Update docs for HTTP API

In /query and /mutate endpoint, we need to specify Content-Type -.
 * /query -> application/graphql or application/json
 * /mutate -> application/rdf or application/json

Author: mangalaman93

dgraph/cmd/alpha/notes.txt

@@ -1,4 +1,4 @@
-curl localhost:8080/query -XPOST -d '{
+curl -H "Content-Type: application/graphql" localhost:8080/query -XPOST -d '{
 me(_xid_: m.06pj8) {
         type.object.name.en
         film.director.film {

dgraph/cmd/bulk/systest/run.sh

@@ -37,7 +37,7 @@ for suite in $script_dir/suite*; do
 	sleep 2
 
 	popd >/dev/null # out of tmp
-	result=$(curl --silent localhost:8080/query -XPOST -d @$suite/query.json)
+	result=$(curl --silent -H "Content-Type: application/graphql" localhost:8080/query -XPOST -d @$suite/query.json)
 	if ! $(jq --argfile a <(echo $result) --argfile b $suite/result.json -n 'def post_recurse(f): def r: (f | select(. != null) | r), .; r; def post_recurse: post_recurse(.[]?); ($a | (post_recurse | arrays) |= sort) as $a | ($b | (post_recurse | arrays) |= sort) as $b | $a == $b')
 	then
 		echo "Actual result doesn't match expected result:"

dgraph/cmd/bulk/systest/test-bulk-schema.sh

@@ -99,7 +99,7 @@ predicate_with_default_type:default  .
 predicate_with_index_no_uid_count:string @index(exact) .
 ' &>/dev/null
 
-  curl localhost:$HTTP_PORT/mutate?commitNow=true -X POST -d $'
+  curl -H "Content-Type: application/rdf" localhost:$HTTP_PORT/mutate?commitNow=true -X POST -d $'
 {
   set {
     _:company1 <predicate_with_default_type> "CompanyABC" .
@@ -112,7 +112,7 @@ function QuerySchema
 {
   INFO "running schema query"
   local out_file="schema.out"
-  curl -sS localhost:$HTTP_PORT/query -XPOST -d'schema(pred:[genre,language,name,revenue,predicate_with_default_type,predicate_with_index_no_uid_count,predicate_with_no_uid_count]) {}' | python -c "import json,sys; d=json.load(sys.stdin); json.dump(d['data'],sys.stdout,sort_keys=True,indent=2)"  > $out_file
+  curl -sS -H "Content-Type: application/graphql" localhost:$HTTP_PORT/query -XPOST -d'schema(pred:[genre,language,name,revenue,predicate_with_default_type,predicate_with_index_no_uid_count,predicate_with_no_uid_count]) {}' | python -c "import json,sys; d=json.load(sys.stdin); json.dump(d['data'],sys.stdout,sort_keys=True,indent=2)"  > $out_file
   echo >> $out_file
 }
 

query/benchmark/README.md

@@ -12,7 +12,7 @@ rm -Rf dumpsg
 NUMS="10 56 300"
 
 for NUM in $NUMS; do
-	curl localhost:8912/query -XPOST -d "{
+	curl -H "Content-Type: application/graphql" localhost:8912/query -XPOST -d "{
 	        me(_xid_:m.08624h) {
 	         type.object.name.en
 	         film.actor.film(first: $NUM) {
@@ -42,7 +42,7 @@ rm -Rf dumpsg
 NUMS="10 31 100"
 
 for NUM in $NUMS; do
-	curl localhost:8912/query -XPOST -d "{
+	curl -H "Content-Type: application/graphql" localhost:8912/query -XPOST -d "{
         me(_xid_:m.05dxl_) {
           type.object.name.en
           film.director.film(first: $NUM)  {

query/benchmark/run.sh

@@ -19,7 +19,7 @@ dgraph -dumpsg dumpsg -port 8912 &
 sleep 2
 
 for ACTOR in $ACTORS; do
-  curl localhost:8912/query -XPOST -d "
+  curl -H "Content-Type: application/graphql" localhost:8912/query -XPOST -d "
   {
     me(_xid_:${ACTOR}) {
       type.object.name.en
@@ -42,7 +42,7 @@ done
 rm -f dumpsg/*
 
 for DIRECTOR in $DIRECTORS; do
-  curl localhost:8912/query -XPOST -d "
+  curl -H "Content-Type: application/graphql" localhost:8912/query -XPOST -d "
   {
     me(_xid_:${DIRECTOR}) {
       type.object.name.en

wiki/content/clients/index.md

@@ -470,10 +470,10 @@ Similar to the Go client example, we use a bank account transfer example.
 
