Responses are constructed from requests using MakeResponse, MakeError, and
MakeErrorf. This ensures the response is always paired with the correct ID,
makes cases where there is no ID more explicit at the usage site, and
consolidates the handling of error introspection across transports.
The logic for unpacking errors and assigning JSON-RPC response types was
previously duplicated in three places. Consolidate it in the types package for
the RPC subsystem.
* update test cases
Instead of having the exported Request and Response type expose the version
directly, delegate version injection to an unexported shim. We already had the
shim; this just boosts it to the top level and does a bit more checking.
* Check JSON-RPC version marker.
These are only ever used with the defaults, except in our own tests. A search
of cs.github.com shows no other callers.
The use in the test was solely to bug out the go-metrics package so its
goroutines don't trigger the leak checker. Use the package's own flag for that
purpose instead. Note that calling "Stop" on the metric helps, but is not
sufficient -- the Stop does not wait for its goroutine to exit.
The main change here is to use encoding/json to encode and decode RPC
parameters, rather than the custom tmjson package. This includes:
- Update the HTTP POST handler parameter handling.
- Add field tags to 64-bit integer types to get string encoding (to match amino/tmjson).
- Add marshalers to struct types that mention interfaces.
- Inject wrappers to decode interface arguments in RPC handlers.
The parameters for RPC GET requests are parsed from query arguments in the
request URL. Rework this code to remove the need for tmjson. The structure of a
call still requires reflection, and still works the same way as before, but the
code structure has been simplified and cleaned up a bit.
Points of note:
- Consolidate handling of pointer types, so we only need to dereference once.
- Reduce the number of allocations of reflective types.
- Report errors for unsupported types rather than returning untyped nil.
Update the tests as well. There was one test case that checked for an error on
a behaviour the OpenAPI docs explicitly demonstrates as supported, so I fixed
that test case, and also added some new ones for cases that weren't checked.
Related:
* Update e2e base Go image to 1.17 (to match config).
Require that RPC functions take a context as their first argument, and return
an error as either their only result, or the second of two results.
This does not change how functions are dispatched, but will make it a little
easier to make more invasive changes in the near future.
Instead of taking a comma-separated string of parameter names, take each
parameter name as a separate argument. Now that we no longer have an extra flag
for caching, this fits nicely into a variadic trailer.
* Update all usage of NewRPCFunc and NewWSRPCFunc.
Rather than installing two separate panic handlers, defer the bookkeeping
separately from recovery, and lift the delegated handler call out to the top
level of the wrapper.
Also: Regularize the server middleware wrappers.
Add writeRPCResponse and writeHTTPResponse helpers, that handle the way RPC
responses are written to HTTP replies. These replace the exported helpers.
Visible effects:
- JSON results are now marshaled without indentation.
- HTTP status codes are now normalized.
- Cache control headers are no longer set.
Details:
- When writing a response to a URL (GET) request, do not marshal the whole
JSON-RPC object into the body, only encode the result or the error object.
This is a user-visible change.
- Do not change the HTTP status code for RPC errors. The RPC error already
reports what went wrong, the HTTP status should only report problems with the
HTTP transaction itself. This is a user-visible change.
- Encode JSON without indentation in POST response bodies. This is mainly cosmetic
but saves quite a bit of response data. Indent is still applied to GET responses to make
life easier for code examples.
- Remove an obsolete TODO about reporting an HTTP error on websocket upgrade.
Nothing needed to change; the upgrader already reports an error.
- Report an HTTP error when starting the server loop fails.
- Improve logging for encoding errors.
- Log less aggressively.
We should not set cache-control headers on RPC responses. HTTP caching
interacts poorly with resources that are expected to change frequently, or
whose rate of change is unpredictable.
More subtly, all calls to the POST endpoint use the same URL, which means a
cacheable response from one call may actually "hide" an uncacheable response
from a subsequent one. This is less of a problem for the GET endpoints, but
that means the behaviour of RPCs varies depending on which HTTP method your
client happens to use. Websocket requests were already marked statically
uncacheable, adding yet a third combination.
To address this:
- Stop setting cache-control headers.
- Update the tests that were checking for those headers.
- Remove the flags to request cache-control.
Apart from affecting the HTTP response headers, this change does not modify the
behaviour of any of the RPC methods.
* Rename rpctypes.Context to CallInfo.
Add methods to attach and recover this value from a context.Context.
* Rework RPC method handlers to accept "real" contexts.
- Replace *rpctypes.Context arguments with context.Context.
- Update usage of RPC context fields to use CallInfo.
No functional changes.
- Pull out a some helper code to simplify the control flow within the body of
the HTTP request handler.
- Front-load the URL path check so it does not get repeated for each request.
* Update Caller interface and its documentation.
* Rework MapToRequest as ParamsToRequest.
