From b478cd1bcb4756b20f7f4b15fcf81f23e1a60a02 Mon Sep 17 00:00:00 2001 From: Michael Muré Date: Fri, 14 Sep 2018 12:40:31 +0200 Subject: graphql: update gqlgen to 0.5.1 fix #6 --- .../github.com/99designs/gqlgen/handler/graphql.go | 283 +++++++++++++++++++++ 1 file changed, 283 insertions(+) create mode 100644 vendor/github.com/99designs/gqlgen/handler/graphql.go (limited to 'vendor/github.com/99designs/gqlgen/handler/graphql.go') diff --git a/vendor/github.com/99designs/gqlgen/handler/graphql.go b/vendor/github.com/99designs/gqlgen/handler/graphql.go new file mode 100644 index 00000000..9d222826 --- /dev/null +++ b/vendor/github.com/99designs/gqlgen/handler/graphql.go @@ -0,0 +1,283 @@ +package handler + +import ( + "context" + "encoding/json" + "fmt" + "io" + "net/http" + "strings" + + "github.com/99designs/gqlgen/complexity" + "github.com/99designs/gqlgen/graphql" + "github.com/gorilla/websocket" + "github.com/hashicorp/golang-lru" + "github.com/vektah/gqlparser" + "github.com/vektah/gqlparser/ast" + "github.com/vektah/gqlparser/gqlerror" + "github.com/vektah/gqlparser/validator" +) + +type params struct { + Query string `json:"query"` + OperationName string `json:"operationName"` + Variables map[string]interface{} `json:"variables"` +} + +type Config struct { + cacheSize int + upgrader websocket.Upgrader + recover graphql.RecoverFunc + errorPresenter graphql.ErrorPresenterFunc + resolverHook graphql.FieldMiddleware + requestHook graphql.RequestMiddleware + complexityLimit int +} + +func (c *Config) newRequestContext(doc *ast.QueryDocument, query string, variables map[string]interface{}) *graphql.RequestContext { + reqCtx := graphql.NewRequestContext(doc, query, variables) + if hook := c.recover; hook != nil { + reqCtx.Recover = hook + } + + if hook := c.errorPresenter; hook != nil { + reqCtx.ErrorPresenter = hook + } + + if hook := c.resolverHook; hook != nil { + reqCtx.ResolverMiddleware = hook + } + + if hook := c.requestHook; hook != nil { + reqCtx.RequestMiddleware = hook + } + + return reqCtx +} + +type Option func(cfg *Config) + +func WebsocketUpgrader(upgrader websocket.Upgrader) Option { + return func(cfg *Config) { + cfg.upgrader = upgrader + } +} + +func RecoverFunc(recover graphql.RecoverFunc) Option { + return func(cfg *Config) { + cfg.recover = recover + } +} + +// ErrorPresenter transforms errors found while resolving into errors that will be returned to the user. It provides +// a good place to add any extra fields, like error.type, that might be desired by your frontend. Check the default +// implementation in graphql.DefaultErrorPresenter for an example. +func ErrorPresenter(f graphql.ErrorPresenterFunc) Option { + return func(cfg *Config) { + cfg.errorPresenter = f + } +} + +// ComplexityLimit sets a maximum query complexity that is allowed to be executed. +// If a query is submitted that exceeds the limit, a 422 status code will be returned. +func ComplexityLimit(limit int) Option { + return func(cfg *Config) { + cfg.complexityLimit = limit + } +} + +// ResolverMiddleware allows you to define a function that will be called around every resolver, +// useful for tracing and logging. +func ResolverMiddleware(middleware graphql.FieldMiddleware) Option { + return func(cfg *Config) { + if cfg.resolverHook == nil { + cfg.resolverHook = middleware + return + } + + lastResolve := cfg.resolverHook + cfg.resolverHook = func(ctx context.Context, next graphql.Resolver) (res interface{}, err error) { + return lastResolve(ctx, func(ctx context.Context) (res interface{}, err error) { + return middleware(ctx, next) + }) + } + } +} + +// RequestMiddleware allows you to define a function that will be called around the root request, +// after the query has been parsed. This is useful for logging and tracing +func RequestMiddleware(middleware graphql.RequestMiddleware) Option { + return func(cfg *Config) { + if cfg.requestHook == nil { + cfg.requestHook = middleware + return + } + + lastResolve := cfg.requestHook + cfg.requestHook = func(ctx context.Context, next func(ctx context.Context) []byte) []byte { + return lastResolve(ctx, func(ctx context.Context) []byte { + return middleware(ctx, next) + }) + } + } +} + +// CacheSize