Adds support for inspecting a hex encoded public key (#7344)

* Adds support for inspecting a hex encoded public key

This adds support for inspecting hex encoded public keys to subkey. The
command looks like:

`subkey inspect --public 0xPUBLICHEX`

* Update client/cli/src/commands/utils.rs

Co-authored-by: André Silva <123550+andresilva@users.noreply.github.com>

Co-authored-by: André Silva <123550+andresilva@users.noreply.github.com>

substrate/client/cli/src/commands/inspect_key.rs

@@ -0,0 +1,121 @@
+// This file is part of Substrate.
+
+// Copyright (C) 2020 Parity Technologies (UK) Ltd.
+// SPDX-License-Identifier: Apache-2.0
+
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// 	http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+//! Implementation of the `inspect` subcommand
+
+use crate::{
+	utils::{self, print_from_uri, print_from_public}, KeystoreParams,
+	with_crypto_scheme, NetworkSchemeFlag, OutputTypeFlag, CryptoSchemeFlag, Error,
+};
+use structopt::StructOpt;
+/// The `inspect` command
+#[derive(Debug, StructOpt)]
+#[structopt(
+	name = "inspect-key",
+	about = "Gets a public key and a SS58 address from the provided Secret URI"
+)]
+pub struct InspectKeyCmd {
+	/// A Key URI to be inspected. May be a secret seed, secret URI
+	/// (with derivation paths and password), SS58, public URI or a hex encoded public key.
+	///
+	/// If it is a hex encoded public key, `--public` needs to be given as argument.
+	///
+	/// If the given value is a file, the file content will be used
+	/// as URI.
+	///
+	/// If omitted, you will be prompted for the URI.
+	uri: Option<String>,
+
+	/// Is the given `uri` a hex encoded public key?
+	#[structopt(long)]
+	public: bool,
+
+	#[allow(missing_docs)]
+	#[structopt(flatten)]
+	pub keystore_params: KeystoreParams,
+
+	#[allow(missing_docs)]
+	#[structopt(flatten)]
+	pub network_scheme: NetworkSchemeFlag,
+
+	#[allow(missing_docs)]
+	#[structopt(flatten)]
+	pub output_scheme: OutputTypeFlag,
+
+	#[allow(missing_docs)]
+	#[structopt(flatten)]
+	pub crypto_scheme: CryptoSchemeFlag,
+}
+
+impl InspectKeyCmd {
+	/// Run the command
+	pub fn run(&self) -> Result<(), Error> {
+		let uri = utils::read_uri(self.uri.as_ref())?;
+		let password = self.keystore_params.read_password()?;
+
+		if self.public {
+			with_crypto_scheme!(
+				self.crypto_scheme.scheme,
+				print_from_public(
+					&uri,
+					self.network_scheme.network.clone(),
+					self.output_scheme.output_type.clone(),
+				)
+			)?;
+		} else {
+			with_crypto_scheme!(
+				self.crypto_scheme.scheme,
+				print_from_uri(
+					&uri,
+					password,
+					self.network_scheme.network.clone(),
+					self.output_scheme.output_type.clone(),
+				)
+			);
+		}
+
+		Ok(())
+	}
+}
+
+#[cfg(test)]
+mod tests {
+	use super::*;
+	use structopt::StructOpt;
+
+	#[test]
+	fn inspect() {
+		let words =
+			"remember fiber forum demise paper uniform squirrel feel access exclude casual effort";
+		let seed = "0xad1fb77243b536b90cfe5f0d351ab1b1ac40e3890b41dc64f766ee56340cfca5";
+
+		let inspect =
+			InspectKeyCmd::from_iter(&["inspect-key", words, "--password", "12345"]);
+		assert!(inspect.run().is_ok());
+
+		let inspect = InspectKeyCmd::from_iter(&["inspect-key", seed]);
+		assert!(inspect.run().is_ok());
+	}
+
+	#[test]
+	fn inspect_public_key() {
+		let public = "0x12e76e0ae8ce41b6516cce52b3f23a08dcb4cfeed53c6ee8f5eb9f7367341069";
+
+		let inspect = InspectKeyCmd::from_iter(&["inspect-key", "--public", public]);
+		assert!(inspect.run().is_ok());
+	}
+}