feat(versioning-proxy): implement base contract and derived skeleton

contracts/standard/proxy/ArbitratorVersioningProxy.sol

@@ -0,0 +1,71 @@
+pragma solidity ^0.4.15;
+
+import "./VersioningProxy.sol";
+
+/**
+ *  @title ArbitratorVersioningProxy
+ *  @author Enrique Piqueras - <epiquerass@gmail.com>
+ *  @notice A contract derived from VersioningProxy to manage the deployment of new versions of an Arbitrator contract.
+ */
+ contract ArbitratorVersioningProxy is VersioningProxy {
+    /* Enums */
+
+
+
+    /* Structs */
+
+
+
+    /* Events */
+
+
+
+    /* Storage */
+
+
+
+    /* Modifiers */
+
+
+
+    /* Constructor */
+
+
+
+    /* Fallback */
+
+
+
+    /* External */
+
+
+
+    /* External Views */
+
+
+
+    /* Public */
+
+
+
+    /* Public Views */
+
+
+
+    /* Internal */
+
+
+
+    /* Internal Views */
+
+
+
+    /* Private */
+
+
+
+    /* Private Views */
+
+
+
+}

contracts/standard/proxy/VersioningProxy.sol

@@ -0,0 +1,128 @@
+pragma solidity ^0.4.15;
+
+/**
+ *  @title VersioningProxy
+ *  @author Enrique Piqueras - <epiquerass@gmail.com>
+ *  @notice A base contract for managing the deployment of versions of another contract.
+ */
+contract VersioningProxy {
+    /* Enums */
+
+
+
+    /* Structs */
+
+    struct Deployment {
+        bytes32 tag;
+        address _address;
+    }
+
+    /* Events */
+
+
+
+    /* Storage */
+
+    // Owner and Creation Metadata
+    address public owner = msg.sender;
+    uint256 public creationTime = now;
+
+    // Deployments
+    bytes32[] public tags; // We keep this so we can iterate over versions
+    mapping (bytes32 => address) public addresses;
+    Deployment public stable;
+
+    /* Modifiers */
+
+    /**
+     *  @dev Makes a function only callable by the owner of the contract.
+     */
+    modifier onlyOwner {
+        require(owner == msg.sender);
+        _;
+    }
+
+    /* Constructor */
+
+    /**
+     *  @notice Constructs the version proxy with the first version of the contract, `firstTag`, at `firstAddress`.
+     *  @param firstTag The version tag of the first version of the contract you are versioning.
+     *  @param firstAddress The address of the associated contract.
+     */
+    function VersioningProxy(bytes32 firstTag, address firstAddress) public {
+        publish(firstTag, firstAddress);
+    }
+
+    /* Fallback */
+
+
+
+    /* External */
+
+    /**
+     * @notice Rolls back 'stable' to the previous deployment, and returns true, if one exists, returns false otherwise.
+     */
+    function rollback() external onlyOwner returns(bool) {
+        uint256 tagsLen = tags.length;
+        if (tagsLen <= 2)
+            return false;
+
+        bytes32 prevTag = tags[tagsLen - 2];
+        setStable(prevTag);
+        return true;
+    }
+
+    /* External Views */
+
+    /**
+     * @notice Returns all deployed version tags.
+     */
+    function allTags() external view returns(bytes32[]) {
+        return tags;
+    }
+
+    /* Public */
+
+    /**
+     *  @notice Publishes a new version, `newTag`, at `newAddress`.
+     *  @param newTag The new version tag.
+     *  @param newAddress The address of the associated contract.
+     */
+    function publish(bytes32 newTag, address newAddress) public onlyOwner {
+        tags.push(newTag);
+        addresses[newTag] = newAddress;
+        stable = Deployment({tag: newTag, _address: newAddress});
+    }
+
+    /**
+     *  @notice Sets the value of stable to the address of `publishedTag`.
+     *  @param publishedTag The already published version tag.
+     */
+    function setStable(bytes32 publishedTag) public onlyOwner {
+        address _address = addresses[publishedTag];
+        require(_address != address(0)); // Throw if not published
+
+        stable = Deployment({tag: publishedTag, _address: _address});
+    }
+
+    /* Public Views */
+
+
+
+    /* Internal */
+
+
+
+    /* Internal Views */
+
+
+
+    /* Private */
+
+
+
+    /* Private Views */
+
+
+
+}