change to go modules

update README.md
whole batch functions can error
renaming stuff

Author: robinbraemer

.travis.yml

@@ -5,16 +5,16 @@
 This is an implementation of [Facebook's DataLoader](https://github.com/facebook/dataloader) in Golang.
 
 ## Install
-`go get -u github.com/graph-gophers/dataloader`
+`go get -u go.dribs.io/dataloader`
 
 ## Usage
 ```go
 // setup batch function
-batchFn := func(ctx context.Context, keys dataloader.Keys) []*dataloader.Result {
+batchFn := func(ctx context.Context, keys dataloader.Keys) ([]*dataloader.Result, error) {
   var results []*dataloader.Result
   // do some aync work to get data for specified keys
   // append to this list resolved values
-  return results
+  return results, nil
 }
 
 // create Loader with an in-memory cache
@@ -36,9 +36,6 @@ if err != nil {
 log.Printf("value: %#v", result)
 ```
 
-### Don't need/want to use context?
-You're welcome to install the v1 version of this library.
-
 ## Cache
 This implementation contains a very basic cache that is intended only to be used for short lived DataLoaders (i.e. DataLoaders that ony exsist for the life of an http request). You may use your own implementation if you want.
 

Godeps/Godeps.json

@@ -27,11 +27,12 @@ type Interface interface {
 	Prime(ctx context.Context, key Key, value interface{}) Interface
 }
 
-// BatchFunc is a function, which when given a slice of keys (string), returns a slice of `results`.
+// BatchFunc is a function, which when given a slice of keys (string), returns an slice of `results`.
 // It's important that the length of the input keys matches the length of the output results.
 //
 // The keys passed to this function are guaranteed to be unique
-type BatchFunc func(context.Context, Keys) []*Result
+// Returning error saying the whole batch errored.
+type BatchFunc func(context.Context, Keys) ([]*Result, error)
 
 // Result is the data structure that a BatchFunc returns.
 // It contains the resolved data, and any errors that may have occurred while fetching the data.
@@ -405,6 +406,7 @@ func (b *batcher) batch(originalContext context.Context) {
 		keys     = make(Keys, 0)
 		reqs     = make([]*batchRequest, 0)
 		items    = make([]*Result, 0)
+		err      error // indicating error for whole batch
 		panicErr interface{}
 	)
 
@@ -429,7 +431,7 @@ func (b *batcher) batch(originalContext context.Context) {
 				log.Printf("Dataloader: Panic received in batch function:: %v\n%s", panicErr, buf)
 			}
 		}()
-		items = b.batchFn(ctx, keys)
+		items, err = b.batchFn(ctx, keys)
 	}()
 
 	if panicErr != nil {
@@ -440,6 +442,15 @@ func (b *batcher) batch(originalContext context.Context) {
 		return
 	}
 
+	if err != nil {
+		err := &Result{Error: err}
+		for _, req := range reqs {
+			req.channel <- err
+			close(req.channel)
+		}
+		return
+	}
+
 	if len(items) != len(keys) {
 		err := &Result{Error: fmt.Errorf(`
 			The batch function supplied did not return an array of responses

Godeps/Readme

@@ -7,7 +7,7 @@ import (
 	"fmt"
 
 	lru "github.com/hashicorp/golang-lru"
-	"github.com/nicksrandall/dataloader"
+	"go.dribs.io/dataloader"
 )
 
 // Cache implements the dataloader.Cache interface
@@ -58,11 +58,11 @@ func main() {
 	fmt.Printf("identity: %s\n", result)
 }
 
-func batchFunc(_ context.Context, keys dataloader.Keys) []*dataloader.Result {
+func batchFunc(_ context.Context, keys dataloader.Keys) ([]*dataloader.Result, error) {
 	var results []*dataloader.Result
 	// do some pretend work to resolve keys
 	for _, key := range keys {
 		results = append(results, &dataloader.Result{key.String(), nil})
 	}
-	return results
+	return results, nil
 }

Gopkg.lock

@@ -4,7 +4,7 @@ import (
 	"context"
 	"fmt"
 
-	"github.com/nicksrandall/dataloader"
+	"go.dribs.io/dataloader"
 )
 
 func main() {
@@ -20,11 +20,11 @@ func main() {
 	fmt.Printf("identity: %s\n", result)
 }
 
