/// <summary>Runs this API with the given JSON payload and a signee.</summary>
public override JSObject Run(JSObject payload, Signee signer, Location at)
{
// First we need to build a JWS if we have a payload.
if (payload != null)
{
// Build the JWS.
// It has no header and no protected header because:
// - The header originates from the signer
// (i.e. it adds the 'entity', 'pk' or 'device' field to the header)
// - Protected header is only ever used by root nodes forwarding to other root nodes.
payload = JWS.Build(null, null, payload, signer);
}
// Now perform the HTTP request (get/post depending on if we have a payload or not).
HttpResponse req;
JSObject result = Http.Request(FullPath(at), payload, out req);
if (!req.Ok)
{
// It errored! Result is either null or an error description.
throw new Exception("API Errored! " + (result != null));
}
// Has it got a Sequence header?
string seq = req.Sequence;
if (seq != null && signer != null)
{
// Yes - update the signer:
signer.Sequence = seq;
}
return(result);
}
/// <summary>Runs the given function at this location.</summary>
public JSObject Run(string function, JSObject payload, Signee signer)
{
// Get the function from the API:
ApiObject func = Api[function];
if (func == null)
{
// Function not found.
throw new Exception("The function '" + function + "' is not a valid function for this API.");
}
// Try running it:
return(func.Run(payload, signer, this));
}
/// <summary>Runs this API with the given JSON payload and a signee.</summary>
public virtual JSObject Run(JSObject payload, Signee signer, Location at)
{
// This occurs when the user, for example, attempted to 'run' an API type.
// An example of a type is error/field/invalid - an error object description.
throw new Exception("This only works on Api functions.");
}
/// <summary>Builds a JWS from JSON objects.</summary>
public static JSObject Build(JSObject header, JSObject pHeader, JSObject payload, Signee signer)
{
// Get the time in ms:
ulong timeMS = Time.UnixTimeMs;
// Generate an ID:
string id = RandomString.Hex(20) + "@" + timeMS;
// Sign the ID. This is the public signature which will appear in the public change log:
string pubSig64 = signer.Sign(id);
if (header == null)
{
// The header is almost always null; create a new one:
header = new JSArray();
}
if (pHeader == null)
{
// The protected header is almost always null; create a new one:
pHeader = new JSArray();
}
// Ask the signer to populate the JWS header - for example, putting the entity endpoint in there:
signer.GetJwsHeader(header);
// Add the pubsig, ID and sequence code to our protected header:
pHeader["id"] = new JSValue(id);
pHeader["pubsig"] = new JSValue(pubSig64);
if (!string.IsNullOrEmpty(signer.Sequence))
{
// Apply the sequence code:
pHeader["seq"] = new JSValue(signer.Sequence);
}
// Base64 both strings:
string payload64 = Base64.Encode(JSON.Stringify(payload));
string pHeader64 = Base64.Encode(JSON.Stringify(pHeader));
if (payload64 == "e30=")
{
// Strip the {} case (doesn't happen with the protected header).
payload64 = "";
}
// Sign the base64 strings combined with a .:
string signature64 = signer.Sign(pHeader64 + "." + payload64);
// Build the JWS itself:
JSArray jws = new JSArray();
// Add the values:
jws["header"] = header;
jws["payload"] = new JSValue(payload64);
jws["protected"] = new JSValue(pHeader64);
jws["signature"] = new JSValue(signature64);
return(jws);
}
