Allow importing GPG key as a base64 string (#14)

README.md

@@ -36,13 +36,23 @@ ___
 
 ## Prerequisites
 
-First, export the GPG private key as an ASCII armored version:
+First, export the GPG private key as an ASCII armored version to your clipboard:
 
 ```shell
-gpg --armor --export-secret-key --output key.pgp joe@foo.bar
+# macOS
+gpg --armor --export-secret-key joe@foo.bar | pbcopy
+
+# Ubuntu (assuming GNU base64)
+gpg --armor --export-secret-key joe@foo.bar -w0 | xclip
+
+# Arch
+gpg --armor --export-secret-key joe@foo.bar | sed -z 's;\n;;g' | xclip -selection clipboard -i
+
+# FreeBSD (assuming BSD base64)
+gpg --armor --export-secret-key joe@foo.bar | xclip
 ```
 
-Copy the content of `key.pgp` file as a [`secret`](https://help.github.com/en/actions/configuring-and-managing-workflows/creating-and-storing-encrypted-secrets) named `GPG_PRIVATE_KEY` for example. Create another secret with the `PASSPHRASE` if applicable.
+Paste your clipboard as a [`secret`](https://help.github.com/en/actions/configuring-and-managing-workflows/creating-and-storing-encrypted-secrets) named `GPG_PRIVATE_KEY` for example. Create another secret with the `PASSPHRASE` if applicable.
 
 ## Usage
 
@@ -141,11 +151,11 @@ Following outputs are available
 
 ### environment variables
 
-Following environment variables can be used as `step.env` keys
+Following environment variables must be used as `step.env` keys
 
 | Name               | Description                           |
 |--------------------|---------------------------------------|
-| `GPG_PRIVATE_KEY`  | GPG private key exported as an ASCII armored version (**required**) |
+| `GPG_PRIVATE_KEY`  | GPG private key exported as an ASCII armored version or its base64 encoding (**required**) |
 | `PASSPHRASE`       | Passphrase of the `GPG_PRIVATE_KEY` key if setted |
 
 ## How can I help?

__tests__/openpgp.test.ts

@@ -19,7 +19,7 @@ const userInfo = {
 
 describe('openpgp', () => {
   describe('readPrivateKey', () => {
-    it('returns a PGP private key', async () => {
+    it('returns a PGP private key from an armored string', async () => {
       await openpgp.readPrivateKey(userInfo.pgp).then(privateKey => {
         expect(privateKey.keyID).toEqual(userInfo.keyID);
         expect(privateKey.name).toEqual(userInfo.name);
@@ -27,6 +27,14 @@ describe('openpgp', () => {
         expect(privateKey.fingerprint).toEqual(userInfo.fingerprint);
       });
     });
+    it('returns a PGP private key from a base64 armored string', async () => {
+      await openpgp.readPrivateKey(Buffer.from(userInfo.pgp).toString('base64')).then(privateKey => {
+        expect(privateKey.keyID).toEqual(userInfo.keyID);
+        expect(privateKey.name).toEqual(userInfo.name);
+        expect(privateKey.email).toEqual(userInfo.email);
+        expect(privateKey.fingerprint).toEqual(userInfo.fingerprint);
+      });
+    });
   });
 
   describe('generateKeyPair', () => {

src/openpgp.ts

@@ -18,7 +18,8 @@ export const readPrivateKey = async (armoredText: string): Promise<PrivateKey> =
   const {
     keys: [privateKey],
     err: err
-  } = await openpgp.key.readArmored(armoredText);
+  } = await openpgp.key.readArmored(isArmored(armoredText) ? armoredText : Buffer.from(armoredText, 'base64').toString());
+
   if (err?.length) {
     throw err[0];
   }
@@ -51,3 +52,5 @@ export const generateKeyPair = async (name: string, email: string, passphrase: s
     privateKey: keyPair.privateKeyArmored.replace(/\r\n/g, '\n').trim()
   };
 };
+
+const isArmored = (text: string) => text.trimLeft().startsWith('---');