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Go

Google Contacts - Retrieve as JSON

See more Google APIs Examples

Demonstrates how to retrieve Google Contacts as JSON.

Chilkat Go Downloads

Go
    success := false

    // This example requires the Chilkat API to have been previously unlocked.
    // See Global Unlock Sample for sample code.

    // --------------------------------------------------------------------------------------------------------
    // Note: The code for setting up the Chilkat REST object and making the initial connection can be done once.
    // Once connected, the REST object may be re-used for many REST API calls.
    // (It's a good idea to put the connection setup code in a separate function/subroutine.)
    // --------------------------------------------------------------------------------------------------------

    // It is assumed we previously obtained an OAuth2 access token.
    // This example loads the JSON access token file 
    // saved by this example: Get Google Contacts OAuth2 Access Token

    jsonToken := chilkat.NewJsonObject()
    success = jsonToken.LoadFile("qa_data/tokens/googleContacts.json")
    if success != true {
        fmt.Println("Failed to load googleContacts.json")
        jsonToken.DisposeJsonObject()
        return
    }

    gAuth := chilkat.NewAuthGoogle()
    gAuth.SetAccessToken(jsonToken.StringOf("access_token"))

    rest := chilkat.NewRest()

    // Connect using TLS.
    bAutoReconnect := true
    success = rest.Connect("www.google.com",443,true,bAutoReconnect)

    // Provide the authentication credentials (i.e. the access token)
    rest.SetAuthGoogle(gAuth)

    // ----------------------------------------------
    // OK, the REST connection setup is completed..
    // ----------------------------------------------

    // To retrieve the contacts, we need to send the following:

    // 	GET /m8/feeds/contacts/default/full
    // 	GData-Version: 3.0

    // To get the contacts data in JSON format, set the "alt" query parameter to "json"
    rest.AddQueryParam("alt","json")
    rest.AddHeader("GData-Version","3.0")

    sbResponseBody := chilkat.NewStringBuilder()
    success = rest.FullRequestNoBodySb("GET","/m8/feeds/contacts/default/full",sbResponseBody)
    if success != true {
        fmt.Println(rest.LastErrorText())
        jsonToken.DisposeJsonObject()
        gAuth.DisposeAuthGoogle()
        rest.DisposeRest()
        sbResponseBody.DisposeStringBuilder()
        return
    }

    // A successful response will have a status code equal to 200.
    if rest.ResponseStatusCode() != 200 {
        fmt.Println("response status code = ", rest.ResponseStatusCode())
        fmt.Println("response status text = ", rest.ResponseStatusText())
        fmt.Println("response header: ", rest.ResponseHeader())
        fmt.Println("response body: ", *sbResponseBody.GetAsString())
        jsonToken.DisposeJsonObject()
        gAuth.DisposeAuthGoogle()
        rest.DisposeRest()
        sbResponseBody.DisposeStringBuilder()
        return
    }

    // If the 200 response was received, then the contacts JSON is contained
    // in the response body.
    json := chilkat.NewJsonObject()
    json.LoadSb(sbResponseBody)
    json.SetEmitCompact(false)

    // Save the pretty-printed JSON response to a file.
    sbResponseBody.Clear()
    json.EmitSb(sbResponseBody)
    sbResponseBody.WriteFile("qa_output/google_contacts.json","utf-8",false)

    // Parse the Google Contacts JSON, and iterate over the contacts..
    totalResults := json.IntOf("feed.openSearch$totalResults.$t")
    startIndex := json.IntOf("feed.openSearch$startIndex.$t")
    itemsPerPage := json.IntOf("feed.openSearch$itemsPerPage.$t")
    fmt.Println("totalResults = ", totalResults)
    fmt.Println("startIndex = ", startIndex)
    fmt.Println("itemsPerPage = ", itemsPerPage)

    numEntries := json.SizeOfArray("feed.entry")
    i := 0
    for i < numEntries {
        json.SetI(i)
        fmt.Println(i + 1, " ----")
        fmt.Println("title: ", *json.StringOf("feed.entry[i].title.$t"))

        fullName := json.StringOf("feed.entry[i].gd$name.gd$fullName.$t")
        if json.LastMethodSuccess() == true {
            fmt.Println("fullName: ", *fullName)
        }

        // There can be multiple email addresses, so it's stored as a JSON array..
        numEmailAddresses := json.SizeOfArray("feed.entry[i].gd$email")
        j := 0
        for j < numEmailAddresses {
            emailAddress := json.StringOf("feed.entry[i].gd$email[j].address")
            if json.LastMethodSuccess() == true {
                fmt.Println("email address: ", *emailAddress)
            }

            j = j + 1
        }

        i = i + 1
    }

    // A sample Google Contacts JSON response:

    // 	{ 
    // 	  "version": "1.0",
    // 	  "encoding": "UTF-8",
    // 	  "feed": { 
    // 	    "xmlns": "http://www.w3.org/2005/Atom",
    // 	    "xmlns$openSearch": "http://a9.com/-/spec/opensearch/1.1/",
    // 	    "xmlns$gContact": "http://schemas.google.com/contact/2008",
    // 	    "xmlns$batch": "http://schemas.google.com/gdata/batch",
    // 	    "xmlns$gd": "http://schemas.google.com/g/2005",
    // 	    "gd$etag": "\"QHw5eTVSLyt7I2A9XRFaE0kNTwI.\"",
    // 	    "id": { 
    // 	      "$t": "chilkat.support@gmail.com"
    // 	    },
    // 	    "updated": { 
    // 	      "$t": "2016-11-17T01:57:41.221Z"
    // 	    },
    // 	    "category": [
    // 	      { 
    // 	        "scheme": "http://schemas.google.com/g/2005#kind",
    // 	        "term": "http://schemas.google.com/contact/2008#contact"
    // 	      }
    // 	    ],
    // 	    "title": { 
    // 	      "$t": "Chilkat Support's Contacts"
    // 	    },
    // 	    "link": [
    // 	      { 
    // 	        "rel": "alternate",
    // 	        "type": "text/html",
    // 	        "href": "https://www.googleapis.com/"
    // 	      },
    // 	      { 
    // 	        "rel": "http://schemas.google.com/g/2005#feed",
    // 	        "type": "application/atom+xml",
    // 	        "href": "https://www.googleapis.com/m8/feeds/contacts/chilkat.support%40gmail.com/full"
    // 	      },
    // 	      { 
    // 	        "rel": "http://schemas.google.com/g/2005#post",
    // 	        "type": "application/atom+xml",
    // 	        "href": "https://www.googleapis.com/m8/feeds/contacts/chilkat.support%40gmail.com/full"
    // 	      },
    // 	      { 
    // 	        "rel": "http://schemas.google.com/g/2005#batch",
    // 	        "type": "application/atom+xml",
    // 	        "href": "https://www.googleapis.com/m8/feeds/contacts/chilkat.support%40gmail.com/full/batch"
    // 	      },
    // 	      { 
    // 	        "rel": "self",
    // 	        "type": "application/atom+xml",
    // 	        "href": "https://www.googleapis.com/m8/feeds/contacts/chilkat.support%40gmail.com/full?max-results=25&alt=json"
    // 	      },
    // 	      { 
    // 	        "rel": "next",
    // 	        "type": "application/atom+xml",
    // 	        "href": "https://www.googleapis.com/m8/feeds/contacts/chilkat.support%40gmail.com/full?max-results=25&alt=json&start-index=26"
    // 	      }
    // 	    ],
    // 	    "author": [
    // 	      { 
    // 	        "name": { 
    // 	          "$t": "Chilkat Support"
    // 	        },
    // 	        "email": { 
    // 	          "$t": "chilkat.support@gmail.com"
    // 	        }
    // 	      }
    // 	    ],
    // 	    "generator": { 
    // 	      "version": "1.0",
    // 	      "uri": "http://www.google.com/m8/feeds",
    // 	      "$t": "Contacts"
    // 	    },
    // 	    "openSearch$totalResults": { 
    // 	      "$t": "350"
    // 	    },
    // 	    "openSearch$startIndex": { 
    // 	      "$t": "1"
    // 	    },
    // 	    "openSearch$itemsPerPage": { 
    // 	      "$t": "25"
    // 	    },
    // 	    "entry": [
    // 	      { 
    // 	        "id": { 
    // 	          "$t": "http://www.google.com/m8/feeds/contacts/chilkat.support%40gmail.com/base/0"
    // 	        },
    // 	        "gd$etag": "\"SX8zcTVSLyt7I2A9WxBXFU4MQwI.\"",
    // 	        "updated": { 
    // 	          "$t": "2010-01-26T20:07:48.189Z"
    // 	        },
    // 	        "app$edited": { 
    // 	          "xmlns$app": "http://www.w3.org/2007/app",
    // 	          "$t": "2010-01-26T20:07:48.189Z"
    // 	        },
    // 	        "category": [
    // 	          { 
    // 	            "scheme": "http://schemas.google.com/g/2005#kind",
    // 	            "term": "http://schemas.google.com/contact/2008#contact"
    // 	          }
    // 	        ],
    // 	        "title": { 
    // 	          "$t": "Joe Sample"
    // 	        },
    // 	        "link": [
    // 	          { 
    // 	            "rel": "http://schemas.google.com/contacts/2008/rel#photo",
    // 	            "type": "image/*",
    // 	            "href": "https://www.googleapis.com/m8/feeds/photos/media/chilkat.support%40gmail.com/0"
    // 	          },
    // 	          { 
    // 	            "rel": "self",
    // 	            "type": "application/atom+xml",
    // 	            "href": "https://www.googleapis.com/m8/feeds/contacts/chilkat.support%40gmail.com/full/0"
    // 	          },
    // 	          { 
    // 	            "rel": "edit",
    // 	            "type": "application/atom+xml",
    // 	            "href": "https://www.googleapis.com/m8/feeds/contacts/chilkat.support%40gmail.com/full/0"
    // 	          }
    // 	        ],
    // 	        "gd$name": { 
    // 	          "gd$fullName": { 
    // 	            "$t": "Joe Sample"
    // 	          },
    // 	          "gd$givenName": { 
    // 	            "$t": "Joe"
    // 	          },
    // 	          "gd$familyName": { 
    // 	            "$t": "Sample"
    // 	          }
    // 	        },
    // 	        "gd$email": [
    // 	          { 
    // 	            "address": "somebody@gmail.com",
    // 	            "primary": "true",
    // 	            "rel": "http://schemas.google.com/g/2005#other"
    // 	          }
    // 	        ]
    // 	      },
    // 		... more entries ...
    // 	

    jsonToken.DisposeJsonObject()
    gAuth.DisposeAuthGoogle()
    rest.DisposeRest()
    sbResponseBody.DisposeStringBuilder()
    json.DisposeJsonObject()