private Credential constructGcsCredential()

in priam/src/main/java/com/netflix/priam/google/GoogleEncryptedFileSystem.java [125:176]
40 lines of code
6 McCabe index (conditional complexity)

    private Credential constructGcsCredential() throws Exception {

        if (this.credential != null) {
            return this.credential;
        }

        synchronized (this) {
            if (this.credential == null) {

                String service_acct_email =
                        new String(this.gcsCredential.getValue(KEY.GCS_SERVICE_ID));

                if (this.config.getGcsServiceAccountPrivateKeyLoc() == null
                        || this.config.getGcsServiceAccountPrivateKeyLoc().isEmpty()) {
                    throw new NullPointerException(
                            "Fast property for the the GCS private key file is null/empty.");
                }

                // Take the encrypted private key, decrypted into an in-transit file which is passed
                // to GCS
                File gcsPrivateKeyHandle =
                        new File(this.config.getGcsServiceAccountPrivateKeyLoc() + ".output");

                ByteArrayOutputStream byteos = new ByteArrayOutputStream();

                byte[] gcsPrivateKeyPlainText =
                        this.gcsCredential.getValue(KEY.GCS_PRIVATE_KEY_LOC);
                try (BufferedOutputStream bos =
                        new BufferedOutputStream(new FileOutputStream(gcsPrivateKeyHandle))) {
                    byteos.write(gcsPrivateKeyPlainText);
                    byteos.writeTo(bos);
                } catch (IOException e) {
                    throw new IOException(
                            "Exception when writing decrypted gcs private key value to disk.", e);
                }

                Collection<String> scopes = new ArrayList<>(1);
                scopes.add(StorageScopes.DEVSTORAGE_READ_ONLY);
                // Cryptex decrypted service account key derive from the GCS console
                this.credential =
                        new GoogleCredential.Builder()
                                .setTransport(this.httpTransport)
                                .setJsonFactory(JSON_FACTORY)
                                .setServiceAccountId(service_acct_email)
                                .setServiceAccountScopes(scopes)
                                .setServiceAccountPrivateKeyFromP12File(gcsPrivateKeyHandle)
                                .build();
            }
        }

        return this.credential;
    }