public SigningServicePrivateKey getPrivateKey()

in jsign-core/src/main/java/net/jsign/jca/GoogleCloudSigningService.java [110:154]
35 lines of code
8 McCabe index (conditional complexity)

    public SigningServicePrivateKey getPrivateKey(String alias) throws UnrecoverableKeyException {
        // check if the alias is absolute or relative to the keyring
        if (!alias.startsWith("projects/")) {
            alias = keyring + "/cryptoKeys/" + alias;
        }

        if (keys.containsKey(alias)) {
            return keys.get(alias);
        }

        String algorithm;

        try {
            if (alias.contains("cryptoKeyVersions")) {
                // full key with version specified
                if (alias.contains(":")) {
                    // algorithm appended to the alias
                    algorithm = alias.substring(alias.indexOf(':') + 1) + "_SIGN";
                    alias = alias.substring(0, alias.indexOf(':'));
                } else {
                    Map<String, ?> response = client.get(alias);
                    algorithm = (String) response.get("algorithm");
                }
            } else {
                // key version not specified, find the most recent
                Map<String, ?> response = client.get(alias + "/cryptoKeyVersions?filter=state%3DENABLED");
                Object[] cryptoKeyVersions = (Object[]) response.get("cryptoKeyVersions");
                if (cryptoKeyVersions == null || cryptoKeyVersions.length == 0) {
                    throw new UnrecoverableKeyException("Unable to fetch Google Cloud private key '" + alias + "', no version found");
                }

                Map<String, ?> cryptoKeyVersion = (Map) cryptoKeyVersions[cryptoKeyVersions.length - 1];
                alias = (String) cryptoKeyVersion.get("name");
                algorithm = (String) cryptoKeyVersion.get("algorithm");
            }
        } catch (IOException e) {
            throw (UnrecoverableKeyException) new UnrecoverableKeyException("Unable to fetch Google Cloud private key '" + alias + "'").initCause(e);
        }

        algorithm = algorithm.substring(0, algorithm.indexOf("_")); // RSA_SIGN_PKCS1_2048_SHA256 -> RSA

        SigningServicePrivateKey key = new SigningServicePrivateKey(alias, algorithm);
        keys.put(alias, key);
        return key;
    }