Only demand that SMTP is configured when it is actually needed

The future of GitGitGadget is that it comes in the form of a set of
GitHub Actions; Most won't send emails and therefore do not need the
SMTP configuration, so let's not require it in those instances.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>

Author: dscho

lib/gitgitgadget.ts

@@ -71,10 +71,15 @@ export class GitGitGadget {
             const smtpPass = await getVar("smtpPass", gitGitGadgetDir);
             const smtpOpts = await getVar("smtpOpts", gitGitGadgetDir);
 
-            if (!smtpUser || !smtpHost || !smtpPass) {
-                throw new Error("No SMTP settings configured");
+            if (smtpUser && smtpHost && smtpPass) smtpOptions = { smtpHost, smtpOpts, smtpPass, smtpUser };
+            else if (smtpUser || smtpHost || smtpPass) {
+                const missing: string[] = [
+                    smtpUser ? "" : "smtpUser",
+                    smtpHost ? "" : "smtpHost",
+                    smtpPass ? "" : "smtpPass",
+                ].filter((e) => e);
+                throw new Error(`Partial SMTP configuration detected (${missing.join(", ")} missing)`);
             }
-            smtpOptions = { smtpHost, smtpOpts, smtpPass, smtpUser };
         }
 
         const [options, allowedUsers] = await GitGitGadget.readOptions(notes);
@@ -98,7 +103,7 @@ export class GitGitGadget {
     protected options: IGitGitGadgetOptions;
     protected allowedUsers: Set<string>;
 
-    protected readonly smtpOptions: ISMTPOptions;
+    protected readonly smtpOptions?: ISMTPOptions;
 
     protected readonly publishTagsAndNotesToRemote: string;
     private readonly publishToken: string | undefined;
@@ -107,7 +112,7 @@ export class GitGitGadget {
         notes: GitNotes,
         options: IGitGitGadgetOptions,
         allowedUsers: Set<string>,
-        smtpOptions: ISMTPOptions,
+        smtpOptions: ISMTPOptions | undefined,
         publishTagsAndNotesToRemote: string,
         publishToken?: string,
     ) {
@@ -168,6 +173,10 @@ export class GitGitGadget {
 
     // Send emails only to the user
     public async preview(pr: IPullRequestInfo, userInfo: IGitHubUser): Promise<IPatchSeriesMetadata | undefined> {
+        const smtpOptions = this.smtpOptions;
+        if (!smtpOptions) {
+            throw new Error("No SMTP options configured");
+        }
         if (!userInfo.email) {
             throw new Error(`No email in user info for ${userInfo.login}`);
         }
@@ -178,16 +187,20 @@ export class GitGitGadget {
             mbox.cc = [];
             mbox.to = email;
             console.log(mbox);
-            return await sendMail(mbox, this.smtpOptions);
+            return await sendMail(mbox, smtpOptions);
         };
 
         return await this.genAndSend(pr, userInfo, { noUpdate: true }, send);
     }
 
     // Send emails out for review
     public async submit(pr: IPullRequestInfo, userInfo: IGitHubUser): Promise<IPatchSeriesMetadata | undefined> {
+        const smtpOptions = this.smtpOptions;
+        if (!smtpOptions) {
+            throw new Error("No SMTP options configured");
+        }
         const send = async (mail: string): Promise<string> => {
-            return await parseHeadersAndSendMail(mail, this.smtpOptions);
+            return await parseHeadersAndSendMail(mail, smtpOptions);
         };
 
         return await this.genAndSend(pr, userInfo, {}, send);