The old interface returned the result as well as populating it. Nothing was
using this, so drop the duplicated value from the return signature. Clarify the
documentation on the Caller type.
Rework the MapToRequest helper to take an arbitrary value instead of only a
map. This is groundwork for getting rid of the custom marshaling code. For now,
however, the implementation preserves the existing behaviour for the map, until
we can replace those.
These two interfaces are identical, and besides HTTPClient being confusingly
named, all but one location uses Caller. Update that one location, and drop the
redundant interface.
Apart from the tests for the websocket client, positional parameters are not
used by RPC clients. The server supports both arrays and objects, but the
client only needs to provide one or the other.
The JSON-RPC endpoint accepts requests via URL (GET) and JSON (POST). There is
no real point in having client libraries for both modes.
A search of the SDK and on GitHub suggests that most usage is via the JSON
client (via the New constructor) or websocket (NewWS), and the only uses I
found of the NewURI client constructor are in copies of our own test code.
This does not change the functionalitiy of the server, so curl and other
URL-based clients in other languages will still function as before.
This continues the push of plumbing contexts through tendermint. I
attempted to find all goroutines in the production code (non-test) and
made sure that these threads would exit when their contexts were
canceled, and I believe this PR does that.
I think calling os.Exit at arbitrary points is _bad_ and is good to
delete. I think panics in the case of data courruption have a chance
of providing useful information.
The code in the Tendermint repository makes heavy use of import aliasing.
This is made necessary by our extensive reuse of common base package names, and
by repetition of similar names across different subdirectories.
Unfortunately we have not been very consistent about which packages we alias in
various circumstances, and the aliases we use vary. In the spirit of the advice
in the style guide and https://github.com/golang/go/wiki/CodeReviewComments#imports,
his change makes an effort to clean up and normalize import aliasing.
This change makes no API or behavioral changes. It is a pure cleanup intended
o help make the code more readable to developers (including myself) trying to
understand what is being imported where.
Only unexported names have been modified, and the changes were generated and
applied mechanically with gofmt -r and comby, respecting the lexical and
syntactic rules of Go. Even so, I did not fix every inconsistency. Where the
changes would be too disruptive, I left it alone.
The principles I followed in this cleanup are:
- Remove aliases that restate the package name.
- Remove aliases where the base package name is unambiguous.
- Move overly-terse abbreviations from the import to the usage site.
- Fix lexical issues (remove underscores, remove capitalization).
- Fix import groupings to more closely match the style guide.
- Group blank (side-effecting) imports and ensure they are commented.
- Add aliases to multiple imports with the same base package name.
* rpc: Strip down the base RPC client interface.
Prior to this change, the RPC client interface requires implementing the entire
Service interface, but most of the methods of Service are not needed by the
concrete clients. Dissociate the Client interface from the Service interface.
- Extract only those methods of Service that are necessary to make the existing
clients work.
- Update the clients to combine Start/Onstart and Stop/OnStop. This does not
change what the clients do to start or stop. Only the websocket clients make
use of this functionality anyway.
The websocket implementation uses some plumbing from the BaseService helper.
We should be able to excising that entirely, but the current interface
dependencies among the clients would require a much larger change, and one
that leaks into other (non-RPC) packages.
As a less-invasive intermediate step, preserve the existing client behaviour
(and tests) by extracting the necessary subset of the BaseService
functionality to an analogous RunState helper for clients. I plan to obsolete
that type in a future PR, but for now this makes a useful waypoint.
Related:
- Clean up client implementations.
- Update mocks.
EDIT: Updated, see [comment below]( https://github.com/tendermint/tendermint/pull/6785#issuecomment-897793175)
This change adds a sketch of the `Debug` mode.
This change adds a `Debug` struct to the node package. This `Debug` struct is intended to be created and started by a command in the `cmd` directory. The `Debug` struct runs the RPC server on the data directories: both the state store and the block store.
This change required a good deal of refactoring. Namely, a new `rpc.go` file was added to the `node` package. This file encapsulates functions for starting RPC servers used by nodes. A potential additional change is to further factor this code into shared code _in_ the `rpc` package.
Minor API tweaks were also made that seemed appropriate such as the mechanism for fetching routes from the `rpc/core` package.
Additional work is required to register the `Debug` service as a command in the `cmd` directory but I am looking for feedback on if this direction seems appropriate before diving much further.
closes: #5908
## Description
Internalize some libs. This reduces the amount ot public API tendermint is supporting. The moved libraries are mainly ones that are used within Tendermint-core.
M. J. Fromberger
Sam Kleinman
JayT106
Sharad Chand
Callum Waters
William Banfield
Aleksandr Bezobchuk
Marko
Ismail Khoffi
Frojdi Dymylja
Anton Kaliaev