 A client built on top of the HTTP API will need to track three pieces of state
 for each transaction.
-  
+
 1. A start timestamp (`start_ts`). This uniquely identifies a transaction,
    and doesn't change over the transaction lifecycle.
-  
+
 2. The set of keys modified by the transaction (`keys`). This aids in
    transaction conflict detection.
 
@@ -535,12 +535,14 @@ new transaction is initiated.**
 
 ### Run a query
 
-To query the database, the `/query` endpoint is used.
+To query the database, the `/query` endpoint is used. Remember to set the content
+type header to `application/graphql` in order to ensure that the body of the request
+is correctly parsed.
 
 To get the balances for both accounts:
 
 ```sh
-$ curl -X POST localhost:8080/query -d $'
+$ curl -H "Content-Type: application/graphql" -X POST localhost:8080/query -d $'
 {
   balances(func: anyofterms(name, "Alice Bob")) {
     uid
@@ -605,10 +607,12 @@ Note that we have to refer to the Alice and Bob nodes by UID in the RDF format.
 
 We now send the mutations via the `/mutate` endpoint. We need to provide our
 transaction start timestamp as a path parameter, so that Dgraph knows which
-transaction the mutation should be part of.
+transaction the mutation should be part of. We also need to set content type
+header to `application/rdf` in order to specify that mutation is written in
+rdf format.
 
 ```sh
-$ curl -X POST localhost:8080/mutate?startTs=4 -d $'
+$ curl -H "Content-Type: application/rdf" -X POST localhost:8080/mutate?startTs=4 -d $'
 {
   set {
     <0x1> <balance> "110" .
@@ -732,6 +736,7 @@ Example of a compressed request via curl:
 ```sh
 $ curl -X POST \
   -H 'Content-Encoding: gzip' \
+	-H "Content-Type: application/rdf" \
   localhost:8080/mutate?commitNow=true --data-binary @mutation.gz
 ```
 
@@ -740,6 +745,7 @@ Example of a compressed request via curl:
 ```sh
 $ curl -X POST \
   -H 'Accept-Encoding: gzip' \
+	-H "Content-Type: application/graphql"
   localhost:8080/query -d $'schema {}' | gzip --decompress
 ```
 
@@ -759,13 +765,14 @@ $ zcat query.gz # query.gz is gzipped compressed
 $ curl -X POST \
   -H 'Content-Encoding: gzip' \
   -H 'Accept-Encoding: gzip' \
+	-H "Content-Type: application/graphql"
   localhost:8080/query --data-binary @query.gz | gzip --decompress
 ```
 
 {{% notice "note" %}}
 Curl has a `--compressed` option that automatically requests for a compressed response (`Accept-Encoding` header) and decompresses the compressed response.
 
 ```sh
-$ curl -X POST --compressed localhost:8080/query -d $'schema {}'
+$ curl -X POST --compressed -H "Content-Type: application/graphql" localhost:8080/query -d $'schema {}'
 ```
 {{% /notice %}}

wiki/content/get-started/index.md

@@ -201,7 +201,7 @@ Ratel's default port is 8081, so override it using -p 8000.
 ## Step 3: Run Queries
 {{% notice "tip" %}}Once Dgraph is running, you can access Ratel at [`http://localhost:8000`](http://localhost:8000). It allows browser-based queries, mutations and visualizations.
 
-The mutations and queries below can either be run from the command line using `curl localhost:8080/query -XPOST -d $'...'` or by pasting everything between the two `'` into the running user interface on localhost.{{% /notice %}}
+The mutations and queries below can either be run from the command line using `curl -H "Content-Type: application/graphql" localhost:8080/query -XPOST -d $'...'` or by pasting everything between the two `'` into the running user interface on localhost.{{% /notice %}}
 
 ### Dataset
 The dataset is a movie graph, where and the graph nodes are entities of the type directors, actors, genres, or movies.
@@ -211,7 +211,7 @@ Changing the data stored in Dgraph is a mutation.  The following mutation stores
 
 
 ```sh
-curl localhost:8080/mutate?commitNow=true -XPOST -d $'
+curl -H "Content-Type: application/rdf" localhost:8080/mutate?commitNow=true -XPOST -d $'
 {
   set {
    _:luke <name> "Luke Skywalker" .
@@ -277,7 +277,7 @@ curl localhost:8080/alter -XPOST -d $'
 Run this query to get all the movies. The query works below all the movies have a starring edge
 
 ```sh
-curl localhost:8080/query -XPOST -d $'
+curl -H "Content-Type: application/graphql" localhost:8080/query -XPOST -d $'
 {
  me(func: has(starring)) {
    name
@@ -291,7 +291,7 @@ Run this query to get "Star Wars" movies released after "1980".  Try it in the u
 
 
 ```sh
-curl localhost:8080/query -XPOST -d $'
+curl -H "Content-Type: application/graphql" localhost:8080/query -XPOST -d $'
 {
   me(func:allofterms(name, "Star Wars")) @filter(ge(release_date, "1980")) {
     name