sets the maximum size of the query cache. +// If size is less than or equal to 0, the cache is disabled. +func CacheSize(size int) Option { + return func(cfg *Config) { + cfg.cacheSize = size + } +} + +const DefaultCacheSize = 1000 + +func GraphQL(exec graphql.ExecutableSchema, options ...Option) http.HandlerFunc { + cfg := Config{ + cacheSize: DefaultCacheSize, + upgrader: websocket.Upgrader{ + ReadBufferSize: 1024, + WriteBufferSize: 1024, + }, + } + + for _, option := range options { + option(&cfg) + } + + var cache *lru.Cache + if cfg.cacheSize > 0 { + var err error + cache, err = lru.New(DefaultCacheSize) + if err != nil { + // An error is only returned for non-positive cache size + // and we already checked for that. + panic("unexpected error creating cache: " + err.Error()) + } + } + + return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) { + if r.Method == http.MethodOptions { + w.Header().Set("Allow", "OPTIONS, GET, POST") + w.WriteHeader(http.StatusOK) + return + } + + if strings.Contains(r.Header.Get("Upgrade"), "websocket") { + connectWs(exec, w, r, &cfg) + return + } + + var reqParams params + switch r.Method { + case http.MethodGet: + reqParams.Query = r.URL.Query().Get("query") + reqParams.OperationName = r.URL.Query().Get("operationName") + + if variables := r.URL.Query().Get("variables"); variables != "" { + if err := jsonDecode(strings.NewReader(variables), &reqParams.Variables); err != nil { + sendErrorf(w, http.StatusBadRequest, "variables could not be decoded") + return + } + } + case http.MethodPost: + if err := jsonDecode(r.Body, &reqParams); err != nil { + sendErrorf(w, http.StatusBadRequest, "json body could not be decoded: "+err.Error()) + return + } + default: + w.WriteHeader(http.StatusMethodNotAllowed) + return + } + w.Header().Set("Content-Type", "application/json") + + var doc *ast.QueryDocument + if cache != nil { + val, ok := cache.Get(reqParams.Query) + if ok { + doc = val.(*ast.QueryDocument) + } + } + if doc == nil { + var qErr gqlerror.List + doc, qErr = gqlparser.LoadQuery(exec.Schema(), reqParams.Query) + if len(qErr) > 0 { + sendError(w, http.StatusUnprocessableEntity, qErr...) + return + } + if cache != nil { + cache.Add(reqParams.Query, doc) + } + } + + op := doc.Operations.ForName(reqParams.OperationName) + if op == nil { + sendErrorf(w, http.StatusUnprocessableEntity, "operation %s not found", reqParams.OperationName) + return + } + + if op.Operation != ast.Query && r.Method == http.MethodGet { + sendErrorf(w, http.StatusUnprocessableEntity, "GET requests only allow query operations") + return + } + + vars, err := validator.VariableValues(exec.Schema(), op, reqParams.Variables) + if err != nil { + sendError(w, http.StatusUnprocessableEntity, err) + return + } + reqCtx := cfg.newRequestContext(doc, reqParams.Query, vars) + ctx := graphql.WithRequestContext(r.Context(), reqCtx) + + defer func() { + if err := recover(); err != nil { + userErr := reqCtx.Recover(ctx, err) + sendErrorf(w, http.StatusUnprocessableEntity, userErr.Error()) + } + }() + + if cfg.complexityLimit > 0 { + queryComplexity := complexity.Calculate(exec, op, vars) + if queryComplexity > cfg.complexityLimit { + sendErrorf(w, http.StatusUnprocessableEntity, "query has complexity %d, which exceeds the limit of %d", queryComplexity, cfg.complexityLimit) + return + } + } + + switch op.Operation { + case ast.Query: + b, err := json.Marshal(exec.Query(ctx, op)) + if err != nil { + panic(err) + } + w.Write(b) + case ast.Mutation: + b, err := json.Marshal(exec.Mutation(ctx, op)) + if err != nil { + panic(err) + } + w.Write(b) + default: + sendErrorf(w, http.StatusBadRequest, "unsupported operation type") + } + }) +} + +func jsonDecode(r io.Reader, val interface{}) error { + dec := json.NewDecoder(r) + dec.UseNumber() + return dec.Decode(val) +} + +func sendError(w http.ResponseWriter, code int, errors ...*gqlerror.Error) { + w.WriteHeader(code) + b, err := json.Marshal(&graphql.Response{Errors: errors}) + if err != nil { + panic(err) + } + w.Write(b) +} + +func sendErrorf(w http.ResponseWriter, code int, format string, args ...interface{}) { + sendError(w, code, &gqlerror.Error{Message: fmt.Sprintf(format, args...)}) +} -- cgit