This sample demonstrates how to make advanced callouts from API proxies to backend services secured using OAuth.

Specifically, the API Proxy uses JavaScript to obtain an access token using the 'client credentials' grant type. To obtain an access token, the API proxy presents an API key and secret to the Azure translator service. In exchange, the Azure service returns an access token that can be used for multiple requests.

The API proxy uses API Services Cache resource to store access tokens in memory. (Otherwise, the API proxy would be required to obtain an access token for each call, resulting in significant overhead and probable performance degradation.)

You can use this sample as template for API proxies that must present tokens (whether API keys or access tokens) to access backend services.

This sample uses the Twitter Search API to find tweets in a given language and translate them to the language the query was made in using the Microsoft Translator API.

A demo application that performs a search and renders the results in HTML is included.

curl -v "http://demo-prod.apigee.net/outbound-oauth/search.json?lang=es&q=bicycle"

Response excerpt:

{
"completed_in": 0.012,
"max_id": 268099561782931460,
"max_id_str": "268099561782931457",
"next_page": "?page=2&max_id=268099561782931457&q=bicicleta&lang=es",
"page": 1,
"query": "bicicleta",
"refresh_url": "?since_id=268099561782931457&q=bicicleta&lang=es",
"results": [{
    "created_at": "Mon, 12 Nov 2012 21:14:51 +0000",
    "from_user": "Maureira10",
    "from_user_id": 198397428,
    "from_user_id_str": "198397428",
    "from_user_name": "Álvaro Maureira ",
    "geo": null,
    "id": 268099561782931460,
    "id_str": "268099561782931457",
    "iso_language_code": "es",
    "metadata": {
        "result_type": "recent"
    },
    "profile_image_url": "http://a0.twimg.com/profile_images/2632871896/80a1fbf2075c9f0e8630aeb5b8bfcb66_normal.jpeg",
    "profile_image_url_https": "https://si0.twimg.com/profile_images/2632871896/80a1fbf2075c9f0e8630aeb5b8bfcb66_normal.jpeg",
    "source": "<a href="http://twitter.com/download/iphone">Twitter for iPhone</a>",
    "text": "I thought it was not good idea to exit at noon at bicycle to 14. I feel like the balls!",
    "to_user": null,
    "to_user_id": 0,
    "to_user_id_str": "0",
    "to_user_name": null,
    "text_orig": "Creo que NO fue buena idea salir al medio día en bicicleta al 14. Me siento como las pelotas!"
}, 
...

1. Sign up for Microsoft Translator API access, and replace the clientId and clientSecret in apiproxy/resources/jsc/api-config.js with your application credentials.

2. Create a cache in the organization and environment you will be deploying the bundle in, using the definition in oauth-token-cache.xml. This is used to cache the Translator API access token across requests. Try the following command:

   curl -v -X POST -H "Content-Type: application/xml" -d @oauth-token-cache.xml https://api.enterprise.apigee.com/v1/organizations/$ORG/environments/$ENV/caches -u myname:mypass

• The username and password that you use to login to enterprise.apigee.com.
• The name of the organization in which you have an account. Log in to enterprise.apigee.com and check account settings.

Update /setup/setenv.sh with your environment details

Run /setup/deploy.sh

For assistance, please use Apigee Support.

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Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.