react-native-azure-cosmos-gremlin
This package provide rest api for azure cosmos germlin graph data base query access
Install
Step 1
npm i react-native-azure-cosmos-gremlin --saveStep 2 Azure App Function
create APP FUNCTION project on VS and paste AzureGermlin.cs file content in this repository on it
how to create azure app function :
copy this function on your azure app function body
[FunctionName("AzureGermlin")]
public static async Task<AzureResult> AzureGermlin(
[HttpTrigger(AuthorizationLevel.Function, "get", "post", Route = null)] HttpRequest req,
ILogger log)
{
try
{
var tdate = req.Headers["x-ms-date"].FirstOrDefault();
var reqDate = Convert.ToDateTime(tdate);
if (reqDate < DateTime.UtcNow.AddMinutes(-10))
{
throw new HttpResponseException(HttpStatusCode.BadRequest);
}
var auth = req.Headers["Authorization"].FirstOrDefault();
string requestBody = await new StreamReader(req.Body).ReadToEndAsync();
var data = JsonConvert.DeserializeObject<GraphQuery>(requestBody);
var he = $"POST{data.Parameters.Count}AzureGermlin{tdate}";
string password = $"{YOUR_AZURE_GERMLIN_DB_PASSWORD}";
var hmacSha256 = new System.Security.Cryptography.HMACSHA256
{
Key = Convert.FromBase64String(password)
};
byte[] hashPayLoad = hmacSha256.ComputeHash(System.Text.Encoding.UTF8.GetBytes(he));
string signature = Convert.ToBase64String(hashPayLoad);
if (signature != auth)
{
throw new HttpResponseException(HttpStatusCode.Unauthorized);
}
data.Parameters.ForEach(t =>
{
data.Query = data.Query.Replace(t.Name, t.Value);
});
var gremlinServer = new GremlinServer(YOU_AZURE_GERMLIN_DB_HOST, 443, enableSsl: true,
username: YOU_AZURE_GERMLIN_DB_USERNAME,
password: YOUR_AZURE_GERMLIN_DB_PASSWORD);
using (var gremlinClient = new GremlinClient(gremlinServer,
new GraphSON2Reader(), new GraphSON2Writer(), GremlinClient.GraphSON2MimeType))
{
var resultSet = await gremlinClient.SubmitAsync<dynamic>(data.Query);
return new AzureResult() { status = 200, result = resultSet };
}
}
catch (Exception ex)
{
return new AzureResult() { status = 500, result = ex.Message };
}
}
You can follow this articale to implement your own c# germlin app function
Usage
Import library
import { azuregermlinfetch, initCosmosGermlin } from 'react-native-azure-cosmos-gremlin/germlin'init azure cosmos germlin setting
constructor(props) {
super(props);
initAzureCosmos({
masterkey: "YOUR_GERMLIN_KEY",
methodname: "YOUR_APP_FUNCTION_METHOD_NAME",
serviceurl: "YOUR_APP_FUNCTION_SERVICE_URL"
})
....
}upload file from cameraroll :
fetchgermlin = async () => {
const response = await azuregermlinfetch({
query: "g.addV('user').property('id', '@id').property('code', '@code').property('photoUri', '@photoUri').property('uid', '@uid')",
"parameters": [
{ name: "@id", value: "10000000" },
{ name: "@code", value: "001" },
{ name: "@photoUri", value: "" },
{ name: "@uid", value: "blazer.road@gmail.com" },
]
})
const resData = await response.json();
console.log(resData);
}