wiki/content/howto/index.md

@@ -118,7 +118,7 @@ $ curl localhost:8080/alter -d '
 ```
 
 ```sh
-$ curl localhost:8080/mutate?commitNow=true -d '{
+$ curl -H "Content-Type: application/rdf" localhost:8080/mutate?commitNow=true -d '{
   set {
     _:dgraph <name> "Dgraph" .
     _:dgraph <url> "https://github.com/dgraph-io/dgraph" .
@@ -128,7 +128,7 @@ $ curl localhost:8080/mutate?commitNow=true -d '{
 ```
 
 ```sh
-$ curl localhost:8080/mutate?commitNow=true -d '{
+$ curl -H "Content-Type: application/rdf" localhost:8080/mutate?commitNow=true -d '{
   set {
     _:badger <name> "Badger" .
     _:badger <url> "https://github.com/dgraph-io/badger" .

wiki/content/mutations/index.md

@@ -288,7 +288,7 @@ Mutations can be done over HTTP by making a `POST` request to an Alpha's `/mutat
 To run a `set` mutation:
 
 ```sh
-curl -X POST localhost:8080/mutate?commitNow=true -d $'
+curl -H "Content-Type: application/rdf" -X POST localhost:8080/mutate?commitNow=true -d $'
 {
   set {
     _:alice <name> "Alice" .
@@ -299,7 +299,7 @@ curl -X POST localhost:8080/mutate?commitNow=true -d $'
 To run a `delete` mutation:
 
 ```sh
-curl -X POST localhost:8080/mutate?commitNow=true -d $'
+curl -H "Content-Type: application/rdf" -X POST localhost:8080/mutate?commitNow=true -d $'
 {
   delete {
     # Example: Alice's UID is 0x56f33
@@ -310,8 +310,8 @@ curl -X POST localhost:8080/mutate?commitNow=true -d $'
 
 To run an RDF mutation stored in a file, use curl's `--data-binary` option so that, unlike the `-d` option, the data is not URL encoded.
 
-```
-curl -X POST localhost:8080/mutate?commitNow=true --data-binary @mutation.txt
+```sh
+curl -H "Content-Type: application/rdf" -X POST localhost:8080/mutate?commitNow=true --data-binary @mutation.txt
 ```
 
 ## JSON Mutation Format
@@ -646,15 +646,21 @@ Deletion operations are the same as [Deleting literal values]({{< relref "#delet
 
 ### Using JSON operations via cURL
 
+First you have to configure the HTTP header to specify content-type.
+
+```sh
+-H 'Content-Type: application/json'
+```
+
 {{% notice "note" %}}
 In order to use `jq` for JSON formatting you need the `jq` package. See the
 [`jq` downloads](https://stedolan.github.io/jq/download/) page for installation
 details. You can also use Python's built in `json.tool` module with `python -m
 json.tool` to do JSON formatting.
 {{% /notice %}}
 
-```BASH
-curl -X POST localhost:8080/mutate?mutationType=json&commitNow=true -d  $'
+```sh
+curl -H "Content-Type: application/json" -X POST localhost:8080/mutate?commitNow=true -d  $'
     {
       "set": [
         {
@@ -670,8 +676,8 @@ curl -X POST localhost:8080/mutate?mutationType=json&commitNow=true -d  $'
 
 To delete:
 
-```BASH
-curl -X POST localhost:8080/mutate?mutationType=json&commitNow=true -d  $'
+```sh
+curl -H "Content-Type: application/json" -X POST localhost:8080/mutate?commitNow=true -d  $'
     {
       "delete": [
         {
@@ -683,6 +689,6 @@ curl -X POST localhost:8080/mutate?mutationType=json&commitNow=true -d  $'
 
 Mutation with a JSON file:
 
-```
-curl -X POST localhost:8080/mutate?mutationType=json&commitNow=true -d @data.json
+```sh
+curl -H "Content-Type: application/json" -X POST localhost:8080/mutate?commitNow=true -d @data.json
 ```

wiki/content/query-language/index.md

@@ -1930,8 +1930,8 @@ For the purposes of debugging, you can attach a query parameter `debug=true` to
 - `start_ts`: The logical start timestamp of the transaction.
 
