fix: stringify json object based secrets (#247)

lib/backends/kv-backend.js

@@ -82,6 +82,23 @@ class KVBackend extends AbstractBackend {
     throw new Error('_get not implemented')
   }
 
+  /**
+   * Convert secret value to buffer
+   * @param {(string|Buffer|object)} plainValue - plain secret value
+   * @returns {Buffer} Buffer containing value
+   */
+  _toBuffer (plainValue) {
+    if (plainValue instanceof Buffer) {
+      return plainValue
+    }
+
+    if (typeof plainValue === 'object') {
+      return Buffer.from(JSON.stringify(plainValue), 'utf-8')
+    }
+
+    return Buffer.from(`${plainValue}`, 'utf8')
+  }
+
   /**
    * Fetch Kubernetes secret manifest data.
    * @param {ExternalSecretSpec} spec - Kubernetes ExternalSecret spec.
@@ -108,16 +125,10 @@ class KVBackend extends AbstractBackend {
       }), {})
 
     const encodedEntries = Object.entries(plainValues)
-      .map(([name, plainValue]) => {
-        let bufferValue = plainValue
-        if (!(plainValue instanceof Buffer)) {
-          bufferValue = Buffer.from(`${plainValue}`, 'utf8')
-        }
-        return [
-          name,
-          bufferValue.toString('base64')
-        ]
-      })
+      .map(([name, plainValue]) => [
+        name,
+        this._toBuffer(plainValue).toString('base64')
+      ])
 
     return Object.fromEntries(encodedEntries)
   }

lib/backends/kv-backend.test.js

@@ -403,4 +403,31 @@ describe('kv-backend', () => {
       })
     })
   })
+
+  describe('base64 encoding', () => {
+    it('handles json objects', async () => {
+      kvBackend._get = sinon.stub()
+      kvBackend._get
+        .resolves(JSON.stringify({
+          textProperty: 'text',
+          jsonStringProperty: '{ "someKey": { "myText": "text" } }',
+          jsonProperty: { someKey: { myText: 'text' } }
+        }))
+
+      const manifestData = await kvBackend
+        .getSecretManifestData({
+          spec: {
+            dataFrom: ['test-key']
+          }
+        })
+
+      expect(kvBackend._get.calledOnce).to.equal(true)
+
+      expect(manifestData).deep.equals({
+        textProperty: 'dGV4dA==', // base 64 value of text
+        jsonStringProperty: 'eyAic29tZUtleSI6IHsgIm15VGV4dCI6ICJ0ZXh0IiB9IH0=', // base 64 value of: { "someKey": { "myText": "text" } }
+        jsonProperty: 'eyJzb21lS2V5Ijp7Im15VGV4dCI6InRleHQifX0=' // base 64 value of: {"someKey":{"myText":"text"}}
+      })
+    })
+  })
 })