-func batchFunc(_ context.Context, keys dataloader.Keys) []*dataloader.Result {
+func batchFunc(_ context.Context, keys dataloader.Keys) ([]*dataloader.Result, error) {
 	var results []*dataloader.Result
 	// do some pretend work to resolve keys
 	for _, key := range keys {
 		results = append(results, &dataloader.Result{key.String(), nil})
 	}
-	return results
+	return results, nil
 }

Gopkg.toml

@@ -7,8 +7,8 @@ import (
 	"fmt"
 	"time"
 
-	"github.com/nicksrandall/dataloader"
-	cache "github.com/patrickmn/go-cache"
+	"github.com/patrickmn/go-cache"
+	"go.dribs.io/dataloader"
 )
 
 // Cache implements the dataloader.Cache interface
@@ -59,11 +59,11 @@ func main() {
 	fmt.Printf("identity: %s\n", result)
 }
 
-func batchFunc(_ context.Context, keys dataloader.Keys) []*dataloader.Result {
+func batchFunc(_ context.Context, keys dataloader.Keys) ([]*dataloader.Result, error) {
 	var results []*dataloader.Result
 	// do some pretend work to resolve keys
 	for _, key := range keys {
 		results = append(results, &dataloader.Result{key.String(), nil})
 	}
-	return results
+	return results, nil
 }

README.md

@@ -0,0 +1,12 @@
+module go.dribs.io/dataloader
+
+go 1.12
+
+require (
+	github.com/hashicorp/golang-lru v0.0.0-20160813221303-0a025b7e63ad
+	github.com/nicksrandall/dataloader v5.0.0+incompatible
+	github.com/opentracing/opentracing-go v1.0.2
+	github.com/patrickmn/go-cache v2.1.0+incompatible
+	github.com/stretchr/testify v1.3.0 // indirect
+	golang.org/x/net v0.0.0-20171129192339-a8b929477797 // indirect
+)

inMemoryCache.go renamed to cache_inmemory.go

@@ -0,0 +1,17 @@
+github.com/davecgh/go-spew v1.1.0 h1:ZDRjVQ15GmhC3fiQ8ni8+OwkZQO4DARzQgrnXU1Liz8=
+github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/hashicorp/golang-lru v0.0.0-20160813221303-0a025b7e63ad h1:eMxs9EL0PvIGS9TTtxg4R+JxuPGav82J8rA+GFnY7po=
+github.com/hashicorp/golang-lru v0.0.0-20160813221303-0a025b7e63ad/go.mod h1:/m3WP610KZHVQ1SGc6re/UDhFvYD7pJ4Ao+sR/qLZy8=
+github.com/nicksrandall/dataloader v5.0.0+incompatible h1:uX/GNCB35GQET9x6scOxL5mgoCL2FWU1uCX0YHwFz4k=
+github.com/nicksrandall/dataloader v5.0.0+incompatible/go.mod h1:ffw+n6o2gnZpT4lkSLF6W1+aDf6WIHZwWcwLF3/jJSo=
+github.com/opentracing/opentracing-go v1.0.2 h1:3jA2P6O1F9UOrWVpwrIo17pu01KWvNWg4X946/Y5Zwg=
+github.com/opentracing/opentracing-go v1.0.2/go.mod h1:UkNAQd3GIcIGf0SeVgPpRdFStlNbqXla1AfSYxPUl2o=
+github.com/patrickmn/go-cache v2.1.0+incompatible h1:HRMgzkcYKYpi3C8ajMPV8OFXaaRUnok+kx1WdO15EQc=
+github.com/patrickmn/go-cache v2.1.0+incompatible/go.mod h1:3Qf8kWWT7OJRJbdiICTKqZju1ZixQ/KpMGzzAfe6+WQ=
+github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
+github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
+github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
+github.com/stretchr/testify v1.3.0 h1:TivCn/peBQ7UY8ooIcPgZFpTNSz0Q2U6UrFlUfqbe0Q=
+github.com/stretchr/testify v1.3.0/go.mod h1:M5WIy9Dh21IEIfnGCwXGc5bZfKNJtfHm1UVUgZn+9EI=
+golang.org/x/net v0.0.0-20171129192339-a8b929477797 h1:LwuzaILeZdnfjwbkFDc5ex0Us4o0k6PlbZuThgT8a68=
+golang.org/x/net v0.0.0-20171129192339-a8b929477797/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=