Implement bottom up validation

cmd/config.go

@@ -221,15 +221,17 @@ func cfgFilesAdd(dir string) (cfg *Config, err error) {
 			}
 
 			pthName := strings.Split(f.Name(), ".")[0]
+			if err = config.ValidatePath(p); err != nil {
+				fmt.Printf("%s: %s\n", pth, err.Error())
+				continue
+			}
 			if err = cfg.AddPath(pthName, p); err != nil {
 				fmt.Printf("%s: %s\n", pth, err.Error())
 				continue
 			}
 
-			// TODO: Do bottom up validation
 			// For now, we assume that all chain files must have same filename as chain-id
 			// this is to ensure non-chain files (global config) does not get parsed into chain struct.
-			// Future work should implement bottom-up validation.
 			if c.ChainID != pthName {
 				fmt.Printf("Skipping non chain file: %s\n", f.Name())
 				continue
@@ -420,3 +422,121 @@ func overWriteConfig(cmd *cobra.Command, cfg *Config) error {
 	}
 	return err
 }
+
+// ValidatePath checks that a path is valid
+func (c *Config) ValidatePath(p *relayer.Path) (err error) {
+	if p.Src.Version == "" {
+		return fmt.Errorf("source must specify a version")
+	}
+	if err = c.ValidatePathEnd(p.Src); err != nil {
+		return err
+	}
+	if err = c.ValidatePathEnd(p.Dst); err != nil {
+		return err
+	}
+	if _, err = p.GetStrategy(); err != nil {
+		return err
+	}
+	if p.Src.Order != p.Dst.Order {
+		return fmt.Errorf("both sides must have same order ('ORDERED' or 'UNORDERED'), got src(%s) and dst(%s)",
+			p.Src.Order, p.Dst.Order)
+	}
+	return nil
+}
+
+// ValidatePathEnd validates provided pathend and returns error for invalid identifiers
+func (c *Config) ValidatePathEnd(pe *relayer.PathEnd) error {
+	if err := pe.ValidateBasic(); err != nil {
+		return err
+	}
+
+	chain, err := c.Chains.Get(pe.ChainID)
+	if err != nil {
+		return err
+	}
+
+	height, err := chain.QueryLatestHeight()
+	if err != nil {
+		return err
+	}
+
+	if pe.ClientID != "" {
+		if err := c.ValidateClient(chain, height, pe); err != nil {
+			return err
+		}
+
+		if pe.ConnectionID != "" {
+			if err := c.ValidateConnection(chain, height, pe); err != nil {
+				return err
+			}
+
+			if pe.ChannelID != "" {
+				if err := c.ValidateChannel(chain, height, pe); err != nil {
+					return err
+				}
+			}
+		}
+
+		if pe.ConnectionID == "" && pe.ChannelID != "" {
+			return fmt.Errorf("connectionID is not configured for the channel: %s", pe.ChannelID)
+		}
+	}
+
+	if pe.ClientID == "" && pe.ConnectionID != "" {
+		return fmt.Errorf("clientID is not configured for the connection: %s", pe.ConnectionID)
+	}
+
+	return nil
+}
+
+// ValidateClient validates client id in provided pathend
+func (c *Config) ValidateClient(chain *relayer.Chain, height int64, pe *relayer.PathEnd) error {
+	if err := pe.Vclient(); err != nil {
+		return err
+	}
+
+	_, err := chain.QueryClientState(height)
+	if err != nil {
+		return err
+	}
+
+	return nil
+}
+
+// ValidateConnection validates connection id in provided pathend
+func (c *Config) ValidateConnection(chain *relayer.Chain, height int64, pe *relayer.PathEnd) error {
+	if err := pe.Vconn(); err != nil {
+		return err
+	}
+
+	connection, err := chain.QueryConnection(height)
+	if err != nil {
+		return err
+	}
+
+	if connection.Connection.ClientId != pe.ClientID {
+		return fmt.Errorf("clientID of connection: %s didn't match with provided ClientID", pe.ConnectionID)
+	}
+
+	return nil
+}
+
+// ValidateChannel validates channel id in provided pathend
+func (c *Config) ValidateChannel(chain *relayer.Chain, height int64, pe *relayer.PathEnd) error {
+	if err := pe.Vchan(); err != nil {
+		return err
+	}
+
+	channel, err := chain.QueryChannel(height)
+	if err != nil {
+		return err
+	}
+
+	for _, connection := range channel.Channel.ConnectionHops {
+		if connection == pe.ConnectionID {
+			return nil
+		}
+	}
+
+	return fmt.Errorf("connectionID of channel: %s didn't match with provided ConnectionID", pe.ChannelID)
+}

