所以，我想弄清楚如何获取 Freebase 数据库中图像的 URL。我想要一张旧金山的照片。这就是我获得旧金山主题的方式：
https://www.googleapis.com/freebase/v1sandbox/topic/%2Fen%2Fsan_francisco?key=MY_API_KEY
响应包含图像，例如：
{
text: "San Francisco Skyline",
lang: "en",
id: "/m/04j74yh",
creator: "/user/carmenmfenn1",
timestamp: "2008-09-01T13:37:22.000Z"
}
所以我然后再次调用 GET API 来获取图像：
https://www.googleapis.com/freebase/v1sandbox/topic/%2Fm%2F04j74yh?key=MY_API_KEY
这会返回有关图像的大量信息，例如媒体类型、大小等。但我在那里看不到任何 URL。有一些 ID（blob id、mid）。我不确定如何继续获取图像的 URL。有任何想法吗？
这是完整的回应：
{
id: "/m/04j74yh",
property: {
/common/image/appears_in_topic_gallery: {
valuetype: "object",
values: [
{
text: "San Francisco",
lang: "en",
id: "/m/0d6lp",
creator: "/user/carmenmfenn1",
timestamp: "2008-09-01T13:37:22.000Z"
}
],
count: 1
},
/common/image/size: {
valuetype: "compound",
values: [
{
text: "640.0 - 330.0 - Freebase Data Team - Rectangle Size",
lang: "en",
id: "/m/02bpzld",
creator: "/user/carmenmfenn1",
timestamp: "2008-09-01T13:37:22.000Z",
property: {
/measurement_unit/rect_size/x: {
valuetype: "float",
values: [
{
text: "640.0",
lang: "en",
value: 640,
creator: "/user/mwcl_images",
timestamp: "2007-04-15T23:03:01.001Z"
}
],
count: 1
},
/measurement_unit/rect_size/y: {
valuetype: "float",
values: [
{
text: "330.0",
lang: "en",
value: 330,
creator: "/user/mwcl_images",
timestamp: "2007-04-15T23:03:01.001Z"
}
],
count: 1
},
/type/object/attribution: {
valuetype: "object",
values: [
{
text: "Freebase Data Team",
lang: "en",
id: "/m/0220tm0",
creator: "/user/mwcl_images",
timestamp: "2007-04-15T23:03:01.001Z"
}
],
count: 1
},
/type/object/type: {
valuetype: "object",
values: [
{
text: "Rectangle Size",
lang: "en",
id: "/measurement_unit/rect_size",
creator: "/user/mwcl_images",
timestamp: "2007-04-15T23:03:01.001Z"
}
],
count: 1
}
}
}
],
count: 1
},
/common/licensed_object/license: {
valuetype: "object",
values: [
{
text: "CC-BY-2.5",
lang: "en",
id: "/m/01xrw11",
creator: "/user/carmenmfenn1",
timestamp: "2008-09-01T13:37:22.000Z"
}
],
count: 1
},
/common/topic/notable_for: {
valuetype: "object",
values: [
{
text: "Content",
lang: "en",
id: "/type/content"
}
],
count: 1
},
/common/topic/notable_types: {
valuetype: "object",
values: [
{
text: "Content",
lang: "en",
id: "/type/content",
timestamp: "2013-05-17T00:04:43.942Z"
}
],
count: 1
},
/type/content/blob_id: {
valuetype: "string",
values: [
{
text: "8debf723b25edb43b413bcb2890c4f4fe6ec5e5b2c7ce9c7e1f2aee273b0d0fe",
lang: "",
value: "8debf723b25edb43b413bcb2890c4f4fe6ec5e5b2c7ce9c7e1f2aee273b0d0fe",
creator: "/user/content_administrator",
timestamp: "2008-09-01T13:37:20.000Z"
}
],
count: 1
},
/type/content/length: {
valuetype: "int",
values: [
{
text: "47162",
lang: "en",
value: 47162,
creator: "/user/content_administrator",
timestamp: "2008-09-01T13:37:20.000Z"
}
],
count: 1
},
/type/content/media_type: {
valuetype: "object",
values: [
{
text: "image/jpeg",
lang: "en",
id: "/m/08x8",
creator: "/user/content_administrator",
timestamp: "2008-09-01T13:37:20.000Z"
}
],
count: 1
},
/type/object/attribution: {
valuetype: "object",
values: [
{
text: "Freebase Staff",
lang: "en",
id: "/m/05g",
creator: "/user/content_administrator",
timestamp: "2008-09-01T13:37:20.000Z"
}
],
count: 1
},
/type/object/mid: {
valuetype: "key",
values: [
{
text: "/m/04j74yh",
lang: "",
value: "/m/04j74yh"
}
],
count: 1
},
/type/object/name: {
valuetype: "string",
values: [
{
text: "San Francisco Skyline",
lang: "en",
value: "San Francisco Skyline",
creator: "/user/carmenmfenn1",
timestamp: "2008-09-01T13:42:34.000Z"
}
],
count: 1
},
/type/object/type: {
valuetype: "object",
values: [
{
text: "Image",
lang: "en",
id: "/common/image",
creator: "/user/content_administrator",
timestamp: "2008-09-01T13:37:20.000Z"
},
{
text: "Content",
lang: "en",
id: "/type/content",
creator: "/user/content_administrator",
timestamp: "2008-09-01T13:37:20.000Z"
}
],
count: 2
},
/type/object/guid: {
valuetype: "string",
values: [
{
text: "#9202a8c04000641f80000000090393af",
lang: "",
value: "#9202a8c04000641f80000000090393af"
}
],
count: 1
},
/type/object/creator: {
valuetype: "object",
values: [
{
text: "content_administrator",
lang: "",
id: "/user/content_administrator",
timestamp: "2008-09-01T13:37:20.000Z"
}
],
count: 1
},
/type/object/timestamp: {
valuetype: "datetime",
values: [
{
text: "2008-09-01T13:37:20.000Z",
lang: "en",
value: "2008-09-01T13:37:20.000Z"
}
],
count: 1
},
/type/object/permission: {
valuetype: "object",
values: [
{
text: "/boot/all_permission",
lang: "",
id: "/boot/all_permission"
}
],
count: 1
}
}
}