone {
+    /// The rich text type of the email client
+    type RichText;
+
     /// Sends an email to the specified recipient with the given subject and body.
     async fn send_email(
         &self,
         recipient: pii::Email,
         subject: String,
-        body: String,
+        body: Self::RichText,
+        proxy_url: Option<&String>,
+    ) -> EmailResult<()>;
+
+    /// Convert Stringified HTML to client native rich text format
+    /// This has to be done because not all clients may format html as the same
+    fn convert_to_rich_text(
+        &self,
+        intermediate_string: IntermediateString,
+    ) -> CustomResult<Self::RichText, EmailError>
+    where
+        Self::RichText: Send;
+}
+
+/// A super trait which is automatically implemented for all EmailClients
+#[async_trait::async_trait]
+pub trait EmailService: Sync + Send + dyn_clone::DynClone {
+    /// Compose and send email using the email data
+    async fn compose_and_send_email(
+        &self,
+        email_data: Box<dyn EmailData + Send>,
+        proxy_url: Option<&String>,
     ) -> EmailResult<()>;
 }
 
-dyn_clone::clone_trait_object!(EmailClient);
+#[async_trait::async_trait]
+impl<T> EmailService for T
+where
+    T: EmailClient,
+    <Self as EmailClient>::RichText: Send,
+{
+    async fn compose_and_send_email(
+        &self,
+        email_data: Box<dyn EmailData + Send>,
+        proxy_url: Option<&String>,
+    ) -> EmailResult<()> {
+        let email_data = email_data.get_email_data();
+        let email_data = email_data.await?;
+
+        let EmailContents {
+            subject,
+            body,
+            recipient,
+        } = email_data;
+
+        let rich_text_string = self.convert_to_rich_text(body)?;
+
+        self.send_email(recipient, subject, rich_text_string, proxy_url)
+            .await
+    }
+}
+
+/// This is a struct used to create Intermediate String for rich text ( html )
+#[derive(Debug)]
+pub struct IntermediateString(String);
+
+impl IntermediateString {
+    /// Create a new Instance of IntermediateString using a string
+    pub fn new(inner: String) -> Self {
+        Self(inner)
+    }
+
+    /// Get the inner String
+    pub fn into_inner(self) -> String {
+        self.0
+    }
+}
+
+/// Temporary output for the email subject
+#[derive(Debug)]
+pub struct EmailContents {
+    /// The subject of email
+    pub subject: String,
+
+    /// This will be the intermediate representation of the the email body in a generic format.
+    /// The email clients can convert this intermediate representation to their client specific rich text format
+    pub body: IntermediateString,
+
+    /// The email of the recipient to whom the email has to be sent
+    pub recipient: pii::Email,
+}
+
+/// A trait which will contain the logic of generating the email subject and body
+#[async_trait::async_trait]
+pub trait EmailData {
+    /// Get the email contents
+    async fn get_email_data(&self) -> CustomResult<EmailContents, EmailError>;
+}
+
+dyn_clone::clone_trait_object!(EmailClient<RichText = Body>);
+
+/// List of available email clients to choose from
+#[derive(Debug, Clone, Default, Deserialize)]
+pub enum AvailableEmailClients {
+    #[default]
+    /// AWS ses email client
+    SES,
+}
 
 /// Struct that contains the settings required to construct an EmailClient.
 #[derive(Debug, Clone, Default, Deserialize)]
 pub struct EmailSettings {
-    /// Sender email.
-    pub from_email: String,
-
     /// The AWS region to send SES requests to.
     pub aws_region: String,
 
     /// Base-url used when adding links that should redirect to self
     pub base_url: String,
-}
 
-/// Client for AWS SES operation
-#[derive(Debug, Clone)]
-pub struct AwsSes {
-    ses_client: Client,
-    from_email: String,
-}
+    /// Number of days for verification of the email
+    pub allowed_unverified_days: i64,
 
-impl AwsSes {
-    /// Constructs a new AwsSes client
-    pub async fn new(conf: &EmailSettings) -> Self {
-        let region_provider = RegionProviderChain::first_try(Region::new(conf.aws_region.clone()));
-        let sdk_config = aws_config::from_env().region(region_provider).load().await;
+    /// Sender email
+    pub sender_email: String,
 
-        Self {
-            ses_client: Client::new(&sdk_config),
-            from_email: conf.from_email.clone(),
-        }
-    }
-}
+    /// Configs related to AWS Simple Email Service
+    pub aws_ses: Option<ses::SESConfig>,
 
-#[async_trait::async_trait]
-impl EmailClient for AwsSes {
-    async fn send_email(
-        &self,
-        recipient: pii::Email,
-        subject: String,
-        body: String,
-    ) -> EmailResult<()> {
-        self.ses_client
-            .send_email()
-            .from_email_address(self.from_email.to_owned())
-            .destination(
-                Destination::builder()
-                    .to_addresses(recipient.peek())
-                    .build(),
-            )
-            .content(
-                EmailContent::builder()
-                    .simple(
-                        Message::builder()
-                            .subject(Content::builder().data(subject).build())
-                            .body(
-                                Body::builder()
-                                    .text(Content::builder().data(body).charset("UTF-8").build())
-                                    .build(),
-                            )
-                            .build(),
-                    )
-                    .build(),
-            )
-            .send()
-            .await
-            .map_err(AwsSesError::SendingFailure)
-            .into_report()
-            .change_context(EmailError::EmailSendingFailure)?;
-
-        Ok(())
-    }
+    /// The active email client to use
+    pub active_email_client: AvailableEmailClients,
 }
 
-#[allow(missing_docs)]
 /// Errors that could occur from EmailClient.
 #[derive(Debug, thiserror::Error)]
 pub enum EmailError {
     /// An error occurred when building email client.
     #[error("Error building email client")]
     ClientBuildingFailure,
+
     /// An error occurred when sending email
     #[error("Error sending email to recipient")]
     EmailSendingFailure,
+
+    /// Failed to generate the email token
     #[error("Failed to generate email token")]
     TokenGenerationFailure,
+
+    /// The expected feature is not implemented
     #[error("Feature not implemented")]
     NotImplemented,
 }
-
-/// Errors that could occur during SES operations.
-#[derive(Debug, thiserror::Error)]
-pub enum AwsSesError {
-    /// An error occurred in the SDK while sending email.
-    #[error("Failed to Send Email {0:?}")]
-    SendingFailure(aws_smithy_client::SdkError<SendEmailError>),
-}