cmd/paths.go

@@ -155,6 +155,9 @@ $ %s pth gen ibc-0 ibc-1 demo-path --unordered false --version ics20-2`, appName
 				path.GenSrcConnID()
 				path.GenSrcChanID()
 				path.GenDstChanID()
+				if err = config.ValidatePath(path); err != nil {
+					return err
+				}
 				if err = config.Paths.Add(pth, path); err != nil {
 					return err
 				}
@@ -166,6 +169,9 @@ $ %s pth gen ibc-0 ibc-1 demo-path --unordered false --version ics20-2`, appName
 				path.GenSrcConnID()
 				path.GenSrcChanID()
 				path.GenDstChanID()
+				if err = config.ValidatePath(path); err != nil {
+					return err
+				}
 				if err = config.Paths.Add(pth, path); err != nil {
 					return err
 				}
@@ -177,6 +183,9 @@ $ %s pth gen ibc-0 ibc-1 demo-path --unordered false --version ics20-2`, appName
 				path.GenSrcConnID()
 				path.GenSrcChanID()
 				path.GenDstChanID()
+				if err = config.ValidatePath(path); err != nil {
+					return err
+				}
 				if err = config.Paths.Add(pth, path); err != nil {
 					return err
 				}
@@ -225,6 +234,9 @@ $ %s pth gen ibc-0 ibc-1 demo-path --unordered false --version ics20-2`, appName
 					path.GenDstConnID()
 					path.GenSrcChanID()
 					path.GenDstChanID()
+					if err = config.ValidatePath(path); err != nil {
+						return err
+					}
 					if err = config.Paths.Add(pth, path); err != nil {
 						return err
 					}
@@ -236,6 +248,9 @@ $ %s pth gen ibc-0 ibc-1 demo-path --unordered false --version ics20-2`, appName
 				path.GenDstConnID()
 				path.GenSrcChanID()
 				path.GenDstChanID()
+				if err = config.ValidatePath(path); err != nil {
+					return err
+				}
 				if err = config.Paths.Add(pth, path); err != nil {
 					return err
 				}
@@ -289,6 +304,9 @@ $ %s pth gen ibc-0 ibc-1 demo-path --unordered false --version ics20-2`, appName
 					path.GenSrcChanID()
 					path.GenDstChanID()
 				}
+				if err = config.ValidatePath(path); err != nil {
+					return err
+				}
 				if err = config.Paths.Add(pth, path); err != nil {
 					return err
 				}
@@ -297,6 +315,9 @@ $ %s pth gen ibc-0 ibc-1 demo-path --unordered false --version ics20-2`, appName
 			default:
 				path.GenSrcChanID()
 				path.GenDstChanID()
+				if err = config.ValidatePath(path); err != nil {
+					return err
+				}
 				if err = config.Paths.Add(pth, path); err != nil {
 					return err
 				}
@@ -497,6 +518,10 @@ func fileInputPathAdd(file, name string) (cfg *Config, err error) {
 		return nil, err
 	}
 
+	if err = config.ValidatePath(p); err != nil {
+		return nil, err
+	}
+
 	if err = config.Paths.Add(name, p); err != nil {
 		return nil, err
 	}
@@ -631,6 +656,10 @@ func userInputPathAdd(src, dst, name string) (*Config, error) {
 		return nil, err
 	}
 
+	if err = config.ValidatePath(path); err != nil {
+		return nil, err
+	}
+
 	if err = config.Paths.Add(name, path); err != nil {
 		return nil, err
 	}

relayer/path.go

@@ -49,7 +49,6 @@ func (p Paths) MustGet(name string) *Path {
 
 // Add adds a path by its name
 func (p Paths) Add(name string, path *Path) error {
-	// TODO: Do bottomo up validation of path
 	if _, found := p[name]; found {
 		return fmt.Errorf("path with name %s already exists", name)
 	}