 Query with debug as a query parameter
-```
-curl "http://localhost:8080/query?debug=true" -XPOST -d $'{
+```sh
+curl -H "Content-Type: application/graphql" http://localhost:8080/query?debug=true -XPOST -d $'{
   tbl(func: allofterms(name@en, "The Big Lebowski")) {
     name@en
   }
@@ -2512,7 +2512,7 @@ curl localhost:8080/alter -XPOST -d $'
 ```
 
 ```sh
-curl localhost:8080/mutate?commitNow=true -XPOST -d $'
+curl -H "Content-Type: application/rdf" localhost:8080/mutate?commitNow=true -XPOST -d $'
 {
   set {
 
@@ -2885,7 +2885,7 @@ curl localhost:8080/alter -XPOST -d $'
 ```
 
 ```sh
-curl localhost:8080/mutate?commitNow=true -XPOST -d $'
+curl -H "Content-Type: application/rdf" localhost:8080/mutate?commitNow=true -XPOST -d $'
 {
   set {
     _:a <friend> _:b (weight=0.1) .
@@ -2901,8 +2901,8 @@ curl localhost:8080/mutate?commitNow=true -XPOST -d $'
 ```
 
 The shortest path between Alice and Mallory (assuming UIDs 0x2 and 0x5 respectively) can be found with query:
-```
-curl localhost:8080/query -XPOST -d $'{
+```sh
+curl -H "Content-Type: application/graphql" localhost:8080/query -XPOST -d $'{
  path as shortest(from: 0x2, to: 0x5) {
   friend
  }
@@ -2939,8 +2939,8 @@ Which returns the following results. (Note, without considering the `weight` fac
 ```
 
 The shortest two paths are returned with:
-```
-curl localhost:8080/query -XPOST -d $'{
+```sh
+curl -H "Content-Type: application/graphql" localhost:8080/query -XPOST -d $'{
  path as shortest(from: 0x2, to: 0x5, numpaths: 2) {
   friend
  }
@@ -2953,8 +2953,8 @@ curl localhost:8080/query -XPOST -d $'{
 Edges weights are included by using facets on the edges as follows.
 
 {{% notice "note" %}}One facet per predicate in the shortest query block is allowed.{{% /notice %}}
-```
-curl localhost:8080/query -XPOST -d $'{
+```sh
+curl -H "Content-Type: application/graphql" localhost:8080/query -XPOST -d $'{
  path as shortest(from: 0x2, to: 0x5) {
   friend @facets(weight)
  }
@@ -3012,8 +3012,8 @@ curl localhost:8080/query -XPOST -d $'{
 ```
 
 Constraints can be applied to the intermediate nodes as follows.
-```
-curl localhost:8080/query -XPOST -d $'{
+```sh
+curl -H "Content-Type: application/graphql" localhost:8080/query -XPOST -d $'{
   path as shortest(from: 0x2, to: 0x5) {
     friend @filter(not eq(name, "Bob")) @facets(weight)
     relative @facets(liking)
@@ -3027,8 +3027,8 @@ curl localhost:8080/query -XPOST -d $'{
 
 The k-shortest path algorithm (used when numPaths > 1)also accepts the arguments ```minweight``` and ```maxweight```, which take a float as their value. When they are passed, only paths within the weight range ```[minweight, maxweight]``` will be considered as valid paths. This can be used, for example, to query the shortest paths that traverse between 2 and 4 nodes.
 
-```
-curl localhost:8080/query -XPOST -d $'{
+```sh
+curl -H "Content-Type: application/graphql" localhost:8080/query -XPOST -d $'{
  path as shortest(from: 0x2, to: 0x5, numpaths: 2, minweight: 2, maxweight: 4) {
   friend
  }
@@ -3067,8 +3067,8 @@ Some points to keep in mind while using recurse queries are:
 
 `fragment` keyword allows you to define new fragments that can be referenced in a query, as per [GraphQL specification](https://facebook.github.io/graphql/#sec-Language.Fragments). The point is that if there are multiple parts which query the same set of fields, you can define a fragment and refer to it multiple times instead. Fragments can be nested inside fragments, but no cycles are allowed. Here is one contrived example.
 
-```
-curl localhost:8080/query -XPOST -d $'
+```sh
+curl -H "Content-Type: application/graphql" localhost:8080/query -XPOST -d $'
 query {
   debug(func: uid(1)) {
     name@en