Added virtualenv for easier dependencies management

Fixes #1

Author: Matthieu Vachon

.gitignore

@@ -0,0 +1,3 @@
+__pycache__
+/env
+/.envrc

README.md

@@ -1,4 +1,5 @@
-# example-graphql-python
+## dfuse GraphQL Python Example
+
 This simple program demonstrates how easy it is to query our GraphQL API over gRPC in Python. It:
 
 * Request a token from our authentication API
@@ -7,12 +8,34 @@ This simple program demonstrates how easy it is to query our GraphQL API over gR
 * Executes a simple GraphQL query
 * Prints the response
 
-#### Running the example
+### Requirements
+
+You will need to have Python3 (>= 3.4+) as well as `virtualenv` and `pip`
+`>= 15.0+`.
+
+We use a virtual environment for this example, all dependencies are listed
+in the `requirements.txt` at the root of this project.
+
+#### Quickstart
+
+First of all, visit [https://app.dfuse.io](https://app.dfuse.io) to get
+a free API key for your project.
 
-First of all, visit [https://app.dfuse.io](https://app.dfuse.io) to get `YOUR_API_KEY`.
+First, clone this repository to your work folder:
 
-~~~bash
+```bash
 git clone https://github.com/dfuse-io/example-graphql-python.git
 cd example-graphql-python
+```
+
+Setup the virtual environment and pull all dependencies:
+
+```bash
+./install_deps.sh
+```
+
+Once your environment is setup properly, simply run the `example.py` script:
+
+```bash
 python3 example.py YOUR_API_KEY_HERE
-~~~
+```

example.py

@@ -35,13 +35,13 @@ def stub():
 
 query = '''
 subscription {
-  searchTransactionsForward(query: "status:executed", limit: 10) {
+  searchTransactionsForward(query: "account:eosio.token receiver:eosio.token action:transfer", limit: 10) {
     trace {
       id
       matchingActions{
         account
         receiver
-        name 
+        name
         json
       }
     }
@@ -53,5 +53,9 @@ def stub():
 stream = dfuse_graphql.Execute(Request(query=query))
 
 for rawResult in stream:
-    result = json.loads(rawResult.data)
-    print(result['searchTransactionsForward']['trace']['matchingActions'])
+    if rawResult.errors:
+      print("An error occurred")
+      print(rawResult.errors)
+    else:
+      result = json.loads(rawResult.data)
+      print(result['searchTransactionsForward']['trace']['matchingActions'])

graphql/__pycache__/graphql_pb2.cpython-37.pyc

@@ -0,0 +1,31 @@
+#!/usr/bin/env bash
+
+ROOT="$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )"
+
+main() {
+  current_dir="`pwd`"
+  trap "cd \"$current_dir\"" EXIT
+  pushd "$ROOT" &> /dev/null
+
+  if [[ $1 == "--help" ]]; then
+    usage
+    exit 0
+  fi
+
+  # Not Windows friendly, need to be adapted here to be Windows aware
+  python3 -m venv env
+  source env/bin/activate
+  pip3 install -r requirements.txt
+}
+
+usage() {
+  echo "usage: install_deps"
+  echo ""
+  echo "Setup Python virtualenv environment and install all necessary"
+  echo "dependencies for this project. Requires venv to be available"
+  echo "in PATH and scripts expects a pip version '>= 15.0'."
+  echo ""
+  echo "Python3 is required also. No support for Python2 is provided"
+}
+
+main $@

graphql/__pycache__/graphql_pb2_grpc.cpython-37.pyc

@@ -0,0 +1,5 @@
+## The following requirements were added by pip freeze:
+grpcio==1.22.0
+grpcio-tools==1.22.0
+protobuf==3.9.1
+six==1.12.0

install_deps.sh

@@ -0,0 +1,25 @@
+#!/usr/bin/env bash
+
+ROOT="$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )"
+
+main() {
+  current_dir="`pwd`"
+  trap "cd \"$current_dir\"" EXIT
+  pushd "$ROOT" &> /dev/null
+
+  if [[ $1 == "--help" ]]; then
+    usage
+    exit 0
+  fi
+
+  pip3 freeze -r requirements.txt > requirements.txt
+}
+
+usage() {
+  echo "usage: update_deps"
+  echo ""
+  echo "Freeze the actual dependencies and update the requirements.txt file"
+  echo "used to store them."
+}
+
+main $@