Server to client error messages

clients/typescript/src/satellite/process.ts

@@ -807,7 +807,11 @@ export class SatelliteProcess implements Satellite {
       throw satelliteError
     }
 
-    Log.warn(`an error occurred in satellite: ${satelliteError.message}`)
+    Log.warn(
+      `an error occurred in satellite: ${
+        SatelliteErrorCode[satelliteError.code]
+      } ${satelliteError.message}`
+    )
 
     this._handleOrThrowClientError(satelliteError)
   }

clients/typescript/src/util/proto.ts

@@ -244,7 +244,7 @@ export function serverErrorToSatelliteError(
 ): SatelliteError {
   return new SatelliteError(
     serverErrorToSatError[error.errorType],
-    'server error'
+    'Server error: ' + error.message
   )
 }
 

components/electric/lib/electric/satellite/protocol.ex

@@ -18,6 +18,7 @@ defmodule Electric.Satellite.Protocol do
   alias Electric.Replication.Shapes
   alias Electric.Replication.Shapes.ShapeRequest
   alias Electric.Satellite.Serialization
+  alias Electric.Satellite.Serialization.DataValidationError
   alias Electric.Satellite.ClientManager
   alias Electric.Satellite.WriteValidation
   alias Electric.Satellite.ClientReconnectionInfo
@@ -485,7 +486,7 @@ defmodule Electric.Satellite.Protocol do
         Telemetry.event(state, :bad_transaction)
 
         Logger.error(Exception.format(:error, e, __STACKTRACE__))
-        {:error, %SatErrorResp{error_type: :INVALID_REQUEST}}
+        {:error, %SatErrorResp{error_type: :INVALID_REQUEST, message: friendly_error_message(e)}}
     end
   end
 
@@ -1350,4 +1351,7 @@ defmodule Electric.Satellite.Protocol do
     do: Electric.Postgres.Dialect.SQLite
 
   defp decode_sql_dialect(:POSTGRES), do: Electric.Postgres.Dialect.Postgresql
+
+  defp friendly_error_message(%DataValidationError{} = error), do: Exception.message(error)
+  defp friendly_error_message(_), do: "unexpected error"
 end

components/electric/lib/electric/satellite/serialization.ex

@@ -1,6 +1,7 @@
 defmodule Electric.Satellite.Serialization do
   alias Electric.Satellite.Protocol
   alias Electric.Satellite.SatOpGone
+  alias Electric.Satellite.Serialization.DataValidationError
   alias Electric.Replication.Changes.Gone
   alias Electric.Postgres.Extension.SchemaCache
   alias Electric.Postgres.{Extension, Replication}
@@ -559,7 +560,7 @@ defmodule Electric.Satellite.Serialization do
   def decode_column_value!(val, :bool) when val in ["t", "f"], do: val
 
   def decode_column_value!(val, :bool) do
-    raise "Unexpected value for bool column: #{inspect(val)}"
+    raise DataValidationError, message: "Unexpected value for bool column: #{inspect(val)}"
   end
 
   def decode_column_value!(val, type) when type in [:text, :varchar] do
@@ -589,6 +590,11 @@ defmodule Electric.Satellite.Serialization do
     _ = Date.from_iso8601!(val)
 
     val
+  rescue
+    _ ->
+      reraise DataValidationError,
+              [message: "Unexpected value for :date column: #{inspect(val)}"],
+              __STACKTRACE__
   end
 
   def decode_column_value!(val, type) when type in [:float4, :float8] do
@@ -599,16 +605,25 @@ defmodule Electric.Satellite.Serialization do
   end
 
   def decode_column_value!(val, type) when type in [:int2, :int4, :int8] do
-    val
-    |> String.to_integer()
-    |> assert_valid_integer!(type)
+    case Integer.parse(val) do
+      {int, ""} ->
+        assert_valid_integer!(int, type)
+        val
 
-    val
+      _ ->
+        raise DataValidationError, message: "Non-integer value given for #{type} column: #{val}"
+    end
   end
 
   def decode_column_value!(val, type) when type in [:json, :jsonb] do
-    _ = Jason.decode!(val)
-    val
+    case Jason.decode(val) do
+      {:ok, _} ->
+        val
+
+      {:error, %Jason.DecodeError{} = error} ->
+        raise DataValidationError,
+          message: "Invalid JSON found in #{type} column: #{Exception.message(error)}"
+    end
   end
 
   def decode_column_value!(val, :time) do
@@ -628,36 +643,71 @@ defmodule Electric.Satellite.Serialization do
     _ = Time.from_iso8601!(val)
 
     val
+  rescue
+    _ ->
+      reraise DataValidationError,
+              [message: "Unexpected value for :time column: #{inspect(val)}"],
+              __STACKTRACE__
   end
 
   def decode_column_value!(val, :timestamp) do
-    # NaiveDateTime silently discards time zone offset if it is present in the string. But we want to reject such strings
-    # because values of type `timestamp` must not have an offset.
-    {:error, :missing_offset} = DateTime.from_iso8601(val)
+    case DateTime.from_iso8601(val) do
+      {:ok, _, _} ->
+        # NaiveDateTime silently discards time zone offset if it is present in the string. But we want to reject such strings
+        # because values of type `timestamp` must not have an offset.
+        raise DataValidationError,
+          message: "Unexpected offset provided for timestamp column: #{inspect(val)}"
 
-    dt = NaiveDateTime.from_iso8601!(val)
-    assert_valid_year!(dt.year)
+      {:error, :missing_offset} ->
+        dt = NaiveDateTime.from_iso8601!(val)
+        assert_valid_year!(dt.year)
 
-    val
+        val
+
+      {:error, :invalid_format} ->
+        raise DataValidationError,
+          message: "Unexpected format provided for timestamp column: #{inspect(val)}"
+    end
   end
 
   def decode_column_value!(val, :timestamptz) do
     # The offset of datetimes coming over the Satellite protocol MUST be 0.
-    {:ok, dt, 0} = DateTime.from_iso8601(val)
-    assert_valid_year!(dt.year)
+    case DateTime.from_iso8601(val) do
+      {:ok, dt, 0} ->
+        assert_valid_year!(dt.year)
 
-    val
+        val
+
+      {:ok, _, _} ->
+        raise DataValidationError,
+          message: "Non-zeo offset provided for timestamptz column: #{inspect(val)}"
+
+      {:error, :invalid_format} ->
+        raise DataValidationError,
+          message: "Unexpected format for timestamptz column: #{inspect(val)}"
+
+      {:error, :missing_offset} ->
+        raise DataValidationError,
+          message: "Missing offset in timestamptz column: #{inspect(val)}"
+    end
   end
 
   def decode_column_value!(val, :uuid) do
-    Electric.Utils.validate_uuid!(val)
+    case Electric.Utils.validate_uuid(val) do
+      {:ok, uuid} ->
+        uuid
+
+      :error ->
+        raise DataValidationError, message: "Unexpected value for uuid column: #{inspect(val)}"
+    end
   end
 
   def decode_column_value!(val, {:enum, typename, values}) do
     if val in values do
       val
     else
-      raise "Unexpected value #{inspect(val)} for enum type #{typename}"
+      raise DataValidationError,
+        message: "Unexpected value #{inspect(val)} for enum type #{typename}"
     end
   end
 
@@ -668,7 +718,7 @@ defmodule Electric.Satellite.Serialization do
         val
 
       _ ->
-        raise "Unexpected value for #{type} colum: #{inspect(val)}"
+        raise DataValidationError, message: "Unexpected value for #{type} column: #{inspect(val)}"
     end
   end
 
@@ -680,6 +730,9 @@ defmodule Electric.Satellite.Serialization do
   defp assert_valid_integer!(int, :int4) when int in @int4_range, do: :ok
   defp assert_valid_integer!(int, :int8) when int in @int8_range, do: :ok
 
+  defp assert_valid_integer!(int, type),
+    do: raise(DataValidationError, message: "Value out of range for #{type} column: #{int}")
+
   # Postgres[1] uses BC/AD suffixes to indicate whether the date is in the Common Era or precedes it. Postgres assumes year
   # 0 did not exist, so in its worldview '0001-12-31 BC' is immediately followed by '0001-01-01'.
   #
@@ -694,6 +747,9 @@ defmodule Electric.Satellite.Serialization do
   #   [2]: https://www.sqlite.org/lang_datefunc.html
   defp assert_valid_year!(year) when year in 1..9999, do: :ok
 
+  defp assert_valid_year!(year),
+    do: raise(DataValidationError, message: "Year out of range: #{year}")
+
   defp assert_valid_month!(month) when month in 1..12, do: :ok
 
   defp assert_valid_day!(day) when day in 1..31, do: :ok
@@ -731,7 +787,7 @@ defmodule Electric.Satellite.Serialization do
       end
 
     with :error <- conversion_result do
-      raise "Value for float4 column out of range: #{inspect(num)}"
+      raise DataValidationError, message: "Value for float4 column out of range: #{inspect(num)}"
     end
   end
 end

components/electric/lib/electric/satellite/serialization/data_validation_error.ex

@@ -0,0 +1,3 @@
+defmodule Electric.Satellite.Serialization.DataValidationError do
+  defexception [:message]
+end

components/electric/test/electric/satellite/serialization_test.exs

@@ -8,6 +8,7 @@ defmodule Electric.Satellite.SerializationTest do
   alias Electric.Postgres.{Lsn, Schema, Extension.SchemaCache}
   alias Electric.Replication.Changes.Transaction
   alias Electric.Satellite.Serialization
+  alias Electric.Satellite.Serialization.DataValidationError
   alias Electric.Postgres.MockSchemaLoader
 
   describe "map_to_row" do
@@ -262,7 +263,7 @@ defmodule Electric.Satellite.SerializationTest do
         try do
           Serialization.decode_record!(row, columns)
         rescue
-          _ -> :ok
+          DataValidationError -> :ok
         else
           val -> flunk("Expected decode_record!() to raise but it returned #{inspect(val)}")
         end